Morphometry of the adult human earlobe: a study of 547 subjects and clinical application

The purpose of this study was to define the factors that influence earlobe length and to establish a standard for adult earlobe length by sex and age. The study sample consisted of 547 adult subjects older than 20 years of age. A randomized, prospective design was used. Patients with malignancies, previous surgery or trauma to the earlobe, or congenital earlobe anomalies were excluded. The following variables were studied: sex; age; ethnic origin; skin complexion; height, weight, and body mass index; and piercing. Pearson's correlation, analysis of variance, t test, and multiple regression analysis were used for the statistical analysis. There were 383 women (70 percent) and 164 men (30 percent) aged 20 to 80 years. The average length of the left earlobe was 1.97 cm (SD, 0.42 cm), and that of the right earlobe, 2.01 cm (SD, 0.42 cm) (p < 0.0001). A post hoc test revealed a statistically significant difference among the three age groups (20 to 40 years, 40 to 60 years, and >60 years) in both men and women. Pendulous earlobes were significantly longer and less symmetrical than nonpendulous ones by t test. In men, nonpierced left earlobes were longer than pierced lobes; in women, there was no significant difference between pierced and nonpierced ears. Pearson's correlation tests for weight, height, and body mass index showed that only weight had a significant effect on earlobe length, and only in women. Analysis of variance for ethnic origin and skin color revealed a longer left earlobe in Ashkenazi and Sephardic Jews compared with Ethiopian, Asian, and American Jews and Arabs and a short earlobe in blacks compared with dark and fair-skinned people. On multiple regression analysis, sex and age were the only factors that contributed to earlobe length. A table of average earlobe length by age was formulated on the basis of the authors' findings. These data, together with the knowledge that earlobe length changes little in women over 40, that earlobes are not symmetrical, and that right and left nonpendulous earlobes are symmetrical in individual patients and shorter than pendulous earlobes, can assist the plastic surgeon in deciding on the proper time for loboplasty. The preferable technique is creating a nonpendulous earlobe to minimize the chances of further elongation with time.     

Gait patterns of Japanese pedestrians

Gait patterns of adult Japanese were observed while walking on a sidewalk at Fukuoka city under natural conditions on clear days during December 1987. Pedestrians were recorded by means of video recorder for eleven 1-hr observations. From the measurements of the number of steps and the time required for each subject to traverse 50 m, walking speed was calculated for 479 women and 139 men, and step length and cadence for 292 women and 117 men. The following factors were taken into account in the data analysis: footwear, accompanist, time of day, estimated age and sex. Normal values for walking speed, step length, and cadence information on present-day adult Japanese were documented. The range for the total sample was from 49 to 119 m/min in walking speed, from 51 to 91 cm in step length, and from 95 to 160 steps/min in cadence. There were no significant differences in walking speed, step length, and cadence of the women between wearing flat shoes and heeled shoes. Walking velocity and step length were greater in single walking than in group walking. As compared with the values in the daytime (10:00-15:30) velocity, step length, and cadence tended to be higher in the morning (7:30-10:00) and lower in the evening (15:30-18:00). Older people walked at a slower speed with shorter steps than younger people. For younger pedestrians no significant sex difference was observed in walking speed. Women required a higher cadence than men because of their shorter step lengths. Older men walked faster than older women.     

Smooth Pursuit Eye Movements in Children with Strabismus and in Children with Vergence Deficits

Purpose

The objective of our study was to examine horizontal smooth pursuit performance in strabismic children and in children with vergence deficits, and to compare these data with those recorded in a group of control age-matched children.

Methods

Binocular eye movements were recorded by video-oculography in ten strabismic children (mean age: 9.8±0.8) and seven children with vergence deficits (mean age: 10.8±0.6). Data were compared to that of age-matched control children (mean age: 9.8±0.8 years).

