Assessment of Midline Lingual Point-Pressure Somatosensation Using Von Frey Hair Monofilaments.

Detection and discrimination threshold estimates for oral point pressure are assessed using Von Frey Hair monofilaments. Consistent with previously published protocols, threshold estimates are determined using a two-interval forced choice (2-IFC) paradigm with a three down/one up approach. Detection threshold estimates determine the mean force in which a participant can identify the presence of pressure. During the detection threshold procedure, the participant is instructed to choose which of two sequentially presented observation intervals contained the tactile test stimulus. If the participant performs three correct detections in a row (i.e., 3 'hits'), the researcher decreases the stimulus to the next lower target force level. With one incorrect detection (a 'miss'), the researcher increases the force delivered to the next higher level. This threshold estimation approach is known as a 3-down/1-up adaptive staircase. Reponses are recorded on a paper ballot, and a participant's estimated threshold is defined as the geometric mean of five reversals. During the discrimination threshold procedure, the participant is asked to make a choice between two serially presented stimuli as to which is the "harder" or "stronger" pressure. The same scoring of 'hits', 'misses', and stopping points are used. Detection and discrimination testing for oral point pressure at tongue midline takes approximately 20 min to complete. Using these commercially-available clinical tools, individual touch sensation profiles for the midline tongue can be achieved in a relatively time and cost effective means.

EEMCO Guidance for the in vivo Assessment of Biomechanical Properties of the Human Skin and Its Annexes: Revisiting Instrumentation and Test Modes.

Biomechanics of the skin is an important subject in skin research. It has been studied for many decades involving various technologies and methods to characterize and quantify mechanical properties of the skin under different in vivo conditions. The present EEMCO paper reviews the current rel-evant information, providing practical orientation to researchers dedicated to in vivo assessment of biomechanics of skin and its annexes. We discuss the available non-invasive instruments, including their principles and variables. A correspondence between the descriptors nomenclature proposed by Agache and the designation for the suction-based standard instruments is proposed. The addressed properties include skin softness/stiffness, firmness, elasticity, elastic and viscoelastic properties, extensibility, resilience, anisotropy, acoustical shock wave hardness, friction (in relation to topographic properties), thickness, fiber/stress mechanics (bending, cyclic, tensile, fatigue, or torsion), and hardness. We provide the relation of these properties to biomechanical descriptors and in some cases to SI units. Practical guidance for the proper use of these instruments, limitations, and possible interpretations are provided, while discussing the meaning of descriptive or "phenomenological" variables. For studies intended to quantify the effect of an intervention with regard to mechanical properties, we recommend a minimum of 30-40 participants, based on normal distribution of the data sets. Some important limitations are recognized, including the lack of standardization of procedures and calibration of instruments, which compromises the relevance and real nature of the descriptors/parameters obtained with these devices. The present work highlights an approach to a better practice and a science-supported biomechanical assessment of human skin, hair, and nails.

Genetic and environmental influences on pubertal hormones in human hair across development.

Puberty is a complex biopsychosocial process that can affect an array of psychiatric and medical disorders emerging in adolescence. Although the pubertal process is driven by neuroendocrine changes, few quantitative genetic studies have directly measured puberty-relevant hormones. Hair samples can now be assayed for accumulation of hormones over several months. In contrast to more conventional salivary measures, hair measures are not confounded by diurnal variation or hormonal reactivity. In an ethnically and socioeconomically diverse sample of 1286 child and adolescent twins and multiples from 672 unique families, we estimated genetic and environmental influences on hair concentrations of testosterone, DHEA, and progesterone across the period of 8-18 years of age. On average, male DHEA and testosterone were highly heritable, whereas female DHEA, progesterone, and puberty were largely influenced by environmental components. We identified sex-specific developmental windows of maximal heritability in each hormone. Peak heritability for DHEA occurred at approximately 10 years of age for males and females. Peak heritability for testosterone occurred at age 12.5 and 15.2 years for males and females, respectively. Peak heritability for male progesterone occurred at 11.2 years, while the heritability of female progesterone remained uniformly low. The identification of specific developmental windows when genetic signals for hormones are maximized has critical implications for well-informed models of hormone-behavior associations in childhood and adolescence.

The trichotillometry: a technique for hair assessment.

