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People from diverse ethnic groups or geographical climates may experience different thermal sensations in the same environment (Nakano et al. 2002). Some studies have demonstrated ethnic differences in preferred air temperatures and perception of the thermal environment (Nakano et al. 2002; Knez and Thorsson 2006; Havenith et al. 2020); others report no differences (Watson et al. 2005; Kurazumi et al. 2016). Physiological and psychological differences between ethnicities could influence how people interpret the thermal environment (Brager and De Dear 1998; Taylor 2006), with variations occurring genetically (Long and Kittles 2003; Bamshad et al. 2004), phenotypically (Taylor 2006), as well as through cultural and societal factors (Knez and Thorsson 2008; Xiong et al. 2019; He et al. 2020). Physiologically, humans sense the thermal environment via thermoreceptors, specialised nerve fibres in the skin (Kashio and Tominaga 2022). Thermal information is transmitted to the brain information through an afferent process. Little is known whether the encoding of external temperature stimuli differs between ethnic populations. Therefore, this research aimed to investigate ethnicity's influence on thermal perception between body-matched white British and Chinese participants and the extent to which physiological or psychological factors drive any variations observed. Four empirical studies were performed to investigate ethnic differences in local thermal sensation to warm (40°C) and cool (20°C) conductive stimuli (Chapter 3), the comparison between conductive and convective thermal stimuli on local thermal sensation (Chapter 4), ethnic differences in cutaneous thermal threshold detection (Chapter 5) and lastly, an exploration of ethnic differences in whole-body thermal perception at various relative humidities (Chapter 6). Several key themes emerged from the research: (1) No ethnic differences were found in the somatosensory response to warm and cool thermal stimuli. (2) Ethnic differences arise in the interpretation of 'hot' and 'cold' sensations. The Chinese group had a narrower inter-threshold range between hot and cold cutaneous sensations than the British group. (3) Minor ethnic differences were observed in whole-body perceptual data for thermal sensation and thermal comfort. However, when exposed to various relative humidity levels, significant differences emerged in perceptions of wetness and stickiness. (4) Conductive and convective thermal sensation measurements can vary significantly between a stimulus application time of 0 seconds (to provide an immediate response) and durations of 10, 30 and 60 seconds. Local skin temperature and thermal sensation stabilise at 30-s for the conductive response and 60-s for the convective. Across all studies, no significant differences were identified across most physiological measurements (e.g., forearm blood flow, resting metabolic rate, heart rate, tympanic temperature, or mean skin temperature), with minor differences observed in anthropometrics, skin thickness and skin hydration. Overall, the research assessed physiological and perceptual ethnic differences between white British and Chinese populations. The results show that both groups have the same somatosensory response to the thermal environment, yet the interpretation of the thermal information is likely shaped by non-physiological factors such as thermal history, experiences, and expectations.

Calcium antagonists are an important class of drugs for the treatment of hypertension, ischaemic heart disease and certain cardiac arrhythmias. Nifedipine is a dihydropyridine calcium antagonist and a substrate of CYP3A enzymes in humans. It undergoes extensive first-pass metabolism after oral administration. An interaction between nifedipine and grapefruit juice produced a significant increase in the area under the plasma concentration time curve (AUC) of nifedipine after oral but not intravenous dosing compared with control. Grapefruit components inhibit cytochrome P450 medicated oxidation of nifedipine to the nitropyridine metabolite and the site of grapefruit effect is possibly the first-pass metabolism in the intestine. Flavonoids of grapefruit juice are powerful in vitro inhibitors of CYP3A enzymes and quercetin is a commonly occurring flavonoid. An in vivo study with oral grapefruit juice and quercetin in healthy volunteers showed that unlike grapefruit juice, quercetin did not produce an increase in AUC of nifedipine compared with control. Therefore quercetin is not the cause of grapefruit juice mediated inhibition of nifedipine oxidation and can be excluded as an in vivo inhibitor of CYP3A. An oral plus intravenous comparison study between South Asians and Caucasians showed a two-fold increase in AUC and t/12 of nifedipine in South Asians who showed a significantly lower-systemic clearance compared to Caucasians but a similar bioavailability. This suggests a lower hepatic CYP3A activity in South Asians compared with Caucasians. A study of ethnic influence on the kinetics of nifedipine (20 mg oral dose) in 11 healthy Nigerians showed that Nigerians have a more than two-fold increase in AUC and t1/2 compared with Caucasians.

