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Biomedical subjects

M D Wang

Publications and source records attributed to M D Wang.

46 records · Page 3Linked to original sources
PubMed1984

Studies on derivatives of 2,3-dihydro-4H-1,3,2-benzoxazaphosphorine. Synthesis and structure analysis of 2,3-disubstituted-2,3-dihydro-4H-1,3,2-benzoxazaphosphorin-4-one -(thio ne)-2-sulfide(oxide).

A series of novel organocyclophosphorus compounds including twenty-three 2,3-disubstituted-2,3-dihydro-4H-1,3,2-benzoxazaphosphorin-4-one-2 -sulfide (compounds I) and three 2,3-disubstituted-2,3-dihydro-4H-1,3,2-benzoxazaphosphorin-4-th ion e-2-oxide (compounds II) have been synthesized. Their structures were determined by IR, UV, 1HNMR, X-ray diffraction and elemental analysis. Each of compounds I showed a strong absorption between 1290-1319 cm-1 in the IR spectrum. Comprehensive studies of the spectral data and experimental results indicated that this strong characteristic absorption is different from that of the P = O linkage and thus could be considered as a result of the stretching vibration of (unsaturated C)-N single bond. In the course of synthesis of the compounds, an abnormal product (Formula: see text) is frequently formed as an isomer of the expected product I (Formula: see text). However, by suitable choice of condensation conditions, either of the isomers could be made predominantly in yield and be readily isolated from the other by recrystallizing for several times from appropriate solvent. Data for the melting point, IR, UV and 1HNMR spectra of three pairs of the isomers are given, and primary analyses of the spectra are made as well.

Fungicides, Industrial↗
PubMed1978

A comparison of the effects of filtering and sensorineural hearing loss on patients of consonant confusions.

It has been found that listeners with sensorineural hearing loss who show similar patterns of consonant confusions also tend to have similar audiometric profiles. The present study determined whether normal listeners, presented with filtered speech, would produce consonant confusions similar to those previously reported for the hearing-impaired listener. Consonant confusion matrices were obtained from eight normal-hearing subjects for four sets of CV and VC nonsense syllables presented under six high-pass and six-low pass filtering conditions. Patterns of consonant confusion for each condition were described using phonological features in sequential information analysis. Severe low-pass filtering produced consonant confusions comparable to those of listeners with high-frequency hearing loss. Severe high-pass filtering gave a result comparable to that of patients with flat or rising audiograms. And, mild filtering resulted in confusion patterns comparable to those of listeners with essentially normal hearing. An explanation in terms of the spectrum, the level of speech, and the configuration of this individual listener's audiogram is given.

Audiometry↗
PubMed1976

Consonant confusions in patients with sensorineural hearing loss.

Consonant confusion matrices were obtained from 22 outpatient listeners with sensorineural hearing loss for four sets of CV and VC nonsense syllables, presented monaurally at SRT + 40 DB. Testing was typically conducted for six hours on each of two separate days. Overall performance and patterns of confusions were stable over time. Analysis of the matrices in terms of phonological features indicated that the patterns of consonant confusions varied both with degree and configuration of the subject's loss. Scaling of intersubject similarity using a pairwise multidimensional scaling analysis resulted in consistent classification of subjects according to audiometric configuration into three groups-essentially normal hearing, flat or rising audiograms, and high-frequency hearing losses.

Adult↗