Abstract
The current study explores the role of white space within advertisements on consumers’ perceptions and the downstream consequences regarding their attitude toward the advertisement. We propose that advertisements with low (vs. high) white space on an advertisement enhances consumers’ perceived confinement about the advertisement (Study 1). Further, advertisements including high (vs. low) white space should increase consumers’ positive attitudes about the advertisement in response to the product image dynamism which is higher, while this is not the case for product image dynamism which is lower (Study 2). Two studies provide support for these propositions. This research not only helps to understand the different interpretations of white space, but also complements the literature on product image dynamism and advertising effectiveness.
Introduction
Many brands incorporate a lot of white space in their advertising. White space, also known as negative space (Farman, 2016) or empty space (G. Wang et al., 2022), is the space around a design, which contains nothing (Sharma & Varki, 2018). The art and design literature suggest that, like other aspects such as color, shape and texture of the object, white space is also an element of visual grammar (G. Wang et al., 2022). In traditional Chinese painting, white space was a considerable means of artistic expression used to separate the viewers from specific scenes, and lead them to perceive abstract, free time and space (Chuan, 2016). For example, in Huang Gongwang’s (1269–1354) Dwelling in the Fuchun Mountains, a painting masterpiece created in the Yuan Dynasty, a large area of white space is applied to express a feeling of spaciousness and freedom. Up to modern times, the rise of white space probably began with the American minimalism movement of the mid-20th century. Henceforward white space was accepted as a convention and was understood not to be “nothing” but is “white space” in American (Pracejus et al., 2013).
As mentioned above, white space is considered an extensively applied tool in the advertising practice and an important artistic expression. Many studies show that in the design and presentation of goods, white space has an impact on consumer perception (Margariti et al., 2022; Sharma & Varki, 2018), such as increasing perceived extravagance and prestige (Olsen et al., 2012). Research also indicate that the sense of confinement and spaciousness are closely related to the size of a space (Meyers-Levy & Zhu, 2007; Okken et al., 2013; Stamps, 2010). Therefore, we wonder if there might be other downstream consequences, such as perceived confinement, of white space in advertising. In addition, many products are depicted as in motion in advertisements. As motion often presupposes corresponding space, motion is closely related to the concept of white space. In consumer behavior studies, product image dynamism, that is, the extent to which motion characteristics of products are conveyed through static images, has received considerable attention. For example, whether it is depicted as moving or not is an important feature of the object in display (Cian et al., 2015; Gvili et al., 2015, 2017). Motion of an object and its velocity have important effects on the position of it (Bressler & Whitney, 2006; Chung et al., 2007; Freyd, 1983a). When an object moves to different positions, it requires different level of space.
Although motion is closely related to space, and both white space and product image dynamism are widely used in advertising, few studies have combined white space and product image dynamism to explore their combined effect on advertising effectiveness. To fill this research gap, in the current research, we investigate the influence of white space on viewers’ perceived confinement and the effectiveness of advertisement depending on the confinement brought by white space in conjunction with the product image dynamism depicted in advertising. We demonstrated the effect whereby a low level of white space enhances the perceived confinement (Study 1). Furthermore, we examine the moderating effect of the product image dynamism in the influence of white space on consumers’ attitudes towards the advertisement (Study 2).
The current study extends the area of downstream consequences of white space. Our research showing how white space influences the effect of advertising triggered by confinement perception. Furthermore, this study extends the research on product image dynamism in advertising. While previous research focused on the impacts of high and low dynamism, the current study expands to the effects of spatial requirements for the product image dynamism. The study also has strategic values for practitioners in visual element design. For product image dynamism which is higher, advertisements with high white space is more effective than low white space condition. However, for product image dynamism which is lower, consumers will have no significant difference in attitudes toward advertisements in response to high and low levels of white space.
Literature Review and Hypothesis Development
White Space
White space is the space around a design that contains nothing (Sharma & Varki, 2018). In the field of art, leaving white spaces in painting can enhance the vitality of the picture and present the artistic conception. This kind of artistic conception can lead viewers beyond specific limited objects, events, and scenes, and into infinite time and space. In traditional Chinese painting, leaving white spaces holds a significant position (G. Wang et al., 2022).
