Unique and interactive roles of economic stress and discrimination on heterogeneous development among Chinese American adolescents: An 8-year longitudinal study.

Chinese American youth as a group are often labeled as "model minorities." Yet, this label ignores the vast heterogeneity within Chinese Americans and implies that they are immune to environmental stressors. Using an 8-year longitudinal study of 444 (54% female; initial Mage = 13-year-old) Chinese American adolescents, we identified two (well- vs. poorly adjusted) concurrent and three (stably well-adjusted, improved, and risk) latent transition profiles from early adolescence to emerging adulthood based on six indicators of academic, behavioral, and socioemotional functioning. Multilevel modeling revealed higher levels of family economic stress or discrimination independently associated with higher likelihood to be in the subgroup of adolescents with poorly adjusted patterns across development. Within an individual, Chinese American adolescents were more likely to have worse adjustment patterns in the year when they experienced higher economic stress or discrimination relative to other study years, suggesting that their adjustment are sensitive to the fluctuation of stress level during development. Longitudinally, those who experienced higher family economic stress or discrimination at early adolescence were more likely to become at risk when they reached adulthood. Higher discrimination predicted the likelihood to be in the improved groups but only among adolescents with low (but not high) economic stress, suggesting that the influence of discrimination may vary by family socioeconomic status. Findings (a) challenge the model minorities assumption, (b) highlight the importance of capturing multiple ecological contexts associated with heterogeneous development among Chinese American adolescents, and (c) provide longitudinal evidence to social policies aiming to reduce wealth disparities and anti-Asian racism. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

Daily and Ethnic Discriminatory Experiences and Cognitive Control in Mexican-Origin Bilingual Language Brokers.

Few studies have considered bilingualism's impact on cognitive development within the sociolinguistic and cultural context of the immigrant communities where bilingualism is commonly practiced. In the United States, many Mexican-origin bilingual youth practice their bilingual skills by brokering (i.e., translating/interpreting between languages) for their immigrant parents who have low English proficiency. Meanwhile, these youth may also experience discrimination in their daily life. The present study focuses on Mexican-origin bilingual youth brokers (N=334) in order to examine how discriminatory experiences (i.e., daily and ethnic discrimination) and bilingual brokering experiences captured by profiles are related to cognitive control performance (i.e., attentional control and inhibition). We found no significant direct influence of either bilingual broker profiles or discriminatory experiences on cognitive control. However, the associations between discriminatory experiences and cognitive control performance depended upon brokering experiences. Specifically, greater discrimination was associated with lower cognitive control performance among moderate brokers (with moderate bilingual experiences), but the association was attenuated among efficacious brokers (with positive bilingual experiences). Findings highlight the need to consider the sociolinguistic heterogeneity of both discriminatory experiences and language use when investigating cognitive control performance in bilinguals.

Understanding adjustment profiles among Mexican-origin adolescents over time: A focus on cultural risk and resilience factors.

This study used a three-wave longitudinal dataset to: identify adjustment profiles of U.S. Mexican-origin adolescents based on their physical, academic, and psychosocial health adjustment; track adjustment profile changes throughout adolescence; and examine the associations between cultural stressors, family obligation, and adjustment profile membership over time. Participants were 604 Mexican-origin adolescents (54% female, Mage = 12.41, SD = 0.97) in Texas (Wave 1: 2012-2015; Wave 2: 2013-2016; Wave 3: 2017-2020). Three concurrent profiles (Well-adjusted, Moderate, and Poorly-adjusted) emerged at each wave, whereas three transition profiles (Improved, Stable well-adjusted, and Overall poorly-adjusted) were identified across three waves. The results suggest that cultural stressors pose risks for Mexican-origin adolescents' adjustment, and family obligation values play a protective role in these associations.

Mexican-origin adolescents' cumulative strengths predict baseline and longitudinal changes in self-growth outcomes.

This study adopts a cultural ecological perspective to examine how cumulative effects of external transcultural and cultural strengths are related to baseline and changes in three markers of Mexican-origin adolescents' self-growth (i.e., resilience, life meaning, and discipline). Using a three-wave longitudinal data set (5 years) of 604 adolescents, cumulative strengths (CS) was calculated, and growth curve analyses showed a similar pattern of findings for both transcultural and cultural cumulative strengths models: Adolescents with higher CS showed higher baseline resilience, life meaning, and discipline. While there were no significant associations between adolescents' CS scores and the increase in resilience, adolescents with higher CS scores showed steeper declines in life meaning and discipline (although these declines were no longer significant for cultural CS when transcultural and cultural CS were simultaneously tested in the same model). The findings emphasize a cultural ecological understanding of Mexican-origin youths' positive development from early to later adolescence. They also provide support for a CS model and have implications for positive psychology theories. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

Language brokering profiles of Mexican-origin adolescents in immigrant communities: Social-cultural contributors and developmental outcomes.

This study examines social-cultural contributors and developmental outcomes of language brokers. From 2012 to 2020, three waves of data were collected from 604 Mexican-origin adolescent language brokers (Mage = 12.92, SD = 0.92, 54% girls). The study (1) identified four distinct subgroups of language brokers (efficacious, conservative, nonchalant, and burdened) who translated for mothers and fathers, after incorporating objective bilingual proficiency along with multiple dimensions of language brokering; (2) showed that early adolescents' Mexican, rather than U.S., cultural values and orientation were related to later language brokering profiles; and (3) showed that the efficacious group was the most resilient while burdened was the most vulnerable to developmental problems. Preservation of Mexican culture may facilitate language brokering experiences related to more positive developmental outcomes.

Core taxa, co-occurrence pattern, diversity, and metabolic pathways contributing to robust anaerobic biodegradation of chlorophenol.

