scholarly journals The Spectral Sensitivity of the Neurons Mediating Black and White

2019 ◽  
Author(s):  
Sara S. Patterson ◽  
Maureen Neitz ◽  
Jay Neitz
Keyword(s):  
Spectral Sensitivity ◽  
Ganglion Cells ◽  
Neural Substrates ◽  
Spectral Tuning ◽  
Cone Photoreceptors ◽  
Black And White

Our percepts of black and white are not equally strong for all monochromatic lights across the spectrum, but instead have a spectral tuning defined by they ways in which their neural substrates process the outputs of three univariant cone photoreceptors. The neurons mediating black and white and how they combine the cone outputs remain controversial but growing evidence indicates cone-opponent midget ganglion cells are involved. The paradoxical implications of having “chromatic” neurons mediate what is traditionally assumed to be a role of “achromatic” neurons remain unresolved. Here, we investigate whether midget ganglion cells can account for the variation in perceived saturation with wavelength.

Emerging Challenges and Opportunities of Mobile Commerce in India: A Study on Societal Perspective

2016 ◽  
Vol 6 (1) ◽  
Author(s):  
Utkarsh Kumar ◽  
Anil Kumar Gope ◽  
Shweta Singh
Keyword(s):  
Growth Rate ◽  
Societal Perspective ◽  
Mobile Applications ◽  
Mobile Application ◽  
Mobile Commerce ◽  
Mobile Banking ◽  
Black And White ◽  
The People ◽  
Challenges And Opportunities

In India, the position of mobile banking was in saga and this time, it is in pic position. The speedof reaching the people is going high and high. This is time of wireless world and sense of prestige; no doubt the mobile commerce is contributing to enhance the beauty of life and playing the role of metaphor and has become the part and parcel of our life. This growth has changed people to do business in mobile commerce (М- Commerce). Peoples are transferring to M-Commerce to attain good and fast transaction into market and saving their precious time. M-Commerce has become distinguished in Indian people, quickly during last few years. Due to large number of mobile application, growth rate in mobile penetration in India is increasing with the rapid speed. The mobile users has shifted to use the android phone from simple and black and white phone and taking the service of internet, the role of telecom companies is also important in the being popular of mobile commerce. Although many people have started E-Commerce but still a separate part of the society feel uncomfortable and hesitate to use M-Commerce because of security problems, payment issues and complexity of mobile applications. This paper identifies facts about the feasibility of MCommercein India today its growth and the Strength and opportunity, weakness and threats lying ahead.

The Constitutional Court of South Africa: Thoughts on its 25-Year-Long Legacy of Judicial Activism

2021 ◽  
Vol 56 (1) ◽  
pp. 18-33
Author(s):  
Lucky Mathebe
Keyword(s):  
South Africa ◽  
Constitutional Court ◽  
Transformative Change ◽  
Democratic Accountability ◽  
Constitutional Democracy ◽  
The Public ◽  
Crime And Punishment ◽  
Black And White ◽  
Marginalised Groups

After almost 25 years of what could justifiably be called transformative change in South Africa, a truism is that the country’s new legal order, established by the Constitution in 1993 and 1996, provides the critical foundation of peace and security upon which its freedom has been built. The Constitutional Court was one of the most important of the new democratic institutions in the shaping of the country’s position as a constitutional democracy, upholding the values for which millions of people, black and white, had fought. This article is a brief reflection on the role of the Court in establishing the meaning of this democracy and giving it effect. The main goal of the article is to understand how the Court’s new jurisprudence works in particular contexts, how its work is related to crime and punishment, and what it means for the rights of marginalised groups in society. Using the examples of the Court’s decision in Makwanyane on the death penalty, and the Court’s decision on the findings of the Public Protector’s report on Nkandla, the article finds that the Court’s new jurisprudence takes quite a different view of legal developments in South Africa, insofar as the jurisprudence entrusts broad discretion to the Court and emphasises the need for sustained leadership of the Court to advance the battle for fundamental human rights, the rule of law, and democratic accountability.

scholarly journals A Scientometric Approach to Review the Role of the Medial Preoptic Area (MPOA) in Parental Behavior

