Time under control: time perspective and desire for control in substance use

Psychometric Properties of the Chinese Version of 20-Item Zimbardo Time Perspective Inventory (C-ZTPI-20) in Chinese Adolescent Population

Background

This study assesses the psychometric properties of the Chinese version of the Zimbardo Time Perspective Inventory (C-ZTPI-20) in an adolescent population.

Methods

The investigation encompasses a sample of 2634 middle school students from China and aims to evaluate the instrument's reliability, structural validity, measurement invariance, criterion validity, and network structure attributes.

Results

First, descriptive analysis revealed satisfactory reliabilities for four out of five C-ZTPI-20 dimensions, with Present Fatalistic (PF) exhibiting relatively low reliability. Moreover, Confirmatory Factor Analysis (CFA) supported the 5-dimensional structure across all samples and sexes, albeit with a modest Tucker-Lewis Index (TLI) for girls. Furthermore, measurement invariance analysis underscores unbiased assessment across sexes. Sex differences emerge in the Present Hedonistic (PH) dimension, where boys showed higher scores. Furthermore, criteria validity analysis revealed that Past Positive (PP) and Future (F) were positively associated with extraversion, agreeableness, conscientiousness, openness, grit, and mental health, while they were negatively associated with neuroticism. Past Negative (PN) and PF showed inverse trends, while PH perspective demonstrated complex, varied correlations with these psychological traits, underscoring the multifaceted nature of time perspectives. Finally, network analysis revealed positive inter-correlations within dimensions and significant edge differences between sexes, particularly in inter-dimension connections. Despite differing rankings, the most central and marginal items remained consistent between boys and girls in network models.

Conclusion

These findings contribute to understanding the C-ZTPI-20's effectiveness in assessing adolescent time perspectives and inform interventions promoting psychological well-being and coping strategies.

Time perspective affects daily time use and daily functioning in individuals with Schizophrenia Spectrum Disorders: Results from the multicentric DiAPAson study

Time perspective (TP) influences various aspects of human life. We aimed to explore the associations between TP, daily time use, and levels of functioning among 620 patients (313 residential patients and 307 outpatients) with a diagnosis of Schizophrenia Spectrum Disorders (SSD) recruited from 37 different centres in Italy. The Brief Psychiatric Rating Scale and the Specific Levels of Functioning (SLOF) were used to assess psychiatric symptoms severity and levels of functioning. Daily time use was assessed using an ad hoc paper and pencil Time Use Survey. The Zimbardo Time Perspective Inventory (ZTPI) was used to assess TP. Deviation from Balanced Time Perspective (DBTP-r) was used as an indicator of temporal imbalance. Results showed that the amount of time spent on non-productive activities (NPA) was positively predicted by DBTP-r (Exp(β): 1.36; p .003), and negatively predicted by the Past-Positive (Exp(β): 0.80; p .022), Present-Hedonistic (Exp(β): 0.77; p .008), and Future (Exp(β): 0.78; p .012) subscales. DBTP-r significantly negatively predicted SLOF outcomes (p .002), and daily time use, in particular the amount of time spent in NPA and Productive Activities (PA), mediated their association. Results suggested that rehabilitative programs for individuals with SSD should consider fostering a balanced time perspective to reduce inactivity, increase physical activity, and promote healthy daily functioning and autonomy.

Present hedonism and future time perspectives predicting hypersexuality and problematic pornography use

The Time Perspective (TP) theory (i.e., the psychological experience regarding time) was often examined in association with different addictive behaviors, and the different TPs (i.e., Past Positive, Past Negative, Present Hedonistic, Present Fatalistic, and Future TPs) demonstrated different relationship patterns with them. However, most studies were conducted in relation to substance use-related disorders, leaving crucial knowledge gaps concerning the associations between TPs and potential behavioral addictions. The aim of the present study was to examine the associations between the five TP dimensions, hypersexuality, and problematic pornography use (PPU), considering potential gender differences. Participants from two independent samples (N₁ = 554; N₂ = 453) completed a self-report survey on TPs and sexual behaviors. Structural equation modeling results indicated that the Present Hedonistic TP had a positive, moderate, and the Future TP had a negative, weak association with hypersexuality in both samples. Only the Present Hedonistic TP had a significant, positive, weak-to-moderate association with PPU across the samples. The explained variances of the models were higher in case of hypersexuality (28 and 27%, respectively), than in case of PPU (1 and 14%, respectively). No significant gender differences were observed. In line with previous findings concerning other predictors of hypersexuality and PPU, the results of the present study suggest that hypersexuality and PPU may differ from each other in terms of their TP background. Yet, present hedonism, which is related to impulsivity, may play an important role in both problematic sexual behaviors, suggesting that interventions focusing on this TP might be successful in reducing hypersexuality and PPU.