Results

Catch-up saccades amplitude in strabismic children and in children with vergence deficits were significantly higher than in control age-matched children. Moreover, in strabismic children the amplitude of catch-up saccades was significantly higher in rightward than in leftward direction. The number of catch-up saccades was also significantly higher in rightward than in leftward direction. The gain value of pursuits in rightward direction was significantly higher in the right eye than in the left one; for the right eye, the gain value was significantly higher in rightward than in leftward direction. Binocular coordination of pursuit was better in control age-matched children than in children with vergence deficits and than in strabismic children.

Conclusions

Binocular coordination of pursuit is abnormal in children with vergence deficits and worse in strabismic children. Binocular vision plays an important role in improving binocular coordination of pursuit.     

Sex differences in visual attention toward infant faces

Parental care and alloparental care are major evolutionary dimensions of the biobehavioral repertoire of many species, including human beings. Despite their importance in the course of human evolution and the likelihood that they have significantly shaped human cognition, the nature of the cognitive mechanisms underlying alloparental care is still largely unexplored. In this study, we examined whether one such cognitive mechanism is a visual attentional bias toward infant features, and if so, whether and how it is related to the sex of the adult and the adult’s self-reported interest in infants. We used eye-tracking to measure the eye movements of nulliparous undergraduates while they viewed pairs of faces consisting of one adult face (a man or woman) and one infant face (a boy or girl). Subjects then completed two questionnaires designed to measure their interest in infants. Results showed, consistent with the significance of alloparental care in human evolution, that nulliparous adults have an attentional bias toward infants. Results also showed that women’s interest in and attentional bias towards infants were stronger and more stable than men’s. These findings are consistent with the hypothesis that, due to their central role in infant care, women have evolved a greater and more stable sensitivity to infants. The results also show that eye movements can be successfully used to assess individual differences in interest in infants.     

Immaturity of the oculomotor saccade and vergence interaction in dyslexic children: evidence from a reading and visual search study

Studies comparing binocular eye movements during reading and visual search in dyslexic children are, at our knowledge, inexistent. In the present study we examined ocular motor characteristics in dyslexic children versus two groups of non dyslexic children with chronological/reading age-matched. Binocular eye movements were recorded by an infrared system (mobileEBT®, e(ye)BRAIN) in twelve dyslexic children (mean age 11 years old) and a group of chronological age-matched (N = 9) and reading age-matched (N = 10) non dyslexic children. Two visual tasks were used: text reading and visual search. Independently of the task, the ocular motor behavior in dyslexic children is similar to those reported in reading age-matched non dyslexic children: many and longer fixations as well as poor quality of binocular coordination during and after the saccades. In contrast, chronological age-matched non dyslexic children showed a small number of fixations and short duration of fixations in reading task with respect to visual search task; furthermore their saccades were well yoked in both tasks. The atypical eye movement''s patterns observed in dyslexic children suggest a deficiency in the visual attentional processing as well as an immaturity of the ocular motor saccade and vergence systems interaction.     

Comparison of two samplers for quantitatively collecting larval fishes in upper littoral habitats*

Performance of two larval fish samplers, a hand–towed net and a dropbox enclosure, was similar when tested in shallow (x water depth, 20 cm) upper littoral–zone habitats. There was no significant difference between means of larval fish density (by total catch and by species) estimated from the catch in each gear, during the day and at night. Mean length of larvae (total catch) from the tow net was significantly longer than that from the dropbox during the day, but mean length did not differ between gear at night. Mean lengths of larvae of each species between gear were not significantly different within each period. Both gears collected significantly longer larvae (total catch and by species) during the day than at night probably because of diel movements of larvae of different sizes and species.     

Correlation between serum alkaline phosphatase activity and blood glucose levels

Fasting blood glucose levels and serum alkaline phosphatase activity of age-matched Libyan diabetic men (168) and women (168) were determined. The mean levels of blood glucose of men and women were 227 +/- 6 and 237 +/- 5 mg/dl, respectively. The respective values of serum alkaline phosphatase were 179 +/- 5 and 199 +/- 6 IU/l. The mean serum phosphatase activity of women was significantly higher (p less than 0.001) than that of their male counterparts. A statistically significant positive correlation was found between serum alkaline phosphatase and blood glucose levels of these diabetic patients (r = 0.35; p less than 0.001).     

