Many researchers have reported that the magnitude of decrease in cortical choline acetyltransferase (ChAT) following excitotoxic lesions of the nucleus basalis magnocellularis (nbm) is unrelated to the degree of cognitive impairment. Recently, an explanation has been offered for this lack of correlation: different excitotoxins, when injected into the nbm, differentially affected cholinergic pro...

Changes of choline acetyltransferase (ChAT) activity in the hippocampus and the basal ganglia were studied in rats treated i.p. with L-carnitine (CRT) and 7-methoxytacrine (7-MEOTA) (i.m.) separately or 3-days treated with L-carnitine and then with one administration of 7-MEOTA. Both compounds increased ChAT activity when administered separately. 3-day treatment of CRT followed by administratio...

This paper presents concepts, content, status, applications and challenges of chat as used in the military context of secure net-centric command and control. It describes the importance of chat as it contributes to situation assessment and the common operating picture, which presents current collective knowledge of the battle space. The paper discusses future chat capabilities and outlines the ...

BACKGROUND After alcohol and tobacco, cannabis is the most widely used psychoactive substance in many countries worldwide. Although approximately one in ten users develops serious problems of dependency, only a minority attend outpatient addiction counseling centers. A Web-based intervention could potentially reach those users who hesitate to approach such treatment centers. OBJECTIVE To test...

Quantitative in situ hybridization techniques were used to compare relative cellular levels of choline acetyltransferase (ChAT) mRNA in different regions of the female rat basal forebrain at different stages of the estrous cycle and at different time points after the administration of physiological levels of estrogen and progesterone. Significant fluctuations in relative levels of ChAT mRNA wer...

Bilateral or group text chatting over the Internet has become a favoured pastime for many people across the world. Yet it would seem that, in general, text chat is a severely impoverished mode of on-line communication compared to, e.g., fully situated human-human spoken conversation, video conferencing, or even speaking over the telephone. This paper explores what happens when on-line multi-spe...

The inspiratory drive to hypoglossal (XII) motoneurons originates in the caudal medullary intermediate reticular (IRt) region. This drive is mainly glutamatergic, but little is known about the neurochemical features of IRt XII premotor neurons. Prompted by the evidence that XII motoneuronal activity is controlled by both muscarinic (M) and nicotinic cholinergic inputs and that the IRt region co...

Several recent studies indicate that activity of cholinergic enzymes in the cortex of people with mild cognitive impairment (MCI) and early Alzheimer's disease (AD) are preserved. We correlated levels of hippocampal choline acetyltransferase (ChAT) activity with the extent of AD lesions in subjects from the Religious Order Study, including cases with no cognitive impairment (NCI), MCI, and with...

The idea for this paper came from a debate at the 1998 ISCRAT conference in Denmark on cultural-historical activity theory (CHAT). A leading activist in the movement to bring CHAT into systems design, Bonnie Nardi, asked the question; would design not bene"t more from training better ethnographers than from burdening them with such a complex set of theoretical concepts and debates as CHAT? This...

Although instant messaging is a very popular tool for collaboration and it has been used for a wide variety of CSCL tasks, there are only a few applications for assisting the tutors in evaluating the conversations of the students. Due to the difficulty of this task, chat is seldom used in a formal education context. In order to tackle this problem, several applications were developed which assi...