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White teeth can give confidence and tend to be associated with a healthier lifestyle in modern society. Therefore, tooth-bleaching strategies have been developed, including the use of hydrogen peroxide. Recently, peroxymonosulfate has been introduced as an alternative bleaching method to hydrogen peroxide. Although both chemicals are oxidizing agents, their effects on the molecular composition of the stained teeth are yet unknown. In this study, the molecular profiles of teeth bleached with hydrogen peroxide and peroxymonosulfate were compared using Liquid Chromatography-Tandem Mass Spectrometry. Statistical analyses were used to assess the samples. In addition, reference spectral libraries and in silico tools were used to perform metabolite annotation. Overall, principal component analysis showed a strong separation between control and hydrogen peroxide and peroxymonosulfate samples (p

Managers' leadership style has a substantial impact on employee and organizational outcomes. In the present study, we consider the role of leaders' chronological age in predicting followers' perceptions of their leadership style. Whereas ample research uncovers relationships between individuals' age and how these individuals are perceived by others, little is known about how leaders' chronological age impacts others' perceptions of their style. Even less is known about how such relationships vary across cultures and industries. We conducted a meta‐analysis (164 unique studies; N = 397,456 observations) to explore these relationships, using the Full‐Range leadership model. We found that leader age was negatively related to perceptions of transformational and transactional leadership, and positively related to perceptions of passive leadership. Further, some of these effects varied on several cultural dimensions: The negative relationship between leader age and transformational leadership was weaker in collectivistic cultures, while the negative relationship with transactional leadership was stronger in high power distance cultures. Industry type also mattered: the relationship between leader age and both transformational and contingent reward leadership styles was amplified in the public sector. Lastly, perceptions of older leaders were more negative when ratings were provided by followers rather than the leaders themselves. Our findings offer both theoretical and practical implications for leading in an increasingly age‐diverse workforce, such as better informing the workforce of present age stereotypes and their imminent effect on organizations. [ABSTRACT FROM AUTHOR]

In this study, we report the synthesis of a new type of chiral crystalline organic porous salt CF2 derived from the ionic reaction between tetrakis(4‐sulfophenyl)methane (TSPM) and the tetra‐(S)‐prolylamide of tetrakis(4‐aminophenyl)methane, (S)‐TPPM, and its ability to stabilize 2 nm palladium nanoparticles to give a novel, nonpyrophoric, chiral, catalytic material Pd@CF2. The preparation of the catalyst was very simple and conducted in water. The heterogeneous catalytic performance of Pd@CF2 was tested in hydrogen reductions of olefins and substituted nitroaromatic compounds using Pd/C as a comparison to determine the specific features of the novel catalyst. Although both types of catalysts exhibited similar catalytic activity in case of reductions of diphenylacetylene and nitrobenzene, Pd@CF2 predominantly promoted the reduction of p‐nitrobenzaldehyde to p‐aminobenzyl alcohol whereas Pd/C gave p‐toluidine. The reduction of p‐dinitrobenzene led to predominant formation of p‐nitrophenylhydroxylamine if promoted by the novel catalyst and to a mixture of products if promoted by Pd/C. In addition, the introduction of p‐alkoxy groups onto nitrobenzenes slowed down the reduction with Pd@CF2 but had no influence on Pd/C activity. A hypothesis ascribing these observations to dissimilar equilibrium distributions of nitro and polar groups within the organic framework and the palladium metal surface is proposed to rationalize the selectivity of the novel catalytic material. [ABSTRACT FROM AUTHOR]

