Master of Science (MS), Wright State University, 2007, Human Factors and Industrial/Organizational Psychology MS

The purpose of the present study was to examine the effects of feedback types (i.e., outcome, process, and task feedback), feedback propensities, and their interactions on task performance in an attempt to determine, first, which types of feedback produced better task performance and, second, how feedback propensities influenced relationships between feedback type and performance. Process feedback and task feedback were expected to interact in their effects on task performance. In addition, I predicted that external feedback propensity would moderate the effects of process feedback on performance and initial task performance would moderate the effects of internal feedback propensity on task performance. However, none of the hypotheses were directly supported. Overall, the current study demonstrated support for the proposition that feedback does not consistently improve performance. Instead, findings showed that feedback has highly variable effects on performance. Task feedback improved performance, process feedback did not affect performance, and outcome feedback seemed to debilitate performance over time.

Doctor of Philosophy, University of Akron, 2017, Psychology-Industrial/Organizational

Simulation and gaming have become ubiquitous in training curricula, especially in support of military operations. These capabilities provide low-cost, low-risk pedagogical opportunities, and game and simulation-based training (SBT) offer high-fidelity, adaptable and relevant learning experiences for more effective and enduring training. Feedback, and specifically real-time feedback, is a learning tool that can enhance SBT outcomes by giving trainees immediate, personalized performance information and guidance to trainees. This study examined the use of dynamic, real-time visual feedback displays on SBT effectiveness in a military training environment. Three different feedback schedules were introduced as novel feedback interventions in a custom-built SBT teaching novice pilots to fly a generic fighter aircraft. The faded condition contained high-intrusion feedback in the first training block, followed by medium-intrusion feedback in the second block and low-intrusion feedback in the final block. The increasing condition contained the opposite schedule, with low-intrusion feedback in the first training block, medium-intrusion feedback in the second block and high-intrusion feedback in the last block. The static condition contained both low and medium-intrusion feedback throughout training. These schedules were compared against a control condition containing no real-time feedback. The self-concordance model, driven by self-determination theory, led to the prediction that a social factor (real-time feedback and faded feedback, in particular) would predict competence and autonomy need satisfaction in trainees. This would enhance trainees' goal self-concordance which would lead to stronger SBT outcomes of higher performance, knowledge acquisition, transfer, and more positive feedback reactions than having no real-time feedback. Results indicated that overall, real-time feedback interventions produced stronger performance outcomes throughout the training period than th (open full item for complete abstract)

Master of Arts, The Ohio State University, 2021, Educational Studies

Phenomenon: In graduate medical education, faculty attending physicians are tasked with training the next generation of physicians, often without formal training in education. Therefore, accrediting bodies require faculty attending physicians to be assessed regularly regarding their teaching practices. This assessment is done via upward feedback from medical trainees, similar to what is commonly known as `student evaluations of teaching.' However, upward feedback in medical education has more facets than student evaluations of teaching, making the process more challenging. It is for this reason that upward feedback in medical education is subpar and poorly utilized. Approach: This report identifies the deficits in the current model of feedback, proposes modifications by utilizing group consensus frameworks, and describes a quantitative pilot study of this novel modification, entitled Teaching Assessment Committee. The Teaching Assessment Committee consists of a group of medical trainees who come together under the leadership of a trained facilitator to generate group-consensus feedback for faculty members in the form of faculty milestones. Hypothesis: The tested hypothesis is that a Teaching Assessment Committee utilized to provide upward feedback to faculty attending physicians is both feasible and preferable to the individuals involved. Findings: This Teaching Assessment Committee was piloted in one large pulmonary and critical care fellowship at a large academic institution in the Midwest, and this group method was found to be both feasible and preferable to the fellows involved compared to established methods of upward feedback obtained via individually-completed electronic forms.