In academic research, especially in consumer-oriented academic research, empirical studies on white space mainly include two types: product image white space and text white space. Jacobs and Poillon (1992) found that ads with less white space are more liked, perceived as being of higher quality, and preferred by customers seeking a store in which to shop. Pracejus et al. (2006) focused on the white space in product images and find that white space can enhance product quality perception, reputation perception, and reduce perceived purchase risk. Their subsequent study discovered that consumers from different cultural backgrounds evaluate white space differently; for example, consumers in India and Hong Kong do not have higher evaluations of advertisements with high white space, while consumers in the United States do, possibly due to the minimalist movement in the U.S. (Pracejus et al., 2013). Additionally, advertising designers believe that white space can reduce clutter and draw customers’ attention away from a crowded media environment (Olsen et al., 2012). A study focusing on white space in e-commerce product images indicated that the total amount of white space on a website does not influence price perception. However, the white space between contents affects male participants’ perception of prices, the more white space between contents, the higher the estimated price (Loh, 2013).
Kwan et al. (2017) shifted their focus from product images to text. Their research indicates that adding white space to textual information reduces the perceived intensity of the information, leading to a poorer persuasive effect. However, this effect is not significant when the source of information is unreliable. Findings indicate that an online store with larger online product catalog space is perceived to be selling more expensive products (Huang et al., 2019). Gupta and Hagtvedt (2021) demonstrate that interstitial space in textual brand logos—that is, spacious (vs. compact) arrangement of letters—unfavorably influences brand attitude by reducing product safety perceptions. A study found that the presence of active white space can make consumers perceive the brand as more dynamic. Besides, when the appeal of the brand is freedom, the perception of brand dynamic aroused by the presence of the brand logo active white space will have a greater impact on consumers’ brand attitude (D. Wang et al., 2023).
In recent years, there have been new developments in the research on white space. Kwak et al. (2020) demonstrate that the existence of space reduces the effectiveness of multiple (vs. single) unit price promotions. Yu et al. (2024) identify two types of white space, termed interspace (space in between a product layout) and circumspace (space surrounding a product layout). They found that when holding the total white space constant, a lower interspace/circumspace ratio, compared with a higher interspace/circumspace ratio, can increase the perceived entitativity of a collection of products in an ad and, ultimately, ad evaluation, purchase intentions, and click-through rates.
About the color of white space, it was found that the hue of the positive space interacts with the color of the white space to determine whether logos communicate positive or negative brand impressions more vividly (Celhay & Luffarelli, 2024). Sharma (2021) investigates the effects of using colored empty space, where prior research has only focused on white empty space. Findings reveal that using a product-colored (vs. white) empty space in an ad increases consumers’ product buying impulse. They also found that enhanced exposure to product color, increased ad salience, and product’s hedonic appeal work as serial processes explaining this effect.
In packaging design, study shows that for low-end products, the lower the white space ratio, the greater the consumer’s willingness to buy, while for high-end products, the higher the white space rate, the lower the consumer’s purchase intention (Wu, 2023). It was also found that simple packaging, which with higher white space, evokes a symbolic association whereby minimizing design complexity signals that the product contains few ingredients, which increases perceived product purity and willingness to pay (Ton et al., 2024).
Although there is considerable research on white space in advertising, one closely related factor that has been overlooked is the product image dynamism widely used in advertisements. Since the motion of objects often requires corresponding space, motion is closely related to white space. It is necessary to explore the joint impact of white space and product image dynamism in advertising.
Product Image Dynamism
In this study, the degree to which products appear dynamic in advertisements through product images suggesting motion is referred to as product image dynamism. This concept stems from the notion of image dynamism as discussed in Cian et al. (2014), which refers to the degree of perceived motion in static images (e.g., paintings, photographs, logos, etc.). When viewing an image of an object, one can tell whether it is moving or static at once because people have the ability to detect motion-related information from a static picture. This kind of motion depicted by a plane image is known as implied motion (Freyd, 1983a), and the degree of motion perception it brings is called dynamism (Cian et al., 2014).
Object dynamism is an important visual element. In the design of advertisements and brand logos, many product manufacturers adopt images with dynamism; for example, cars are depicted as speeding along and the logo of some express companies brings a strong sense of dynamics. Generally, objects with higher dynamism generate more positive effects than those with lower dynamism (Cian et al., 2014, 2015; Gvili et al., 2015, 2017; Yu et al., 2022). For example, in perfume advertisements, dynamic images can increase the perceived intensity of the scent, thereby enhancing its perceived persistence and positively influencing purchase intention (Droulers et al., 2024). In recent years, image dynamism has also been applied in the field of tourism marketing (Li & Ma, 2024; Yu et al., 2023).
