Dyslexics are diagnosed for their poor reading skills. Yet they characteristically also suffer from poor verbal memory, and often from poor auditory skills. To date, this combined profile has been accounted for in broad cognitive terms. Here, we hypothesize that the perceptual deficits associated with dyslexia can be understood computationally as a deficit in integrating prior information with noisy observations. To test this hypothesis we analyzed the performance of human participants in an auditory discrimination task using a two-parameter computational model. One parameter captures the internal noise in representing the current event, and the other captures the impact of recently acquired prior information. Our findings show that dyslexics perceptual deficit can be accounted for by inadequate adjustment of these components; namely, low weighting of their implicit memory of past trials relative to their internal noise. Underweighting the stimulus statistics decreased dyslexics ability to compensate for noisy observations. ERP measurements (P2 component) while participants watched a silent movie, indicated that dyslexics perceptual deficiency may stem from poor automatic integration of stimulus statistics. Taken together, this study provides the first description of a specific computational deficit associated with dyslexia.
Dyslexics are diagnosed for their poor reading skills, yet they characteristically also suffer from poor verbal memory and often from poor auditory skills. To date, this combined profile has been accounted for in broad cognitive terms. Here we hypothesize that the perceptual deficits associated with dyslexia can be understood computationally as a deficit in integrating prior information with noisy observations. To test this hypothesis we analyzed the performance of human participants in an auditory discrimination task using a two-parameter computational model. One parameter captures the internal noise in representing the current event, and the other captures the impact of recently acquired prior information. Our findings show that dyslexics' perceptual deficit can be accounted for by inadequate adjustment of these components; namely, low weighting of their implicit memory of past trials relative to their internal noise. Underweighting the stimulus statistics decreased dyslexics' ability to compensate for noisy observations. ERP measurements (P2 component) while participants watched a silent movie indicated that dyslexics' perceptual deficiency may stem from poor automatic integration of stimulus statistics. This study provides the first description of a specific computational deficit associated with dyslexia.
Reactions on water and ice surfaces and in other aqueous media are ubiquitous in the atmosphere, but the microscopic mechanisms of most of these processes are as yet unknown. This Account examines recent progress in atomistic simulations of such reactions and the insights provided into mechanisms and interpretation of experiments. Illustrative examples are discussed. The main computational approaches employed are classical trajectory simulations using interaction potentials derived from quantum chemical methods. This comprises both ab initio molecular dynamics (AIMD) and semiempirical molecular dynamics (SEMD), the latter referring to semiempirical quantum chemical methods. Presented examples are as follows: (i) Reaction of the (NO+)(NO3-) ion pair with a water cluster to produce the atmospherically important HONO and HNO3. The simulations show that a cluster with four water molecules describes the reaction. This provides a hydrogen-bonding network supporting the transition state. The reaction is triggered by thermal structural fluctuations, and ultrafast changes in atomic partial charges play a key role. This is an example where a reaction in a small cluster can provide a model for a corresponding bulk process. The results support the proposed mechanism for production of HONO by hydrolysis of NO2 (N2O4). (ii) The reactions of gaseous HCl with N2O4 and N2O5 on liquid water surfaces. Ionization of HCl at the water/air interface is followed by nucleophilic attack of Cl on N2O4 or N2O5. Both reactions proceed by an SN2 mechanism. The products are ClNO and ClNO2, precursors of atmospheric atomic chlorine. Because this mechanism cannot result from a cluster too small for HCl ionization, an extended water film model was simulated. The results explain ClNO formation experiments. Predicted ClNO2 formation is less efficient. (iii) Ionization of acids at ice surfaces. No ionization is found on ideal crystalline surfaces, but the process is efficient on isolated defects where it involves formation of H3O+-acid anion contact ion pairs. This behavior is found in simulations of a model of the ice quasi-liquid layer corresponding to large defect concentrations in crystalline ice. The results are in accord with experiments. (iv) Ionization of acids on wet quartz. A monolayer of water on hydroxylated silica is ordered even at room temperature, but the surface lattice constant differs significantly from that of crystalline ice. The ionization processes of HCl and H2SO4 are of high yield and occur in a few picoseconds. The results are in accord with experimental spectroscopy. (v) Photochemical reactions on water and ice. These simulations require excited state quantum chemical methods. The electronic absorption spectrum of methyl hydroperoxide adsorbed on a large ice cluster is strongly blue-shifted relative to the isolated molecule. The measured and calculated adsorption band low-frequency tails are in agreement. A simple model of photodynamics assumes prompt electronic relaxation of the excited peroxide due to the ice surface. SEMD simulations support this, with the important finding that the photochemistry takes place mainly on the ground state. In conclusion, dynamics simulations using quantum chemical potentials are a useful tool in atmospheric chemistry of water media, capable of comparison with experiment.