PhD, University of Cincinnati, 2006, Arts and Sciences : Psychology

Although organizations invest significant resources in the development and deployment of 360-degree feedback programs, a limited amount of outcome research has been conducted to explore their effectiveness. Findings from studies investigating the impact of upward and 360-degree feedback interventions on managerial performance are inconsistent. Traditional methods used to assess behavior changes following upward and 360-degree feedback interventions may lead to misleading results because these methods fail to take into account the possibility of different types of change. Golembiewski, Billingsley, and Yeager (1976) developed a typology that delineates the three types of change that may result from organizational development interventions: alpha (actual or true change), beta (change in raters' calibration of rating scale), and gamma change (change in raters' conceptualization of the construct). The present study investigated changes in managerial performance over time through a pre-post study of 360-degree feedback ratings provided at two time points, one-year apart. Participants were 103 managers who were selected to participate in the leadership development program of their employer, a large healthcare organization. Performance changes were explored using both traditional methods (repeated measure analysis of variance and t tests to explore mean ratings differences over time) as well as methods to determine alpha, beta, and gamma change. The present study found that while managers perceived their performance to have improved following a 360-degree feedback and leadership development intervention, the managers' bosses, peers, and subordinates did not report that managerial performance improved overall. Managers' initial performance level, relative to their peers, impacted the magnitude and direction of performance change following the intervention, with low performing managers showing greater rating improvement in comparison to their peers. Different patterns of res (open full item for complete abstract)

Doctor of Philosophy, University of Akron, 2007, Psychology-Industrial/Organizational

Contemporary feedback researchers have adopted theoretical perspectives in which broad personal characteristics interact with the work environment to influence a more narrow, domain-specific trait (i.e., feedback orientation), which in turn, is thought to affect the extent to which individuals engage in the feedback process and feedback seeking. However, to date empirical studies have not examined whether individual difference variables moderate the effects of the feedback environment. In the present study, the organization's feedback environment was thought to interact with trait goal orientation to influence feedback orientation, in turn influencing the extent to which one engages in feedback seeking behavior. In addition, the current study assessed the mediating influence of role clarity on the feedback seeking/ job performance link and the moderating effects of social skill on the feedback seeking/role clarity relationship. While the primary focus of this study was on the model linking the feedback environment to feedback seeking to impact job performance, this study had a secondary purpose; to more closely investigate the link between the multidimensional constructs of the feedback environment and feedback orientation. With the exception of the direct link between feedback seeking and job performance, the results support the proposed model. Perceptions of a supportive feedback environment influence employee feedback orientation, which in turn, positively influence feedback seeking behavior. Furthermore, while feedback seeking directly influenced job performance, role clarity partially mediated this relationship. Moderator analyses indicated that learning goal orientation and performance-avoid goal orientation moderated the feedback environment/feedback orientation link. Results of the facet-level analyses demonstrated that supervisor feedback quality accounted for more variance in utility, accountability, and social awareness than any other feedback environment (open full item for complete abstract)

Doctor of Philosophy, University of Akron, 2024, Psychology-Industrial/Organizational

This dissertation evaluates an intervention designed to improve the Supervisor Feedback Environment (SFE) within the technology department of a Fortune 100 company, emphasizing its critical role in employee development and organizational outcomes. The intervention, grounded in a behavior change framework, enhanced SFE to positively influence employee experience, retention, and performance. The study utilized a comprehensive archival dataset to examine the intervention's impact on SFE and important employee outcomes. The central hypothesis posits that the intervention would significantly enhance SFE, subsequently improving employee performance, retention, and experience. Analytically, the research employed Hierarchical Linear Modeling (HLM) to address the data's nested structure and supplemental non-parametric tests to account for the non-normality of SFE within this dataset. Results supported the intervention's efficacy in improving SFE and demonstrated that enhancing SFE positively affected key employee outcomes. The implications of these findings are discussed, highlighting the necessity of multi-level methods in SFE research and advocating for more synergistic collaboration between academics and practitioners in the field of I/O Psychology. The dissertation underscores the methodological insights gained from the study. It suggests future research directions, mainly focusing on generalizability across different organizational contexts and feedback environments (including co-worker), demographic moderators, and other employee-level variables like feedback orientation play in perceptions of SFE. This research advances the theoretical understanding of SFE and offers practical insights for organizations striving to cultivate more effective feedback climates, cultures, and environments.