Hypertension, or high blood pressure, is a leading cause for mortality and morbidity worldwide. When split by ethnicity, African American (AA) individuals are at a greater risk for the development of hypertension compared to Caucasian American (CA) individuals. It is thought that over the course of hypertension, higher cardiac output is typically responsible for initially higher BP, and as hypertension progresses, cardiac output normalizes and total peripheral resistance (TPR) increases. Autonomic nervous system (ANS) activity is thought to underlie the development of hypertension, including the aforementioned hemodynamic changes. Ethnic differences have been found in resting ANS and hemodynamic activity, and are thought to potentially underlie ethnic disparities. Moreover, sex differences in resting ANS activity and the development of hypertension have been reported. One common theme underlying ethnic and sex differences in ANS control is vagally-mediated (vmHRV), which is widely recognized as an index of parasympathetic nervous system (PNS) activity, and serves as an independent risk factor for hypertension. However, research has yet to examine how ethnicity, sex, and vmHRV may interact to produce different patterns of hemodynamics in long-term BP regulation. In the following study, prospective methods were used to investigate this complex relationship. I investigated hemodynamic patterns over the course of six years, with physiological measures taken at two time points: (1) Baseline/initial visit (“Time 1”) and; (2) follow up visit on an average of 6 years later (“Time 2”). I considered hemodynamic patterns from “Time 1” to “Time 2” in the full sample, in addition to split by ethnicity (AAs and CAs), by sex (males and females), and vmHRV at “Time 1”. A median split was conducted on “Time 1” vmHRV to create high and low vmHRV groups to show the impact of relative high and low vmHRV on hemodynamics over time. Results showed that in normotensive individuals, CAs show a relative normal aging of the cardiovascular system over time, characterized by increased BP over time via increased cardiac output and stable or decreased TPR, a pattern seen especially in CA males with higher vmHRV. In contrast, AAs showed a more deleterious pattern of cardiovascular activity, marked by increased BP via increases in TPR, a pattern seen especially in AA females with lower vmHRV. Overall these data suggest a similar outcome of higher BP, however this is achieved via different hemodynamic mechanisms as a function of ethnicity, sex, and resting PNS activity as indexed by baseline vmHRV. Based on these factors, implications for psychophysiological function, in addition to the development and treatment of hypertension, will be discussed.

The proposed study aimed to identify ethnic differences in how witnessing parental violence, masculine gender role strain (MGRS), and anger disposition are associated with the perpetration of male-to-female intimate partner violence (IPV). A conditional process model to account for the intergenerational transmission of IPV through MGRS (mediator) is tested. A multicultural convenience sample of 225 Asian American, Latino American, and White men from a diverse university in southern California completed the online “Men’s Experiences Survey.” Results indicated that witnessing parental violence was a significant predictor of IPV in Asian men, but not among those of other ethnicities. Anger disposition was a significant predictor of IPV for Latino men, but not others when adjusting for covariates. No significant predictors emerged for the White sample. Anger disposition emerged as a significant moderator for the conditional process model of the intergenerational transmission of IPV, but no support was found for mediation in the model. Implications of the study’s findings, limitations related to measured levels of IPV in this sample, and future directions for similar lines of research are discussed.

