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Time has always had a special status in physics because of its fundamental role in specifying the regularities of nature and because of the extraordinary precision with which it can be measured. This precision enables tests of fundamental physics and cosmology, as well as practical applications such as satellite navigation. Recently, a regime of operation for atomic clocks based on optical transitions has become possible, promising even higher performance. We report the frequency ratio of two optical atomic clocks with a fractional uncertainty of 5.2 × 10-17. The ratio of aluminum and mercury single-ion optical clock frequencies VAL+/VHg+ is 1.052871833148990438(55), where the uncertainty comprises a statistical measurement uncertainty of 4.3 × 10-17, and systematic uncertainties of 1.9 × 10-17 and 2.3 × 10-17 in the mercury and aluminum frequency standards, respectively. Repeated measurements during the past year yield a preliminary constraint on the temporal variation of the fine-structure constant α of α/α = (-1.6 ± 2.3) × 10-17/year. [ABSTRACT FROM AUTHOR]

Objective:The study aimed to explore contemporary collaborative experiences of nurse practitioners (NPs) in providing care with general practitioners (GPs) and allied health care professionals.Design:A qualitative descriptive, exploratory design was considered the most appropriate to achieve the study objectives. This allowed the researcher at first hand to gain a thorough understanding of the nurse participants' experiences.Setting:The study was conducted in urban, rural and remote clinics and hospitals throughout New South Wales, Australia, where the NPs were authorised to care for the community.Participants:Nine authorised NPs were the key participants in the study.Results:Analysis identified one main theme of Collaboration and three sub themes that were named as Total Collaboration, Partial Collaboration and Non Collaboration.Conclusion:In this study, most NPs reported dissatisfaction from working in ineffective collaborative relationships with medical and allied health care professionals. Total collaboration did not automatically occur and was identified as the exception. Sustainable collaborative partnerships should be developed with all heath care providers by acknowledging each others unique, valuable contribution. Despite this challenging and complex situation, NSW NPs remained determined to provide advanced nursing care for patients and to establish and maintain effective collaboration with all health care professionals. [ABSTRACT FROM AUTHOR]

This case study examines the adaptation of an existing online, asynchronous faculty development resource at the University of New Mexico to support the unanticipated need for all instructors to teach remotely starting in spring 2020, due to the COVID-19 pandemic. The course-entitled Evidence-Based Practices for Teaching Online (EBPTO)-was previously utilized to support instructor transitions to distance education by applying constructivist principles to the development of evidence-based online teaching practices. The course was adapted to address institutional and instructor needs as a result of the pandemic, including increasing facilitation resources. The largest EBPTO cohort, with 117 participants, began in June 2020. Data were collected through a reflective journal administered at the mid-point and an end-of-course survey. Analysis of the reflective journal provided insight into participants' learning experience in terms of key "takeaways," LMS tools that they had the opportunity to practice, and "lingering questions" that they had. The top 3 takeaways were the usefulness of course mapping, the usefulness of backwards design, and the deepening familiarity with LMS tools. Results from the end-of-course survey showed positive feedback from participants regarding perceived achievement of the course learning objectives, even after scaling the course to accommodate the large number of instructors moving to remote instruction., (© The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature 2022.)

Moral vitalism refers to a tendency to view good and evil as actual forces that can influence people and events. The Moral Vitalism Scale had been designed to assess moral vitalism in a brief survey form. Previous studies established the reliability and validity of the scale in US-American and Australian samples. In this study, the cross-cultural comparability of the scale was tested across 28 different cultural groups worldwide through measurement invariance tests. A series of exact invariance tests marginally supported partial metric invariance, however, an approximate invariance approach provided evidence of partial scalar invariance for a 5-item measure. The established level of measurement invariance allows for comparisons of latent means across cultures. We conclude that the brief measure of moral vitalism is invariant across 28 cultures and can be used to estimate levels of moral vitalism with the same precision across very different cultural settings., Competing Interests: One of the authors, José Luis Castellanos Guevara was affiliated with a commercial institution “ConSol” and received support in the form of salary from “ConSol”. This does not alter our adherence to PLOS ONE policies on sharing data and materials. There are no patents, products in development or marketed products associated with this research to declare.

