Genome-wide characterisation of HD-Zip transcription factors and functional analysis of PbHB24 during stone cell formation in Chinese white pear (Pyrus bretschneideri).

BACKGROUND: The homodomain-leucine zipper (HD-Zip) is a conserved transcription factor family unique to plants that regulate multiple developmental processes including lignificaion. Stone cell content is a key determinant negatively affecting pear fruit quality, which causes a grainy texture of fruit flesh, because of the lignified cell walls. RESULTS: In this study, a comprehensive bioinformatics analysis of HD-Zip genes in Chinese white pear (Pyrus bretschneideri) (PbHBs) was performed. Genome-wide identification of the PbHB gene family revealed 67 genes encoding PbHB proteins, which could be divided into four subgroups (I, II, III, and IV). For some members, similar intron/exon structural patterns support close evolutionary relationships within the same subgroup. The functions of each subgroup of the PbHB family were predicted through comparative analysis with the HB genes in Arabidopsis and other plants. Cis-element analysis indicated that PbHB genes might be involved in plant hormone signalling and external environmental responses, such as light, stress, and temperature. Furthermore, RNA-sequencing data and quantitative real-time PCR (RT-qPCR) verification revealed the regulatory roles of PbHB genes in pear stone cell formation. Further, co-expression network analysis revealed that the eight PbHB genes could be classified into different clusters of co-expression with lignin-related genes. Besides, the biological function of PbHB24 in promoting stone cell formation has been demonstrated by overexpression in fruitlets. CONCLUSIONS: This study provided the comprehensive analysis of PbHBs and highlighted the importance of PbHB24 during stone cell development in pear fruits.

The Autumn Years: Age Differences in Preferences for Sexually Dimorphic Faces.

Life history theory proposes that it is adaptive for older people to shift investment away from reproductive effort (such as mating) to survivorship. However, it remains unclear whether the shift is also present at the psychological level. We investigated this question by comparing preferences for mate choice-relevant cues, sexually dimorphic facial images, between older (60 years and older, n = 92) and younger adults (18-40 years, n = 86). Results showed that older adults had significantly smaller preferences for sexually dimorphic faces of both sexes than young adults. Specifically, both older men and women showed no significant preferences for sexually dimorphic traits when judging opposite-sex faces, and smaller preferences for masculine male faces and feminine female faces when judging same-sex faces. Young adults generally showed strong preferences for masculine male faces and feminine female faces. In Study 2, we confirmed that the absent/reduced preferences in older adults for sexually dimorphic faces did not result from poor visual ability. The smaller preferences for sexually dimorphic facial cues in older adults compared to young adults suggest that older adults may shift away from mating-oriented psychology as they become less fertile.

Exogenous testosterone decreases men's sensitivity to vocal cues of male dominance.

Assessing dominance is important for effective social interactions, and prior research suggests that testosterone is associated with men's dominance perceptions. The present study tested for a causal effect of exogenous testosterone on men's sensitivity to vocal cues of other men's dominance, an important parameter in male-male competition across species. One hundred and thirty-nine Chinese men received a single dose (150 mg) of testosterone or placebo gel in a double-blind, placebo-controlled, between-participant design. Participants reported their own dominance and judged other men's dominance from voices. Men's dominance sensitivity was significantly weaker in the testosterone group compared to those in the placebo group. Moreover, men's dominance sensitivity was negatively associated with their self-reported dominance in our Chinese sample, consistent with findings from Western populations. These results indicate that exogenous testosterone has a causal effect in decreasing men's dominance sensitivity, consistent with the Challenge Hypothesis, suggesting that the fluctuation of testosterone concentration mediates individuals' behaviors. Additionally, the present study could motivate further work on vocal assessment in the context of competition in humans and other species.

A Data-Driven Test for Cross-Cultural Differences in Face Preferences.