Objective: The primary objective of this study was to examine the prevalence of chronic pelvic pain (CPP) amongst various ethnic groups in the state of Hawaiʻi. A second objective was a secondary analysis of the data to identify any factors that may increase the risk of chronic pelvic pain. Methods: From 2005-2006, the annual Hawaiʻi Health Survey was administered to residents of the state of Hawaiʻi, by a third party vendor contracted with the Hawaiʻi Department of Health, to households with landline phones. Survey data were gathered on 24,642 people in 8503 households statewide. Questions about pelvic pain were added to the annual Hawaii Health Survey. Non-pregnant women household responders, over the ages of 18, were surveyed to assess the 3 month cross-sectional prevalence of chronic pelvic pain. Chronic pelvic pain is defined as pain below the belly button or in the female organs for more than 6 months. Those who reported chronic pelvic pain were surveyed on severity, frequency, diagnosis, and treatment. The data were weighted to account for age, gender, island location, and ethnicity. Results: All data is reported weighted to represent the general population. The survey data were weighted to represent 957,540 household members, reflecting the general population of Hawaiʻi. Forty-nine percent were male and 51.1% were female. The mean age of non-pregnant female adult respondents was 49.7 years old (SD 18.0). Of the 488,833 adult women, 10,404 (2.1%) were pregnant and 477,996 (97.8%) were not pregnant. In the last 3 months, 34,210 (7.2%) of the non-pregnant adult women surveyed responded yes to having pelvic pain. Of these, 13,449 of women responded yes to having the pain for more than 6 months. The prevalence of chronic pelvic pain was 2.8%. The mean pain score was 5.95 out of 10 (SD 2.50). Most women were not given a diagnosis, but the most common pathological diagnosis cited was endometriosis (11.3%). Though most women 10,553 (79.9%) did not miss any work, 9.1% missed less than 5 days of work, and 10.7% missed from 5 days to more than 15 days of work due to pelvic pain the previous 3 months. Twenty percent (2,580) rated themselves as fully productive, but 21% rated themselves with very low productivity, when having pelvic pain. African-American/Black (10.4%), Hawaiian (5.0%), and Caucasian/white (3.4%) were the ethnicities with the highest prevalence of chronic pelvic pain. And Chinese (1.7%), Japanese (1.1%), Other (1.3%), Asian (0.6%), and Samoan (0.4%) were below the mean prevalence of CPP. Vietnamese, Other Pacific Islander, Korean, and Asian Indian had no primary respondents who had CPP. When adjusting for age, marital status, weight, and menopausal status, African Americans (332% increased risk) and Hawaiians (27.5% increased risk) had the highest increased risk of CPP compared to Caucasians. Being in an unmarried relationship or divorced increased a woman's risk of having CPP by 8% and 10%, respectively. Being menopausal had a variable impact on risk of CPP depending on other confounding factors, and educational status was not significant for CPP. Conclusions: Chronic pelvic pain has a lower rate of prevalence at 2.8% than found nationally. African Americans and Hawaiians are at a greater risk of having CPP in the state of Hawaii. CPP results in missed days from work and adversely impacts work productivity. Hawaiians appear to be at greater risk of using more health care resources when having CPP. Additional investigations are needed to develop management approaches for this health disparity.

Differences between Asian-heritage and European-heritage individuals have been found in both the prevalence and expression of social anxiety. Previous research suggests higher social anxiety among AH individuals, but both the methodology and the findings have been mixed and the effect sizes varied widely. The purpose of this meta-analytic study was to examine whether the AH/EH differences in social anxiety were robust across various moderators, and how these differences may be accounted by ethnic differences in self-construal and acculturative stress. The meta-analysis revealed a moderate mean effect size of d = 0.36, CI [0.27, 0.44]. Moderator analyses demonstrated that these effects were robust across moderators. Results of meta-regression analyses indicated that independent self-construal significantly contributed to social anxiety. Directions for future research include exploration of measurement issues, and a need to develop a theoretical model that includes factors that mediate the ethnic differences in independent self-construal and differences in social anxiety.