However, could these concepts of dynamism in turn influence advertising effectiveness under different levels of white space? Motion and space are closely related. The current study speculates that in advertisements, product image dynamism, interacting with the sense of confinement created by varying degrees of white space, will jointly influence attitudes towards advertisements.
Enhancing Perception of Confinement
Differences in spatial perception can be induced by white space (O’Guinn et al., 2015). For example, O’Guinn et al. primed a subject’s spatial perception through the number of human stick figures in images. In one condition, the image was composed of two stick figures, which included a large amount of white space. In the other condition, the image was composed of 36 stick figures, which included a small amount of white space (O’Guinn et al., 2015). Reducing the white space in an image may decrease perceived spaciousness, which refers to the range of movement within a boundary (Stamps, 2010). Therefore, different white space levels indicate different spatial perceptions.
The sense of confinement is closely related to the size of the space. Restrained physical spaces, such as a very small room, can invoke perceptions of confinement (Meyers-Levy & Zhu, 2007; Okken et al., 2013). In particular, the room size manipulations were found to have an impact on spaciousness perceptions, and further influence self-disclosure (Okken et al., 2013). Compared to a high ceiling, a low ceiling can prime the concept of confinement (Meyers-Levy & Zhu, 2007). Low (vs. high) level of white space in an advertisement may have the same effect as restrained physical space. Taken together, such research leads to the idea that relatively low (vs. high) level of white space in advertisements are likely to decrease perceived spaciousness and prime the concept of confinement. Specifically, we hypothesize the following.
H1: Advertisements with low (vs. high) level of white space may give a sense of greater confinement.
Interaction of White Space and Product Image Dynamism
We assumed that the product image dynamism may interact with the feeling of confinement brought by the white space, thus influencing attitudes toward the advertisement. This can be explained by the close relationship between motion perception, perceived position, space, and sense of confinement.
Implied motion can bring viewers a feeling of movement, and they will simulate this motion process in their cognitive system. The sensitivity of the human perceptual system for extracting movement information from the outside environment is so acute that some feelings similar to movement perception may arise even when movement is not really happening but is only implied (Freyd, 1983a, 1983b). Internalized motor processes make it possible for perceived motion in stationary visual cues to appear as a dynamic feature (Cian et al., 2015). The perception of motion brought by a static photo concurrently facilitates dynamic imagery, along with one mentally simulating the movement of the action depicted in the image (Cian et al., 2015). Natural tendencies to mentally infer the movement of a target stimulus exist (Finke & Freyd, 1985; Finke et al., 1986).
It has been shown that implied motion language can influence visual spatial memory (Vinson et al., 2017). In several studies, the participants were asked to present the position of the previously observed object that implied motion. The position they reported usually moves in the direction of the implied motion (Freyd, 1983a; Freyd & Finke, 1984). The researchers assumed that the participants were simulating the future motion of objects. Consequently, the position of the objects shifts along the direction of its implied motion (Freyd, 1987). Bressler and Whitney (2006) indicated that the value of the visual motion-induced position shift (MIPS) for drifting Gabor patches increased as the velocity increased. Chung et al. (2007) demonstrated that MIPS increased monotonously with the increasing velocity of drifting objects. In a typical test to explore this phenomenon, participants viewed static images of a runner with both lower and higher perceptions of motion. The observers were then asked to reproduce the position of the target after its disappearance. In the case of no contradictory information, the memory displacement of the target was shown to be largest with a higher perception of motion (Kawabe & Miura, 2006).
Due to the perceived shift in position caused by implied motion and its velocity, objects depicted as moving at higher speeds require more space and fewer constraints compared to those depicted as static or moving at low speeds. In general, movement requires space. Insufficient space leads to feelings of confinement, which is detrimental to movement. When the low confinement provided by a high level of white space aligns with consumers’ expectations of higher perceived movement, they tend to have more positive attitudes toward advertisements featuring such white space. When consumers are presented with a product image exhibiting lower dynamism, their attention to space does not noticeably increase. They will not be so sensitive to the perception of low confinement brought by high level of white space. Thus:
H2a: For product images with higher dynamism, consumers will have more positive attitudes toward advertisements in response to the high level of white space.