Previous research has shown strong cross-cultural agreement in facial attractiveness judgments. However, these studies all used a theory-driven approach in which responses to specific facial characteristics are compared between cultures. This approach is constrained by the predictions that can be derived from existing theories and can therefore bias impressions of the extent of cross-cultural agreement in face preferences. We directly addressed this problem by using a data-driven, rather than theory-driven, approach to compare facial attractiveness judgments made by Chinese-born participants who were resident in China, Chinese-born participants currently resident in the UK, and UK-born and UK-resident White participants. Analyses of the principal components along which faces naturally varied suggested that Chinese and White UK participants used face information in different ways, at least when judging women's facial attractiveness. In other words, the data-driven approach used in this study revealed some cross-cultural differences in face preferences that were not apparent in studies using theory-driven approaches.

No Compelling Evidence that Preferences for Facial Masculinity Track Changes in Women's Hormonal Status.

Although widely cited as strong evidence that sexual selection has shaped human facial-attractiveness judgments, findings suggesting that women's preferences for masculine characteristics in men's faces are related to women's hormonal status are equivocal and controversial. Consequently, we conducted the largest-ever longitudinal study of the hormonal correlates of women's preferences for facial masculinity ( N = 584). Analyses showed no compelling evidence that preferences for facial masculinity were related to changes in women's salivary steroid hormone levels. Furthermore, both within-subjects and between-subjects comparisons showed no evidence that oral contraceptive use decreased masculinity preferences. However, women generally preferred masculinized over feminized versions of men's faces, particularly when assessing men's attractiveness for short-term, rather than long-term, relationships. Our results do not support the hypothesized link between women's preferences for facial masculinity and their hormonal status.

No clear evidence for correlations between handgrip strength and sexually dimorphic acoustic properties of voices.

OBJECTIVES: Recent research on the signal value of masculine physical characteristics in men has focused on the possibility that such characteristics are valid cues of physical strength. However, evidence that sexually dimorphic vocal characteristics are correlated with physical strength is equivocal. Consequently, we undertook a further test for possible relationships between physical strength and masculine vocal characteristics. METHODS: We tested the putative relationships between White UK (N = 115) and Chinese (N = 106) participants' handgrip strength (a widely used proxy for general upper-body strength) and five sexually dimorphic acoustic properties of voices: fundamental frequency (F0), fundamental frequency's SD (F0-SD), formant dispersion (Df), formant position (Pf), and estimated vocal-tract length (VTL). RESULTS: Analyses revealed no clear evidence that stronger individuals had more masculine voices. CONCLUSIONS: Our results do not support the hypothesis that masculine vocal characteristics are a valid cue of physical strength.

Women's facial attractiveness is related to their body mass index but not their salivary cortisol.

OBJECTIVES: Although many theories of human facial attractiveness propose positive correlations between facial attractiveness and measures of actual health, evidence for such correlations is somewhat mixed. Here we sought to replicate a recent study reporting that women's facial attractiveness is independently related to both their adiposity and cortisol. METHODS: Ninety-six women provided saliva samples, which were analyzed for cortisol level, and their height and weight, which were used to calculate their body mass index (BMI). A digital face image of each woman was also taken under standardized photographic conditions and rated for attractiveness. RESULTS: There was a significant negative correlation between women's facial attractiveness and BMI. By contrast, salivary cortisol and facial attractiveness were not significantly correlated. CONCLUSIONS: Our results suggest that the types of health information reflected in women's faces include qualities that are indexed by BMI but do not necessarily include qualities that are indexed by cortisol. Am. J. Hum. Biol. 28:352-355, 2016. © 2015 Wiley Periodicals, Inc.

Testosterone administration decreases sensitivity to angry facial expressions in healthy males: A computational modeling approach.