Cigarette smoking is a known risk factor for the development of lung cancer: approximately 1 out of 5 heavy smokers will develop the disease. However, there are significant differences in risk of lung cancer among smokers from different ethnic/racial groups. African American and Native Hawaiian smokers are at a higher risk of lung cancer than European American, Japanese American or Latin American smokers. Cigarette smoke has more than 70 known carcinogens. Following metabolic activation to electrophilic species, these carcinogens can form covalent DNA adducts, which are capable of inducing heritable mutations ultimately resulting in lung cancer. It has been hypothesized that the observed ethnic/racial differences in lung cancer risk in smokers are due to different frequencies of specific polymorphisms in drug metabolizing genes, leading to a different degree of carcinogen bioactivation to DNA-reactive intermediates. 1,3-Butadiene (BD) is among the most abundant and potent carcinogens present in cigarette smoke. BD is metabolically activated primarily by CYP2E1 to form 3,4-epoxy-1-butene (EB), hydroxymethyl vinylketone (HMVK), 3,4-epoxy-1,2-butanediol (EBD), and 1,2,3,4-diepoxybutane (DEB). EB, HMVK, EBD, and DEB have been shown to modify DNA bases to form promutagenic adducts. Alternatively, EB, EBD, and DEB can undergo detoxification via epoxide hydrolysis (the main pathway in humans) or glutathione conjugation and further metabolic conversion into urinary mercapturic acids, 1-hydroxy 2-(N-acetylcysteinyl)-3-butene (MHBMA), 1,2-dihydroxy-4-(N-acetyl cysteinyl)-butane (DHBMA), 1,2,3-trihydroxy-4-(N-acetylcysteinyl)-butane (THBMA), and 1,4-bis-(N-acetylcysteinyl)butane-2,3-diol (bis-BDMA), respectively. The research presented in this thesis focuses on revealing any ethnic/racial differences in metabolism of BD in smokers and examining the ability of BD-DNA adducts to cause mutations. In the first part of the thesis, we have identified two novel metabolites of BD which have not been previously detected in vivo: 1,2,3-trihydroxy-4-(N-acetylcysteinyl)-butane (THBMA), and 1,4-bis-(N-acetylcysteinyl)butane-2,3-diol (bis-BDMA). To enable their detection in smokers, sensitive and specific HPLC-ESI--MS/MS methods were developed for both metabolites in human urine. We observed significant amounts of THBMA in samples from smokers, non-smokers and occupationally exposed workers. In contrast, bis-BDMA amounts in urine of smokers and occupationally exposed workers were below the method's limit of detection, although it was found in urine of F344 rats exposed to 62.5 or 200 ppm BD. Additionally we found significant interspecies differences in BD metabolism between laboratory rats and humans. DHBMA accounted for only 47% of BD urinary mercapturic acids in rats while the corresponding percentage in humans is 93%. We further developed a high throughput HPLC-ESI--MS/MS method for the quantification of MHBMA and DHBMA in humans and applied this method to quantify urinary BD-mercapturic acids metabolites in workers from a BD and styrene butadiene rubber (SBR) manufacturing facility and smokers belonging to different ethnic groups in two separate multi-ethnic cohort studies. Workers occupationally exposed to BD excreted significantly more BD-mercapturic acids than administrative workers at the same plant. In a small multi-ethnic study of smokers belonging to European American, Native Hawaiian and Japanese American (N = 200 per group), mean urinary MHBMA and MHBMA/DHBMA+MHBMA metabolic ratio were highest in European American and lowest in Japanese American smokers. Similar results were obtained in the larger study (N = 450 per group) composed of European American and African American smokers. Urine of European American smokers contained higher concentrations of MHBMA than that of African Americans. Genome-wide association study (GWAS) analysis conducted for the larger multi-ethnic group has revealed significant associations between single-nucleotide polymorphisms (SNPs) in chromosome 22 (22564172bp - 22735492 bp, nearby genes GSTT1, GSTT2, DDT and MIF) and urinary BD-mercapturic acid levels in smokers, providing the first evidence for genetic and ethnic/racial differences in metabolism of BD.The second part of my thesis work has focused on evaluating the mutagenic ability of three recently discovered BD-dA lesions: N6-(2-hydroxy-3-buten-1-yl)-adenine (N6-HB-dA), N6,N6-(2,3-dihydroxybutan-1,4-diyl)-2'-deoxyadenosine (N6,N6-DHB-dA), and 1,N6-(2-hydroxy-3-hydroxymethylpropan-1,3-diyl)-2'-deoxyadenosine (1,N6-&gamma-HMHP-dA). In vitro translesion synthesis experiments were performed on synthetic oligonucleotides containing each of the three lesions at a site-specific position by gel electrophoresis and HPLC-MS/MS. We found that human translesion synthesis (TLS) polymerases hPols &eta, &kappa, &iota and human polymerase &beta were able to bypass (S)-N6-HB-dA in an error-free manner because of the conserved Watson-Crick base pairing with dT. However, replication past both (R,R)-N6,N6-DHB-dA and (R,S)-1,N6-&gamma-HMHP-dA lesions by TLS polymerases hPols &eta and &kappa was highly error-prone, resulting in A&rarrT, A&rarrC mutations and frameshift deletions. This is the first study that identifies (R,R)-N6,N6-DHB-dA and (R,S)-1,N6-&gamma-HMHP-dA as BD-DNA adducts potentially responsible for the induction of A*rarrT mutations by BD.

Abstract: Research suggests that visible ethnic minority parents engage in cultural socialization practices and that visible ethnic minority children experience peer ethnic victimization more often than ethnic majority Caucasian children. Limited research has assessed ethnic differences in the construct validity and psychometric properties of measures assessing parent cultural socialization practices and peer ethnic victimization. This study examines ethnic differences in the construct validity and psychometric properties (reliabilities, mean levels) of these measures and in the associations between these constructs. Participants included 439 kindergarten to third-grade children and 275 of their parents from diverse ethnic groups. The constructs showed adequate construct validity across the overall visible ethnic minority and ethnic majority Caucasian groups. However, reliability was low at some waves for some ethnic groups. Relative to other ethnic groups, Southeast/East and West/South Asian parents engaged in more frequent cultural socialization practices and Black/African Canadian children experienced higher levels of peer ethnic victimization.