Gender Differentials in Self-Rated Health and Self-Reported Disability among Adults in India

Background

The extant literature on gender differentials in health in developed countries suggests that women outlive men at all ages, but women report poorer health than men. It is well established that Indian women live longer than men, but few studies have been conducted to understand the gender dimension in self-rated health and self-reported disability. The present study investigates gender differentials in self-rated health (SRH) and self-reported disability (SRD) among adults in India, using a nationally representative data.

Methods

Using data on 10,736 respondents aged 18 and older in the 2007 WHO Study on Global Ageing and Adult Health in India, prevalence estimates of SRH are calculated separately for men and women by socio-economic and demographic characteristics. The association of SRH with gender is tested using a multinomial logistic regression method. SRD is assessed using 20 activities of daily living (ADL). Further, gender differences in total life expectancy (TLE), disability life expectancy (DLE) and the proportion of life spent with a disability at various adult ages are measured.

Results

The relative risk of reporting poor health by women was significantly higher than men (relative risk ratio: 1.660; 95% confidence Interval (CI): 1.430–1.927) after adjusting for socio-economic and demographic characteristics. Women reported higher prevalence of severe and extreme disability than men in 14 measures out of a total20 ADL measures. Women aged less than 60 years reported two times more than men in SRD ≥ 5 ADLs. Finally, both DLE and proportion of life spent with a disability were substantially higher for women irrespective of their ages.

Conclusion

Indian women live longer but report poorer health than men. A substantial gender differential is found in self-reported disability. This makes for an urgent call to health researchers and policy makers for gender-sensitive programs.     

Reaching a Better Understanding of the Control of Bimanual Movements in Older Adults

The ability to interact skilfully with the environment is essential for independent living and therefore a critical factor for the aging population. Here we investigate the differences between young and older adults in a bimanual reaching task where the goal is to bring two objects together to the same location with a synchronous placement. Older (mean age 74) and young (mean age 20) adults were asked to pick up two spatially disparate objects, one in each hand, and bring them together to place them in one of three trays laid out in front of them from left to right. The results showed that the older adults were no more detrimentally affected than the young by asymmetric bimanual movements compared to symmetric ones, and both groups completed their movements in the same time. Nevertheless, compared to the young, the older adult group produced reaches characterised by higher peak velocities (although this effect was marginal), shorter hover times, and where the movement distance varied for each hand the scaling of the kinematic profile across the two limbs diverged from that found with younger participants. They then spent longer than the young in the final adjustment phase and during this phase they made more adjustments than the young, and as a result were more synchronous in terms of the final placement of the objects. It seems that the older adults produced reach movements that were designed to reach the vicinity of the tray quite rapidly, after which time they made discreet adjustments to their initial trajectories in order to exercise the precision necessary to place the objects in the tray. These findings are consistent with the idea that older adults have problems using online control (as they wait until they can fixate both objects before making adjustments).     

Birth weight, sexual orientation and the sex of preceding siblings.

This study's first objective was to compare the mean birth weights of homosexual and heterosexual men and women. Its second objective was to investigate whether prior male and female fetuses have different effects on the birth weight of subsequent fetuses. The subjects were 3229 adult men and women (the probands), who weighed at least 2500 g at birth, and whose mothers knew the sex of the child (or fetus) for each pregnancy prior to the proband. Information on birth weight, maternal gravidity and other demographic variables was reported on questionnaires completed by the probands' mothers. The results confirmed earlier reports that boys with older brothers weigh less at birth than boys with older sisters, but they did not confirm reports that girls with older brothers weigh less than girls with older sisters. The results did not show across-the-board differences in the mean birth weights of homosexual versus heterosexual women or homosexual versus heterosexual men. However, the homosexual males with older brothers weighed about 170 g less at birth than the heterosexual males with older brothers. It is suggested that this pattern of results may reflect a maternal immune response to Y-linked minor histocompatibility antigens (H-Y antigens). According to this hypothesis, when the maternal immune response is mild, it produces only a slightly reduced birth weight, but when it is stronger, it produces a markedly reduced birth weight as well as an increased probability of homosexuality.     