We present the design and performance of a low-cost, reciprocal, compact free-space terminal employing tip/tilt pointing compensation that enables optical two-way time-frequency transfer over free-space links across the turbulent atmosphere. The insertion loss of the terminals is ∼1.5  dB with total link losses of 15 dB, 24 dB, and 50 dB across horizontal, turbulent 2-km, 4-km, and 12-km links, respectively. The effects of turbulence on pointing control and aperture size, and their influence on the terminal design, are discussed.

Dual-comb spectroscopy is an emerging new spectroscopic tool that exploits the frequency resolution, frequency accuracy, broad bandwidth, and brightness of frequency combs for ultrahigh-resolution, high-sensitivity broadband spectroscopy. By using two coherent frequency combs, dual-comb spectroscopy allows a sample's spectral response to be measured on a comb tooth-by-tooth basis rapidly and without the size constraints or instrument response limitations of conventional spectrometers. This review describes dual-comb spectroscopy and summarizes the current state of the art. As frequency comb technology progresses, dual-comb spectroscopy will continue to mature and could surpass conventional broadband spectroscopy for a wide range of laboratory and field applications.

We describe the design, fabrication, and performance of a self-referenced, optically coherent frequency comb. The system robustness is derived from a combination of an optics package based on polarization-maintaining fiber, saturable absorbers for mode-locking, high signal-to-noise ratio (SNR) detection of the control signals, and digital feedback control for frequency stabilization. The output is phase-coherent over a 1-2 μm octave-spanning spectrum with a pulse repetition rate of ∼200 MHz and a residual pulse-to-pulse timing jitter <3 fs well within the requirements of most frequency-comb applications. Digital control enables phase coherent operation for over 90 h, critical for phase-sensitive applications such as timekeeping. We show that this phase-slip free operation follows the fundamental limit set by the SNR of the control signals. Performance metrics from three nearly identical combs are presented. This laptop-sized comb should enable a wide-range of applications beyond the laboratory.

Non-contact surface mapping at a distance is interesting in diverse applications including industrial metrology, manufacturing, forensics, and artifact documentation and preservation. Frequency modulated continuous wave (FMCW) laser detection and ranging (LADAR) is a promising approach since it offers shot-noise limited precision/accuracy, high resolution and high sensitivity. We demonstrate a scanning imaging system based on a frequency-comb calibrated FMCW LADAR and real-time digital signal processing. This system can obtain three-dimensional images of a diffusely scattering surface at stand-off distances up to 10.5 m with sub-micrometer accuracy and with a precision below 10 µm, limited by fundamental speckle noise. Because of its shot-noise limited sensitivity, this comb-calibrated FMCW LADAR has a large dynamic range, which enables precise mapping of scenes with vastly differing reflectivities such as metal, dirt or vegetation. The current system is implemented with fiber-optic components, but the basic system architecture is compatible with future optically integrated, on-chip systems.

We demonstrate a self-referenced fiber frequency comb that can operate outside the well-controlled optical laboratory. The frequency comb has residual optical linewidths of < 1 Hz, sub-radian residual optical phase noise, and residual pulse-to-pulse timing jitter of 2.4 - 5 fs, when locked to an optical reference. This fully phase-locked frequency comb has been successfully operated in a moving vehicle with 0.5 g peak accelerations and on a shaker table with a sustained 0.5 g rms integrated acceleration, while retaining its optical coherence and 5-fs-level timing jitter. This frequency comb should enable metrological measurements outside the laboratory with the precision and accuracy that are the hallmarks of comb-based systems.

We demonstrate a dual-comb spectrometer using stabilized frequency combs spanning 177 to 220 THz (1360 to 1690 nm) in the near infrared. Comb-tooth-resolved measurements of amplitude and phase generate over 4×10(5) individually resolved spectral elements at 100 MHz point spacing and kilohertz-level resolution and accuracy. The signal-to-noise ratio is 100 to 3000 per comb tooth. Doppler-broadened phase and amplitude spectra of CO(2), CH(4), C(2)H(2), and H(2)O in a 30 m multipass cell agree with established spectral parameters, achieving high-resolution measurements with optical bandwidth generally associated with blackbody sources.