There is a dearth of research focusing on fathering in families of color. The present study argues that ecological factors, especially SES and neighborhood quality, exert a strong influence on racial and ethnic differences in fathering role identity, which in turn affect fathering role performance. The primary goal of the present study is thus to investigate the impact of ecological factors on what it means to be a good father among African American (n = 308), Latino American (n = 598), Asian American (n = 580), and white fathers (n = 2813) by using a nationally representative sample from the Early Childhood Longitudinal Study, Birth Cohort (ECLS-B), and to test identity theory by examining fathering identity as a primary determinant of fathering role performance. The core premise of identity theory is that society is the main source in shaping self (i.e., identity), and in turn, contributes to the way people behave (Stryker, 1968). The present study tested identity theory by examining the associations between domain-level psychological centralities and domain-specific fathering performances, and also to test whether effects of psychological centralities and contextual factors override those of race and ethnicity. Overall, the results from this study considerably buttressed identity theory. Consistent with the cultural-ecological model (Ogbu, 1981), which posits that ecological conditions shapes culture-specific socialization goals, racial and ethnic differences in the fathering psychological centrality were found because fathers in the same group historically share similar circumstances. However, the heterogeneity of the psychological centrality within each group was remarkable because their current conditions are vastly multifarious. Specifically, the lower their SES, the more likely that they believe that providing for their children is central to their identity as a father. In studying fathers of color, previous approaches often resulted in the unwitting spread of stereotypical images by contrasting minority fathers from at-risk population with middle-class white fathers, because such approaches failed to consider the effects of contextual factors on fathering and to include multiple forms of father involvement. The results from this study clearly show that racial and ethnic differences are subtle once contextual factors are taken into account.

Prior research regarding the validity of the self-rated health question has presented data suggesting ethnicity is a barrier when comparing respondent understanding of the self-rated health question. If it can be shown that ethnic minority respondents have an unrecognized understanding of the self-rated health question that would hint at the subjective question being an unreliable measure of health for all ethnic populations. The Jacobson (2004) study was designed to explore this possibility, performing cognitive interviews with a sample (n=74) of diverse ethnic respondents. Respondents were asked the self-rated health question and cognitive questions probing their understanding of the SF-36 questionnaire. The investigation performed in this study was based off analysis of data collected in the 2004 study. This study analyzed responses to the self-rated health question and coded responses to three cognitive questions. Findings suggested ethnic minorities and non-minorities understand the self-rated health question in different manners.

Ethnic differences in etiological factors linked to body image dissatisfaction and eating disorders were examined. In addition, the interaction of acculturation and body image dissatisfaction in influencing minority women's relationships with their parents was investigated. Participants consisted of 302 undergraduates from three ethnic groups: Caucasian, Hispanic American, and African American women who were administered self-report measures. Differences were not found between the groups in body image dissatisfaction. Low self-esteem, internalization of the thin ideal, and family emphasis on weight and appearance were all related to more body image dissatisfaction for each of these groups; however, differences in degree of endorsement were also noted between the ethnic groups on these factors. Based on the interaction findings (body image x acculturation) separation from one's mother was found in the area of attitudes and emotions for the Hispanic sample but not for the African American sample on any of the parent scales. Areas for future research and implications for diagnosis and treatment of minority populations are also discussed.

Core features of autism spectrum disorder (ASD) were examined from different perspectives. In the first study, children with ASD were compared to children with fetal alcohol spectrum disorder (FASD) in order to isolate social deficits that are most unique to ASD. Difficulties in initiating social interaction, sharing affect, and using nonverbal communication were common in children with ASD but rare in children with FASD. Socially inappropriate behaviors and difficulty with peers were common in children with ASD and children with FASD. These findings suggest that whereas propensity for social interaction may be a differentiating factor between children with ASD and those with non-spectrum disorders, social appropriateness may be less diagnostically discriminative. In the second study, the relationship between restricted and repetitive behaviors (RRBs) and nonverbal IQ (NVIQ) was examined in a large group of children with ASD. RRBs were prevalent in children with ASD of different levels of functioning, but certain behaviors were more common either in lower or higher functioning children. These results lend some support to the idea of different classes of RRBs. Whereas sensory-motor RRBs were related to age and NVIQ, insistence on sameness RRBs were less clearly related to developmental level. Additionally, there was an interactive effect of NVIQ and chronological age on the presence of RRBs; lower NVIQ was more closely associated with a higher prevalence of certain RRBs in older children than in younger children. In the third study, mothers of 9-year-old children with ASD completed interviews about the perceived negative impact of having a child with ASD. Several parent, child, and family variables were examined as potential predictors of perceived negative impact. African American mothers reported significantly lower levels of perceived negative impact than Caucasian mothers. Mothers of children with lower adaptive behavior scores and more RRBs also reported higher perceived negative impact, as did mothers who reported having little or no social support.