BACKGROUND: There are many different non-invasive or invasive techniques for studying the hair state either in the normal or diseased conditions. OBJECTIVE: A technique is used to evaluate the current hair status through setting a normal standard value or range of the epilating force of different hair follicle types in normal individuals. METHODS: The trichotillometer is used to record in grams the force exerted to epilate a single hair in different locations of scalp. RESULTS: Of all the plucked hairs from all the volunteers, the epilating force, the diameter, and the follicular length were calculated. The shear strain needed for epilating different hair types is calculated. CONCLUSION: Using the trichotillometry technique to identify the normal range of the shear strain for different hair types is important as it may aid in diagnostic, prognostic, or even therapeutic decision making for many hair diseases.

No-reference hair occlusion assessment for dermoscopy images based on distribution feature.

The presence of hair is a common quality problem for dermoscopy images, which may influence the accuracy of lesion analysis. In this paper, a novel no-reference hair occlusion assessment method is proposed according to the distribution feature of hairs in the dermoscopy image. Firstly, the image is adaptively enhanced by simple linear iterative clustering (SLIC) combined with isotropic nonlinear filtering (INF). Then, hairs are extracted from the image by an automatic threshold and meanwhile the postprocessing is used to refine the hair through re-extracting omissive hairs and filtering false hairs. Finally, the degree of hair occlusion is evaluated by an objective metric based on the hair distribution. A series of experiments was carried out on both simulated images and real images. The result shows that the proposed local adaptive hair detection method can work well on both sparse hair and dense hair, and the designed metric can effectively evaluate the degree of hair occlusion.

Performance assessment of bio-inspired systems: flow sensing MEMS hairs.

Despite vigorous growth in biomimetic design, the performance of man-made devices relative to their natural templates is still seldom quantified, a procedure which would however significantly increase the rigour of the biomimetic approach. We applied the ubiquitous engineering concept of a figure of merit (FoM) to MEMS flow sensors inspired by cricket filiform hairs. A well known mechanical model of a hair is refined and tailored to this task. Five criteria of varying importance in the biological and engineering fields are computed: responsivity, power transfer, power efficiency, response time and detection threshold. We selected the metrics response time and detection threshold for building the FoM to capture the performance in a single number. Crickets outperform actual MEMS on all criteria for a large range of flow frequencies. Our approach enables us to propose several improvements for MEMS hair-sensor design.

Effects of photoperiod on daily locomotor activity, energy expenditure, and feeding behavior in a seasonal mammal.

The objective of this study was to determine whether the previously observed effects of photoperiod on body weight in Siberian hamsters were due to changes in the daily patterns of locomotor activity, energy expenditure, and/or feeding behavior. Adult males were monitored through a seasonal cycle using an automated comprehensive laboratory animal monitoring system (CLAMS). Exposure to a short-day photoperiod (SD; 8:16-h light-dark cycle) induced a significant decline in body weight, and oxygen consumption (Vo(2)), carbon dioxide production (Vco(2)), and heat production all decreased reaching a nadir by 16 wk of SD. Clear daily rhythms in locomotor activity, Vo(2), and Vco(2) were observed at the start of the study, but these all progressively diminished after prolonged exposure to SD. Rhythms in feeding behavior were also detected initially, reflecting an increase in meal frequency but not duration during the dark phase. This rhythm was lost by 8 wk of SD exposure such that food intake was relatively constant across dark and light phases. After 18 wk in SD, hamsters were transferred to a long-day photoperiod (LD; 16:8-h light-dark cycle), which induced significant weight gain. This was associated with an increase in energy intake within 2 wk, while Vo(2), Vco(2), and heat production all increased back to basal levels. Rhythmicity was reestablished within 4 wk of reexposure to long days. These results demonstrate that photoperiod impacts on body weight via complex changes in locomotor activity, energy expenditure, and feeding behavior, with a striking loss of daily rhythms during SD exposure.

A scoring system for coat and tail condition in ringtailed lemurs, Lemur catta.