H2b: For product images with lower dynamism, there are no significant differences in consumers’ attitudes toward advertisements in response to high and low levels of white space.
Two studies were conducted to test the proposed hypotheses. We tested whether a low (vs. high) level of white space enhances perceived confinement in Study 1. Next we examine the moderating effect of the product image dynamism in the influence of white space on consumers’ attitudes towards the advertisement in Study 2. We also repeated hypothesis 1 in Study 2.
Study 1
The main aim of Study 1 is to test whether a product imagery with low (vs. high) level of white space may be perceived as greater confinement (H1). Study 1 manipulates white space for an advertisement.
Method
Stimuli
Based on extant research (Kwan et al., 2017; Pracejus et al., 2013), we designed two advertisements including significantly different levels of white space (high vs. low). We choose a bicycle image as the main element of the advertisements. The product image was placed in the center of the advertisement page. Each product image on the different advertisements was identical in size and position. Then, we obtained two different advertisement conditions: high and low levels of white space (Figure 1).

Stimuli in Study 1.
Main Study
Participants
Study 1 recruited participants through the Wenjuanxin (https://www.wjx.cn) online platform. One hundred and ten participants were recruited for a monetary incentive.
Procedure
Upon accessing the interface, participants were allocated to one of two experiment conditions (high vs. low level of white space) at random. After shown a brief instruction and informed consent to participate, they completed a product survey. They were shown the advertisements with either high or low level of white space and asked to rate how much white space was in the advertisement and how confining the product in the advertisements seemed. Next, they finished the demographic items.
Measures
The level of white space was measured by ask them how much white space was in the advertisement (1—not at all, 7—a lot). The perceived confinement was measured by one item: “The degree of confined that you feel about the product in the advertisement?”: “1—not at all, 7—very much” (Fajardo et al., 2016).
Results
After removing invalid responses (i.e., those from participants who did not agree to participate or responded incorrectly to the validation item), Study 1 obtained valid data from 80 participants (76.3% female, Mage = 21.75, SD = 3.37). The age distribution is as follows: 0 to 20 (37, 46.2%), 21 to 30 (42, 52.5%), 31 and above (1, 1.3%). The participants in the two experimental conditions were 39 and 41 respectively.
Manipulation Check
Their ratings demonstrated significant differences in the degree of white space between the two advertisements [Mhigh = 5.63, SDhigh = 1.04; Mlow = 3.87, SDlow = 1.36; F(1, 78) = 62.08, p = .000].
Perceived Confinement
The main effect was tested by one-way analysis of variance. Results shows that participants perceived the advertisement including low level of white space as depicting more confining [Mhigh = 3.54, SDhigh = 1.34; Mlow = 4.90, SDlow = 1.48; F(1, 78) = 18.53, p = .000]. In addition, gender and white space had no interaction effect on perceived confinement (F < 1). Consequently, hypothesis 1 was supported.
Discussion
Study 1 provided empirical evidence supporting H1, with high (vs. low) level of white space resulting in lower perceived confinement. We also want to know if the difference in white space influence the advertising effectiveness and the effect of product image dynamism in the advertisement. Next, we tested the moderated mediation effect.
Study 2
In this study, we test H2a and H2b, which proposed that, for the product image with higher dynamism, advertisements imagery with high level of white space would bring a more positive attitude about the advertisement than that with level of low white space. For the product image with lower dynamism, high (vs. low) level of white space would lead to no significant different attitude toward the advertisement. We conducted a 2 (white space: high vs. low) × 2 (product image dynamism: higher vs. lower) between-participants experiment in Study 2.
Method
Stimuli
A car was chosen as the product in the advertisements. We designed two car images. In one image, the car is depicted as stationary, and in the other image, the car is depicted as rapidly moving forward through elements such as motion blur (Figure 2). For each car image, we designed a low and a high white space version of advertisement like Study 1.

Stimuli in Study 2.
Main Study
Participants
Study 2 recruited participants through the Wenjuanxin online platform. One hundred and ninety-two participates were recruited to take part in the experiment and were given a monetary reward.