Previous research indicates that higher testosterone levels are related to increased aggressive and dominant behaviors, particularly in males. One possible mechanism for these hormone-behavior associations could involve threat perception. However, the causal influence of testosterone on men's recognition of threatening facial expressions remains unknown. Here, we tested the causal effect of exogenous testosterone on men's sensitivity to facial threat by combining a psychophysical task with computational modeling. We administered a single dose (150 mg) of testosterone or placebo gel to healthy young men (n = 120) in a double-blind, placebo-controlled, between-participant design. Participants were presented with morphed emotional faces mixing anger/fear and neutral expressions and made judgments about the emotional expression. Across typical regression analysis, signal detection analysis, and drift diffusion modeling, our results consistently showed that individuals who received testosterone (versus placebo) exhibited a lower perceived sensitivity to angry facial expressions. But we observed no significant effects of testosterone administration on fearful facial expressions. The findings indicate that testosterone attenuates sensitivity to facial threat, especially angry facial expressions, which could lead to a misestimation of others' dominance and an increase in one's own aggressive and dominant behaviors.

Face Blindness in Children and Current Interventions.

Children with prosopagnosia, also known as face blindness, struggle to recognize the faces of acquaintances, which can have a negative impact on their social interactions and overall functioning. This paper reviews existing research on interventions for children with prosopagnosia, including compensatory and remedial strategies, and provides a summary and comparison of their effectiveness. However, despite the availability of these interventions, their effectiveness remains limited and constrained by various factors. The lack of a widely accepted treatment for children with prosopagnosia emphasizes the need for further research to improve intervention strategies. Last, three future research directions were proposed to improve interventions for prosopagnosia, including ecological approaches, the social challenges faced by children, and new potential intervention methods.

Hidden faces, altered perceptions: the impact of face masks on interpersonal perception.

The pandemic has made wearing masks commonplace, prompting researchers to investigate their effects on interpersonal perception. Findings indicate masks obstruct face identification and expression recognition, with lower face cues being most affected. When judging attractiveness, masks can enhance the appeal of less attractive faces, but reduce the appeal of more attractive faces. Trust and speech perception outcomes are inconclusive. Future studies could focus on individual differences in how masks influence our perception of others.

Hearing the physical condition: The relationship between sexually dimorphic vocal traits and underlying physiology.

A growing amount of research has shown associations between sexually dimorphic vocal traits and physiological conditions related to reproductive advantage. This paper presented a review of the literature on the relationship between sexually dimorphic vocal traits and sex hormones, body size, and physique. Those physiological conditions are important in reproductive success and mate selection. Regarding sex hormones, there are associations between sex-specific hormones and sexually dimorphic vocal traits; about body size, formant frequencies are more reliable predictors of human body size than pitch/fundamental frequency; with regard to the physique, there is a possible but still controversial association between human voice and strength and combat power, while pitch is more often used as a signal of aggressive intent in conflict. Future research should consider demographic, cross-cultural, cognitive interaction, and emotional motivation influences, in order to more accurately assess the relationship between voice and physiology. Moreover, neurological studies were recommended to gain a deeper understanding of the evolutionary origins and adaptive functions of voice modulation.

Using relative-speed-of-processing to explain the shielding function of task rules.

In choice reaction tests, applying task rules instead of responding associatively can help participants shield against interference from distractors. However, the mechanism of such shielding functions remains unclear. Through four experiments, we show how the shielding function can be explained by the relative-speed-of-processing theory. Experiment 1A demonstrated that applying task rules can reduce the relative processing advantage of the distractor by facilitating the target processing speed, thereby eliminating the interference effect. In Experiment 1B and 1C, we manipulated the relative processing advantage between targets and distractors by adjusting the temporal sequence of the presence of the targets and distractors: stimuli appearing first would gain more relative processing advantage. The results showed that when the relative processing advantage of a distractor was large enough, applying task rules cannot help participants shield against the interference. Contrarily, when the relative processing advantage of the distractor was small, even without applying task rules, participants did not experience the interference. In Experiment 2, we directly manipulated the processing speed of the targets and the distractor, so that participants who responded associatively would facilitate target processing speed, but participants who applied task rules would not. Contrary to previous studies but in line with our prediction, in Experiment 2, only participants who applied task rules had interference effects. Our results suggested that applying the task rule might not help shield against the interference directly. Instead, applying task rules improves target processing speed, which in turn reduces the relative processing advantage of the distractor and eliminates the interference.

Task switching in old participants: A potential interplay between strategy and cognitive ability.