The aim of the work was to achieve the Italian validation of the Succession, Identity, and Consumption Scale of Prescriptive Ageism (SIC) developed by North and Fiske. SIC is a measure of prescriptive ageism, which incorporates intergenerational tensions over practical and symbolic resources. To evaluate the psychometric properties of the Italian version of the scale, two studies were conducted. Study 1 included 931 Italian participants (mean age: 30.94; range: 18–67 years; 50.5% female) and was conducted to test the scale's structure and construct validity. Study 2 comprised 1015 Italian participants (mean age: 30.73 years; age range: 18–67; 53.5% female) and investigated the scale's structure, construct validity, and invariance by gender and age. Confirmatory factorial analyses confirmed the three-factor solution to be invariant across sex and age groups. The scale also demonstrated high internal reliability. SIC scores correlated positively with traditional measures for detecting prejudice and stereotypes towards older people. The results of the present work show that the SIC scale of Prescriptive Ageism is a valid tool for measuring prescriptive beliefs about older adults that are the basis of intergenerational tensions. [ABSTRACT FROM AUTHOR]

Intergenerational conflict appears frequently in American public discourse, often framed as clashes between Millennials and Baby Boomers. Building on intergroup threat theory in an exploratory survey, a preregistered correlational study, and a preregistered intervention (N = 1,714), we find that (a) Millennials and Baby Boomers do express more animosity toward each other than toward other generations (Studies 1–3); (b) their animosity reflects asymmetric generational concerns: Baby Boomers primarily fear that Millennials threaten traditional American values (symbolic threat) while Millennials primarily fear that Baby Boomers's delayed transmission of power hampers their life prospects (realistic threat; Studies 2–3); (c) finally, an intervention challenging the entitativity of generational categories alleviates perceived threats and hostility for both generations (Study 3). These findings inform research on intergroup threat, provide a theoretically grounded framework to understand intergenerational relations, and put forward a strategy to increase harmony in aging societies. [ABSTRACT FROM AUTHOR]

Fundamental questions in bud dormancy remain, including what temperatures fulfill dormancy requirements (i.e. chill accumulation). Recent studies demonstrate freezing temperatures promote chill accumulation and cold hardiness influences time to budbreak—the phenotype used for dormancy evaluations. Here we evaluated bud cold hardiness and budbreak responses of grapevines (Vitis hybrids) throughout chill accumulation under three treatments: constant (5 °C), fluctuating (−3.5 to 6.5 °C daily), and field conditions (Madison, WI, USA). Chill treatments experiencing lower temperatures promoted greater gains in cold hardiness (field>fluctuating>constant). All treatments decreased observed time to budbreak with increased chill accumulation. However, perceived treatment effectiveness changed when time to budbreak was adjusted to remove cold acclimation effects. Among three classic chill models (North Carolina, Utah, and Dynamic), none was able to correctly describe adjusted time to budbreak responses to chill accumulation. Thus, a new model is proposed that expands the range of chill accumulation temperatures to include freezing temperatures and enhances chill accumulation under fluctuating temperature conditions. Most importantly, our analysis demonstrates that adjustments for uneven acclimation change the perceived effectiveness of chill treatments. Therefore, future work in bud dormancy would benefit from simultaneously evaluating cold hardiness. [ABSTRACT FROM AUTHOR]

Public and academic discourse on ageism focuses primarily on prejudices targeting older adults, implicitly assuming that this age group experiences the most age bias. We test this assumption in a large, preregistered study surveying Americans' explicit sentiments toward young, middle-aged, and older adults. Contrary to certain expectations about the scope and nature of ageism, responses from two crowdsourced online samples matched to the US adult population (N = 1,820) revealed that older adults garner the most favorable sentiments and young adults, the least favorable ones. This pattern held across a wide range of participant demographics and outcome variables, in both samples. Signaling derogation of young adults more than benign liking of older adults, participants high on SDO (i.e., a key antecedent of group prejudice) expressed even less favorable sentiments toward young adults--and more favorable ones toward older adults. In two follow-up, preregistered, forecasting surveys, lay participants (N = 500) were generally quite accurate at predicting these results; in contrast, social scientists (N = 241) underestimated how unfavorably respondents viewed young adults and how favorably they viewed older adults. In fact, the more expertise in ageism scientists had, the more biased their forecasts. In a rapidly aging world with exacerbated concerns over older adults' welfare, young adults also face increasing economic, social, political, and ecological hardship. Our findings highlight the need for policymakers and social scientists to broaden their understanding of age biases and develop theory and policies that ponder discriminations targeting all age groups. [ABSTRACT FROM AUTHOR]

