PubMed HealthSearch

Biomedical subjects

C Snow

Publications and source records attributed to C Snow.

7 recordsLinked to original sources

The wheat and the chaff: or four confusions regarding CHILDES.

Edwards (1992) presents a set of examples from the Child Language Data Exchange System (CHILDES) as prototypes of bad transcription practice. Her discussion is based upon four basic confusions. First, Edwards confuses old and discarded versions of CHAT with current CHAT. Second, she confuses the relation between CHAT standards with the implementation of these standards during the process of reformatting older corpora. Third, she confuses transcription for automatic analysis with transcription for documentation. Fourth, she confuses the CHAT guidelines with the larger CHILDES system. We argue that these confusions have misled Edwards into developing an overly rigid set of principles for data analysis which, if followed literally, could choke off progress in the analysis of spontaneous language samples.

Archives

The Child Language Data Exchange System: an update.

In a previous issue of this Journal, MacWhinney & Snow (1985) laid out the basic sketch for an international system for exchanging and analysing child language transcript data. This system--the Child Language Data Exchange System (CHILDES)--has developed three major tools for child language research: (1) the CHILDES database of transcripts, (2) the CHAT system for transcribing and coding data, and (3) the CLAN programs for analysing CHAT files. Here we sketch out the current shape of these three major tools and the organizational form of the CHILDES system. A forthcoming book (MacWhinney, in press) documents these tools in detail.

Child

Differences of T-cell activation by the anti-CD3 antibodies Leu4 and BMA030.

Two anti-CD3 antibodies and their Fab/F(ab')2 fragments were compared with regard to their requirement for secondary signals and generations of intracellular messengers. The anti-CD3 antibody BMA030 was found to require monocyte contact to elicit T-cell mitogenesis. Cross-linking by plastic-bound goat anti-mouse antibodies (panning) failed to activate T cells, even in the presence of recombinant IL-1 or IL-2. In contrast, crosslinking of the anti-CD3 antibody Leu4 or Leu4 fragments was mitogenic in monocyte-free cultures. Measurements of intracellular Ca2+ ([Ca2+]i) and generation of inositol phosphates revealed that binding (+/- panning) of BMA030, Leu4, and their F(ab')2 fragments generated similar amounts of intracellular messengers and thus failed to explain the different responsiveness to passive crosslinking. Since the generation of these messengers was not necessarily followed by proliferation but was always observed when mitogenesis occurred, we conclude that the elevation of [Ca2+]i and the production of inositol phosphates are required but not sufficient to trigger mitogenesis.

Adult