The effect of cane length and step height on muscle strength and body balance of elderly people in a stairway environment

Background

It has been reported that 75% of stairway accidents occur while descending stairs. Using a cane can help to prevent older people and those with limited mobility from falling. However, studies have shown that two-thirds of older cane users use a cane that is longer than the recommended length, which may cause unnecessary muscular loads. This study aims to assess balance and muscular load in older people descending different height steps with different cane lengths.

Methods

Nine participants (5 males and 4 females) aged over 65 years participated in this study. Cane length and stair height were independent variables. Electromyography signals were recorded from the biceps brachii of the arm that usually held the cane and from both gastrocnemius muscles. In addition, the center of pressure (CoP) was assessed as an indicator of balance in older people descending a step.

Results

Descending from higher steps resulted in the use of greater arm and leg strength at the time of first foot contact. However, cane length did not affect any of the root mean square values. In addition, the CoP Stabilometric Parameters showed that mean distance, antero-posterior mean distance, total excursions, antero-posterior total excursions, mean velocity, and antero-posterior mean velocity were significantly affected by step height, but not by cane length.

Conclusions

If cane length is within the currently suggested range, then it has little effect on the force load on the arm and legs when descending a step. Step height has a greater effect than cane length on the strategies used by older people to maintain stability.     

Gender differences in polysomnographic sleep in young healthy sleepers

Middle-aged and elderly populations exhibit gender differences in polysomnographic (PSG) sleep; however, whether young men and women also show such differences remains unclear. Thirty-one young healthy sleepers (16 men and 15 women, aged 18 to 30 yr, mean+/-SD, 20.5+/-2.4 yr) completed 3 consecutive overnight sessions in a sleep laboratory, after maintaining a stable sleep-wake cycle for 1 wk before study entry. Standard PSG sleep and self-rated sleepiness data were collected each night. Across nights, women showed better sleep quality than men: they fell asleep faster (shorter sleep onset latency) and had better sleep efficiency, with more time asleep and less time awake (all differences showed large effect sizes, d=0.98 to 1.12). By contrast, men were sleepier than women across nights. Both men and women demonstrated poorer overall sleep quality on the first night compared with the subsequent 2 nights of study. We conclude young adult healthy sleepers show robust gender differences in PSG sleep, like older populations, with better sleep quality in women than in men. These results highlight the importance of gender in sleep and circadian rhythm research studies employing young subjects and have broader implications for women's health issues relating to these topics.     

The Impact of Obesity and Arthritis on Active Life Expectancy in Older Americans

This article examines the relationship of obesity and arthritis to length of life and length of disabled life in older American men and women. Secondary data analysis is conducted on three waves of the Asset and Health Dynamics Among the Oldest Old (AHEAD) survey (n = 7,381). Using integrated Markov chains, total, active, and disabled life expectancy in Americans aged ≥70 is estimated, with and without obesity and arthritis. Results indicate that neither obesity nor arthritis is related to the length of life for older men and women, alone or in combination. However, both conditions are significantly individually associated with increased length of disabled life in older men (1.4 years attributable to obesity; 1.2 years to arthritis at age 70; P < 0.05) and women (1.7 years attributable to obesity; 2.1 years to arthritis at age 70; P < 0.05). In addition, the combination of the two is significantly related to decreased active life, with nearly 50 and 60% of remaining life for 70‐year‐old men and women lived with disability, respectively (P < 0.05). Coupled with the fact that both obesity and arthritis are growing in prevalence, these findings represent one of the few clearly negative health trends in older adults today. These results should provide incentives for health‐care professionals to make concerted efforts to address both conditions in clinical settings.     