Task-switching cost is highly reliable in old participants. However, in a Stroop-switching paradigm that compared old musicians with old non-musicians (Experiment 1A), task-switching costs were not consistent. For non-musicians, the task-switching costs were significant in the congruent and neutral trials, but not in the incongruent trials. For musicians, the task-switching costs disappeared completely. We suspected that besides following task rules, old participants might also apply a stimulus-based strategy called the target-first strategy. In Experiment 1B and 2, participants in Experiment 1A were invited again to perform two more Stroop-switching paradigms. To encourage the participants to use task rules, in Experiment 1B we removed the neutral trials but found the same results as in Experiment 1A. In Experiment 2, when inserting a cue-target interval in the Stroop-switching paradigm, both musicians and non-musicians produced reliable task-switching costs in all trial conditions. Note that younger participants had reliable task-switching costs in Experiment 1B and 2. We suggest that older participants preferred the target-first strategy to the task rules-based strategy because the former was easy to implant although it was less flexible. Besides task-switching costs, we found that old musicians had less interference effect than old non-musicians in Experiment 1B. In all three experiments, old musicians had shorter RTs than old non-musicians, which might be due to differences in strategies apart from cognitive abilities. We propose that without considering the strategy preference, some previous studies might misestimate the difference between old and young participants in terms of task-switching performance and interference control.

Time for a true display of skill: Top players in League of Legends have better executive control.

Research into the effects of action video gaming on cognition has largely relied on self-reported action video game experience and extended video game training. Only a few studies have focused on participants' actual gaming skills. However, whether superior players and average players have different executive control is still not fully demonstrated. This study had top-ranking League of Legends players (global top 0.17%; N = 35) and average-ranking League of Legends players (N = 35) perform two cognitive tasks that aimed to measure three aspects of executive functioning: cognitive flexibility, interference control, and impulsive control. We controlled self-reported gaming experience, so that top-ranking players and average-ranking players had similar years of play and hours of play per week. We found that compared to a group of average players, top players showed smaller task-switching costs and smaller response-congruency effects in a Stroop-switching test. In a continuous performance test, top players indicated higher hit rates and lower false alarm rates as compared to average players. These findings suggest that top players have better cognitive flexibility and more accurate control of interference in the context of task-switching. Moreover, top players exhibit better impulsive control. The present study provides evidence that players' gaming skills rather than gaming experience are related to cognitive abilities, which may explain why previous studies on self-reported gaming experience and those assessing supervised training and cognitive performance have shown inconsistent results.

Single dose testosterone administration increases men's facial femininity preference in a Chinese population.

Sex hormones are thought to influence human mate preferences. Previous studies have reported mixed results regarding the association between men's testosterone levels and their mate preferences. The present study investigated the effect of testosterone administration on men's facial femininity preference. Heterosexual Chinese male participants (n = 140) received a single dose of 150 mg testosterone or placebo gel in a double-blind, placebo-controlled, between-participant design. Results showed that Chinese men demonstrated general preferences for feminized women's faces, consistent with previous results from the Western population. More importantly, men showed stronger attraction to femininity in women's faces three hours after testosterone administration than at the beginning of the session. In the placebo group, no significant change in facial femininity preferences was found between time points. These results indicate that exogenous testosterone increases men's facial femininity preferences in a Chinese population.

Facial Attractiveness of Chinese College Students With Different Sexual Orientation and Sex Roles.

Facial attractiveness refers to a positive and joyful emotional experience induced by the face of a target person and the extent to which other people are driven to be close to their wishes. Since the 1970s, face attractiveness has gradually emerged in western psychological research, but most of the studies were confined to heterosexuals. More recently, some scholars have pointed out that sexual orientation may affect the judgment of facial attractiveness of individuals. Based on previous literature, this study proposed to explore the different facial attractiveness of individuals with different sexual orientations and sexual roles. Participants in this study were divided into two types (according to sexual orientation and sexual role) by the Sex Role Inventory for College Students (CSRI). Also, the eye-tracking technique was used to record the path of eye movements, where face images were manipulated by sexual dimorphism clues. The results showed that (1) compared to heterosexual men, homosexual men were significantly more likely to choose masculine faces as more attractive faces in paired faces; (2) male homosexuals are likely to have the feminization bias, and female homosexuals are likely to have the masculinization bias; and (3) the masculine faces are more attractive than feminine faces to participants whose sex role is feminine type and androgynous type.