Doctor of Philosophy, University of Akron, 2024, Psychology-Industrial/Organizational

Feedback orientation is a person's general receptivity to feedback; although early theorizing about the construct described how it should change over time in the context of ongoing performance management experiences, the extant literature has largely neglected to study whether changes to feedback orientation do in fact occur. This study involves an experiment that was designed to improve participant feedback orientation, and evaluated how that change might be influenced by feedback environment, leader-member exchange, and perceived organizational support. A longitudinal study of feedback orientation was conducted to assess the construct weekly for four weeks, and discontinuous growth curve modeling was used to evaluate whether the experimental intervention induced an increase to feedback orientation that was greater than what would be expected from the normal weekly fluctuations of the construct. Results from an online study of working adults conducted on Prolific revealed that the intervention successfully produced an increase in participants' feedback orientation, relative to both pre-intervention fluctuations and to the impact of a control intervention. Furthermore, initial feedback orientation and leader-member exchange were found to moderate the size of the feedback orientation boost that was produced by the experimental intervention, such that the boost was larger for those with lower initial feedback orientations and for those with higher initial leader-member exchanges. Feedback environment, meanwhile, moderated feedback orientation dynamics such that participants who perceived higher levels of feedback environment maintained higher levels of feedback orientation post-intervention for two weeks after the intervention. These results offer clear insights into feedback orientation dynamics and how they are impacted by critical feedback events, feedback environments, and leader-member exchange.

Doctor of Philosophy, University of Akron, 2020, Psychology-Industrial/Organizational

Research and practitioners have a common interest in the benefits feedback can provide to individuals and employees. Feedback is an important tool that allows individuals to achieve a task, gain more clarity around expectations, and understand their own behavior. Individuals actively engage in feedback seeking to reap such benefits. However, feedback seeking is typically measured in the extant literature as frequency alone, as opposed to using multiple feedback seeking episodes. Additionally, much of the extant literature does not consider the multiple qualitative forms feedback can take. In a recent paper by Gong et al. (2017), a new typology of feedback seeking was developed. This typology includes four different qualitative forms of feedback: self-positive, self-negative, other-positive, and other-negative. Self-positive and self-negative feedback are about the individual receiving feedback, whereas other-positive and other-negative feedback is still given to the recipient but is about others or peers of the recipient performing similar tasks. Gong and colleagues created a scale to measure one's feedback seeking. However, it is a self-report scale about typical behaviors. Thus, the present study determined it is more of a measure of feedback-seeking tendencies. This typology was explored in the context of multiple feedback-seeking episodes and feedback reactions. The present studies examined Gong et al.'s (2017) typology in two different samples. Study 1 consisted of 207 participants from Amazon's Mechanical Turk and Study 2 consisted of 198 participants from a Midwestern University. Results indicated that self-reported feedback-seeking tendencies do not translate into actual feedback-seeking behavior. Additionally, individuals react significantly more favorably to self-positive feedback than all other types of feedback. But, when it came time to actually seek one of the four types of feedback, the majority of individuals in Study 2 sought self-negative fee (open full item for complete abstract)

Doctor of Philosophy, University of Akron, 2020, Psychology-Industrial/Organizational

Researchers and practitioners have a shared interest in better understanding the ways in which job demands ultimately contribute to employee burnout and intentions to turnover. A significant portion of extant research examining these relationships have looked at possible environmental and individual factors that act as buffers, weakening the relationship between demands at work and subsequent negative outcomes. Many of these studies have focused on the personal and contextual variables that minimize the negative impact of job demands on employee psychological need satisfaction specifically. While the feedback environment provided by supervisors has been extensively tied to positive organizational and individual outcomes, to date the supervisor feedback environment has not been examined as a possible buffer between job demands and subsequent negative organizational and individual outcomes. Importantly, the majority of extant feedback environment literature has looked at the ways in which the feedback environment directly reduces or prevents job demands rather than how the feedback environment may be altering existing relationships between job demands and psychological need satisfaction, burnout, or turnover intentions. The current study seeks to explore, for the first time, the ways in which the feedback environment and an individual's receptivity to it may change the negative relationship between job demands and these outcomes. Respondents to an online survey from across industries and job types were used to investigate hypotheses in the present study at multiple time points. Ultimately, results suggest that while the supervisor feedback environment is not lessening or negating the impact of job demands on psychological need satisfaction (and subsequently burnout and turnover intentions), supervisors can still impact employee well-being through the maintenance of a high-quality feedback environment, as employees with strong supervisor feedback environments ar (open full item for complete abstract)

Doctor of Philosophy, University of Akron, 2016, Psychology-Industrial/Organizational