Effects of Age and Gender on Sleep Habits and Sleep Trouble for Aged People

The healthy 455 subjects above 60 years of age were questioned on their sleep habit inventory and the morningness-eveningness questionnaire. We analyzed the effects of age and sex on sleep habits and sleep-related trouble. Bedtimes on weekdays and weekends became earlier with aging, and women went to bed significantly later than men did. The length of sleep on weekdays slightly increased with aging, and it was longer for men than for women. The number of urinations and awakenings during nocturnal sleep and the amount of daytime napping increased with aging. The score on morningness-eveningness shifted toward the morning type with aging. In comparison with men, women had significantly longer sleep latency; and a higher percentage of subjects who reported that they sleep for only a short time, have sleep trouble, have received medical treatment for their sleep trouble, and take sleep medication. From these results, we deduced that the phase of sleep shifted forward in subjects above 60 years of age, and they showed frequent interruptions during nocturnal sleep and long daytime napping. We discussed the factor of gender difference in sleep in relation to social and cultural factors, particularly the household activities of women.     

Effects of Age and Gender on Sleep Habits and Sleep Trouble for Aged People

The healthy 455 subjects above 60 years of age were questioned on their sleep habit inventory and the morningness-eveningness questionnaire. We analyzed the effects of age and sex on sleep habits and sleep-related trouble. Bedtimes on weekdays and weekends became earlier with aging, and women went to bed significantly later than men did. The length of sleep on weekdays slightly increased with aging, and it was longer for men than for women. The number of urinations and awakenings during nocturnal sleep and the amount of daytime napping increased with aging. The score on morningness-eveningness shifted toward the morning type with aging. In comparison with men, women had significantly longer sleep latency; and a higher percentage of subjects who reported that they sleep for only a short time, have sleep trouble, have received medical treatment for their sleep trouble, and take sleep medication. From these results, we deduced that the phase of sleep shifted forward in subjects above 60 years of age, and they showed frequent interruptions during nocturnal sleep and long daytime napping. We discussed the factor of gender difference in sleep in relation to social and cultural factors, particularly the household activities of women.     

A comparison of adductor pollicis fatigue in older men and women

Sex differences in fatigue resistance of the adductor pollicis (AP) muscle were studied in 24 older adults who were divided into three groups: 12 older men (69.8 +/- 4.60 years), 6 older women not on hormone replacement therapy (HRT) (70.2 +/- 4.02 years), and 6 older women on HRT (68.7 +/- 6.47 years). Fatigue in the AP muscle was induced using an intermittent (5 s contraction, 5 s rest) submaximal voluntary contraction (50% of maximal voluntary contraction (MVC)) protocol, which was continued until exhaustion (i.e., when subjects could either no longer maintain a 5-s contraction at 50% MVC or when the MVC was deemed to be lower than the target force). There was no effect of HRT on MVC or time to fatigue (TTF); therefore, the older women were pooled as one subject group. At baseline, men were stronger than women for MVC (75.9 +/- 18.8 N in men vs. 56.8 +/- 10.0 N in women; P < 0.05) and evoked twitch force (7.3 +/- 1.7 N in men vs. 5.2 +/- 0.8 N in women; P < 0.05). There was no difference in TTF between men and women (14.77 +/- 7.06 min in men vs. 11.53 +/- 4.91 min in women; P > 0.20), nor was there a significant relationship between baseline muscle force and TTF (r = 0.14). There was also no difference in the pattern of fatigue and recovery between the men and women. These results suggest that there is no difference in endurance or fatigue characteristics of the AP muscle in men and women over the age of 65 years, and that baseline muscle force does not predict fatigue resistance in this muscle.     

Hemodynamics and brain blood flow during posture change in younger women and postmenopausal women compared with age-matched men