Procedure
After shown a brief instruction and informed consent to participate, participants were randomly assigned to one of four experiment groups. They were told they would view a car advertisement and asked to accomplish a product survey where they were shown advertisements in which the product image with higher or lower dynamism in either high or low level of white space. Then, they were asked to rate how much white space was and their perceived movement of the car in the advertisement. After that, they finished items that captured their levels of perceived confinement and attitudes toward the advertisements. Lastly, participants responded to the demographic items.
Measures
One item was used to measure their perceived movement of the car (1—no movement at all, 7—a lot of movement) (Cian et al., 2014). For attitude toward the advertisement, three 7-point bipolar items were used (1—dislike/unfavorable/negative, 7—like/favorable/positive) (α = .894) (MacKenzie et al., 1986). The scales used in the measurement of the degree of white space and perceived confinement were consistent with Study 1.
Results
After deleting some invalid responses (i.e., responses from those who do not agree to participate, scores for all scale questions are the same, and the validation item is responded incorrectly), Study 2 obtained valid data of 142 participants (62.7% female, Mage = 22.28, SD = 3.83). The age distribution is as follows: 0 to 20 (51, 35.9%), 21 to 30 (85, 59.9%), 31 and above (6, 4.2%). The participants in the four experimental groups were 37, 34, 34, and 37 respectively.
Manipulation Check
The scores of the degree of white space showed significant differences between the high and low levels of white space conditions [Mhigh = 5.14, SDhigh = 1.11; Mlow = 3.48, SDlow = 1.25; F(1, 140) = 69.93, p = .000]. Their ratings also demonstrated significant differences in the perceived movement between the higher and lower dynamism conditions [Mhigh = 4.76, SDhigh = 1.13; Mlow = 3.23, SDlow = 1.35; F(1, 140) = 53.90, p = .000].
Perceived Confinement
Participants assigned to the high level of white space condition expressed significantly lower levels of perceived confinement [Mhigh = 4.00, SDhigh = 1.47; Mlow = 4.83, SDlow = 1.49; F(1, 140) = 11.14, p = .001]. In addition, gender and white space had no interaction effect on perceived confinement (F < 1). Hypothesis 1 was supported again.
Moderation Effect of Product Image Dynamism
The two-way interaction was significant in a 2 (white space: high vs. low) × 2 (product image dynamism: higher vs. lower) ANOVA on advertisement attitude [F(1, 138) = 4.22, p = .042], which reflected the predicted pattern. Particularly, simple effect analysis found that for the advertisement in which the product image with higher dynamism, high level of white space generated more positive attitudes toward the advertisement [Mhigh = 4.61, SDhigh = 1.01; Mlow = 3.96, SDlow = 1.24; F(1, 139) = 6.14, p = .014] than did low level of white space. In contrast, for the advertisement in which the product image with lower dynamism, either conditions (high vs. low level of white space) generated similar favorable attitudes toward the advertisement [Mhigher = 3.82, SDhigher = 1.13; Mlower = 3.95, SDlower = 1.11; F(1, 139) = 0.15, p = .697]. Thus, the H2a and H2b were supported.
Moderated Mediation
To estimate moderated mediation for two-way interactions, we resampled 5,000 samples using the mediation analysis method (model 14). For the advertisement in which the product image with higher dynamism, the mediation effect whereby white space influences perceived freedom, which further have an effect on attitude toward the advertisement, is significant (B = 0.37, 95% CI = [0.138, 0.650]). For the advertisement in which the product image with lower dynamism, the effect whereby white space affects attitude toward the advertisement (B = 0.11, 95% CI = [−0.035, 0.311]) through affecting perceived freedom is not significant. The interaction effect of perceived confinement and product image dynamism on attitudes toward advertisement is significant (B = 0.30, 95% CI = [−0.532, −0.067]). The H2a and H2b were supported again.
Conclusions and Discussion
Conclusions
The present study examined a common design feature of advertising, white space. Across two studies, evidence is offered for a framework that associates white space with a sense of confinement. We demonstrated the effect whereby a low (vs. high) level of white space enhances the perception of confinement (Study 1). Furthermore, for product image with higher dynamism, consumers will have more positive attitudes toward advertisements in response to the high level of white space. For product image with lower dynamism, there are no significant differences in consumers’ attitudes toward advertisements in response to high and low levels of white space (Study 2).
