Asymmetries around the visual field: From retina to cortex to behavior

Visual performance varies around the visual field. It is best near the fovea compared to the periphery, and at iso-eccentric locations it is best on the horizontal, intermediate on the lower, and poorest on the upper meridian. The fovea-to-periphery performance decline is linked to the decreases in cone density, retinal ganglion cell (RGC) density, and V1 cortical magnification factor (CMF) as eccentricity increases. The origins of polar angle asymmetries are not well understood. Optical quality and cone density vary across the retina, but recent computational modeling has shown that these factors can only account for a small percentage of behavior. Here, we investigate how visual processing beyond the cone photon absorptions contributes to polar angle asymmetries in performance. First, we quantify the extent of asymmetries in cone density, midget RGC density, and V1 CMF. We find that both polar angle asymmetries and eccentricity gradients increase from cones to mRGCs, and from mRGCs to cortex. Second, we extend our previously published computational observer model to quantify the contribution of phototransduction by the cones and spatial filtering by mRGCs to behavioral asymmetries. Starting with photons emitted by a visual display, the model simulates the effect of human optics, cone isomerizations, phototransduction, and mRGC spatial filtering. The model performs a forced choice orientation discrimination task on mRGC responses using a linear support vector machine classifier. The model shows that asymmetries in a decision maker’s performance across polar angle are greater when assessing the photocurrents than when assessing isomerizations and are greater still when assessing mRGC signals. Nonetheless, the polar angle asymmetries of the mRGC outputs are still considerably smaller than those observed from human performance. We conclude that cone isomerizations, phototransduction, and the spatial filtering properties of mRGCs contribute to polar angle performance differences, but that a full account of these differences will entail additional contribution from cortical representations.

Introduction

This publication is one of the outcomes of over a decade of work, under the auspices of the United Nations Committee on the Rights of the Child, to explore how to monitor and evaluate States Parties’ compliance with the obligations they undertook when they ratified the UN Convention on the Rights of the Child (the Convention). A full account of the project work to date has been provided in Vaghri, Krappmann, and Doek’s article ‘From the Indicators of General Comment No. 7 to GlobalChild’ (2019). Grounded in that foundational work, this book relies on that project work to provide a conceptual framing of the Convention, through the identification of the attributes of each right that provides the basis for the development of indicators against which to measure progress.

The role of the notion of a proper answer in the logic of questions

The observations in the article mainly concern the role of the concept of the so-called right answer in question logic. The purpose of these remarks is to justify the postulate that any logic of questions should be based on a conception of the structure of questions and answers, in which the notion of a proper answer is strictly defined. This postulate is addressed to any question logic, although it is mainly supported and illustrated by analyses and comparative remarks referring to concepts based on Ajdukiewicz’s question theory and to recent approaches of inferential erotetic logic (IEL). The analyses confirm that the concept of proper answer is fundamental in question theories, as it is assumed in the definitions of almost all concepts relating to questions and answers. In Ajdukiewicz’s concept, it is used explicitly, for example, in the definitions of the conditions of proper questioning and of complete and exhaustive answers. In IEL, it appears explicitly in the definitions of: the pertinent question, the notion of the presupposition of a question (and its variations), the relations of evoking a question (by a set of indicative sentences) and implying a question (by another question), etc. This basic concept should therefore be well defined. This postulate applies especially to such theories of questions in which assertions about questions and answers are proved in symbolic language – as is the case in IEL, which, however, lacks a strict definition of the concept of proper answer (there are only vague, pragmatic terms formulated in natural language). There is, however, a definition that is closer to the idea of the proper answer, adopted by Ajdukiewicz as well as in the concepts related to it, that a proper answer is one the structure of which is determined by the scheme of the question structure. However, this definition should be complemented by an accurate and general conception of question structure, which is lacking in the existing concepts. In order to confirm the validity of the formulated postulate, the article proposes new results achieved in the theory of questions, in which Ajdukiewicz’s ideas are developed and supplemented by a full account of the structure of questions and well-defined, i.e. formulated in a general and strict way as is the idea of proper answer.

On challenges to respect for autonomous decision making in primary care

Primary health care is characterised by timely and appropriate health care access, delivered continuously over time to a specific population, providing a comprehensive service, with coordination of care for those that need it. Practitioners deal with a multiplicity of clinical issues within longitudinal relationships, embedded in the context of families and communities. We propose that these aspects of primary care have a bearing on how matters of decision making are considered and implemented. Further, the standard account of autonomous decision making is not wholly adequate when applied to clinician–patient encounters in primary care. We add considerations of the impact of illness (however defined) and self-identity as also relevant to a more measured and full account. The context of primary care is quite different from that of secondary care. Although there are generalists who work in hospitals, we argue that this aspect and the other attributes of primary care generate special ethical considerations. One of these is how autonomy, or more fully, how respect for the principle of autonomy is considered and operationalised in community practice. In this study, we describe some theoretical aspects of autonomy and seek to apply, and challenge, these aspects in the context of clinical work in primary care. In doing so we will review the descriptors of primary care: why in essence it is different from other contexts of clinical work.

Islamic Law Regarding Claim: An Analytical Study

Islam is a complete code of life; consequently ,as it describes the particulars of worships with full detail ,similarly ,it also has a full package of principles in social ,economic, individual and collective matters and the this comprehensiveness is the distinction of Islam . So, in daily life, if one claims his right over someone, and the other denies it, Islam has a full guidance regarding this matter, which is called "Claim" in Islamic Law. In this article, full account has been given about claim, conditions for the accuracy of claim, Islamic method to prove one,s claim and also Oath in the perspective of Islamic teachings.

Self-Defence and a Phronetic Use of Violence: A Christian Response to Muslim-mob Attacks in Northern Nigeria

The sermon on the mount has often been used to support a nonviolent response to any form of injustice and violent attacks against Christians. This article argues that the sermon, understood in its original Old and New Testament contexts, does not necessarily support a wholesale prohibition of the use of violence. It also argues that the implicit ethical theory of the sermon – and the New Testament in general – is a combination of a virtue ethics and a divine command theory. On this premise, one is able to show that a measured use of violence for self-defence is a theologically tenable Christian response to unauthorized attacks. This measured use of violence for self-defence is qualified by a Christian phronesis or practical wisdom, which takes into full account both the teaching of Jesus on love of the enemy and the contextual or existential realities of Christians facing violent attacks in northern Nigeria.

Recent Progress in Flexible Graphene-Based Composite Fiber Electrodes for Supercapacitors

Graphene has shown the world its fascinating properties, including high specific surface area, high conductivity, and extraordinary mechanical properties, which enable graphene to be a competent candidate for electrode materials. However, some challenges remain in the real applications of graphene-based electrodes, such as continuous preparation of graphene fibers with highly ordered graphene sheets as well as strong interlayer interactions. The combination of graphene with other materials or functional guests hence appears as a more promising pathway via post-treatment and in situ hybridism to produce composite fibers. This article firstly provides a full account of the classification of graphene-based composite fiber electrodes, including carbon allotropy, conductive polymer, metal oxide and other two-dimensional (2D) materials. The preparation methods of graphene-based composite fibers are then discussed in detail. The context further demonstrates the performance optimization of graphene-based composite fiber electrodes, involving microstructure design and surface modification, followed by the elaboration of the application of graphene-based composite fiber electrodes in supercapacitors. Finally, we present the remaining challenges that exist to date in order to provide meaningful guidelines in the development process and prospects of graphene-based composite fiber electrodes.