Robust estimation of bacterial cell count from optical density

Optical density (OD) is widely used to estimate the density of cells in liquid culture, but cannot be compared between instruments without a standardized calibration protocol and is challenging to relate to actual cell count. We address this with an interlaboratory study comparing three simple, low-cost, and highly accessible OD calibration protocols across 244 laboratories, applied to eight strains of constitutive GFP-expressing E. coli. Based on our results, we recommend calibrating OD to estimated cell count using serial dilution of silica microspheres, which produces highly precise calibration (95.5% of residuals <1.2-fold), is easily assessed for quality control, also assesses instrument effective linear range, and can be combined with fluorescence calibration to obtain units of Molecules of Equivalent Fluorescein (MEFL) per cell, allowing direct comparison and data fusion with flow cytometry measurements: in our study, fluorescence per cell measurements showed only a 1.07-fold mean difference between plate reader and flow cytometry data

Romantic crushes promote variety-seeking behavior

Consumers making repeat consumption choices often need to decide whether to stick to their favorite option or to select something different. Understanding the situational factors that influence their willingness to seek more or less variety in consumption is of both theoretical and practical importance. The current research proposes that a salient relationship state—romantic crush—can increase consumers’ variety-seeking tendency in unrelated consumption situations. Building on the compensatory consumption literature, we suggest that the lack of reciprocal response in the romantic crush experience may lower consumers’ sense of control in the romantic relationship. Therefore, they are motivated to restore their sense of control by making more varied choices in consumption domains. Five studies provide support for this hypothesis. In line with our control restoration account, the effect disappears when consumers’ sense of control is boosted via other means. Moreover, the effect is specific to the experience of a romantic crush and cannot be generalized to other types of romantic relationship (e.g., initial stage of love).MOE (Min. of Education, S’pore)Accepted versio

The impact of death-related media information on consumer value orientation and scope sensitivity

This research examines how incidental exposure to death-related information in the media affects consumers’ value orientation and scope sensitivity to marketing stimuli. Five studies demonstrate that, in contrast to thoughts about one's own mortality, exposure to death-related information in the media can shift consumers’ focus from extrinsic to intrinsic values. This leads them to pay less attention to the marketing stimuli, which are generally associated with extrinsic values, and consequently results in lower sensitivity to the magnitude of products and services. These effects are reversed when the marketing stimuli are associated with intrinsic values. Moreover, we found that exposure to death-related media information will generate effects similar to those of mortality salience when the information is perceived to be self-relevant and thus could induce death anxiety. The authors discuss implications and possible extensions.MOE (Min. of Education, S’pore

Crush on you : romantic crushes increase consumers’ preferences for strong sensory stimuli

What influences consumers’ preferences for strong versus weak sensory stimuli? In this article, we find converging evidence that when the experience of a romantic crush is salient, consumers have an enhanced preference for options that elicit strong sensory stimulation (e.g., loud music, strongly flavored food). We demonstrate this effect across seven studies using a broad array of products and services as stimuli. We further show that these consumers have a heightened motivation to achieve greater sensations from the desired person, but cannot act in a way that directly satisfies this motivation, leading them to be more likely to turn to products and services for the desired sensations. Moreover, we find that the effect is specific to the experience of a romantic crush and cannot be generalized to other interpersonal experiences (e.g., passionate love, stable romantic relationship, unmet sexual desire).MOE (Min. of Education, S’pore)Published versio

The influence of social crowding on brand attachment

Feeling crowded in a shopping environment can decrease consumers’ evaluations of a product or service and lower customer satisfaction. However, the present research suggests that a crowded environment can sometimes have a positive impact on consumer behavior. Although feeling crowded motivates consumers to avoid interacting with others, it leads them to become more attached to brands as an alternative way of maintaining their basic need for belongingness. The effect does not occur (a) when the crowding environment is composed of familiar people (and, therefore, is not considered aversive); (b) when individuals have an interdependent self-construal (and consequently, high tolerance for crowdedness); (c) when people are accompanied by friends in the crowded environment; (d) when the social function of the brands is made salient; (e) when people have never used the brand before; or (f) when the brand is referred to as a general product rather than a specific brand.Published versio

Slowing down in the good old days : the effect of nostalgia on consumer patience

Nostalgia, which is induced by reminiscing about a positive past experience, can counteract loneliness and promote prosocial behavior. However, the process of recalling and thinking about a nostalgic experience can have quite different effects. Because nostalgic experiences rarely reoccur, people are motivated to savor them by prolonging the time they reminisce about them. The tendency to savor these experiences generalizes to situations that participants encounter later, thus increasing consumer patience. For this effect to emerge, however, consumers must be aware that waiting will be beneficial to the attainment of a benefit. Moreover, the relationship between nostalgia and consumer patience is diminished when people perceive a nostalgic experience to be repeatable or when they intensify their memory of the experience rather than prolonging it. Eight studies confirmed these effects and processes that underlie them.Published versio

Feeling disconnected from others : The effects of ambient darkness on hedonic choice

This research documents a novel effect of ambient lighting on consumer choice. We propose and find that ambient darkness (vs. brightness) can result in consumers feeling disconnected from others. As a result, consumers become more authentic in their choices and they choose hedonic over utilitarian options because these choices reflect what they truly want (Study 1). Past research had suggested darkness increases hedonic choice by making choice less observable, but we find this effect emerges even when the choice is already anonymous and darkness cannot further increase anonymity. Rather, feeling disconnected from others and less weight to social norms heightened self-authenticity in darker (vs. brighter) surroundings (Study 2). When consumers are reminded of social connection, this difference is attenuated (Study 3). Thus, consumers making hedonic choices regulate their choices when reminded of their social connections. Implications of these findings and possible extensions are discussed.Accepted versio

Proud to Belong or Proudly Different? Lay Theories Determine Contrasting Effects of Incidental Pride on Uniqueness Seeking

This research examines how incidental pride may increase consumers' tendency to seek uniqueness, depending on how they attribute the pride-inducing experience. Specifically, people who attribute their felt pride to personal traits (i.e., hubristic pride) are more likely to prefer unique options in unrelated situations, compared to tho'se who attribute pride to effort (i.e., authentic pride). This effect is driven by a heightened need for uniqueness (studies 1-3). Importantly, consumers' lay theories of achievement determine these contrasting attributions: consumers who hold an entity (vs. incremental) theory tend to attribute their felt pride to their traits (vs. efforts), and this motivates them to seek uniqueness (studies 4-5). Consumers who feel proud due to effort, but believe the effort was special to themselves, seek similarly high levels of uniqueness as those who attribute pride to their traits-which demonstrates further evidence for our proposed process (study 6). Implications and possible extensions are discussed