Self-Control, Consideration of Future Consequences, and Internet Addiction among Chinese Adolescents: The Moderating Effect of Deviant Peer Affiliation

Although a large number of studies have indicated that self-control was an important predictive factor for adolescent internet addiction, the moderating and mediating mechanisms underlying this relationship remain unclear. To address this research gap, the present study, according to social learning theory and the organism–environment interaction theory, tested whether consideration of future consequences mediated the relation between self-control and adolescent internet addiction and whether deviant peer affiliation moderated the relationship between consideration of future consequences and internet addiction. Using longitudinal tracking (two-time points and the interval is 6 months). Three middle schools in Guangzhou were randomly selected. The participants were 1182 students ranging in age from 12 to 15 years (average age: 14.16, SD = 1.29) from three middle schools in Guangzhou (651 boys and 531 girls) in Guangdong Province. Results showed that consideration of future consequences mediated the relationship between self-control and internet addiction. Furthermore, the relationship between future consequence consideration and internet addiction was moderated by deviant peer affiliation. These findings highlighted the potential mediating role of consideration of future consequences in linking self-control to adolescent internet addiction. We also found high deviant peer affiliation weakens the protective effect of future consequence consideration on Internet addiction. This study may provide support for adolescent Internet addiction prevention and have some educational implications.

Time Perspective and Substance Use: An Examination Across Three Adolescent Samples

Time perspective is conceptualized as a multidimensional construct that assesses individuals' feelings and thoughts about the past, present, and future. The current study examined relationships between feelings (time attitudes) and thoughts (time orientation) about time and substance use behaviors across three adolescent samples. Participants included a high-risk sample of adjudicated youth (N=124; M age =15.54, SD=1.69; 51.61% female) and two general population school samples (N=777; M age =15.82, SD=1.23; 53.41% female; N=1873; M age =15.87, SD=1.28; 52.22% female). Cross-sectional survey data were collected from samples in schools during 2010, 2016, and 2011, respectively. Poisson and negative binomial regression analyses indicated that overall, more positive feelings about time were associated with fewer substances used and, conversely, more negative feelings about time were associated with more substances used. These findings were particularly salient for participants with stronger positive and negative feelings toward the past and present time periods. Further, across the three samples, adolescents with a balanced time orientation (i.e., equal emphasis on all three time periods) generally reported less substance use than individuals who emphasized only one or two time periods. Findings highlight relationships between time perspective dimensions and substance use across diverse samples and illustrate opportunities for adapting time perspective-based substance use interventions for adolescents.

Neuroanatomical substrates accounting for the effect of present hedonistic time perspective on risk preference: the mediating role of right posterior parietal cortex

The preference for taking risk troubles people across multiple domains including health, economics, and social well-being. Prior research has demonstrated that risk preference can be influenced by time perspective (TP). However, little is known about the neural substrates underlying the effect of TP on risk preference. Here, we used a voxel-based morphometry (VBM) method across two samples to address this question. In Sample 1, the behavioral results showed a positive correlation between present hedonistic TP (PHTP) and gambling rate (the index of risk preference), indicating the higher PHTP, the greater the preference for risk. Subsequently, the whole-brain VBM results found that gambling rate was negatively correlated with the gray matter (GM) volume of a cluster in the right posterior parietal cortex (rPPC). The PHTP score was also negatively related to the GM volume of another cluster in the rPPC. We then examined an overlapping region in the rPPC using a conjunction analysis method. The GM volume of this overlapping brain region was related to both PHTP score and gambling rate. Finally, the mediation analysis found that the GM volume of overlapping region in rPPC played a role in explaining the effect of PHTP on risk preference. This result was also reproduced and validated in another independent sample. Taken together, our findings manifest that the structural variation of rPPC can account for the influence that PHTP has upon the risk preference.