Researchers and practitioners have a shared interest in understanding how to encourage employees to seek out and take opportunities to better themselves. A great deal of extant research has explored the effectiveness of and participation in formal development programs. To that end, previous work has focused on understanding the personal and contextual variables that facilitate interest and motivation in self-development, giving special emphasis to the supportive role supervisors can play by encouraging employees and publicizing opportunities for voluntary development. Consistently, researchers have concluded that participation is influenced directly or indirectly by perceptions that development is needed, and that employees who have firm career goals are more likely to participate. Feedback is one tool supervisors can use to share information critical to effective goal setting and development decision making. The feedback environment provided by supervisors has been tied to positive organizational outcomes that benefit both employee behavior and well-being on the job. Although feedback has been examined extensively in the context of performance management, the value of the feedback environment as a catalyst for self-development has been relatively ignored. The present study examined this relationship and hypothesized the ways in which the supervisor feedback environment relates to self-development. A sample of over 400 respondents to an online survey was used to investigate the questions presented in the present study. Ultimately, results suggest that the supervisor feedback environment meaningfully relates to career insight and to self-development, and that employee's own tendency to seek, appreciate, and use feedback also plays a role in determining whether the supervisor feedback environment and self-development are tied together.

Master of Science, The Ohio State University, 2010, Electrical and Computer Engineering

In this thesis, we have addressed the issue of road congestion due to increased traffic in urban and metropolitan areas and have designed an autonomous longitudinal speed controller as a solution to this problem. One of the best ways to increase efficiency of the available road infrastructure is to enable vehicles to move in a platoon with very small distance headway from the preceding vehicle. We have developed a Longitudinal Finite State Machine which acts as a supervisory control to help the following vehicle to merge behind and follow the preceding vehicle. We have studied the performance of two vehicle following controllers, i.e. LQR based full-state feedback controller and LQR based sequential-state feedback controller, which are enabled and take the control of the vehicle velocity during the “follow” state of the vehicle's Longitudinal FSM. A comparison analysis has been presented between the two controllers which help in reducing the distance headway from the preceding vehicle as well as maintaining string stability within the platoon.

Doctor of Philosophy, The Ohio State University, 2010, EDU Teaching and Learning

Most foreign/second language (L2) teachers invest a significant amount of time and effort in responding to student writing by providing written feedback. Despite the considerable number of experimental studies in the field of L2 writing on effectiveness of written feedback, correction of grammar errors in particular, our understanding of the nature of teacher feedback on student writing or on teachers' attitudes toward providing feedback is limited. The descriptive studies which have been undertaken in the field of L2 written feedback predominantly investigated teacher feedback from student perspectives. Therefore, little is known about the perceptions of L2 teachers on written feedback. Since most studies on the topic have been conducted in the English as a second language context, studies conducted in foreign language contexts are rare. Recently, research in the field of L2 writing has increasingly acknowledged the influence of contextual factors on teacher feedback, in turn creating a need for comparative studies on written feedback involving multiple populations with different linguistic/cultural backgrounds in diverse settings to fill a gap in the current research base. This comparative study explored teacher feedback on college L2 student writing from the teacher perspective by investigating the similarities and differences in perceptions of written feedback between teachers of a foreign language (Korean) and teachers of a second language (ESL) in North America. Using an online survey, the study investigated the perceptions of a total of 153 college instructors of ESL and of KFL (Korean as a foreign language) across North America. The 46-item questionnaire inquired about perceived types of written feedback, perceptions of the use of written feedback, perceptions of selected approaches to responding to student writing, and perceived written feedback practices. Descriptive and correlational statistics were used for the data analysis. Major differences between (open full item for complete abstract)

Doctor of Philosophy, University of Akron, 2006, Psychology-Industrial/Organizational

Feedback orientation, a construct proposed by London and Smither (2002), is an individual's overall receptivity to feedback. The current research developed and validated a multidimensional measure of feedback orientation. Exploratory and confirmatory factor analyses found support for four dimensions: utility, accountability, social awareness, and feedback self-efficacy. Substantial support was also found for the reliability and validity of each of these dimensions across two distinct samples. This new instrument, the Feedback Orientation Scale (FOS), is a valuable tool for researchers and practitioners to better understand individual differences in the feedback process.