The regioselective synthesis of carbamates from bio‐derived cyclic carbonates and amines by using 1,5,7‐triazabicyclo[4.4.0]dec‐5‐ene (TBD) as an organocatalyst is reported. This methodology led to the preparation of a wide range of bio‐sourced hydroxyurethanes from furan‐, carvone‐ and limonene‐based scaffolds under solvent‐free and mild reaction conditions. Moreover, a comprehensive analysis of the process allowed us to optimize the catalyst loading with little or no impact on the process regioselectivity. [ABSTRACT FROM AUTHOR]

Phenolation is one of the effective strategies to synthesize lignin-based polyphenols, improve lignin's properties, and extend its value-added applications in biological, medicinal and cosmetic fields. Herein, by taking the structural feature advantage of lignin, an effective and green strategy was developed to molecularly engineer lignin into a robust lignin-3-(2-hydroxyphenyl)propionate ester (LPPE) derivative via a transesterification reaction between 3,4-dihydrocoumarin (DHC) and the aliphatic hydroxyls in lignin under organocatalysis. The strategy is optimized and the novel derivative was systematically characterized by 1 H, 13 C and 31 P nuclear magnetic resonance (NMR) and Fourier transform infrared (FT-IR) spectroscopy. The findings indicated that the successful introduction of 3-(2-hydroxyphenyl)propionate groups using a OH groups/DHC/organic base molar ratio of 1-1 -0.3 at 120 °C for 6 h increased the content of phenolic hydroxyl groups from 1.793 1 to 3.017 9 mmol/g, and the LPPE exhibited excellent ultraviolet-absorbing and antioxidant performance with up to 90% free radical scavenging activity within 20 min using 5 mg/mL of LPPE. In addition, good biocompatibility and a high Sun protection factor (SPF) value of 40.9 were achieved at 5% (w) dosage of LPPE in the cream, indicating its significant application potential in sunscreen. [ABSTRACT FROM AUTHOR]

Background Dormancy of buds is an important phase in the life cycle of perennial plants growing in environments where unsuitable growth conditions occur seasonally. In regions where low temperature defines these unsuitable conditions, the attainment of cold hardiness is also required for survival. The end of the dormant period culminates in budbreak and flower emergence, or spring phenology, one of the most appreciated and studied phenological events – a time also understood to be most sensitive to low-temperature damage. Despite this, we have a limited physiological and molecular understanding of dormancy, which has negatively affected our ability to model budbreak. This is also true for cold hardiness. Scope Here we highlight the importance of including cold hardiness in dormancy studies that typically only characterize time to budbreak. We show how different temperature treatments may lead to increases in cold hardiness, and by doing so also (potentially inadvertently) increase time to budbreak. Conclusions We present a theory that describes evaluation of cold hardiness as being key to clarifying physiological changes throughout the dormant period, delineating dormancy statuses, and improving both chill and phenology models. Erroneous interpretations of budbreak datasets are possible by not phenotyping cold hardiness. Changes in cold hardiness were very probably present in previous experiments that studied dormancy, especially when those included below-freezing temperature treatments. Separating the effects between chilling accumulation and cold acclimation in future studies will be essential for increasing our understanding of dormancy and spring phenology in plants. [ABSTRACT FROM AUTHOR]

Five nitrogen sources (glycine, β‐alanine, urea, melamine and nicotinamide) and three heating methods (thermal, monomodal microwave and multimodal microwave) are used to prepare nitrogen‐doped Starbons® derived from starch. The materials are initially produced at 250–300 °C (SNx300y), then heated in vacuo to 800 °C to produce nitrogen‐doped SNx800y's. Melamine gives the highest nitrogen incorporation without destroying the Starbon® pore structure and the microwave heating methods give higher nitrogen incorporations than thermal heating. The carbon dioxide adsorption capacities of the nitrogen‐doped Starbons® determined gravimetrically, in many cases exceed those of S300 and S800. The carbon dioxide, nitrogen and methane adsorption isotherms of the most promising materials are measured volumetrically. Most of the nitrogen‐doped materials show higher carbon dioxide adsorption capacities than S800, but lower methane and nitrogen adsorption capacities. As a result, the nitrogen‐doped Starbons® exhibit significantly enhanced carbon dioxide versus nitrogen and methane versus nitrogen selectivities compared to S800. [ABSTRACT FROM AUTHOR]