Human time perspective and its structural associations with voxel-based morphometry and gyrification

Time perspective refers to humans’ concept of integrating and evaluating temporal position and evaluation of memories, emotions, and experiences. We tested the hypothesis that different aspects of time perspective, as assessed with the Zimbardo Time Perspective Inventory (ZTPI) are related to variation of brain structure in non-clinical subjects. Analysing data from n = 177 psychiatrically healthy subjects using voxel-based morphometry with the CAT12 software package, we identified several significant (p < 0.05 FWE, cluster-level corrected) associations. The factors past negative, reflecting a negative attitude towards past events and present fatalistic, measuring a hopeless and fatalistic attitude towards future life, were both negatively associated with grey matter volumes of the anterior insula. The ZTPI factor future was negatively associated with precuneus grey matter. There was no association of ZTPI scores with gyrification using an absolute mean curvature method, a marker of early brain development. These findings provide a link between a general psychological construct of time perspective and brain structural variations in key areas related to time keeping (anterior insula) and the default mode network (precuneus), both of which overlap with variation in behavioral aspects and psychopathology.

Motivational power of future time perspective: Meta-analyses in education, work, and health

Future time perspective (FTP) may predict individual attitudes and behaviors. However, FTP research includes different FTP conceptualizations and outcomes which hinder generalizing its findings. To solve the inconsistencies in FTP research and generalize the magnitude of FTP as a driver of motivation and behavior, we conducted the first systematical synthesis of FTP relationships in three crucial life domains. Our meta-analyses of FTP studies in education (k = 28), work (k = 17), and health (k = 32) involved N = 31,558 participants, and used a conceptual model for grouping FTP constructs. To address different outcome types, we applied the Theory of Planned Behavior when coding the studies. FTP relationships with outcomes were small-to-medium, were generalizable across domains, and were strongest when the FTP construct included a mixture of cognition, behavioral intention, and affect and, in education, when the FTP measure was domain specific rather than general. There were cross-cultural differences in FTP-outcome relationships. The strength of the FTP-outcome types relationship varied for attitudes, perceived behavioral control, behavioral intention, and behaviors. The lowest effect sizes were found for FTP predicting actual behaviors in education, work, and health and between FTP and health attitudes. Theoretical implications of the findings and future research directions are discussed.

The effect of future time perspective on delay discounting is mediated by the gray matter volume of vmPFC

Although several previous studies have shown that individuals' attitude towards time could affect their intertemporal preference, little is known about the neural basis of the relation between time perspective (TP) and delay discounting. In the present study, we quantified the gray matter (GM) cortical volume using voxel-based morphometry (VBM) methods to investigate the effect of TP on delay discounting (DD) across two independent samples. For group 1 (102 healthy college students; 46 male; 20.40 ± 1.87 years), behavioral results showed that only Future TP was a significant predictor of DD, and higher scores on Future TP were related to lower discounting rates. Whole-brain analysis revealed that steeper discounting correlated with greater GM volume in the ventromedial prefrontal cortex (vmPFC) and ventral part of posterior cingulate cortex (vPCC). Also, GM volume of a cluster in the vmPFC was correlated with Future TP. Interestingly, there was an overlapping region in vmPFC that was correlated with both DD and Future TP. Region-of-interest analysis further indicated that the overlapping region of vmPFC played a partially mediating role in the relation between Future TP and DD in the other independent dataset (Group 2, 36 healthy college students; 14 male; 20.18±1.80 years). Taken together, our results provide a new perspective from neural basis for explaining the relation between DD and future TP.

Effects of time perspective and self-control on procrastination and Internet addiction

Background and aims College students experiencing stress show tendencies to procrastinate and can develop Internet addiction problems. This study investigated the structural relationship between time perspective and self-control on procrastination and Internet addiction. Methods College students (N = 377) residing in South Korea completed the following questionnaires: the Pathological Internet Use Behavior Symptom Scale for Adults, the Zimbardo Time Perspective Inventory, the Self-Control Rating Scale, and the Aitken Procrastination Inventory. The sample variance-covariance matrix was analyzed using AMOS 20.0. Results Time perspective had a direct effect on self-control and an indirect effect on Internet use and procrastination. In addition, self-control affected procrastination and Internet use. Conclusions Individuals with a present-oriented time perspective tend to evidence poorer self-control, increasing the likelihood of procrastination and Internet addiction. Individuals with a future-oriented time perspective, on the other hand, tend to have stronger self-control, decreasing their risk of procrastination and Internet addiction.