2021 ◽  
Vol 11 (3) ◽  
pp. 393
Author(s):  
Alessandro Carollo ◽  
Jan Paolo Macapinlac Balagtas ◽  
Michelle Jin-Yee Neoh ◽  
Gianluca Esposito
Keyword(s):  
Preoptic Area ◽  
Parental Behavior ◽  
Neural Substrates ◽  
Medial Preoptic Area ◽  
Brain Network ◽  
Scientometric Analysis ◽  
Parental Behaviour ◽  
Scientific Papers ◽  
The Relationship

Research investigating the neural substrates underpinning parental behaviour has recently gained momentum. Particularly, the hypothalamic medial preoptic area (MPOA) has been identified as a crucial region for parenting. The current study conducted a scientometric analysis of publications from 1 January 1972 to 19 January 2021 using CiteSpace software to determine trends in the scientific literature exploring the relationship between MPOA and parental behaviour. In total, 677 scientific papers were analysed, producing a network of 1509 nodes and 5498 links. Four major clusters were identified: “C-Fos Expression”, “Lactating Rat”, “Medial Preoptic Area Interaction” and “Parental Behavior”. Their content suggests an initial trend in which the properties of the MPOA in response to parental behavior were studied, followed by a growing attention towards the presence of a brain network, including the reward circuits, regulating such behavior. Furthermore, while attention was initially directed uniquely to maternal behavior, it has recently been extended to the understanding of paternal behaviors as well. Finally, although the majority of the studies were conducted on rodents, recent publications broaden the implications of previous documents to human parental behavior, giving insight into the mechanisms underlying postpartum depression. Potential directions in future works were also discussed.

scholarly journals Endothelin 1-induced retinal ganglion cell death is largely mediated by JUN activation

2020 ◽  
Vol 11 (9) ◽  
Author(s):  
Olivia J. Marola ◽  
Stephanie B. Syc-Mazurek ◽  
Gareth R. Howell ◽  
Richard T. Libby
Keyword(s):  
Transcription Factor ◽  
Molecular Mechanisms ◽  
Ganglion Cells ◽  
Retinal Vessel ◽  
Vessel Diameter ◽  
Retinal Ganglion ◽  
Retinal Ganglion Cell Death ◽  
Ganglion Cell Death

Abstract Glaucoma is a neurodegenerative disease characterized by loss of retinal ganglion cells (RGCs), the output neurons of the retina. Multiple lines of evidence show the endothelin (EDN, also known as ET) system is important in glaucomatous neurodegeneration. To date, the molecular mechanisms within RGCs driving EDN-induced RGC death have not been clarified. The pro-apoptotic transcription factor JUN (the canonical target of JNK signaling) and the endoplasmic reticulum stress effector and transcription factor DNA damage inducible transcript 3 (DDIT3, also known as CHOP) have been shown to act downstream of EDN receptors. Previous studies demonstrated that JUN and DDIT3 were important regulators of RGC death after glaucoma-relevant injures. Here, we characterized EDN insult in vivo and investigated the role of JUN and DDIT3 in EDN-induced RGC death. To accomplish this, EDN1 ligand was intravitreally injected into the eyes of wildtype, Six3-cre+Junfl/fl (Jun−/−), Ddit3 null (Ddit3−/−), and Ddit3−/−Jun−/− mice. Intravitreal EDN1 was sufficient to drive RGC death in vivo. EDN1 insult caused JUN activation in RGCs, and deletion of Jun from the neural retina attenuated RGC death after EDN insult. However, deletion of Ddit3 did not confer significant protection to RGCs after EDN1 insult. These results indicate that EDN caused RGC death via a JUN-dependent mechanism. In addition, EDN signaling is known to elicit potent vasoconstriction. JUN signaling was shown to drive neuronal death after ischemic insult. Therefore, the effects of intravitreal EDN1 on retinal vessel diameter and hypoxia were explored. Intravitreal EDN1 caused transient retinal vasoconstriction and regions of RGC and Müller glia hypoxia. Thus, it remains a possibility that EDN elicits a hypoxic insult to RGCs, causing apoptosis via JNK-JUN signaling. The importance of EDN-induced vasoconstriction and hypoxia in causing RGC death after EDN insult and in models of glaucoma requires further investigation.