Coherent dual comb spectroscopy can provide high-resolution, high-accuracy measurements of a sample response in both magnitude and phase. We discuss the achievable signal-to-noise ratio (SNR) due to both additive white noise and multiplicative noise, and the corresponding sensitivity limit for trace gas detection. We show that sequential acquisition of the overall spectrum through a tunable filter, or parallel acquisition of the overall spectrum through a detector array, can significantly improve the SNR under some circumstances. We identify a useful figure of merit as the quality factor, equal to the product of the SNR, normalized by the square root of the acquisition time, and the number of resolved frequency elements. For a single detector and fiber-laser based system, this quality factor is 10(6) - 10(7) Hz(1/2).

Linear optical sampling characterizes a sample by measuring the distortions on a transmitted optical field, thereby quantifying the sample's optical response. By exploiting the high mutual coherence between two phase-locked femtosecond fiber lasers, we achieve very high signal-to-noise ratio measurements of transmitted optical electric fields through coherent averaging. We measure the optical electric fields with 15.16 bits of dynamic range (91 dB in intensity) and with 525 fs timing resolution over a 10 ns time window, in a 5.1 s averaging period.

Time has always had a special status in physics because of its fundamental role in specifying the regularities of nature and because of the extraordinary precision with which it can be measured. This precision enables tests of fundamental physics and cosmology, as well as practical applications such as satellite navigation. Recently, a regime of operation for atomic clocks based on optical transitions has become possible, promising even higher performance. We report the frequency ratio of two optical atomic clocks with a fractional uncertainty of 5.2 x 10(-17). The ratio of aluminum and mercury single-ion optical clock frequencies nuAl+/nuHg+ is 1.052871833148990438(55), where the uncertainty comprises a statistical measurement uncertainty of 4.3 x 10(-17), and systematic uncertainties of 1.9 x 10(-17) and 2.3 x 10(-17) in the mercury and aluminum frequency standards, respectively. Repeated measurements during the past year yield a preliminary constraint on the temporal variation of the fine-structure constant alpha of alpha/alpha = (-1.6+/-2.3) x 10(-17)/year.

We demonstrate a fundamentally mode-locked fiber laser with a repetition frequency in excess of 2 GHz at a central wavelength of 1.535 mum. Co-doped ytterbium-erbium fiber provides the gain medium for the laser, affording high gain per unit length, while a semiconductor saturable absorber mirror (SAM) provides the pulse shaping mechanism in a standing wave cavity. Results are shown confirming cw mode-locking for 1 GHz and 2 GHz repetition frequency systems. The response of the frequency comb output to pump power variations is shown to follow a single pole response. The timing jitter of a 540MHz repetition-rate laser has been suppressed to below 100 fs through phase-lead compensated feedback to the pump power. Alternatively, a single comb line of a 850MHz repetition-rate laser has been phase-locked to a narrow linewidth cw laser with an in-loop phase jitter of 0.06 rad(2). The laser design is compatible with low-noise oscillator applications.

The frequency comb from a mode-locked fiber laser can be stabilized through feedback to the pump power. An understanding of the mechanisms and bandwidth governing this feedback is of practical importance for frequency comb design and of basic interest since it provides insight into the rich nonlinear laser dynamics. We compare experimental measurements of the response of a fiber-laser frequency comb to theory. The laser response to a pump-power change follows that of a simple low-pass filter with a time constant set by the gain relaxation time and the system-dependent nonlinear loss. Five different effects contribute to the magnitude of the response of the frequency comb spacing and offset frequency but the dominant effects are from the resonant contribution to the group velocity and intensity-dependent spectral shifts. The origins of the intensity-dependent spectral shifts are explained in terms of the laser parameters.

A frequency comb is generated with a chromium-doped forsterite femtosecond laser, spectrally broadened in a dispersion-shifted highly nonlinear fiber, and stabilized. The resultant evenly spaced comb of frequencies ranges from 1.1 to beyond 1.8 microm. The frequency comb was referenced simultaneously to the National Institute of Standards and Technology's optical frequency standard based on neutral calcium and to a hydrogen maser that is calibrated by a cesium atomic fountain clock. With this comb we measured two frequency references in the telecommunications band: one half of the frequency of the d/f crossover transition in 87Rb at 780 nm, and the methane v2 + 2v3 R(8) line at 1315 nm.

