A Formal Framework for Modeling Trust and Reputation in Collective Adaptive Systems

Trust and reputation models for distributed, collaborative systems have been studied and applied in several domains, in order to stimulate cooperation while preventing selfish and malicious behaviors. Nonetheless, such models have received less attention in the process of specifying and analyzing formally the functionalities of the systems mentioned above. The objective of this paper is to define a process algebraic framework for the modeling of systems that use (i) trust and reputation to govern the interactions among nodes, and (ii) communication models characterized by a high level of adaptiveness and flexibility. Hence, we propose a formalism for verifying, through model checking techniques, the robustness of these systems with respect to the typical attacks conducted against webs of trust.Comment: In Proceedings FORECAST 2016, arXiv:1607.0200

Poor peer work does not boost student confidence

Students' low confidence, particularly in numerical topics, is thought to be a barrier to keeping them engaged with education. We studied the effects on confidence of exposure to a peer's work of varying quality (very good or bad) and neatness (messy or neat). Previous research underpinned our hypothesis that a peer's bad-quality work—which students rarely see—might boost student confidence more than very good work. We also predicted that a peer's very good work—which students are often shown—might be less discouraging if it were messy, suggesting it required effort and struggle. However, in experiments with university students and low-educated adults, these hypotheses were not supported, and all participants decreased in confidence after seeing any peer work. The failure to find support for these hypotheses can inform future research into social comparison effects on self-confidence in numerical topics. These results also have practical implications for teachers and managers who are expected to provide examples of peer work

On the Dirac Structure of the Nucleon Selfenergy in Nuclear Matter

The relativistic structure of the self-energy of a nucleon in nuclear matter is investigated including the imaginary and real components which arise from the terms of first and second order in the NN interaction. A parameterized form of Brueckner $G$ matrix is used for the NN interaction. The effects of the terms beyond the DBHF approximation on quasiparticle energies and the optical potential for nucleon-nucleus scattering are discussed.Comment: 18 pages, Latex including 10 figures using psfi

Do large language models solve verbal analogies like children do?

Analogy-making lies at the heart of human cognition. Adults solve analogies such as \textit{Horse belongs to stable like chicken belongs to ...?} by mapping relations (\textit{kept in}) and answering \textit{chicken coop}. In contrast, children often use association, e.g., answering \textit{egg}. This paper investigates whether large language models (LLMs) solve verbal analogies in A:B::C:? form using associations, similar to what children do. We use verbal analogies extracted from an online adaptive learning environment, where 14,002 7-12 year-olds from the Netherlands solved 622 analogies in Dutch. The six tested Dutch monolingual and multilingual LLMs performed around the same level as children, with MGPT performing worst, around the 7-year-old level, and XLM-V and GPT-3 the best, slightly above the 11-year-old level. However, when we control for associative processes this picture changes and each model's performance level drops 1-2 years. Further experiments demonstrate that associative processes often underlie correctly solved analogies. We conclude that the LLMs we tested indeed tend to solve verbal analogies by association with C like children do

Inhibition of HIV-1 by multiple siRNAs expressed from a single microRNA polycistron

RNA interference (RNAi) is a powerful approach to inhibit human immunodeficiency virus type 1 (HIV-1) replication. However, HIV-1 can escape from RNAi-mediated antiviral therapy by selection of mutations in the targeted sequence. To prevent viral escape, multiple small interfering RNAs (siRNAs) against conserved viral sequences should be combined. Ideally, these RNA inhibitors should be expressed simultaneously from a single transgene transcript. In this study, we tested a multiplex microRNA (miRNA) expression strategy by inserting multiple effective anti-HIV siRNA sequences in the miRNA polycistron mir-17-92. Individual anti-HIV miRNAs that resemble the natural miRNA structures were optimized by varying the siRNA position in the hairpin stem to obtain maximal effectiveness against luciferase reporters and HIV-1. We show that an antiviral miRNA construct can have a greater intrinsic inhibitory activity than a conventional short hairpin (shRNA) construct. When combined in a polycistron setting, the silencing activity of an individual miRNA is strongly boosted. We demonstrate that HIV-1 replication can be efficiently inhibited by simultaneous expression of four antiviral siRNAs from the polycistronic miRNA transcript. These combined results indicate that a multiplex miRNA strategy may be a promising therapeutic approach to attack escape-prone viral pathogens