Unstuck in time: episodic future thinking reduces delay discounting and cigarette smoking

RATIONALE

Delay discounting, or the devaluation of delayed outcomes, appears to play an etiological role in tobacco and other substance-use disorders.

OBJECTIVES

No human studies to our knowledge have been designed to examine whether experimental reductions in delay discounting produce concomitant reduction in drug use.

METHODS

Using methods from prior studies on delay discounting and obesity, we examined the effects of episodic future thinking (EFT; a form of mental prospection) on delay discounting and cigarette self-administration in smokers.

RESULTS

Consistent with prior data, EFT significantly reduced both delay discounting (Cohen's d effect size = 0.65) and the number of cigarette puffs earned in a cigarette self-administration task (d = 0.58).

CONCLUSIONS

The effects of EFT on delay discounting generalize to smokers; EFT also reduces laboratory-based cigarette self-administration. Potential mechanisms of EFT's effects are discussed as well as implications of EFT for clinical treatment of substance-use disorders.

Lived Time Disturbances of Drug Addiction Therapy Newcomers. A Qualitative, Field Phenomenology Case Study at Monar-Markot Center in Poland

The aim of this study was to qualitatively assess the disturbances of lived time in individuals with multiple drug dependencies. The research was conducted at Monar-Markot Center for Humanitarian Aid in Roznowice (Poland) in 2014 through direct, non-disguised observational study in a therapeutic community setting. Overall, 10 clients with multiple drug dependencies forming a newcomers group participated in. They previously abstained from usage for negligible periods of time. The measurements included participant observation of collective time regimes at the center; group discussions; written accounts by clients; Zimbardo Time Perspective Inventory; semi-structured interviews. It was found that the clients experienced difficulties in following a strict therapeutic temporal regime, and they also showed a concomitant need to accelerate time as it passed. They also suffered an unpleasant domination by traumatic past within lived time. Their time horizons appeared significantly shortened and their planning capacity impaired, while a distant (dissociated) future was fantasized about in a realistic manner. Altogether, their disturbances of lived time consisted of the propensity to overemphasize their past dimensions at the expense of their future, while a gap between a close and a distant future appeared.

A time to be stressed? Time perspectives and cortisol dynamics among healthy adults

Perceptions of past, present, and future events may be related to stress pathophysiology. We assessed whether Time Perspective (TP) is associated with cortisol dynamics among healthy adults (N=61, Ages=18-35, M=22.9, SD=4.1) exposed to the Trier Social Stress Test (TSST). TP was measured according to two profiles: maladaptive Deviation from Balanced TP (DBTP) and adaptive Deviation from Negative TP (DNTP). Eight salivary cortisol samples were analyzed using area under the curve with respect to ground (AUCg) and to increase (AUCi). Statistic analyses involved partial correlations controlling for depressive symptoms. Results for both sexes showed that higher DBTP scores were associated with lower cortisol AUCg scores, while higher DNTP scores were associated with higher cortisol AUCg scores. These novel findings suggest that maladaptive TP profiles influence hypocortisolism, whereas adaptive TP profiles influence hypercortisolism. Thus, TP profiles may impact conditions characterized by altered cortisol concentrations.

The impact of time perspective latent profiles on college drinking: a multidimensional approach

BACKGROUND

Zimbardo and Boyd's(1) time perspective, or the temporal framework individuals use to process information, has been shown to predict health behaviors such as alcohol use. Previous studies supported the predictive validity of individual dimensions of time perspective, with some dimensions acting as protective factors and others as risk factors. However, some studies produced findings contrary to the general body of literature. In addition, time perspective is a multidimensional construct, and the combination of perspectives may be more predictive than individual dimensions in isolation; consequently, multidimensional profiles are a more accurate measure of individual differences and more appropriate for predicting health behaviors.

OBJECTIVES

The current study identified naturally occurring profiles of time perspective and examined their association with risky alcohol use.

METHODS

Data were collected from a college student sample (n = 431, mean age = 20.41 years) using an online survey. Time perspective profiles were identified using latent profile analysis.