Increased incidence of orthostatic hypotension and presyncopal symptoms in young women could be related to hormonal factors that might be isolated by comparing cardiovascular and cerebrovascular responses to postural change in young and older men and women. Seven young women, 11 young men, 10 older women (>1 yr postmenopausal, no hormone therapy), and 9 older men participated in a supine-to-sit-to-stand test while measuring systemic hemodynamics, end-tidal Pco(2), and blood flow velocity of the middle cerebral artery (MCA). Women had a greater reduction in stroke volume index compared with age-matched men (change from supine to standing: young women: -22.9 ± 1.6 ml/m(2); young men: -14.4 ± 2.4 ml/m(2); older women: -17.4 ± 3.3 ml/m(2); older men: -13.8 ± 2.2 ml/m(2)). This was accompanied by offsetting changes in heart rate, particularly in young women, resulting in no age or sex differences in cardiac output index. Mean arterial pressure (MAP) was higher in older subjects and increased with movement to upright postures. Younger men and women had higher forearm vascular resistance that increased progressively in the upright posture compared with older men and women. There was no difference between sexes or ages in total peripheral resistance index. Women had higher MCA velocity, but both sexes had reduced MCA velocity while upright, which was a function of reduced blood pressure at the MCA and a significant reduction in end-tidal Pco(2). The reductions in stroke volume index suggested impaired venous return in women, but augmented responses of heart rate and forearm vascular resistance protected MAP in younger women. Overall, these results showed significant sex and age-related differences, but compensatory mechanisms preserved MAP and MCA velocity in young women.     

Androgens and eye movements in women and men during a test of mental rotation ability

Eye movements were monitored in 16 women and 20 men during completion of a standard diagram-based test of mental rotation ability to provide measures of cognitive function not requiring conscious, decisional processes. Overall, women and men allocated visual attention during task performance in very similar, systematic ways. However, consistent with previous suggestions that sex differences in attentional processes during completion of the mental rotation task may exist, eye movements in men compared to women indicated greater discrimination and longer processing of correct alternatives during task performance. Other findings suggested that androgens may enhance cognitive processes that are recruited differentially by women and men as a function of the task. Specifically, smaller (i.e., more masculine) digit ratios were associated with men's shorter fixations on distracters, suggesting that perinatal androgen action may influence brain systems that facilitate the identification of relevant task stimuli. In women, higher circulating testosterone levels appeared to contribute to more general processes engaged during task performance, for example higher levels of visual persistence. It is possible that variability in the relative contribution of such hormone sensitive cognitive processes to accuracy scores as a function of different sample characteristics or assessment methods may partially account for the inconsistent findings of previous research on hormonal factors in mental rotation ability.     

The effects of lowered temperature on spontaneous eye movements in a teleost fish

A new opto-electronic method has been used to measure spontaneous eye movements in a lightly restrained unanaesthetized marine teleost fish (Parore). The normal scanning pattern of eye movement is similar to that previously described in goldfish. The effects of cooling on eye movements were investigated by 2 degrees C step changes down from ambient temperature (13-14 degrees C). Lowered temperature altered the scanning pattern, decreased saccade velocity, increased mean saccade amplitude and impaired the ability of the fish to hold the eye stationary between saccades. All eye movements stopped at temperatures around 6 degrees C, but could be restored by subsequent warming.     

Pulmonary function in young and older athletes and untrained men

This study compared the lung volumes and pulmonary functions of older endurance-trained athletes with those of healthy sedentary age-matched controls, young athletes, and young untrained men to determine whether training affects the age-associated changes in these variables. Despite large differences in maximal 02 consumption (VO2max), the older athletes and their sedentary peers had similar values for all pulmonary variables when expressed as absolute values. However, because the older athletes were shorter than the older sedentary men, their vital capacity, total lung capacity (TLC), and forced expiratory volume in 1 s were significantly larger than those of the older sedentary men when normalized for age and height; the average values for maximal voluntary ventilation and residual volume (RV) were also larger in the older athletes when normalized for age and height, but the differences were not significant. The young trained and untrained men did not differ in any of these measures. TLC was the only pulmonary variable that was the same in the young and older men; RV and the RV-to-TLC ratio were larger, whereas all other pulmonary function and volume measures were lower in the older men compared with the younger men. The older athletes were the only group whose lung volumes and pulmonary function measures were all, except for RV, substantially greater than expected based on their age and height. Thus prolonged strenuous endurance training in these older highly trained endurance athletes appears to have altered the decline in pulmonary function and volumes associated with aging.