11 research outputs found
Consensus in Equilibrium: Can One Against All Decide Fairly?
Is there an equilibrium for distributed consensus when all agents except one collude to steer the decision value towards their preference? If an equilibrium exists, then an n-1 size coalition cannot do better by deviating from the algorithm, even if it prefers a different decision value. We show that an equilibrium exists under this condition only if the number of agents in the network is odd and the decision is binary (among two possible input values). That is, in this framework we provide a separation between binary and multi-valued consensus. Moreover, the input and output distribution must be uniform, regardless of the communication model (synchronous or asynchronous). Furthermore, we define a new problem - Resilient Input Sharing (RIS), and use it to find an iff condition for the (n-1)-resilient equilibrium for deterministic binary consensus, essentially showing that an equilibrium for deterministic consensus is equivalent to each agent learning all the other inputs in some strong sense. Finally, we note that (n-2)-resilient equilibrium for binary consensus is possible for any n. The case of (n-2)-resilient equilibrium for multi-valued consensus is left open
Hemispheric asymmetries in semantic processing: Evidences from false memories for ambiguous words
Abstract Previous research suggests that the left hemisphere (LH) focuses on strongly related word meanings; the right hemisphere (RH) may contribute uniquely to the processing of lexical ambiguity by activating and maintaining a wide range of meanings, including subordinate meanings. The present study used the word-lists false memory paradigm [Roediger, H. L. III., & McDermott, K. B. (1995). Creating false memories: Remembering words not presented in lists. Journal of Experimental Psychology: Learning, Memory, and Cognition, 21, 803-814.] to examine whether these differences between the two cerebral hemispheres in semantic processing also affect memory representations for different meanings of ambiguous words. Specifically, we tested the differences between the LH and RH in recollecting unpresented, semantically related, ambiguous words following the presentation of lists of words all related to either the dominant or the subordinate meanings of these ambiguous words. Findings showed that for the unpresented ambiguous words, the LH made more false alarms than the RH for the dominant lists, whereas the opposite pattern emerged for subordinate lists. Moreover, d 0 analyses showed that, whereas the LH was more sensitive to subordinate than dominant meanings, the RH showed no differences in sensitivity for the two types of word-lists. Taken as a whole, these results support the RH coarse semantic coding theory [Beeman, M. (1998) , 9, 512-518.] indicating that during word recognition, the RH activates and maintains a broader and less differentiated range of related meanings than the LH, including both dominant and subordinate meanings of ambiguous words. Furthermore, the findings suggest that hemispheric differences in ambiguity resolution during language processing extend also to verbal memory
A Simple Method to Characterize Twin Boundary Kinetics in Ni-Mn-Ga
Magnetic Shape Memory (MSM) alloys are an extraordinary class of smart materials that can deform via twinning under relatively mild magnetic field (\u3c 1 T). As such, characterization of twin boundary kinetics is essential to systematically reproduce the actuation properties of MSM elements. Here we present a relatively simple method to measure the transitional driving force (go) beyond which the twin boundary motion is extremely fast (\u3e0.5 m/s)
Repetitive Transcranial Magnetic Stimulation in Alcohol Dependence : A Randomized, Double-Blind, Sham-Controlled Proof-of-Concept Trial Targeting the Medial Prefrontal and Anterior Cingulate Cortices
BACKGROUND: Alcohol addiction is associated with a high disease burden, and treatment options are limited. In a proof-of-concept study, we used deep repetitive transcranial magnetic stimulation (dTMS) to target circuitry associated with the pathophysiology of alcohol addiction. We evaluated clinical outcomes and explored associated neural signatures using functional magnetic resonance imaging. METHODS: This was a double-blind, randomized, sham-controlled trial. A total of 51 recently abstinent treatment-seeking patients with alcohol use disorder (moderate to severe) were randomized to sham or active dTMS, using an H7 coil targeting midline frontocortical areas, including the medial prefrontal and anterior cingulate cortices. Treatment included 15 sessions over 3 weeks, followed by five sessions over 3 months of follow-up. Each session delivered 100 trains of 30 pulses at 10 Hz. The primary predefined outcome was reduction in percentage of heavy drinking days, obtained using timeline follow-back interviews. Secondary analyses included self-reports of craving, ethyl glucuronide in urine, and brain imaging measures. RESULTS: Both craving after treatment and percentage of heavy drinking days during follow-up were significantly lower in the active versus sham control group (percentage of heavy drinking days = 2.9 +/- 0.8% vs. 10.6 +/- 1.9%, p = .037). Active dTMS was associated with decreased resting-state functional connectivity of the dorsal anterior cingulate cortex with the caudate nucleus and decreased connectivity of the medial prefrontal cortex to the subgenual anterior cingulate cortex. CONCLUSIONS: We provide initial proof-of-concept for dTMS targeting midline frontocortical structures as a treatment for alcohol addiction. These data strongly support a rationale for a full-scale confirmatory multicenter trial. Therapeutic benefits of dTMS appear to be associated with persistent changes in brain network activity.Funding Agencies|European Union [668863-SyBil-AA]; Swedish Research Council [2013-07434]</p