The Brief Loquaciousness and Interpersonal Responsiveness Test (BLIRT) measures the extent to which people respond to others quickly and effusively. The BLIRT displays desirable psychometric properties and distinguishes people who should theoretically score high (e.g., car salespersons) from those who should score low (e.g., librarians). Scores on the scale predict (a) the amount and rapidity of people's verbal responses in an unstructured interaction, (b) how likable and competent people's classmates perceive them to be early in the semester, (c) how quickly people respond to an obnoxious cell-phone user and how physiologically aroused they become, and (d) how quickly and emphatically people respond to a series of personal insults as well as their degree of physiological arousal. Converging evidence indicates that blirtatiousness is unique in its ability to amplify people's qualities, making these qualities more readily observable to perceivers.

Recent interest in the implicit self-esteem construct has led to the creation and use of several new assessment tools whose psychometric properties have not been fully explored. In this article, the authors investigated the reliability and validity of seven implicit self-esteem measures. The different implicit measures did not correlate with each other, and they correlated only weakly with measures of explicit self-esteem. Only some of the implicit measures demonstrated good test-retest reliabilities, and overall, the implicit measures were limited in their ability to predict our criterion variables. Finally, there was some evidence that implicit self-esteem measures are sensitive to context. The implications of these findings for the future of implicit self-esteem research are discussed.

A prospective study of 423 MBA students examined the interplay of identity negotiation and group functioning. The findings revealed that self-verification effects (through which group members brought others to see them as they saw themselves) heightened participants' feelings of connection to their groups (i.e., more identification and social integration and less emotional conflict) and improved group project grades on creative tasks (tasks that benefit from divergent perspectives). Appraisal effects (through which groups brought members to see themselves as the group saw them) facilitated group project grades on computational tasks (tasks that require deriving one correct answer). In addition, self-verification effects were more prevalent than appraisal effects. The authors discuss the implications of these findings for understanding the links among self-verification, self-categorization, and group outcomes.

When spouses received feedback that disconfirmed their impressions of their partners, they attempted to undermine that feedback during subsequent interactions with these partners. Such partner verification activities occurred whether partners construed the feedback as overly favorable or overly unfavorable. Furthermore, because spouses tended to see their partners as their partners saw themselves, their efforts to restore their impressions of partners often worked hand-in-hand with partners' efforts to verify their own views. Finally, support for self-verification theory emerged in that participants were more intimate with spouses who verified their self-views, whether their self-views happened to be positive or negative.

A cross-sectional study of dating partners and a longitudinal study of college roommates revealed that the confidence and accuracy of their impressions were often dissociated. For example, relationship length and degree of involvement tended to increase the confidence of people's impressions, but neither variable consistently increased the accuracy of their impressions of their partners' sexual histories, activity preferences, and so on. A third study showed that relationship length and involvement increased the richness of impressions, and richness fostered confidence. The authors conclude that although confidence-accuracy dissociations are surely problematic in some instances, their apparent pervasiveness raises the possibility that confidence may sometimes contribute to relationship quality even when it is unrelated to accuracy.

Do clinically depressed individuals seek favorable or unfavorable information about the self? Self-verification theory makes the counterintuitive prediction that depressed individuals solicit feedback that confirms their negative self-views. To test this prediction, participants were classified on the basis of a structured clinical interview and self-report measures into high-esteem, low self-esteem, and depressed groups. All participants were offered a choice between receiving favorable or unfavorable feedback; 82% of the depressed participants chose the unfavorable feedback, compared to 64% of the low self-esteem participants and 25% of the high self-esteem participants. Additional evidence indicated that depressed individuals also failed to exploit fully an opportunity to acquire favorable evaluations that were self-verifying. The authors discuss how seeking negative evaluations and failing to seek favorable evaluations may help maintain depression.

Three studies were conducted to validate the conceptualization of global self-esteem as consisting of two dimensions: a sense of social worth, or self-liking, and a sense of personal efficacy, or self-competence. In Study 1, confirmatory factor analysis was used to test the a priori structure of the Self-Liking/Self-Competence Scale, a self-report instrument designed to measure the two dimensions. In Study 2, a second structural analysis showed the dimensionality of Rosenberg's (1965) Self-Esteem Scale to parallel the proposed dichotomy. In Study 3, self-liking and self-competence were related to several theoretically linked constructs--depression, self-perceived abilities, and perceived parental approval--with the resulting pattern of correlations supporting their conceptualization as substantively distinct dimensions. The implications of these findings for understanding global self-esteem are discussed.