Theoretical Implications
Several contributions have been made in the current study. First, it offers a better understanding of white space (Kwan et al., 2017; Pracejus et al., 2006; D. Wang et al., 2023; Yu et al., 2024). Given white space is a common tool in advertising practice, the results about the relationship between white space and perceived confinement are important. Past work demonstrates that presence of white space enhances perceived quality, prestige and leadership (Pracejus et al., 2006). We extended this previous work by identifying a new symbolic associations of white space. In our context, low (vs. high) level of white space increases a sense of confinement in advertising. Given the importance of environmental variables in advertising, greater knowledge about the environmental variables that affect consumer’ advertisement attitude is important to better improve the advertising effectiveness.
Second, the feeling of confinement generated by white space affects consumers’ attitudes toward advertisements in conjunction with product image dynamism in the advertising. Previous studies have explored the impact of culture (Pracejus et al., 2013), shop categories (O’Guinn et al., 2015), and white space type (Yu et al., 2024) on the effect of white space, but few have explored the impact of the characteristics depicted in advertising on the effect of white space. We identified different downstream consequences of white space and the intrinsic mechanism and boundary condition of the above influence process by demonstrating that product image dynamism may interact with the confinement perception generated by the white space in advertising design, leading to different attitudes toward advertisements.
Third, previous studies on advertising with higher (vs. lower) dynamic images discuss the different influences of such images on downstream variables under the condition of consistent white space (Cian et al., 2014, 2015; Li & Ma, 2024; Yu et al., 2022, 2023). In most cases, object images with higher dynamism lead to more positive advertising attitudes (Cian et al., 2014, 2015; Gvili et al., 2015, 2017). However, previous studies have not explored whether there is a difference in the influence of higher (vs. lower) dynamic images on downstream variables in the case of confined space. Our study suggests that a higher dynamic may no longer be an advantage once the degree of confinement has increased.
Practical Implications
Space environment design and the core elements of advertising are equally important. White space is an integral part of an advertisement and is widely used in advertising practice. Thus, our findings are highly relevant to advertising practice. The current study emphasizes advertising effectiveness may benefit from the uniformity of advertisements style. Our findings suggest that a one-size-fits-all design may be not always useful. Therefore, in order to improve advertising effectiveness, marketing practitioners need to have a clear understanding of product characteristic depicted in advertising and advertising white space design. For example, due to budget constraints on advertising space and the desire to convey as much information as possible within limited space, many advertisers adopt a design style with very little white space. However, this style can create a strong sense of confinement for the viewers, especially when the product depicted in the advertisement is shown in motion, which can negatively impact the advertising effectiveness.
Limitations and Future Research Direction
Currently, this study has only introduced dynamism into research on white space, considering only the impact of implied motion versus stillness. However, motion encompasses other characteristics such as speed, direction, and forces involved during motion. These factors are all spatially related. For instance, high-speed motion may require more space compared to low-speed motion, and motion in different directions may also vary in spatial demands. Therefore, these factors influence viewer perception and potentially affect the interaction between product image dynamism and white space in advertising effectiveness. Hence, future research could further expand on this aspect.
In this study, the importance of confinement is increased through product characteristic depicted in advertising. There are also some other ways to arouse the concerned about space, such as through the slogan (Fajardo et al., 2016). Thus, rather than focus on product characteristic depicted in advertising, future research might consider other design elements, such as different advertising appeals (e.g., freedom appeals vs. safety appeals), that have possible match-up effects with various dimensions of white space.
In addition, spatial properties can also influence people’s information processing style (Meyers-Levy & Zhu, 2007; Plambech et al., 2015; Van Rompay & Jol, 2016). Scholars (Plambech et al., 2015; Van Rompay & Jol, 2016) have found the positive impacts of spaciousness which can generate freedom-related feelings on individuals’ creative thought and performance. More direct evidence comes from Meyers-Levy and Zhu (2007), in whose research they demonstrated that freedom-related feelings encouraged a more global, abstract information processing style. Does white space encourage a more abstract cognition? Further, whether there is a matching effect between white space and different advertising appeals? Such as rational appeals, these appeals are processed by consumers using logic, analytical and sequential thinking, while emotional appeals are processed holistically (Kim et al., 2017). Future work could explore whether the white space has an impact on people’s information processing style, and the matching effect with the advertising appeals.
Footnotes
Declaration of Conflicting Interests
The author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.
Funding
The author(s) received no financial support for the research, authorship, and/or publication of this article.
Data Availability Statement
Data will be made available from the authors on reasonable request.
