Transcriptional Profiles for Glutamate Transporters Reveal Differences Between Organophosphates but Similarities with Unrelated Neurotoxicants

The developmental neurotoxicity of organophosphates involves mechanisms other than their shared property as cholinesterase inhibitors, among which are excitotoxicity and oxidative stress. We used PC12 cells as a neurodevelopmental model to compare the effects of chlorpyrifos and diazinon on the expression of genes encoding glutamate transporters. Chlorpyrifos had a greater effect in cells undergoing nerve growth factor-induced neurodifferentiation as compared to undifferentiated PC12 cells, with peak sensitivity at the initiation of differentiation, reflecting a global upregulation of all the glutamate transporter genes expressed in this cell line. In differentiating cells, chlorpyrifos had a significantly greater effect than did diazinon and concordance analysis indicated no resemblance in their expression patterns. At the same time, the smaller effects of diazinon were highly concordant with those of an organochlorine pesticide (dieldrin) and a metal (divalent nickel). We also performed similar evaluations for the cystine/glutamate exchanger, which provides protection against oxidative stress by moving cystine into the cell; again, chlorpyrifos had the greatest effect, in this case reducing expression in undifferentiated and differentiating cells. Our results point to excitotoxicity and oxidative stress as major contributors to the noncholinesterase mechanisms that distinguish the neurodevelopmental outcomes between different organophosphates while providing a means whereby apparently unrelated neurotoxicants may produce similar outcomes

Weaving ethnic identity: Discovering the threads of multilingual diversity in the fabric of group identity among Karen communities of Denver, Colorado

How do Karen immigrants use language within Colorado communities? My thesis answers this question through narrative case studies of six S’gaw Karen women. Many Karen refugees, who flee the decades-long conflict within their homeland in Myanmar (Burma), find themselves navigating life first in Thailand, and eventually in the United States as foreign-language speakers. These refugees encounter numerous linguistic and cultural barriers in their new U.S. homeland, where it is difficult to function in many domains if they do not have the opportunity to learn much English upon arrival. The six case studies are based on recorded sociolinguistic qualitative open interviews. I apply two principles from Labov (1981) in my methodology, to learn about both the personal experiences and language patterns of the Karen in their communities. I provide an emic perspective through presenting direct quotations from the women. The main languages discussed in the narratives are S’gaw Karen, Pwo Karen, English, and Burmese; the narrators maintain language use of Karen in the home and church settings, though their language is shifting to English in the work and school settings. They report that young refugees are showing shift away from the primary native Karen language of their parents. Coulmas’ (2013) utility principle and Karan’s (2011) Perceived Benefit Model provide some reasons for language shift. Children find the Karen language difficult and opt to use English instead in many cases, since they say it is easier. However, identifying as Karen ethnically for solidarity purposes is also indicated. Karen is one of the multiple identities the Karen have that accompanies language shift. Other identities for some Karen include American, immigrant, youth, and being a Burmese speaker. At times, these identities are evident through marked and unmarked code-switching. Finally, the narrators indicate that the Karen church is one of the primary institutions for preservation of Karen culture and identity

Symbolism and communication in the auditor\u27s report

https://egrove.olemiss.edu/dl_proceedings/1185/thumbnail.jp

Properties of Phase transitions of a Higher Order

The following is a thermodynamic analysis of a III order (and some aspects of a IV order) phase transition. Such a transition can occur in a superconductor if the normal state is a diamagnet. The equation for a phase boundary in an H-T (H is the magnetic field, T, the temperature) plane is derived. by considering two possible forms of the gradient energy, it is possible to construct a field theory which describes a III or a IV order transition and permits a study of thermal fluctuations and inhomogeneous order parameters.Comment: 13 pages, revtex, no figure