| 1. |
- Aranäs, Cajsa, et al.
(författare)
-
Salmon Calcitonin Attenuates Some Behavioural Responses to Nicotine in Male Mice
- 2021
-
Ingår i: Frontiers in Pharmacology. - : Frontiers Media SA. - 1663-9812. ; 12
-
Tidskriftsartikel (refereegranskat)abstract
- The behavioural responses to nicotine involve appetite-regulatory hormones; however, the effects of the anorexigenic hormone amylin on reward-related behaviours induced by nicotine remain to be established. Previous studies have shown that the amylinergic pathway regulates behavioural responses to alcohol, amphetamine and cocaine. Here, we evaluated the effects of salmon calcitonin (sCT), an amylin and calcitonin receptor (CTR) agonist, on nicotine-induced locomotor stimulation and sensitisation as well as dopamine release in the nucleus accumbens (NAc) shell. Moreover, we investigated the effects of sCT on the acquisition and expression of nicotine-induced reward in the conditioned place preference (CPP) paradigm. Finally, we performed Western Blot experiments in an attempt to identify the levels of the amylin receptor components CTRa, CTRb, and RAMP1 in reward-related areas of mice responding differently to repeated injections of sCT and nicotine in the locomotor sensitisation test. We found that sCT blocked nicotine's stimulatory and dopamine-releasing effects and prevented its ability to cause locomotor sensitisation. On the other hand, sCT did not alter nicotine-induced acquisition and expression of CPP. Lastly, sCT-nicotine treated mice from the locomotor sensitisation experiment displayed higher levels of total CTR, i.e. CTRa and CTRb together, in the reward-processing laterodorsal tegmental area (LDTg) of the brain compared to mice treated with vehicle-nicotine. Overall, the present data reveal that activation of CTR or/and amylin receptors attenuates certain nicotine-induced behaviours in male mice, further contributing to the understanding of appetite-regulatory peptides in reward regulation.
|
|
| 2. |
- Edvardsson, Christian, et al.
(författare)
-
A ghrelin receptor antagonist reduces the ability of ghrelin, alcohol or amphetamine to induce a dopamine release in the ventral tegmental area and in nucleus accumbens shell in rats
- 2021
-
Ingår i: European Journal of Pharmacology. - : Elsevier BV. - 0014-2999. ; 899
-
Tidskriftsartikel (refereegranskat)abstract
- The orexigenic peptide ghrelin increases the release of dopamine in the nucleus accumbens (NAc) shell via central ghrelin receptors, especially those located in the ventral tegmental area (VTA). The activity of the VTA dopamine neurons projecting to NAc shell, involves somatodendritic dopamine release within the VTA. However, the effects of ghrelin on the concomitant dopamine release in the VTA and NAc shell is unknown. It is further unknown whether addictive drugs, such as alcohol and amphetamine, enhance the dopamine levels in both these areas via ghrelin receptor dependent mechanisms. Thus, the effects of a ghrelin receptor antagonist, JMV2959, on the ability of i) central ghrelin ii) systemic alcohol or iii) systemic amphetamine to increase the dopamine release in the VTA and in the NAc shell in rats by using in vivo microdialysis was explored. We showed that systemic administration of JMV2959 blocks the ability of central ghrelin to increases dopamine release in the VTA and the NAc shell, and reduces the alcohol- and amphetamine-induced dopamine release in both these areas. Locomotor activity studies was then conducted in an attempt to correlate the ghrelin-induced dopamine release in the VTA to a behavioural outcome. These revealed that local infusion of a dopamine D1 receptor antagonist into the VTA blocks the ability of central ghrelin to cause a locomotor stimulation in mice. Collectively, this study adds to the growing body of evidence indicating that ghrelin signalling modulates the ability of ghrelin, and addictive drugs, to activate the mesoaccumbal dopamine pathway.
|
|
| 3. |
- Gil Gómez, Gaspar, et al.
(författare)
-
Improving subjective assessments of vehicle dynamics evaluations by means of computer tablets as digital aid
- 2016
-
Ingår i: Computer software and hardware. - 400 Commonwealth Drive, Warrendale, PA, United States : SAE International.