Classically, risk aversion is equated with concavity of the utility function. In this work we explore the conceptual foundations of this definition. In accordance with neo-classical economics, we seek an ordinal definition, based on the decisions maker s preference order, independent of numerical values. We present two such definitions, based on simple, conceptually appealing interpretations of the notion of risk-aversion. We then show that when cast in quantitative form these ordinal definitions coincide with the classical Arrow-Pratt definition (once the latter is defined with respect to the appropriate units), thus providing a conceptual foundation for the classical definition. The implications of the theory are discussed, including, in particular, to the understanding of insurance. The entire study is within the expected utility framework.
While recent literature reports that network diversity generates tolerance, empirical data suggest that in Israel, a highly diverse country, tolerance has been in scarce supply. The well-documented importance of personal value preferences (specifically, openness to change vs. conservation and self-transcendence vs. self-enhancement) in producing tolerant views leads us to hypothesize that values function as boundary conditions mitigating the impact of network diversity upon both political and social tolerance. Building on a representative survey conducted in Israel in 2011, we show that diversity contributes to tolerance more when people are open-minded; when conservatives encounter dissimilar attitudes, they are either less affected or respond with increased intolerance. Secondly, those who highly regard the opinions of others and express an individual predisposition for self-transcendence at the expense of self-enhancement are affected by network diversity to a greater extent. Further, the effect of diversity on tolerance is mediated by the perceived threat from the relevant group.
The article considers Israel Zangwill’s Children of the Ghetto through the lens of two late-nineteenth century photographic techniques: hinged-mirror and composite photography. These two techniques, each of which played a role in Zangwill’s personal life, can help to reframe Zangwill’s personal and literary struggles with representations of Jewish identity that were confined to notions of “types,” or stereotypes, of race and ethnicity. The article traces Zangwill’s overall discomfort with what it terms the “composite photographic logic of liberalism,” a logic that predicated tolerance on the radical assimilation of Jewish difference and reinforced institutional practices of Anglicization, especially in London’s East End Ghetto.
January 2015: Amanda Sharick is a Ph.D. candidate in English at the University of California, Riverside. She specializes in late-nineteenth British and related literatures, Victorian media and visual culture, Jewish Studies, gender studies, and immigrant literature. Her dissertation traces the transatlantic networks of Anglo and American Jewish women writers from 1880–1918.
Maurice Ebileeni explores the thematic and stylistic problems in the major novels of Joseph Conrad and William Faulkner through Jacques Lacan's psychoanalytic theories. Against the background of the cultural, scientific, and historic changes that occurred at the turn of the 20th century, describing the landscape of ruins bequeathed to humanists by the forefathers of the Counter-Enlightenment movement (Schopenhauer, Kierkegaard, Nietzsche, Dostoyevsky, and Baudelaire), Ebileeni proposes that Conrad and Faulkner wrote against impossible odds, metaphorically standing at the edge of a chaotic abyss that initially would spill over into the challenges of literary production. Both authors discovered that underneath, behind, or within the intuitively comprehensible narrative layers there exists a nonsensical dimension, constantly threatening to dissolve any attempt at producing intelligible meaning.Ebileeni argues that in Conrad's and Faulkner's major novels, the quest for meaning in confronting the prospects of nonsense becomes a necessary symptom of human experience to both avoid and engage the entropy of modern life.(New York: Bloomsbury Academic, 2015)
In spite of a pronounced increase in the number of states that have adopted anti-defection laws over the past several decades, the literature on party unity in democratic legislatures has paid scant attention to understanding the conditions that lead to the adoption of such restrictive measures on the mobility of elected deputies. This article seeks to fill this gap. The authors provide a simple game-theoretic model to explain the passage of anti-defection measures in India, in 1985, and Israel, in 1991. These two democratic states were among the first to experiment with the constitutionalisation of anti-defection measures. Moreover, their comparison is important because although these laws were adopted under seemingly very different circumstances, they were supported with a strong consensus by both the government party, or coalition, and the opposition. It is argued that the reasons for the passage of the anti-defection laws in these two states were rooted in the strategic consequences of the changes that took place in the format of their party systems. The Indian and the Israeli cases show, respectively, that a dominant party system (India) and a tightly balanced bipolar party system (Israel) provided equally compelling incentives for rampant party switching between government and opposition, which therefore created an incentive for both sides to agree to, and adopt, a strict legislative measure to curb defections. [ABSTRACT FROM PUBLISHER]Copyright of Journal of Legislative Studies is the property of Routledge and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder’s express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)
An approach to construct enantiopure complex natural product-like frameworks, including the first reported synthesis of a C17 oxygenated taxoid scaffold, is presented. A palladium-catalyzed C–C activation/cross-coupling is utilized to access these structures in a short sequence from (+)-carvone; the scope of this reaction is explored.