The authors report two longitudinal studies of new college roommates (Ns = 69 and 95 pairs). In both studies, targets' initial self-views predicted changes in perceivers' appraisals of them, and perceivers' initial appraisals predicted changes in targets' self-views, although few dyads displayed both effects. The perceiver-driven and target-driven effects occurred when appraisals and self-views were negative as well as positive. Implications for self-verification theory and symbolic interactionism are discussed, and a less restrictive model of how appraisals influence self-views is proposed.

We proposed that married persons would want their spouses to see them as they saw themselves but that dating persons would want their relationship partners to evaluate them favorably. A survey of 176 married and dating couples tested these predictions. Just as married persons were most intimate with spouses whose evaluations verified their self-views, dating persons were most intimate with partners who evaluated them favorably. For married people with negative self-views, then, intimacy increased as their spouses evaluated them more negatively. Marriage apparently precipitates a shift from a desire for positive evaluations to a desire for self-verifying evaluations.

Whereas earlier research suggests that the fruits of introspection may promote error and misperception, this research suggests that thinking about the self may sometimes foster self-insight. Participants who had opportunity to reflect on themselves were particularly inclined to display self-insight by (a) rating feedback that confirmed their self-views as self-descriptive (Experiments 1 and 3), (b) rating themselves in ways that matched their friends' appraisals of them (Experiment 2), and (c) choosing a self-verifying interaction partner rather than an overly favorable one (Experiment 4). These effects were moderated by the nature of the introspective activity (Experiment 3) and by its duration (Experiment 4). Implications of these findings for the nature of self-knowledge and the worlds people construct around themselves are discussed.

We propose that people with negative self-views are rejected because they gravitate to partners who view them unfavorably. In relation to nondepressed college students (n = 28), depressives (n = 13) preferred interaction partners who evaluated them unfavorably (Study 1). Similarly, in relation to nondepressives (n = 106), depressives (n = 10) preferred friends or dating partners who evaluated them unfavorably (Study 2). Dysphorics (n = 6) were more inclined to seek unfavorable feedback from their roommates than were nondepressives (n = 16); feedback-seeking activities of dysphorics were also associated with later rejection (Study 3). Finally, people with negative self-views (n = 37) preferentially solicited unfavorable feedback, although receiving such feedback made them unhappy, in comparison with people with positive self-views (n = 42; Study 4). It seems a desire for self-verification compels people with negative self-views to seek unfavorable appraisals.

Swann, Wenzlaff, Krull, and Pelham (1992) suggested that depressed and dysphoric persons verify their self-conceptions by seeking rather negative appraisals. Hooley and Richters (1992) and Alloy and Lipman (1992) have worried that (a) idiosyncratic features of Swann et al.'s participants and design may have produced their effects and (b) Swann et al. presented no evidence that self-verification strivings are motivated. We address these issues empirically. Study 1 showed that 20 dysphoric participants preferred interacting with a person who appraised them unfavorably over participating in another study, in comparison with 30 nondysphorics. Study 2 revealed that 26 dysphoric persons responded to feedback that challenged their negative self-view by working to reaffirm their low self-esteem, in comparison with 47 nondysphorics. These findings support the notion that at some level depressed and dysphoric persons want rather negative appraisals.

Although people with negative self-views want to be liked at some level, they repeatedly enact behaviors that alienate their relationship partners. Why? One possibility is that such persons reside in social environments that offer them little insight into what they are doing wrong. Although persons who had negative self-views elicited unfavorable reactions, they did not appreciate this fact because their interaction partners concealed their aversion behind a facade of kind words. To be sure, the interaction partners of people with negative self-views tended to leak their disdain nonverbally. These negative nonverbal messages proved to be uninformative, however, because people with negative self-views overlooked them. These data imply that people with negative self-views may live in social worlds in which they are deprived of corrective feedback that could allow them to improve themselves.

