A Tribute to Hon. George Bundy Smith -- Leadership

A tribute to George Bundy Smith, highlighting his commitment to social justice

Sources of extracellular glutamate in developing white matter

Neurotransmitters mediate synaptic communication between neurons and are therefore fundamental to such essential human characteristics as learning, memory, cognition and persona. Recent work indicates that neurotransmitters and their receptors are also used for communication between non-synaptic elements of the nervous system and may be involved in glial-glial, glia-axon and glial-neuronal information transfer and processing. We have recently found evidence that glial cells in developing white matter, which contains no synapses or neuronal somata, express a wide variety of neurotransmitter receptors, including the NMDA-type glutamate receptor that had long thought to be exclusively neuronal. At the point when white matter is laying down myelin and glial cells are forming their long-term morphological arrangement with axons, NMDA receptors mediate post-synaptic-potential input onto glia and may be crucially involved in stabilizing glial-axonal cyto-architecture. There is also strong evidence that glutamate receptors on glial cell membranes greatly heighten the cells susceptibility to injury, a phenomenon that may explain the selective damage of developing white matter found in common human birth disorders such as cerebral palsy. There are many potential sources of extracellular glutamate in ischemic white matter including axons, oligodendrocytes, reverse glutamate transport, loss of astrocyte processes and astrocyte swelling. These potential pathways for glutamate release are described here.peer-reviewe

The Structure of Optimal and Near Optimal Target Sets in Consensus Models

We consider the problem of identifying a subset of nodes in a network that will enable the fastest spread of information in a decentralized environment.In a model of communication based on a random walk on an undirected graph, the optimal set over all sets of the same or smaller cardinality minimizes the sum of the mean first arrival times to the set by walkers starting at nodes outside the set. The problem originates from the study of the spread of information or consensus in a network and was introduced in this form by V.Borkar et al. in 2010. More generally, the work of A. Clark et al. in 2012 showed that estimating the fastest rate of convergence to consensus of so-called leader follower systems leads to a consideration of the same optimization problem. The set function $F$ to be minimized is supermodular and therefore the greedy algorithm is commonly used to construct optimal sets or their approximations. In this paper, the problem is reformulated so that the search for solutions is restricted to optimal and near optimal subsets of the graph. We prove sufficient conditions for the existence of a greedoid structure that contains feasible optimal and near optimal sets. It is therefore possible we conjecture, to search for optimal or near optimal sets by local moves in a stepwise manner to obtain near optimal sets that are better approximations than the factor $(1-1/e)$ degree of optimality guaranteed by the use of the greedy algorithm. A simple example illustrates aspects of the method.Comment: arXiv admin note: substantial text overlap with arXiv:1401.696

The Intention Determinants Of Recycling Behavior Among Malaysians

Penjanaan sisa-sisa buangan di Bumi semakin meningkat akibat pertumbuhan pesat penduduk, kekayaan kewangan pengguna bertambah baik dan pembangunan perindustrian berkembang pesat. Waste generation in the Earth is increasing as consequences of the rapid growth in population, consumers’ financial wealth improved as well as the industrial development

Fairness in Flowers: Campaign Toolkit

This document is part of a digital collection provided by the Martin P. Catherwood Library, ILR School, Cornell University, pertaining to the effects of globalization on the workplace worldwide. Special emphasis is placed on labor rights, working conditions, labor market changes, and union organizing.ILRF_Flowers_ToolKit_2008.pdf: 511 downloads, before Oct. 1, 2020