Master of Science, Miami University, 2024, Mechanical and Manufacturing Engineering

The study of human balance postural mechanics remains a subject of considerable interest, given its significance in understanding modes of instability leading to falls in individuals, especially for balance impairments due to neuromuscular and musculoskeletal disorders. Understanding the mechanism of instability can positively impact the quality of life of billions of people around the world, viz., minimization and mitigation of fall risk and aiding rehabilitation. Studies have shown, theoretically, that modes of instability due to excessive neuromuscular feedback gain and delay give rise to instability in the form of limit cycle oscillations. In this thesis, we delve into the realms of upright human balance and understand instability mechanisms by inducing neuromuscular feedback delay through virtual reality (VR). Using VR for feedback manipulation, we analyzed the center of pressure data of healthy participants across multiple age groups during quiet standing to identify the signs of impaired balance based on the occurrence of limit cycle oscillations throughout the experiment. This thesis aims to experimentally verify that instability caused by excessive neuromuscular feedback delay results in instability due to LCO and to understand the compensatory behavior of human balance control after exposure to sustained time delay, which may be used for future balance studies.

Doctor of Philosophy, The Ohio State University, 2024, Astronomy

We present a statistical analysis of the local environments, approximately 50-150 pc scale, of recent (125 years) supernovae (SNe) in nearby spiral galaxies. To do this, we identify 63 SNe observed during the years 1901-2023 that lie within the area covered by recent multi-wavelength high physical resolution surveys. We measure the molecular gas environment using 1'' (150 pc) resolution CO(2-1) maps obtained using the Atacama Large Millimeter/submillimeter Array. This is arguably the first such study to approach the scales of individual massive molecular clouds. We detect CO(2-1) emission near 60% of the sample at 150pc resolution, compared to 35% of map pixels with CO(2-1) emission, and up to 95% of the SNe at 1kpc resolution compared to 80% of map pixels with CO(2-1) emission. We expect that many of the SNe coincident with CO(2-1) emission may eventually interact with nearby molecular clouds. This is consistent with the observation of widespread SN-molecular gas interaction in the Milky Way. The other 40% of SNe without strong CO(2-1) detections will deposit their energy in the diffuse interstellar medium (ISM), perhaps helping drive large-scale turbulence or galactic outflows. Broken down by type, we detect CO(2-1) emission at the sites of 85% of our 9 stripped-envelope SNe (SESNe), 40% of our 34 Type II SNe, and 35% of our 13 Type Ia SNe. Consistent with their hypothesized origin from very short-lived massive stars, SESNe are most closely associated with the brightest CO(2-1) emitting regions in our sample. We also measure the H-alpha emission, a tracer of the presence of massive stars and ionized gas, at the sites of 33 of the sample SNe in 10 galaxies that have been covered by wide-area optical spectroscopic mapping using the MUSE instrument on the Very Large Telescope. We find that 41% (13/32) of these SNe occur coincident with a previously identified HII region. For comparison, HII regions cover 32% of the area within 1 kpc of any recent SN. Contrasting thi (open full item for complete abstract)

Master of Science, Miami University, 2023, Mechanical Engineering

Available devices with smaller touchscreen displays (TSDs) offer users adequate haptic feedback, whereas larger TSDs still lack meaningful tactile sensations. This study is focused on rendering vibrotactile feedback on large TSDs. Existing methods for localized vibrotactile rendering on large TSDs use many actuators. Practically, using many actuators is not desirable due to space constraints, power supply limitations, etc., for consumer-centric large TSD devices. Therefore, this study investigates localized vibrotactile feedback on large TSDs using a restricted number of electrostatic resonant actuators (ERAs). Using flexible boundary conditions combined with multi-frequency excitation, a novel method is presented to render localized vibrotactile feedback for two types of large TSDs: a narrow touch bar and a rectangular touch surface. A method for managing/positioning localized haptic feedback on large TSDs is also investigated. In-house finite-element-based simulation models of TSDs are developed along with experimental prototypes for verifying the vibrotactile performance. The modeling and analysis strategy presented here is general and can be extended for haptic rendering methods of different touch surfaces, actuators, and boundary conditions. Finally, model-based parametric studies are presented for better design considerations and improved vibrotactile intensity.

