METHODS: Data were obtained from large samples of students enrolled at universities in Malaysia and the US, including self-reported information on handedness, sexual orientation, and five somatic markers of prenatal androgen exposure (2D:4D, height, strength, muscularity, and athletic ability). Factor analysis of these somatic markers yielded two factors: a muscular coordination and a bone growth factor.
RESULTS: In women, but not in men, ambidextrousness was more prevalent among those with homosexual tendencies. Modest and often complex associations were found between the androgen factors and handedness. Clear links between the androgen factors and sexual orientation were found, especially for muscular coordination. For males and females, intermediate sex-typical androgen exposure was associated with heterosexual preferences.
CONCLUSIONS: Ambidextrousness appears to be somewhat more common among females with homosexual tendencies, but left-handedness is nearly as strongly associated with heterosexual preferences, particularly in males, as is right-handedness. Factors indicative of prenatal androgen exposure are associated with sexual orientation in theoretically predictable ways, especially for muscular coordination, but associations between prenatal androgens and handedness are complex.
Method: Participants of this cross-sectional study included 99 full-term neonates (165 ears) with mean chronological age of 46.7 hrs (SD = 26.3 hrs). Of the 99 neonates, 58 were Malay, 28 were Indian, and 13 were Chinese. The neonates who passed high-frequency (1 kHz) tympanometry, acoustic stapedial reflex, and distortion product otoacoustic emission screening tests were assessed using a pressurized WBA test (wideband tympanometry). To reduce the number of measurement points, the WBA responses were averaged to 16 one-third octave frequency bands from 0.25 to 8 kHz. A mixed-model analysis of variance was applied to the data to investigate the effects of frequency, ear, gender, and ethnicity on WBA. The analysis of variance was also used to compare between WBA measured at TPP and 0 daPa. An interclass correlation coefficient test was applied at each of the 16 frequency bands to measure the test-retest reliability of WBA at TPP and 0 daPa.
Results: Both WBA measurements at TPP and 0 daPa exhibited a multipeaked pattern with 2 maxima at 1.25-1.6 kHz and 6.3 kHz and 2 minima at 0.5 and 4 kHz. The mean WBA measured at TPP was significantly higher than that measured at 0 daPa at 0.25, 0.4, 0.5, 1.25, and 1.6 kHz only. A normative data set was developed for absorbance at TPP and at 0 daPa. There was no significant effect of ethnicity, gender, and ear on both measurements of WBA. The test-retest reliability of WBA at TPP and 0 daPa was high with the interclass correlation coefficient ranging from 0.77 to 0.97 across the frequencies.
Conclusions: Normative data of WBA measured at TPP and 0 daPa for neonates were provided in the present study. Although WBA at TPP was slightly higher than the WBA measured at 0 daPa at some frequencies below 2 kHz, the WBA patterns of the 2 measurements were nearly identical. Moreover, the test-retest reliability of both WBA measurements was high.
AIM OF THE WORK: Is to study the pattern of lip print in Egyptian and Malaysian populations and its relation to sex and populations difference. Also, to develop equations for sex and populations detection using lip print pattern by different populations (Egyptian and Malaysian).
SUBJECTS AND METHODS: The sample comprised of 120 adults volunteers divided into two ethnic groups; sixty adult Egyptians (30 males and 30 females) and sixty adult Malaysians (30 males and 30 females). The lip prints were collected on a white paper. Each lip print was divided into four compartments and were classified and scored according to Suzuki and Tsuchihashi classification. Data were statistically analyzed.
RESULTS: The results showed that type III lip print pattern (intersected grooves) was the predominant type in both the Egyptian and Malaysian populations. Type II and III were the most frequent in Egyptian males (28.3% each), while in Egyptian females type III pattern was predominant (46.7%). As regards Malaysian males, type III lip print pattern was the predominant one (41.7%), while type II lip print pattern was predominant (30.8%) in Malaysian females. Statistical analysis of different quadrants showed significant differences between males and females in the Egyptian population in the third and fourth quadrants. On the other hand, significant differences were detected only in the second quadrant between Malaysian males and females. Also, a statistically significant difference was present in the second quadrant between Egyptian and Malaysian males. Using the regression analysis, four regression equations were obtained.