Background and Objectives Globally aging populations raise worldwide concerns about how an older population will be valued. Cross-culturally, many espouse that Eastern cultures revere their older adults more than Westerners, due to stronger collectivism and filial piety traditions. In contrast, this paper proposes a resource tension hypothesis, whereby rapid population aging causes pragmatic strain across all modernized societies, fostering ageism. Research Design and Methods Three studies supported this resource tension hypothesis, focusing on the pragmatic role of public pensions—a fundamental resource inherently pitting older versus younger generations—in fostering ageism. Study 1 tested the relationship between nation-level public pension rate and attitudes toward older adults by using World Values Survey and European Social Survey data sets. Study 2 further explored this relationship via priming both the pension-based resource scarcity and the intergenerational competition over the public pension. Study 3 offered an intervention—future-self-thinking via a photo ager—on reducing intergenerational tensions under pension scarcity conditions. Results Study 1 found a significant link between nation-level public pension rate and negative older adult attitudes across 39,700 World Values Survey, and 29,797 European Social Survey data points. Study 2 further supported the pension-ageism link via experimental methods. Participants who were reminded of the scarcity of pensions and intergenerational competition exhibited more negative attitudes toward older adults. Study 3 confirmed the effect of the future-self intervention on enhancing attitudes toward older adults even despite scarce pension resources. Discussion and Implications The findings support a resource explanation in driving perceptions of older adults, implicate pensions as a key mechanism driving intergenerational attitudes, and identify future-self thinking as a critical intervention. The present studies open up new research pathways for understanding and accommodating the globally aging population. [ABSTRACT FROM AUTHOR]

Losing a job is one of life's most stressful events. Furthermore, maladaptive reactions to unemployment can trap people in a vicious cycle that derails their reemployment efforts. The current research tested whether a brief values-based self-affirmation intervention increases the odds of reemployment after a job loss and during unemployment, which presumably breaks this vicious cycle. Two field experiments, including one with a governmental employment agency, found that a 15-min self-affirmation exercise--i.e., reflecting on one's most important values--increased key employment-related outcomes after 4 wk, including the probability and speed of reemployment and the number of job offers. Because the ordeal of job loss and the probability of reemployment may be particularly challenging for individuals above the age of 50 y, we also explored whether the intervention was equally effective for those above and below 50 y of age. Demonstrating the generality of this effect, the efficacy of the intervention did not differ between individuals below and above the age of 50, and it was also effective for both recently unemployed and chronically unemployed individuals. Because self-affirmations have more typically been tested in educational contexts, the current research demonstrates the wide-ranging value of this intervention. By diminishing the vicious cycle of unemployment, the present studies show how a simple self-affirmation intervention can help individuals succeed in the labor market. [ABSTRACT FROM AUTHOR]

The use of potassium hydroxide activated Starbons® derived from starch and alginic acid as adsorbents for 29 volatile organic compounds (VOCs) was investigated. In every case, the alginic acid derived Starbon (A800K2) was found to be the optimal adsorbent, significantly outperforming both commercial activated carbon and starch derived, activated Starbon (S800K2). The saturated adsorption capacity of A800K2 depends on both the size of the VOC and the functional groups it contains. The highest saturated adsorption capacities were obtained with small VOCs. For VOC's of similar size, the presence of polarizable electrons in lone pairs or π‐bonds within non‐polar VOCs was beneficial. Analysis of porosimetry data suggests that the VOC's are being adsorbed within the pore structure of A800K2 rather than just on its surface. The adsorption was completely reversible by thermal treatment of the saturated Starbon under vacuum. [ABSTRACT FROM AUTHOR]