Expression of the BDNF gene in the developing visual system of the chick

Development ◽  
1994 ◽  
Vol 120 (6) ◽  
pp. 1643-1649 ◽  
Author(s):  
K.H. Herzog ◽  
K. Bailey ◽  
Y.A. Barde
Keyword(s):  
Visual System ◽  
Ganglion Cells ◽  
Mrna Levels ◽  
Retinal Ganglion ◽  
Bdnf Gene ◽  
Bdnf Mrna ◽  
Optic Stalk ◽  
Copy Numbers ◽  
Activity Dependent

Using a sensitive and quantitative method, the mRNA levels of brain-derived neurotrophic factor (BDNF) were determined during the development of the chick visual system. Low copy numbers were detected, and BDNF was found to be expressed in the optic tectum already 2 days before the arrival of the first retinal ganglion cell axons, suggesting an early role of BDNF in tectal development. After the beginning of tectal innervation, BDNF mRNA levels markedly increased, and optic stalk transection at day 4 (which prevents subsequent tectal innervation) was found to reduce the contralateral tectal levels of BDNF mRNA. Comparable reductions were obtained after injection of tetrodotoxin into one eye, indicating that, already during the earliest stages of target encounter in the CNS, the degree of BDNF gene expression is influenced by activity-dependent mechanisms. BDNF mRNA was also detected in the retina itself and at levels comparable to those found in the tectum. Together with previous findings indicating that BDNF prevents the death of cultured chick retinal ganglion cells, these results support the idea that the tightly controlled expression of the BDNF gene might be important in the co-ordinated development of the visual system.

The Impact of Childhood Experience on Amygdala Response to Perceptually Familiar Black and White Faces

2014 ◽  
Vol 26 (9) ◽  
pp. 1992-2004 ◽  
Author(s):  
Jasmin Cloutier ◽  
Tianyi Li ◽  
Joshua Correll
Keyword(s):  
Neural Substrates ◽  
Relative Reduction ◽  
Childhood Experience ◽  
Childhood Exposure ◽  
Interracial Contact ◽  
Black And White ◽  
Race Perception ◽  
Amygdala Response ◽  
The Impact ◽  
Black Faces

Given the well-documented involvement of the amygdala in race perception, the current study aimed to investigate how interracial contact during childhood shapes amygdala response to racial outgroup members in adulthood. Of particular interest was the impact of childhood experience on amygdala response to familiar, compared with novel, Black faces. Controlling for a number of well-established individual difference measures related to interracial attitudes, the results reveal that perceivers with greater childhood exposure to racial outgroup members display greater relative reduction in amygdala response to familiar Black faces. The implications of such findings are discussed in the context of previous investigations into the neural substrates of race perception and in consideration of potential mechanisms by which childhood experience may shape race perception.

Modeling the Inflation Response of C57BL/6 Mouse Sclera

2011 ◽  
Author(s):  
Kristin M. Myers ◽  
Thao D. Nguyen
Keyword(s):  
Material Properties ◽  
Soft Tissues ◽  
Ganglion Cells ◽  
The United States ◽  
Small Rodent ◽  
Tissue Samples ◽  
Tissue Microstructure ◽  
Material Parameters ◽  
Meaningful Material

Small rodent models have become increasingly useful to investigate how the mechanical properties of soft tissues may influence disease development. These animal models allow access to aged, diseased, or genetically-altered tissue samples, and through comparisons with wild-type or normal tissue it can be explored how each of these variables influence tissue function. The challenges to deriving meaningful material parameters for these small tissue samples include designing physiologically-relevant mechanical testing protocols and interpreting the experimental load-displacement data in an appropriate constitutive framework to quantify material parameters. This study was motivated by determining the possible role of scleral material properties in the development of glaucomatous damage to the retinal ganglion cells (RGC). Glaucoma is one of the leading causes of blindness in the United States and in the world with an estimate of 60 million people affected by this year [1]. Through exploring mouse models, the overall goal of our work is to determine the role of scleral material properties and scleral tissue microstructure in the pathogenesis of glaucoma.

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