An approach to construct enantiopure complex natural product-like frameworks, including the first reported synthesis of a C17 oxygenated taxoid scaffold, is presented. A palladium-catalyzed C–C activation/cross-coupling is utilized to access these structures in a short sequence from (+)-carvone; the scope of this reaction is explored.
A generic methodology for constructing complex integrated electro-optic circuits in waveguided configurations is presented. The method is based on combining two techniques, ’laser ablation’ and ’refractive index engineering by ion implantations.’ The constructed circuits are side-cladded by air trenches that were produced using laser ablation and bottom-cladded by a layer with a reduced refractive index which is generated through the implantation of He.sup.+ ions. This fabrication technique enables the construction of circular structures with complex geometry featuring small radii of curvature, and further can be employed to construct microfluidic channels on the same substrate. The research demonstrates waveguides in both linear and circular configurations that were constructed in a potassium lithium tantalate niobate (KLTN) substrate using the aforementioned method, proving that this substrate is a suitable candidate for use in creating laboratories-on-a-chip with multifunctional capabilities. The proposed techniques used in the research are generic and applicable to a wide range of substrates.
D Pierangeli, Flammini, M. , Di Mei, F , Parravicini, J. , de Oliveira, C.E.M. , Agranat, A.J. , ו Del Re, E.. 2015. “Continuous Solitons In Lattice Nonlinearity”. Phys. Rev. Lett, 114, Pp. 203901.
Hindbrain dorsal interneurons (HDIs) are implicated in receiving, processing, integrating, and transmitting sensory inputs from the periphery and spinal cord, including the vestibular, auditory, and proprioceptive systems. During development, multiple molecularly defined HDI types are set in columns along the dorsoventral axis, before migrating along well-defined trajectories to generate various brainstem nuclei. Major brainstem functions rely on the precise assembly of different interneuron groups and higher brain domains into common circuitries. Yet, knowledge regarding interneuron axonal patterns, synaptic targets, and the transcriptional control that govern their connectivity is sparse. The dB1 class of HDIs is formed in a district dorsomedial position along the hindbrain and gives rise to the inferior olive nuclei, dorsal cochlear nuclei, and vestibular nuclei. dB1 interneurons express various transcription factors (TFs): the pancreatic transcription factor 1a (Ptf1a), the homeobox TF-Lbx1 and the Lim-homeodomain (Lim-HD), and TF Lhx1 and Lhx5. To decipher the axonal and synaptic connectivity of dB1 cells, we have used advanced enhancer tools combined with conditional expression systems and the PiggyBac-mediated DNA transposition system in avian embryos. Multiple ipsilateral and contralateral axonal projections were identified ascending toward higher brain centers, where they formed synapses in the Purkinje cerebellar layer as well as at discrete midbrain auditory and vestibular centers. Decoding the mechanisms that instruct dB1 circuit formation revealed a fundamental role for Lim-HD proteins in regulating their axonal patterns, synaptic targets, and neurotransmitter choice. Together, this study provides new insights into the assembly and heterogeneity of HDIs connectivity and its establishment through the central action of Lim-HD governed programs.