Why do people choose interaction partners who see them as they see themselves? Self-verification theorists propose that a desire to bolster perceptions of predictability and control underlies such activities. In contrast, advocates of positivity strivings argue that people choose such interaction partners in the hope of making themselves feel good. Two studies tested these competing explanations by examining the spontaneous verbalizations of participants as they chose interaction partners. The results suggested that positivity as well as self-verification strivings caused participants with positive self-views to choose partners who appraised them favorably. The epistemic considerations underlying self-verification processes, however, best explained why people with negative self-views chose partners who appraised them unfavorably.

We describe a general approach for the quantitative analysis of the interaction among fluorescent peptide ligands (L), receptors (R), and G proteins (G) using fluorescence flow cytometry. The scheme depends upon the use of commercially available fluorescent microbeads as standards to calibrate the concentration of fluorescent peptides in solution and the receptor number on cells in suspension. We have characterized a family of fluoresceinated formyl peptides and analyzed both steady-state and dynamic aspects of ligand formyl peptide-receptor interactions in digitonin-permeabilized human neutrophils. Detailed receptor-binding studies were performed with the pentapeptide N-formyl-Met-Leu-Phe-Phe-Lys-fluorescein. Equilibrium studies showed that GTP [S] caused a loss of binding affinity of approximately two orders of magnitude, from approximately 0.04 nM (LRG) to approximately 3 nM (LR), respectively. Kinetic studies revealed that this change in affinity was principally due to an increase in the dissociation rate constants from approximately 1 x 10(-3) s-1 (LRG) to approximately 1 x 10(-1) s-1 (LR). In contrast, the association rate constants in the presence and absence of guanine nucleotide (approximately 3 x 10(7) s-1 M-1) were statistically indistinguishable and close to the diffusion limit. In the presence of guanine nucleotide (LR), the kinetic data were adequately fit by a single-step reversible-binding model. In the absence of guanine nucleotides, not all receptors have rapid access to G to form the LRG ternary complex. Mathematically, those R that have rapid access to G are either precoupled to R or the association of G with R is fast compared to the association of L with R. The physiological consequences of coupling heterogeneity are discussed.

We propose that a preference for favorable social feedback (i.e., self-enhancement) requires only that feedback be characterized as favorable or unfavorable but that a preference for self-confirming feedback (i.e., self-verification) is based on a more elaborate set of cognitive operations that requires both the characterization of feedback and a subsequent comparison of that feedback to a representation of self stored in memory. Study 1 set the stage for testing this hypothesis by showing that depriving people of processing resources interfered with their tendency to access their self-conceptions. In Studies 2 and 3, participants who were deprived of resources preferred the favorable, self-enhancing evaluator, whereas control participants displayed a preference for the self-verifying evaluator, even if that evaluator was relatively unfavorable.

Intact neutrophils appear to exhibit interconverting formyl peptide receptor states. The first may be active in transduction and has a dissociation half-time of less than 10 sec. The second appears to be inactive and has a dissociation half-time of approximately 2 min. Neutrophil signals and responses are transient following "pulse" stimulation (when the stimulus is presented and then rapidly removed). The responses decay to baseline following a latency period comparable to the lifetime of the activated receptor. These results are consistent with the notion of transient interconverting receptor states and are discussed in terms of the biochemistry and amplification of the cell activation pathways. We examined the effect of guanine nucleotides on ligand-receptor dynamics at 37 degrees C in neutrophils permeabilized with digitonin, using continuous fluorometric measurements. The permeabilized cells exhibit a single class of slowly-dissociating receptor with a half-time similar to the inactive state. When guanine nucleotide is added, the receptors dissociate with a half-time similar to the first state. The effect of guanine nucleotide is inhibited by Ca++ concentrations above 10 microM. When receptors in permeabilized cells are ADP-ribosylated in the presence of pertussis toxin, the rapidly dissociating state is detected. These results suggest that the dynamics of ligand-receptor interaction under physiological conditions are controlled by a pertussis-toxin-sensitive guanine-nucleotide-binding protein. Guanine nucleotide regulates interconverting states of the formyl peptide receptor and mimics the dynamic states of the receptor observed in the intact cell during stimulation. A model which accounts for these data is described.