Master of Science in Electrical Engineering (MSEE), Wright State University, 2023, Electrical Engineering

Stochastic resonance (SR) is a phenomenon that can enhance the detection or transmission of weak signals by adding random noise to a non-linear system. SR introduced into the human motor control system as a subthreshold mechanical vibration has shown promise to improve sensitivity to haptic feedback. SR can be valuable in a laparoscopic surgery application, where haptic feedback is critical. This research sought to find if applying SR to the human motor control system improves performance in a laparoscopic probing task, if the performance differs based on the location of stochastic resonance application, and if there are sustained effects from SR after its removal. Subjects were asked to perform a palpation task using a laparoscopic probe to determine whether a series of simulated tissue samples contained a tumor. Subjects in the treatment groups were presented with a series of samples under the following conditions: Pre-SR, SR applied to the forearm or elbow, and Post-SR. Subjects in the control group did not have SR applied at any point. Performance was measured through the accuracy of tissue assessment, subjects' confidence in their assessment, and assessment time. Data from 27 subjects were analyzed to investigate the application of stochastic resonance and its sustained effects to improve haptic feedback sensitivity in a simulated laparoscopic task. The forearm group was shown to have significant improvement in the accuracy of tissue identification and sensitivity to haptic feedback with the application of SR. Additionally, the forearm group showed a greater improvement in accuracy and sensitivity than the elbow group. Finally, after SR was removed, the forearm group showed sustained significant improvement in accuracy and sensitivity. Therefore, the experiment results supported the hypotheses that stochastic resonance improves subjects' performance and haptic perception, that performance improvement differs based on application location, and that subjec (open full item for complete abstract)

Bachelor of Business Administration (BBA), Ohio University, 2023, Business Administration

Feedback is worthless if it is ineffective in creating a positive change. Research has proven that the source and frequency of feedback are some of the many characteristics that companies can alter to create effective feedback. Our study utilized a survey to discover which elements of feedback companies can manipulate to increase their employees' motivation to change and extend this body of research by examining how platform and type of feedback affect motivation to change. Perceived competency, fairness, and responsibility were also measured to determine whether they had a mediating effect on the variables. The results suggest that quantitative and in-person feedback led to increased motivation to change, with perceived competency and perceived responsibility as significant mediating variables. This study contributes to both research and practice by exploring various ways to manipulate negative feedback to make it more effective for employees.

Master of Arts (MA), Bowling Green State University, 0, Psychology/Industrial-Organizational

Feedback has long been proposed to impact task performance, however limited work has explored characteristics of feedback beyond valence. The present study proposed that feedback context, namely if feedback is provided in public or private contexts, also plays a role in affecting task performance outcomes. This research explored the indirect, interactive effects of feedback context and valence on task performance via the adoption of goal orientations. Through an experimental design, I investigated how manipulated feedback characteristics influence the adoption of learning, performance-approach, and performance-avoid goal orientations, which in turn affect rates of task performance. Findings suggest that neither feedback valence nor feedback context significantly relate to goal orientation adoption or task performance. Results of this study did not support relationships that are widely suggested in the literature between goal orientations and task performance, raising some question about how suitable the method or sample was to the subject matter. Nevertheless, feedback context remains a largely neglected area of exploration and opportunity exists for better understanding of contextual factors that may influence feedback effects on performance.

PHD, Kent State University, 2022, College of Education, Health and Human Services / School of Lifespan Development and Educational Sciences

The purpose of this study was to explore the effectiveness of a tennis serve intervention on motor skill performance and motor skill procedural knowledge of novice middle school student-athletes who were unprepared for interscholastic competition. The intervention package introduced mobile device technology within Mosston and Ashworth's (2002) reciprocal style to implement digital task cards with a video model and three feedback conditions: peer feedback using criteria information, peer-assisted video feedback, and peer-assisted video feedback with criteria information. Results from three single-case experiments showed that the intervention improved performance during practice and produced positive learning outcomes for all six participants. Social validity interviews showed satisfaction with the amount of feedback provided within the reciprocal style, an understanding of the importance of using the proper procedure for the tennis serve, and performance change significant enough for inter-scholastic competition. Implications for research included a need for more specific standards for treatment integrity and the possible restructuring of the experimental design to obtain valid results from an intervention focused on peer-assisted video feedback with criteria information throughout instruction. Implications for practice included ways to incorporate mobile device technology for teaching the tennis serve, focus on knowledge of performance over knowledge of results feedback for procedural knowledge acquisition, and gather information to continuously improve instruction.