-
Konferensbidrag (refereegranskat)abstract
- Vehicle dynamics development relies on subjective assessments (SA), which is a resource-intensive procedure requiring both expert drivers and vehicles. Furthermore, development projects becoming shorter and more complex, and increasing demands on quality require higher efficiency.Most research in this area has focused on moving from physical to virtual testing. However, SA remains the central method. Less attention has been given to provide better tools for the SA process itself. One promising approach is to introduce computer-tablets to aid data collection, which has proven to be useful in medical studies. Simple software solutions can eliminate the need to transcribe data and generate more flexible and better maintainable questionnaires. Tablets’ technical features envision promising enhancements of SA, which also enable better correlations to objective metrics, a requirement to improve CAE evaluations.However, it cannot be assumed that a tablet-based solution is feasible in vehicle dynamics SA context. Any distraction might result in low SA quality and safety issues when test-drivers are subjected to high mental workload pushing the vehicles to their performance-limits.In this study, a SA tablet-software for steering feel, handling, and ride was developed and systematically evaluated versus the traditional pen-and-paper method. The results indicate that the new approach is technically feasible in this context, meets more use-cases, and the drivers’ attitude towards it is positive. It increased questionnaire completion and rating resolution while reducing the error rate and transcription time.Although attendees reported that the paper-based approach has advantages from a usability point of view, the benefits of the tablet-based approach enable further process-related advantages.
|
|
| 4. |
- Grimsdal, Gunnar, et al.
(författare)
-
Can Microkernels Mitigate Microarchitectural Attacks?
- 2019
-
Ingår i: Secure IT Systems. - Cham : Springer. - 9783030350543 - 9783030350550 ; , s. 238-253
-
Bokkapitel (refereegranskat)abstract
- Microarchitectural attacks such as Meltdown and Spectre have attracted much attention recently. In this paper we study how effective these attacks are on the Genode microkernel framework using three different kernels, Okl4, Nova, and Linux. We try to answer the question whether the strict process separation provided by Genode combined with security-oriented kernels such as Okl4 and Nova can mitigate microarchitectural attacks. We evaluate the attack effectiveness by measuring the throughput of data transfer that violates the security properties of the system. Our results show that the underlying side-channel attack Flush+Reload used in both Meltdown and Spectre, is effective on all investigated platforms. We were also able to achieve high throughput using the Spectre attack, but we were not able to show any effective Meltdown attack on Okl4 or Nova.
|
|
| 5. |
- Hasselquist, David, et al.
(författare)
-
Twitch Chat Fingerprinting
- 2022
-
Ingår i: Proc. IFIP Network Traffic Measurement and Analysis Conference (TMA) 2022.
-
Konferensbidrag (refereegranskat)abstract
- The streaming content that we choose to watch canreveal much about our thoughts, opinions, and interests. Anadversary capable of determining what users watch thereforepresents a significant privacy threat. In this paper, we presentand evaluate the first fingerprinting attack on Twitch that allowsviewers of individual live streams to be identified despite thetraffic being encrypted. The attack targets the traffic patternsassociated with chat messages associated with each stream. Ourresults show that high accuracy can be achieved by eavesdroppingonly for a short time (e.g., 90 seconds) and that the accuracy canbe increased even further by interacting with the stream. We alsotake a closer look at how the accuracy and activity level differbetween different Twitch channels and provide insights into theaccuracy that attackers using different strategies for selectingtarget channels may have. Finally, we study countermeasures toprotect against such attacks and demonstrate that the naive use ofVPN is not enough. We instead present countermeasures alteringpacket timing and sizes. Our large-scale evaluation of differentcountermeasures provides important insights that help both thestreaming providers and users better protect their privacy.
|
|
| 6. |
- Usman, Ahmad, et al.
(författare)
-
Remote Attestation Assurance Arguments for Trusted Execution Environments
- 2023
-
Ingår i: PROCEEDINGS OF THE 2023 ACM WORKSHOP ON SECURE AND TRUSTWORTHY CYBER-PHYSICAL SYSTEMS, SAT-CPS 2023. - : ASSOC COMPUTING MACHINERY. - 9798400701009 ; , s. 33-42
-
Konferensbidrag (refereegranskat)abstract
- Remote attestation (RA) is emerging as an important security mechanism for cyber-physical systems with strict security requirements. Trusted computing at large and Trusted Execution Environments (TEEs) in particular have been identified as key technologies to enable RA since they ideally allow retaining some element of control over remote devices despite them being compromised at the OS level. Unfortunately, sometimes it is claimed that TEEs provide RA support without really substantiating how this support is provided. In this paper we build the assurance arguments for RA to carefully map how secure RA depends on underlying security properties and how these in turn can be provided by TEE capabilities. We base our security analysis of RA on existing literature on security requirements for RA and use Goal Structuring Notation (GSN) as the method to build the security arguments. Our analysis identifies the set of TEE properties (as described in the GlobalPlatform standard) that are needed to support RA, and which goals that cannot be mapped to TEE implementations, and therefore, require other forms of evidence for RA to be trusted at the top level.
|
|