Analgesic Mechanism of Electroacupuncture in an Arthritic Pain Model of Rats: A Neurotransmitter Study

Yonsei University College of Medicine 2011 This is an Open Access article distributed under the terms of the Creative Commons Attribution Non-Commercial Licens

RNAi-mediated inhibition of HIV-1 by targeting partially complementary viral sequences

Potent antiviral RNAi can be induced by intracellular expression of short hairpin RNAs (shRNAs) and artificial microRNAs (miRNAs). Expression of shRNA and miRNA results in target mRNA degradation (perfect base pairing) or translational repression (partial base pairing). Although efficient inhibition can be obtained, error-prone viruses such as human immunodeficiency virus type 1 (HIV-1) can escape from RNAi-mediated inhibition by mutating the target sequence. Recently, artificial miRNAs have been shown to be potent RNAi inducers due to their efficient processing by the RNAi machinery. Furthermore, miRNAs may be more proficient in suppressing imperfect targets than shRNAs. In this study, we tested the knockdown efficiency of miRNAs and shRNAs against wild-type and RNAi-escape HIV-1 variants with one or two mutations in the target sequence. ShRNAs and miRNAs can significantly inhibit the production of HIV-1 variants with mutated target sequences in the open reading frame. More pronounced mutation-tolerance was measured for targets in the 3′ untranslated region (3′ UTR). Partially complementary sequences within the 3′ UTR of the HIV-1 RNA genome efficiently act as target sites for miRNAs and shRNAs. These data suggest that targeting imperfect target sites by antiviral miRNAs or shRNAs provides an alternative RNAi approach for inhibition of pathogenic viruses

Hyperbaric oxygen therapy improves colorectal anastomotic healing

Purpose: Hyperbaric oxygen treatment (HBOT) has been found to improve the healing of poorly oxygenated tissues. This study aimed to investigate the influence of HBOT on the healing in ischemic colorectal anastomosis. Methods: Forty Wistar rats were randomly divided into a treatment group that received HBOT for 10 consecutive days (7 days before and 3 days after surgery), or in a control group, which did not receive the therapy. Colectomy with an ischemic anastomosis was performed in all rats. In each group, the rats were followed for 3 or 7 days after surgery to determine the influence of HBOT on anastomotic healing. Results: Five rats from each group died during follow-up. No anastomotic dehiscence was seen in the HBOT group, compared to 37.5 % and 28.6 % dehiscence in the control group on postoperative day (POD) 3 and 7, respectively. The HBOT group had a significantly higher bursting pressure (130.9 ± 17.0 mmHg) than the control group (88.4 ± 46.7 mmHg; p = 0.03) on POD 3. On POD 3 and POD 7, the adhesion severity was significantly higher in the control groups than in the HBOT groups (p < 0.005). Kidney function (creatinine level) of the HBOT group was significantly better than of the control group on POD 7 (p = 0.001). Interestingly, a significantly higher number of CD206+ cells (marker for type 2 macrophages) was observed in the HBOT group at the anastomotic area on POD 3. Conclusion: Hyperbaric oxygen enhanced the healing of ischemic anastomoses in rats and improved the postoperative kidney function

Short Enantioselective Total Synthesis of Tatanan A and 3-epi-Tatanan A Using Assembly-Line Synthesis

Short and highly stereoselective total syntheses of the sesquilignan natural product tatanan A and its C3 epimer are described. An assembly-line synthesis approach, using iterative lithiation–borylation reactions, was applied to install the three contiguous stereocenters with high enantio- and diastereoselectivity. One of the stereocenters was installed using a configurationally labile lithiated primary benzyl benzoate, resulting in high levels of substrate-controlled (undesired) diastereoselectivity. However, reversal of selectivity was achieved by using a novel diastereoselective Matteson homologation. Stereospecific alkynylation of a hindered secondary benzylic boronic ester enabled completion of the synthesis in a total of eight steps