A data-driven study of Chinese participants' social judgments of Chinese faces.

Social judgments of faces made by Western participants are thought to be underpinned by two dimensions: valence and dominance. Because some research suggests that Western and Eastern participants process faces differently, the two-dimensional model of face evaluation may not necessarily apply to judgments of faces by Eastern participants. Here we used a data-driven approach to investigate the components underlying social judgments of Chinese faces by Chinese participants. Analyses showed that social judgments of Chinese faces by Chinese participants are partly underpinned by a general approachability dimension similar to the valence dimension previously found to underpin Western participants' evaluations of White faces. However, we found that a general capability dimension, rather than a dominance dimension, contributed to Chinese participants' evaluations of Chinese faces. Thus, our findings present evidence for both cultural similarities and cultural differences in social evaluations of faces. Importantly, the dimension that explained most of the variance in Chinese participants' social judgments of faces was strikingly similar to the valence dimension previously reported for Western participants.

No compelling evidence that more physically attractive young adult women have higher estradiol or progesterone.

Putative associations between sex hormones and attractive physical characteristics in women are central to many theories of human physical attractiveness and mate choice. Although such theories have become very influential, evidence that physically attractive and unattractive women have different hormonal profiles is equivocal. Consequently, we investigated hypothesized relationships between salivary estradiol and progesterone and two aspects of women's physical attractiveness that are commonly assumed to be correlated with levels of these hormones: facial attractiveness (N = 249) and waist-to-hip ratio (N = 247). Our analyses revealed no compelling evidence that women with more attractive faces or lower (i.e., more attractive) waist-to-hip ratios had higher levels of estradiol or progesterone. One analysis did suggest that women with more attractive waist-to-hip ratios had significantly higher progesterone, but the relationship was weak and the relationship not significant in other analyses. These results do not support the influential hypothesis that between-women differences in physical attractiveness are related to estradiol and/or progesterone.

Does the Interaction Between Cortisol and Testosterone Predict Men's Facial Attractiveness?

Although some researchers have suggested that the interaction between cortisol and testosterone predicts ratings of men's facial attractiveness, evidence for this pattern of results is equivocal. Consequently, the current study tested for a correlation between men's facial attractiveness and the interaction between their cortisol and testosterone levels. We also tested for corresponding relationships between the interaction between cortisol and testosterone and ratings of men's facial health and dominance (perceived traits that are correlated with facial attractiveness in men). We found no evidence that ratings of either facial attractiveness or health were correlated with the interaction between cortisol and testosterone. Some analyses suggested that the interaction between cortisol and testosterone levels may predict ratings of men's facial dominance, however, with testosterone being more closely related to facial dominance ratings among men with higher cortisol. Our results suggest that the relationship between men's facial attractiveness and the interaction between cortisol and testosterone is not robust.

Interrelationships Among Men's Threat Potential, Facial Dominance, and Vocal Dominance.

The benefits of minimizing the costs of engaging in violent conflict are thought to have shaped adaptations for the rapid assessment of others' capacity to inflict physical harm. Although studies have suggested that men's faces and voices both contain information about their threat potential, one recent study suggested that men's faces are a more valid cue of their threat potential than their voices are. Consequently, the current study investigated the interrelationships among a composite measure of men's actual threat potential (derived from the measures of their upper-body strength, height, and weight) and composite measures of these men's perceived facial and vocal threat potential (derived from dominance, strength, and weight ratings of their faces and voices, respectively). Although men's perceived facial and vocal threat potential were positively correlated, men's actual threat potential was related to their perceived facial, but not vocal, threat potential. These results present new evidence that men's faces may be a more valid cue of these aspects of threat potential than their voices are.