RESULTS

Bootstrapped regression models identified a protective class that engaged in significantly less overall drinking (β = -0.254) as well as engaging in significantly less episodic high risk drinking (β = -0.274). There was also emerging evidence of a high risk time perspective profile that was linked to more overall drinking (β = 0.198) and engaging in more high risk drinking (β = 0.245), though these differences were not significant. CONCLUSIONS/IMPORTANCE: These findings support examining time perspective in a multidimensional framework rather than individual dimensions in isolation. Implications include identifying students most in need of interventions, and tailoring interventions to target temporal framing in decision-making.

Coping Skills Help Explain How Future-Oriented Adolescents Accrue Greater Well-Being Over Time

Adolescents who endorse greater levels of future orientation report greater well-being over time, but we do not know the mechanism by which this happens. The present longitudinal study examined whether both adaptive as well as maladaptive coping strategies might explain how future orientation leads to ill-being and well-being over time in young New Zealanders. A sample of 1,774 preadolescents and early adolescents (51.9 % female) aged 10-15 years at Time 1 completed a self-report survey three times with 1 year intervals in between. Longitudinal mediation path models were constructed to determine whether and how maladaptive and adaptive coping strategies at Time 2 functioned as mediators between future orientation at Time 1 and ill-being and well-being at Time 3. Results showed that future orientation predicted lower maladaptive coping, which in turn predicted lower substance use and self-harming behavior. All three well-being outcomes (i.e., happiness with weight, vitality, and sleep) were consistently predicted by future orientation, and all three pathways were mediated by both lower maladaptive and higher adaptive coping strategies (with the exception of happiness with weight, which was mediated only by lower maladaptive coping). The results suggest that several pathways by which future orientation leads to greater well-being occurs through an increased use of adaptive coping, a decreased use of maladaptive coping, or both.

Time perspective and exercise, obesity, and smoking: moderation of associations by age

PURPOSE

Time perspective, a psychological construct denoting subjective orientation to either present or future concerns, has been inconsistently associated with healthy behaviors in adults. We hypothesized that associations would be stronger in young adults, who are first developing independent attitudes, than in older adults.

DESIGN

Cross-sectional survey.

SETTING

The study was conducted in three cities in the Mid-Atlantic region.

SUBJECTS

Subjects were 790 patrons of barber and beauty shops.

MEASURES

Measures used were the Zimbardo Time Perspective Inventory future, present-fatalistic, and present-hedonistic subscales and current smoking, days per week of recreational exercise, and height and weight, by self-report.

ANALYSIS

We tested if associations between time perspective and exercise, obesity, and current smoking differed by age group (18-24 years, 25-34 years, and 35 years and older) using analysis of variance and logistic regression.

RESULTS

Higher future time perspective scores, indicating greater focus on future events, was associated with more frequent exercise, whereas higher present-fatalistic time perspective scores, indicating more hopelessness, was associated with less frequent exercise in 18- to 24-year-olds, but not in older individuals. Lower future time perspective scores, and higher present-hedonistic time perspective scores, indicating interest in pleasure-seeking, were also associated with obesity only in 18- to 24-year-olds. Current smoking was not related to time perspective in any age group.

CONCLUSION

Time perspective has age-specific associations with exercise and obesity, suggesting stages when time perspective may influence health behavior decision making.

Time perspective as a determinant of smoking cessation in four countries: Direct and mediated effects from the International Tobacco Control (ITC) 4-Country Surveys

BACKGROUND

Future oriented time perspective predicts a number of important health behaviors and outcomes, including smoking cessation. However, it is not known how future orientation exerts its effects on such outcomes, and no large scale cross-national studies have examined the question prospectively. The aim of the current investigation was to examine the relationship between time perspective and success in smoking cessation, and social cognitive mediators of the association.

METHODS

The ITC-4 is a multi-wave, four country survey (Australia, Canada, United States, United Kingdom) of current smokers (N=9772); the survey includes baseline measurements of time perspective, intentions, quit attempts, and self-reported quit status at follow-up over 8 years. We examined the predictive power of time perspective for smoking cessation, as mediated through strength of quit intentions and prior history of quit attempts.

RESULTS

Findings indicated that those smokers with a stronger future orientation at baseline were more likely to have successfully quit at follow-up. This effect was partially explained by intention-mediated effects of future orientation on quit attempts.