UMSBP2 is chromatin remodeler that functions in regulation of gene expression and suppression of antigenic variation in trypanosomes
Universal Minicircle Sequence binding proteins (UMSBPs) are CCHC-type zinc-finger proteins that bind the single-stranded G-rich UMS sequence, conserved at the replication origins of minicircles in the kinetoplast DNA, the mitochondrial genome of kinetoplastids. Trypanosoma brucei UMSBP2 has been recently shown to colocalize with telomeres and to play an essential role in chromosome end protection. Here we report that TbUMSBP2 decondenses in vitro DNA molecules, which were condensed by core histones H2B, H4 or linker histone H1. DNA decondensation is mediated via protein-protein interactions between TbUMSBP2 and these histones, independently of its previously described DNA binding activity. Silencing of the TbUMSBP2 gene resulted in a significant decrease in the disassembly of nucleosomes in T. brucei chromatin, a phenotype that could be reverted, by supplementing the knockdown cells with TbUMSBP2. Transcriptome analysis revealed that silencing of TbUMSBP2 affects the expression of multiple genes in T. brucei, with a most significant effect on the upregulation of the subtelomeric variant surface glycoproteins (VSG) genes, which mediate the antigenic variation in African trypanosomes. These observations suggest that UMSBP2 is a chromatin remodeling protein that functions in the regulation of gene expression and plays a role in the control of antigenic variation in T. brucei.Fil: Soni, Awakash. The Hebrew University of Jerusalem; IsraelFil: Klebanov Akopyan, Olga. The Hebrew University of Jerusalem; IsraelFil: Erben, Esteban Daniel. Universidad Nacional de San MartÃn. Instituto de Investigaciones Biotecnológicas. - Consejo Nacional de Investigaciones CientÃficas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Investigaciones Biotecnológicas; Argentina. Ruprecht Karls Universitat Heidelberg; AlemaniaFil: Plaschkes, Inbar. The Hebrew University of Jerusalem; IsraelFil: Benyamini, Hadar. The Hebrew University of Jerusalem; IsraelFil: Mitesser, Vera. The Hebrew University of Jerusalem; IsraelFil: Harel, Amnon. Bar-Ilan University; IsraelFil: Yamin, Katereena. Bar-Ilan University; IsraelFil: Onn, Itay. Bar-Ilan University; IsraelFil: Shlomai, Joseph. The Hebrew University of Jerusalem; Israe
Deciphering genetic factors that determine melon fruit-quality traits using RNA-Seq-based high-resolution QTL and eQTL mapping
Combined quantitative trait loci (QTL) and expression-QTL (eQTL) mapping analysis was performed to identify genetic factors affecting melon (Cucumis melo) fruit quality, by linking genotypic, metabolic and transcriptomic data from a melon recombinant inbred line (RIL) population. RNA sequencing (RNA-Seq) of fruit from 96 RILs yielded a highly saturated collection of >58000 single-nucleotide polymorphisms, identifying 6636 recombination events that separated the genome into 3663 genomic bins. Bin-based QTL analysis of 79 RILs and 129 fruit-quality traits affecting taste, aroma and color resulted in the mapping of 241 QTL. Thiol acyltransferase (CmThAT1) gene was identified within the QTL interval of its product, S-methyl-thioacetate, a key component of melon fruit aroma. Metabolic activity of CmThAT1-encoded protein was validated in bacteria and invitro. QTL analysis of flesh color intensity identified a candidate white-flesh gene (CmPPR1), one of two major loci determining fruit flesh color in melon. CmPPR1 encodes a member of the pentatricopeptide protein family, involved in processing of RNA in plastids, where carotenoid and chlorophyll pigments accumulate. Network analysis of >12000 eQTL mapped for >8000 differentially expressed fruit genes supported the role of CmPPR1 in determining the expression level of plastid targeted genes. We highlight the potential of RNA-Seq-based QTL analysis of small to moderate size, advanced RIL populations for precise marker-assisted breeding and gene discovery. We provide the following resources: a RIL population genotyped with a unique set of SNP markers, confined genomic segments that harbor QTL governing 129 traits and a saturated set of melon eQTLs.
Significance Statement: Fruit-quality traits of melon were studied by linking genotypic, metabolic and transcriptomic data from a recombinant inbred line population. High resolution RNA-Seq-based quantitative trait loci and expression-QTL analyses enabled the identification of two genes that affect aroma and color