Coat condition can be influenced by a wide variety of disorders and thus provides a useful tool for noninvasive health and welfare assessments in wild and captive animals. Using Lemur catta as an exemplar, we offer a 6-step scoring system for coat and tail condition, ranging from perfectly fluffy to half or more of body and tail being hairless. The categories are described in detail and illustrated with sample pictures from a wild population in Berenty Reserve, Madagascar. Furthermore, we elaborate on intermediate conditions and discoloration of fur. Coat condition scoring allows the comparison between years, seasons, and the effect of toxin, disease or stress. Although this system was developed for wild L. catta, we believe it can also be of value for other species. We recommend scoring coat condition in healthy wild mammal populations to give a baseline on yearly and seasonal variations vs. deteriorating health conditions or pathology.

Coat condition of ringtailed lemurs, Lemur catta at Berenty Reserve, Madagascar: I. Differences by age, sex, density and tourism, 1996-2006.

An index of coat condition can be a non-invasive tool for tracking health and stress at population level. Coat condition in ringtailed lemurs, Lemur catta, was recorded during September-November birth seasons of 1996, 1997, 1999, and 2001-2006 at Berenty Reserve, Madagascar. Condition was scored on a scale from 0: full, fluffy coat with guard hairs present, to 5: half or more of body hairless. Adult males did not differ overall from adult females. Coats were worse in adults than in 2-year-old subadults; 1-year-old juveniles were intermediate. Mothers and adult males lost coat condition as the season progressed: non-mother females maintained condition. Years 1999-2002 scored better coats than either 1996-1997 or 2003-2006. Lemurs in high population density areas had worse coats than in natural forest, but tourist presence had less effect than density. Monitoring coat condition in an apparently healthy population reveals differences between population segments, and in a forest fragment with limited immigration or emigration it can track progressive changes, correcting impressions of progressive improvement or degradation over time. Above all it gives a baseline for response to climate changes or eventual pathology.

Ideal men: masculinity and decline in seventeenth-century Spain.

This article examines how the experience and critique of their country's decline led Spaniards to craft a distinct discourse of masculinity in the seventeenth century. As they self-consciously examined Spain's crisis and offered political and economic solutions, these same writers also offered a scathing critique of standards of masculinity. Using the figure of the ideal nobleman as a case study, the article examines how moralists, arbitristas, and hagiographers constructed a dynamic code of manhood linked to questions of productivity, male chastity, and military performance. Further, it argues that this discourse was ultimately nostalgic and failed to adapt itself to the circumstances of the seventeenth century.

Pilot study using hair nicotine feedback to reduce Latino children's environmental tobacco smoke exposure.

PURPOSE: This was a pilot study to assess the usability and impact of a feedback-based environmental tobacco smoke (ETS) reduction approach for Latino families. DESIGN: A one-group, pre-post design was used. METHODS: Information from hair samples from children analyzed for nicotine was used to create three feedback versions presented in a counterbalanced fashion. The intervention was conducted by a promotora in the participants' homes, with mailed materials and over the phone. Fifty Latino parent-child pairs were recruited. Parents were Spanish-speaking smoking adults (typically the mother) who reported exposing their children to ETS. Intervention efforts included home visits to provide nicotine feedback and counseling, two mailers presenting alternative versions of the feedback, and a supportive telephone call delivered over a 6-week period. Pre-post assessments conducted by a bicultural measurement technician measured parent reports of children's ETS exposure and children's hair nicotine. Parents' liking/usability of the three feedback formats was measured at the post-assessment. Paired t-tests assessed pre-post changes in exposure outcomes. RESULTS: Parents' reports of exposure and children's hair nicotine levels showed statistically significant reductions. Parents liked all three feedback formats, particularly a comparative graphic format. CONCLUSIONS: Consistency of the positive findings suggests that this feedback approach to ETS reduction warrants further study with a more rigorous design.

Pharmacologic interventions in aging hair.

The appearance of hair plays an important role in people's overall physical appearance and self-perception. With today's increasing life-expectations, the desire to look youthful plays a bigger role than ever. The hair care industry has become aware of this and is delivering active products directed towards meeting this consumer demand. The discovery of pharmacological targets and the development of safe and effective drugs also indicate strategies of the drug industry for maintenance of healthy and beautiful hair. Hair aging comprises weathering of the hair shaft, decrease of melanocyte function, and decrease in hair production. The scalp is subject to intrinsic and extrinsic aging. Intrinsic factors are related to individual genetic and epigenetic mechanisms with interindividual variation: prototypes are familial premature graying, and androgenetic alopecia. Currently available pharmacologic treatment modalities with proven efficacy for treatment of androgenetic alopecia are topical minoxidil and oral finasteride. Extrinsic factors include ultraviolet radiation and air pollution. Experimental evidence supports the hypothesis that oxidative stress also plays a role in hair aging. Topical anti-aging compounds include photoprotectors and antioxidants. In the absence of another way to reverse hair graying, hair colorants remain the mainstay of recovering lost hair color. Topical liposome targeting for melanins, genes, and proteins selectively to hair follicles are currently under investigation.