Past research has shown that conventional strategies of persuasion tend to be ineffective against people who are highly certain of their beliefs. To change the beliefs of such individuals, we devised a paradoxical strategy that consisted of posing superattitudinal leading questions (questions that encouraged respondents to make statements that were consistent with, but more extreme than, their own viewpoints). We expected that individuals who were high in belief certainty would resist such questions and, therefore, change their beliefs in the opposite direction. To test this reasoning, we used either a conventional or a paradoxical strategy to change people's beliefs about women's roles. As suggested by earlier research, the conventional strategy was effective in changing the beliefs of targets who were low in belief certainty only. In contrast, the paradoxical strategy was effective in changing the beliefs of targets who were high in belief certainty only. A follow-up investigation replicated this effect and indicated that paradoxical injunctions change people's positions on belief dimensions rather than their perception of the dimension itself. The implications of these findings for an understanding of the interpersonal mechanisms that generate stability and change in people's beliefs are discussed.

When a perceiver forms an expectancy about a target individual that is discrepant with that target's self-conception, whose viewpoint will triumph? Although research on behavioral confirmation argues that perceivers will "win" by causing targets to confirm the expectancy, research on self-verification argues that targets will "win" by bringing perceivers to treat them in a manner that confirms their self-conceptions. The research reported here sought to reconcile these competing viewpoints by considering the certainty of perceivers' expectancies and targets' self-conceptions. Perceivers first formed relatively certain or uncertain expectancies about targets that were inconsistent with targets' self-conceptions. They then interacted with targets, who possessed relatively certain or uncertain self-conceptions, in a series of three successive interview sessions. Analyses of the behavior or targets indicated that self-verification always occurred when targets were certain of their self-conceptions. Self-verification also tended to occur when both perceivers and targets were uncertain of their beliefs. Behavioral confirmation tended to occur only when perceivers were certain of their expectancies and targets were uncertain of their self-conceptions. At the end of the experiment, perceivers had generally abandoned their expectancies, but targets revealed no self-rating change. The conditions under which self-verification versus behavioral confirmation occur are discussed.

Three factors were identified that uniquely contribute to people's global self-esteem: (a) people's tendencies to experience positive and negative affective states, (b) people's specific self-views (i.e., their conceptions of their strengths and weaknesses), and (c) the way people frame their self-views. Framing factors included the relative certainty and importance of people's positive versus negative self-views and the discrepancy between people's actual and ideal self-views. The contribution of importance to people's self-esteem, however, was qualified in 2 ways. First, importance contributed only to the self-esteem of those who perceived that they had relatively few talents. Second, individuals who saw their positive self-views as important were especially likely to be high in self-esteem when they were also highly certain of these positive self-views. The theoretical and therapeutic implications of these findings are discussed.

Whole cells of Escherichia coli containing aspartase activity were immobilized by mixing a cell suspension with a liquid isocyanate-capped polyurethane prepolymer (Hypol). The immobilized cell preparation was used to convert ammonium fumarate to l-aspartic acid. Properties of the immobilized E. coli cells containing aspartase were investigated with a batch reactor. A 1.67-fold increase in the l-aspartic acid production rate was observed at 37 degrees C as compared to 25 degrees C operating temperature. The pH optimum was broad, ranging from 8.5 to 9.2. Increasing the concentration of ammonium fumarate to 1.5 M from 1.0 M negatively affected the reaction rate. l-Aspartic acid was produced at an average rate of 2.18 x 10 mol/min per g (wet weight) of immobilized E. coli cells with a 37 degrees C substrate solution consisting of 1.0 M ammonium fumarate with 1 mM Mg (pH 9.0).

We proposed that people's intimates may insulate them against self-discrepant feedback. Individuals who possessed low or high self-esteem (targets) reported to the laboratory accompanied by persons with whom they were involved in intimate relationships (intimates). Some intimates perceived targets in a manner that was congruent with targets' self-conceptions; others perceived targets in a manner that was incongruent with targets' self-conceptions. Targets received bogus feedback that was discrepant with their self-esteem and interacted with either their intimate or a stranger. Targets then completed a measure of self-esteem. As expected, targets changed their self-ratings in the direction of the discrepant feedback when they interacted with either an incongruent intimate or a stranger but not when they interacted with a congruent intimate. Moreover, congruent intimates were just as effective in insulating low self-esteem targets against positive feedback as they were in insulating high self-esteem individuals against negative feedback. Finally, the more targets discussed the feedback, the less self-rating change they experienced. Implications for social support processes and attempts to cope with traumatic events are discussed.