790 research outputs found
Does Time Really Slow Down during a Frightening Event?
Observers commonly report that time seems to have moved in slow motion during a life-threatening event. It is unknown whether this is a function of increased time resolution during the event, or instead an illusion of remembering an emotionally salient event. Using a hand-held device to measure speed of visual perception, participants experienced free fall for 31 m before landing safely in a net. We found no evidence of increased temporal resolution, in apparent conflict with the fact that participants retrospectively estimated their own fall to last 36% longer than others' falls. The duration dilation during a frightening event, and the lack of concomitant increase in temporal resolution, indicate that subjective time is not a single entity that speeds or slows, but instead is composed of separable subcomponents. Our findings suggest that time-slowing is a function of recollection, not perception: 1a richer encoding of memory may cause a salient event to appear, retrospectively, as though it lasted longer
Synthesizing Skyrmion Molecules in Fe-Gd Thin Films
We show that properly engineered amorphous Fe-Gd alloy thin films with
perpendicular magnetic anisotropy exhibit room-temperature skyrmion molecules,
or a pair of like-polarity, opposite-helicity skyrmions. Magnetic mirror
symmetry planes present in the stripe phase, instead of chiral exchange,
determine the internal skyrmion structure and the net achirality of the
skyrmion phase. Our study shows that stripe domain engineering in amorphous
alloy thin films may enable the creation of skyrmion phases with
technologically desirable properties.Comment: 15 pages, 6 figures. Accepted for publication in Applied Physics
Letter
DâAgents: Security in a Multiple-Language, Mobile-Agent System
Abstract. Mobile-agent systems must address three security issues: protecting an individual machine, protecting a group of machines, and protecting an agent. In this chapter, we discuss these three issues in the context of DâAgents, a mobile-agent system whose agents can be written in Tcl, Java and Scheme. (DâAgents was formerly known as Agent Tcl.) First we discuss mechanisms existing in DâAgents for protecting an individual machine: (1) cryptographic authentication of the agentâs owner, (2) resource managers that make policy decisions based on the ownerâs identity, and (3) secure execution environments for each language that enforce the decisions of the resource managers. Then we discuss our planned market-based approach for protecting machine groups. Finally we consider several (partial) solutions for protecting an agent from a malicious machine.
Myths and Facts About Static Application Security Testing Tools: An Action Research at Telenor Digital
It is claimed that integrating agile and security in practice is challenging. There is the notion that security is a heavy process, requires expertise, and consumes developersâ time. These contrast with the agile vision. Regardless of these challenges, it is important for organizations to address security within their agile processes since critical assets must be protected against attacks. One way is to integrate tools that could help to identify security weaknesses during implementation and suggest methods to refactor them. We used quantitative and qualitative approaches to investigate the efficiency of the tools and what they mean to the actual users (i.e. developers) at Telenor Digital. Our findings, although not surprising, show that several barriers exist both in terms of toolâs performance and developersâ perceptions. We suggest practical ways for improvement.publishedVersio
Deep hypothermia prevents striatal alterations produced by perinatal asphyxia: Implications for the prevention of dyskinesia and psychosis
GABAergic medium spiny neurons are the main neuronal population in the striatum. Calbindin is preferentially expressed in medium spiny neurons involved in the indirect pathway. The aim of the present work is to analyze the effect of perinatal asphyxia on different subpopulations of GABAergic neurons in the striatum and to assess the outcome of deep therapeutic hypothermia. The uterus of pregnant rats was removed by cesarean section and the fetuses were exposed to hypoxia by immersion in water (19âmin) at 37°C (perinatal asphyxia). The hypothermic group was exposed to 10°C during 30âmin after perinatal asphyxia. The rats were euthanized at the age of one month (adolescent/adult rats), their brains were dissected out and coronal sections were immunolabeled for calbindin, calretinin, NeuN, and reelin. Reelin+ cells showed no staining in the striatum besides subventricular zone. The perinatal asphyxia (PA) group showed a significant decrease in calbindin neurons and a paradoxical increase in neurons estimated by NeuN staining. Moreover, calretinin+ cells, a specific subpopulation of GABAergic neurons, showed an increase caused by PA. Deep hypothermia reversed most of these alterations probably by protecting calbindin neurons. Similarly, there was a reduction of the diameter of the anterior commissure produced by the asphyxia that was prevented by hypothermic treatment.Fil: Vazquez, Pablo. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Oficina de CoordinaciĂłn Administrativa Houssay. Instituto de BiologĂa Celular y Neurociencia "Prof. Eduardo de Robertis". Universidad de Buenos Aires. Facultad de Medicina. Instituto de BiologĂa Celular y Neurociencia; ArgentinaFil: Acuña, Andres. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Oficina de CoordinaciĂłn Administrativa Houssay. Instituto de BiologĂa Celular y Neurociencia "Prof. Eduardo de Robertis". Universidad de Buenos Aires. Facultad de Medicina. Instituto de BiologĂa Celular y Neurociencia; ArgentinaFil: Soliño, Manuel. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Oficina de CoordinaciĂłn Administrativa Houssay. Instituto de BiologĂa Celular y Neurociencia "Prof. Eduardo de Robertis". Universidad de Buenos Aires. Facultad de Medicina. Instituto de BiologĂa Celular y Neurociencia; ArgentinaFil: LĂłpez Costa, Juan JosĂ©. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Oficina de CoordinaciĂłn Administrativa Houssay. Instituto de BiologĂa Celular y Neurociencia "Prof. Eduardo de Robertis". Universidad de Buenos Aires. Facultad de Medicina. Instituto de BiologĂa Celular y Neurociencia; ArgentinaFil: Kargieman, Lucila. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Oficina de CoordinaciĂłn Administrativa Ciudad Universitaria. Instituto de FisiologĂa, BiologĂa Molecular y Neurociencias. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de FisiologĂa, BiologĂa Molecular y Neurociencias; ArgentinaFil: Loidl, Cesar Fabian. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Oficina de CoordinaciĂłn Administrativa Houssay. Instituto de BiologĂa Celular y Neurociencia "Prof. Eduardo de Robertis". Universidad de Buenos Aires. Facultad de Medicina. Instituto de BiologĂa Celular y Neurociencia; Argentin
Identification and Verification of Security Relevant Functions in Embedded Systems Based on Source Code Annotations and Assertions
Annotation-Based Static Analysis for Personal Data Protection
This paper elaborates the use of static source code analysis in the context
of data protection. The topic is important for software engineering in order
for software developers to improve the protection of personal data during
software development. To this end, the paper proposes a design of annotating
classes and functions that process personal data. The design serves two primary
purposes: on one hand, it provides means for software developers to document
their intent; on the other hand, it furnishes tools for automatic detection of
potential violations. This dual rationale facilitates compliance with the
General Data Protection Regulation (GDPR) and other emerging data protection
and privacy regulations. In addition to a brief review of the state-of-the-art
of static analysis in the data protection context and the design of the
proposed analysis method, a concrete tool is presented to demonstrate a
practical implementation for the Java programming language
Enforcing Programming Guidelines with Region Types and Effects
We present in this paper a new type and effect system for Java which can be
used to ensure adherence to guidelines for secure web programming. The system
is based on the region and effect system by Beringer, Grabowski, and Hofmann.
It improves upon it by being parametrized over an arbitrary guideline supplied
in the form of a finite monoid or automaton and a type annotation or mockup
code for external methods. Furthermore, we add a powerful type inference based
on precise interprocedural analysis and provide an implementation in the Soot
framework which has been tested on a number of benchmarks including large parts
of the Stanford SecuriBench.Comment: long version of APLAS'17 pape
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