Assessment of pubertal development in Egyptian girls.

Puberty is a significant event of human growth and maturation associated with marked physiological and psychological changes. The aim of this study was to assess normal pubertal development in Egyptian girls to define normal, precocious and delayed puberty. The present study included a cross-sectional sample of 1,550 normal Egyptian girls of high and middle socioeconomic class living in Cairo. Their ages ranged from 6.5 to 18.5 years. Pubertal assessment was made according to Tanner staging. The mean menarcheal age (MMA) was estimated using probit analysis. Weight and height were measured and body mass index (BMI) was calculated. The mean age at breast bud stage (B2) was 10.71+/-1.6, pubic hair stage (PH2) was 10.46+/-1.36, while axillary hair stage (A2) was 11.65+/-1.62 and MMA was 12.44 years. The mean age at attainment of puberty was compared with those of other Egyptian studies and other populations. Girls of the present study started pubertal development and achieved menarche earlier than those of previous Egyptian studies confirming a secular trend. Differences between the present study and other worldwide studies can be attributed to various genetic, racial, geographical, nutritional, and secular trend factors.

Elements in the hair of non-mining workers of a lignite open mine in Neyveli.

Trace elements are analyzed in the human scalp hair to assess the extent of body burden of pollution. The levels of seven elements (Cd, Cr, Cu, Mn, Ni, Pb and Zn) were determined in the hair of fishermen from Pondicherry, students and businessmen from Madras and non-mining workers from Neyveli lignite open mine. When compared between them, significantly high concentrations of Cd in the non-mining workers from Neyveli and Pb in both the students and businessmen from Madras were observed, thereby indicating environmental source of Cd and Pb pollution. The low Zn level was observed in the fishermen indicating their low nutritional source. In addition to the different residential areas, age, diet, smoking habit and family income of subjects are other factors influencing the concentrations of elements in the hair.

Self-assessment of sexual maturation in Thai children by Tanner photograph.

Assessment of sexual maturation in adolescence is crucially important in clinical practice, because the possibility of concealed disease during the earlier period of child development needs to be detected. However, to undress children sometimes is problematic and unethical in several countries. Therefore, in this study the authors evaluated the concordance between children's self-assessment by Tanner photograph with a written description, and examination by pediatricians. One hundred and ninety four children (100 girls, 94 boys), aged 7-15 years, were recruited in this study. The outcome demonstrated that the two processes of investigation were in good concord: the weight kappa of 0.76 and 0.79 for the breast stage (B) and pubic hair stage (PH), respectively, in girls. In boys, the weight kappa were 0.59 and 0.73 for genital stage (G) and pubic hair (PH) stage, respectively. However, the weight kappa for genital stage was improved after the subjects were provided more time to examine themselves before choosing the photograph. In girls, the mean chronological age (CA) for B stage II, III, IV was 10.4+/-1.3, 12.5+/-1.3, 13.6+/-0.7 years and for PH stage II, III, IV was 11.9+/-1.4, 12.9+/-1.2, 13.5+/-0.9 years. The normal CA for the onset of puberty in girls was between 7.8-13.0 years. In boys, the mean CA for G stage II, III, IV was 11.3+/-1.7, 12.4+/-1.2, 13.2+/-1.2 years, and for PH II, III, IV was 12.2+/-1.3, 13.1+/-1.0, 13.9+/-1.7 years. The normal CA for the onset of puberty in boys was 7.9-14.7 years. In addition, the authors constructed the normal value for penile length in Thai boys, aged between 9-15 years, to be used as a reference. Therefore, this study demonstrated a good concordance between the self-assessment by Tanner photograph and examination by pediatricians. This can be applied for use in filed research, school screening and clinical practice.