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Yellowing of vegetable oils in coatings continue to be a problem to paint formulators and users and to resin manufacturers. This characteristic occurs in coatings where there is unsaturation in the triglyceride fatty acid residues of the oils used in the resin or binder. Yellowing is the single most important factor which limits the use of linseed oil‐based white paints and enamels for external use in buildings. A thorough understanding of this phenomenon is necessary to the resin manufacturer and paint formulator. Unfortunately, yellowing of vegetable oils in coatings is still a controversial subject. The chemistry behind the process is not yet known. Many factors have been attributed to causing or related to the onset and degree of yellowing. These include:

The adhesive and impact properties of cured epoxy resins, modified with amine‐randomised poly(2‐ethylhexyl acrylate) (ARPEHA) liquid rubber, as a function of the concentration of the liquid rubber, have been investigated. ARPEHA was synthesised by the reaction of the carboxyl‐randomised poly(2‐ethylhexyl acrylate) (CRPEHA) liquid rubber with 4,4′‐diaminodiphenyl sulphone. CRPEHA was synthesised by solution co‐polymerisation of 2‐ethylhexyl acrylate and acrylic acid. ARPEHA modified cured epoxy resins were formed by curing with an ambient temperature‐curing agent, triethylene tetramine. The modified epoxy resins were evaluated with respect to their adhesive and impact properties. The optimum properties were obtained at around 12.5 phr (parts per hundred parts of epoxy resin) of modifier. Analysis of the fracture surface using scanning electron microscopy indicated the presence of two‐phase microstructures.

To evaluate the efficiency of modifying epoxy resin using amine terminated poly(ethylene glycol) benzoate (ATPEGB) for improved toughness and to optimise the results of such a modification.

For effective toughening, various compositions were made by incorporating different concentrations of ATPEGB. The impact and adhesive strengths of the unmodified and modified epoxy networks were characterised.

The modification of epoxy resin using ATPEGB showed significant enhancement of impact and adhesive strengths over the unmodified one. The modification caused a chemical linkage between ATPEGB and resin which led not only to a phase separation but also to ensuring the intrinsically strong chemical bonds across the ATPEGB phase/resin matrix interface, which was the main cause to the improved impact and adhesive strengths. The optimum results were obtained at 12.5 phr (parts per hundred parts of epoxy resin) of modifier.

The modifier, ATPEGB, used in the present context was synthesised from poly(ethylene glycol) (PEG) of molecular weight 600. Besides, it could be synthesised from PEG of molecular weight 200, 400, 4,000, 20,000 etc. In addition, the efficiency of modification of epoxy resin using these could also be studied.

The method developed provided a simple and practical solution to improving the toughness of cured epoxy.

The method for enhanced toughness of cured epoxy was novel and could find numerous applications in surface coating and adhesive.

In the study of entrepreneurial behavior types, “ambitious entrepreneurship” recently emerged as a new research concept. Unfortunately, a systematic overview of what is known (and not known) about this topic is missing. In particular, insights into the various definitions, measures, and antecedents of ambitious entrepreneurship are lacking. In this chapter, we offer a state-of-the-art review and analysis of extant research on ambitious entrepreneurship. We structure the literature review by providing insights into antecedents of ambitious entrepreneurship, and extensively discuss the conceptualization and operationalization of this research concept. We clarify the differences between related concepts such as growth intention, expectation, and aspiration, and argue how all these concepts fit into a unifying framework of ambitious entrepreneurship. We summarize promising future research avenues for the study of ambitious entrepreneurship, both from a methodological and a conceptual point of view.

Since the development of the COVID-19 vaccinations, questions surrounding race have been prominent in the literature on vaccine uptake. Early in the vaccine rollout, public health officials were concerned with the relatively lower rates of uptake among certain racial/ethnic minority groups. We suggest that this may also be patterned by racial/ethnic residential segregation, which previous work has demonstrated to be an important factor for both health and access to health care.

In this study, we examine county-level vaccination rates, racial/ethnic composition, and residential segregation across the U.S. We compile data from several sources, including the American Community Survey (ACS) and Centers for Disease Control (CDC) measured at the county level.

We find that just looking at the associations between racial/ethnic composition and vaccination rates, both percent Black and percent White are significant and negative, meaning that higher percentages of these groups in a county are associated with lower vaccination rates, whereas the opposite is the case for percent Latino. When we factor in segregation, as measured by the index of dissimilarity, the patterns change somewhat. Dissimilarity itself was not significant in the models across all groups, but when interacted with race/ethnic composition, it moderates the association. For both percent Black and percent White, the interaction with the Black-White dissimilarity index is significant and negative, meaning that it deepens the negative association between composition and the vaccination rate.

The analysis is only limited to county-level measures of racial/ethnic composition and vaccination rates, so we are unable to see at the individual-level who is getting vaccinated.

We find that segregation moderates the association between racial/ethnic composition and vaccination rates, suggesting that local race relations in a county helps contextualize the compositional effects of race/ethnicity.