CONCLUSIONS

Future orientation predicts smoking cessation across four English-speaking countries; the cessation-facilitating effects of future orientation may be primarily due to future oriented individuals' motivated and sustained involvement in the quit cycle over time.

Psychometric Properties of the Hebrew Short Version of the Zimbardo Time Perspective Inventory

The purpose of this study was to develop a short Hebrew version of the Zimbardo Time Perspective Inventory that can be easily administered by health professionals in research, therapy, and counseling. First, the empirical links of time perspective (TP) to subjective well-being and health protective and health risk behaviors are reviewed. Then, a brief account of the instrument’s previous modifications is provided. Results of confirmatory factor analysis ( N = 572) verified the five-factor structure of the short version and yielded acceptable internal consistency reliability for each factor. The correlation coefficients between the five subscales of the short (20 items) and the original (56 items) instruments were all above .79, indicating the suitability of the short version for assessing the five TP factors. Support for the discriminant and concurrent validity was also achieved, largely in agreement with previous findings. Finally, limitations and future directions are addressed, and potential applications in therapy and counseling are offered.

The role of time and risk preferences in smoking inequalities: a population-based study

Heterogeneity in time and risk preferences has been proposed as one of the mechanisms involved in the educational gradient in smoking, but this mechanism has scarcely been explored empirically. Subjective scales were introduced in the 2008 French National Health, Health Care and Insurance Survey in order to elicit measures of time and risk preferences for a representative sample of 5188 men and 5684 women. Men and women were treated separately. First, logistic regressions were used to test the associations between preferences and education and between preferences and smoking. Second, nested logistic models were built to investigate the mediating role of preferences in the educational gradient in smoking, with an econometric treatment of the rescaling problem. Preference for the present and risk loving were found to be: inversely related to educational level; strongly related to each other, and; strongly associated to current smoking, even after adjustment for educational level. There was a weakening of the educational gradient after the control for preferences, which supports the role of these two preferences as partial mediators in the educational gradient in smoking. Among men, time preference was more strongly associated with smoking than risk aversion, while the reverse was found for women. We provide convincing evidence in favour of the mediating role of time preference and risk aversion in educational inequalities in smoking and highlight the connection between those two dimensions. Gender patterns are discussed and potential implications in terms of designing targeted anti-tobacco programmes are delineated.

Time perspective and smoking, obesity, and exercise in a community sample

OBJECTIVE

To examine associations between time perspective and smoking, body mass index, and exercise.

METHODS

In this community-based survey, adults reported smoking and exercise habits and weight and height and completed the Zimbardo Time Perspective Inventory.

RESULTS

Subjects (N=265) who were more future oriented reported more frequent exercise, but were more likely to smoke. Fatalistic and hedonistic present orientations were not associated with smoking, obesity, or exercise.

CONCLUSIONS

Time perspective is not consistently associated with common health behaviors in adults.

Do time perspective and sensation-seeking predict quitting activity among smokers? Findings from the International Tobacco Control (ITC) Four Country Survey

Personality factors such as time perspective and sensation-seeking have been shown to predict smoking uptake. However, little is known about the influences of these variables on quitting behavior, and no prior studies have examined the association cross-nationally in a large probability sample. In the current study it was hypothesized that future time perspective would enhance - while sensation-seeking would inhibit - quitting activity among smokers. It was anticipated that the effects would be similar across English speaking countries. Using a prospective cohort design, this cross-national study of adult smokers (N=8845) examined the associations among time perspective, sensation-seeking and quitting activity using the first three waves of data gathered from the International Tobacco Control Four Country Survey (ITC-4), a random digit dialed telephone survey of adult smokers from the United Kingdom, United States, Canada and Australia. Findings revealed that future time perspective (but not sensation-seeking) was a significant predictor of quitting attempts over the 8-month follow-up after adjusting for socio-demographic variables, factors known to inhibit quitting (e.g., perceived addiction, enjoyment of smoking, and perceived value of smoking), and factors known to enhance quitting (e.g., quit intention strength, perceived benefit of quitting, concerns about health effects of smoking). The latter, particularly intention, were significant mediators of the effect of time perspective on quitting activity. The effects of time perspective on quitting activity were similar across all four English speaking countries sampled. If these associations are causal in nature, it may be the case that interventions and health communications that enhance future-orientation may foster more quit attempts among current smokers.