Implicit motives are capacities to experience specific types of incentives as rewarding and specific types of disincentives as aversive (Atkinson, 1957; Schultheiss, 2008). Because implicit motives determine which stimuli are affectively “hot”, they also orient the person's behavior toward those stimuli, energize behavior aimed at attaining (or avoiding) them, and select stimuli that predict their proximity and behaviors that are instrumental for attaining (or avoiding) them (McClelland, 1987).

Since the emergence of a coronavirus disease (2019-nCoV) in December 2019, the whole world is in a state of chaos. Isolation strategy with quarantine is a useful model in controlling transmission and rapid spread. As a result, people remained at home and disrupted their outside daily activities. It led to the closure of educational institutes, which is a source of many students to cope with numerous personal and familial issues. This study aims to focus on exploring the relationships and potential mediational pathways between mental health problems, illness perception, anxiety and depression disorders.

The study incorporated snowball sampling techniques through a cross-sectional, Web-based survey and recruited 500 students from different universities of twin cities, Rawalpindi and Islamabad from March 23 to April 15, 2020, during the coronavirus outbreak lockdown. The study used four instruments, Beck Depression Scale, Beck Anxiety Inventory, Revised Illness Perception Questionnaire and The Warwick-Edinburgh Mental Well-being Scale for assessing depression, anxiety, illness perception and mental health disorders.

The findings indicated normal (43.2%), mild (20.5%), moderate (13.6%) and severe (22.7%) levels of anxiety prevalence in students. Results specified a normal (65.9%), mild (9.10%), moderate (9.12%) and severe (15.90%) depression prevalence and findings stipulated that anxiety disorder prevalence was higher than depression disorder. The correlational results specified a negative and significant relationship between mental health, illness perception, anxiety and depression symptoms. The multiple regression analysis stated that anxiety and depression disorders mediated the relationship between mental health and present illness perception. The perception of illness exhibited a relation to depression and anxiety disorders.

The study proposed a model to address mental health problems during the lockdown. The (2019-nCoV) illness perception developed mental disorders, including anxiety and depression, which has declined individuals’ mental health. There is an urgent need for ongoing clinical examination and management to address psychological disorders and findings suggest assessing mental health to combatting the pandemic worldwide. Findings recommend developing strategies to promote mental health-care facilities during COVID-19 wide-ranging disasters. These results highlight the impending importance of devising strategies to treat mental health problems.

The present study aims to investigate the psychometric properties of the picture story exercise (PSE), a tool for measuring implicit motivations in Iran.

The research method is descriptive correlation and was conducted in two studies. In the first study 24 psychology master’s students were selected by convenience sampling method and tested them to check retest and inter-coder reliability. The second study investigated the correlation between self-reports and the PSE test on a sample of managers. Its statistical population comprised all the managers of a refinery company, 50 people were selected by convenience sampling method. To check the concurrent validity of the PSE test, the participants of the second study, completing the PSE, also completed the needs questionnaire of Steers and Porter (1979).

The findings showed that the PSE test in the Iranian sample had high retest reliability (0.62 on mean) and inter-coder reliability (0.87 on mean), and, following previous research, it does not show a significant relationship with self-reported motives.

PSE can be used in future research as a tool that has demonstrated its reliability and validity in the Iranian sample.

Measurement of implicit motives is a practical factor for predicting people’s behavior, the necessity of using tools that can accurately evaluate implicit motives is strongly felt. Taking into account the fact that so far, in Iranian samples, implicit motivations have not been measured, therefore, the current research is trying to answer this question, whether one of the most important and prominent tools that were made for this purpose and used in various studies can also be used in Iranian samples.

The purpose of this study is to evaluate the impact of food access and other vulnerability measures on the COVID-19 progression to inform the public health decision-makers while setting priority rules for vaccine schedules.

In this paper, the authors used the Supplemental Nutrition Assistance Program (SNAP) data combined with the Centers for Disease Control and Prevention (CDC)’s social vulnerability score variables and diabetes and obesity prevalence in a set of models to assess the associations with the COVID-19 prevalence and case-fatality rates in the United States (US) counties. Using the case prevalence estimates provided by these models, the authors developed a COVID-19 vulnerability score. The COVID-19 vulnerability score prioritization is then compared with the pro-rata approach commonly used for vaccine distribution.

The study found that the population proportion residing in a food desert is positively correlated with the COVID-19 prevalence. Similarly, the population proportion registered to SNAP is positively correlated with the COVID-19 prevalence. The findings demonstrate that commonly used pro-rata vaccine allocation can overlook vulnerable communities, which can eventually create disease hot-spots.

The proposed methodology provides a rapid and effective vaccine prioritization scoring. However, this scoring can also be considered for other humanitarian programs such as food aid and rapid test distribution in response to the current and future pandemics.

Humanitarian logistics domain predominantly relies on equity measures, where each jurisdiction receives resources proportional to their population. This study provides a tool to rapidly identify and prioritize vulnerable communities while determining vaccination schedules.