It is hard to achieve robustness in anaerobic biodegradation of trichlorophenol (TCP). We hypothesized that specific combinations of environmental factors determine phylogenetic diversity and play important roles in the decomposition and stability of TCP-biodegrading bacteria. The anaerobic bioreactor was operated at 35 °C (H condition) or 30 °C (L condition) and mainly fed with TCP (from 28 µM to 180 µM) and organic material. Metagenome sequencing was combined with 16S rRNA gene amplicon sequencing for the microbial community analysis. The results exhibited that the property of robustness occurred in specific conditions. The corresponding co-occurrence and diversity patterns suggest high collectivization, degree and evenness for robust communities. Two types of core functional taxa were recognized: dechlorinators (unclassified Anaerolineae, Thermanaerothrix and Desulfovibrio) and ring-opening members (unclassified Proteobacteria, Methanosarcina, Methanoperedens, and Rubrobacter). The deterministic process of the expansion of niche of syntrophic bacteria at higher temperatures was confirmed. The reductive and hydrolytic dechlorination mechanisms jointly lead to C-Cl bond cleavage. H ultimately adapted to the stress of high TCP loading, with more abundant ring-opening enzyme (EC 3.1.1.45, ∼55%) and hydrolytic dechlorinase (EC 3.8.1.5, 26.5%) genes than L (∼47%, 10.5%). The functional structure (based on KEGG) in H was highly stable despite the high loading of TCP (up to 60 µM), but not in L. Furthermore, an unknown taxon with multiple functions (dechlorinating and ring-opening) was found based on genetic sequencing; its functional contribution of EC 3.8.1.5 in H (26.5%) was higher than that in L (10.5%), and it possessed a new metabolic pathway for biodegradation of halogenated aromatic compounds. This new finding is supplementary to the robust mechanisms underlying organic chlorine biodegradation, which can be used to support the engineering, regulation, and design of synthetic microbiomes.

Reconsidering the "Acculturation Gap": Mother-Adolescent Cultural Adaptation Mis/Matches and Positive Psychosocial Outcomes among Mexican-Origin Families.

Previous studies have linked parent-child cultural adaptation mismatches with adolescents' maladjustment without addressing how intergenerational mis/matches are related to positive aspects of adolescent development and parental outcomes. Using data from 604 Mexican-origin families (adolescent sample:54%female, Mage = 12.41, range = 11 to 15), response surface analysis was conducted to investigate how mother-child mis/matches in cultural adaptation (acculturation, enculturation, English and Spanish proficiency) are associated with adolescents' and mothers' resilience and life meaning. Adolescents and mothers reported greater resilience and meaning when they matched at higher, versus lower, levels of acculturation, enculturation and English proficiency; adolescents reported more resilience when they were more acculturated than mothers. The findings provide a strengths-based understanding of parent-child cultural adaptation mis/matches and elucidate how Mexican-origin families thrive in the cultural adaptation process.

Mexican-origin youths' language brokering for fathers and mothers: Daily experiences and youths' diurnal cortisol slopes.

This study examined the associations of language brokering stress intensity and exposure with Mexican-origin youths' cortisol responses when brokering for fathers and mothers, and the moderating role of youths' brokering efficacy in these relations. Participants were 289 adolescents (Mage  = 17.38, SD = .94, 52% girls) in immigrant families. When brokering for mothers, stress exposure was related to flatter (less healthy) same-day diurnal slopes in youth. When brokering for fathers, daily brokering efficacy buffered the detrimental link between stress intensity and youths' same-day cortisol slopes. When brokering for fathers/mothers, stress intensity and exposure were related to flatter (less healthy) next-day diurnal slopes. Although daily brokering stress can relate to youth physiologic functioning, feeling efficacious about brokering may buffer the negative ramifications of stress.

Do Mothers' Experiences Count? An Actor-Partner Interdependence Model of Language Brokering Experiences in Mexican Immigrant Families.

Language brokering is a shared parent-child experience with implications for parent-child relationships and, in turn, individuals' psychological well-being; however, few studies recognize the role of parents. This study took a dyadic approach to investigate the association between brokering experiences and internalizing symptoms, and the mediating role of parent-child alienation. Participants were 604 Mexican-origin adolescents (54% female, Mage = 12.41) and their mothers (N = 595). Both adolescents' and their mothers' brokering experiences were related to their own internalizing symptoms via their self-reported parent-child alienation. Mothers' brokering experiences also affected adolescents so that when mothers experienced more negative brokering experiences, adolescents perceived greater parent-child alienation, and in turn more internalizing symptoms, suggesting the necessity of considering language brokering's influence on members involved as a dyadic process.

Pathways linking ethnic discrimination and drug-using peer affiliation to underage drinking status among Mexican-origin adolescents.

Using a three-wave longitudinal data set of Mexican-origin adolescents (N = 602, Mage = 12.92, SD = 0.91 at Wave 1), this study examines parallel pathways from early exposure to ethnic discrimination and drug-using peers, separately, to underage drinking status by late adolescence. Negative affect was expected to mediate the link from ethnic discrimination to underage drinking status (the stress-induced pathway), whereas social alcohol expectancy was expected to mediate the link from drug-using peers to underage drinking status (the socialization pathway). Our findings lend support to the stress-induced pathway while controlling for the socialization pathway. For the stress-induced pathway, we found that early ethnic discrimination experiences were related to higher likelihood of having engaged in underage drinking by late adolescence through elevated negative affect sustained across adolescence. For the socialization pathway, we found no association between affiliation with drug-using peers in early adolescence and underage drinking status, either directly or indirectly. Present findings highlight the unique role of early ethnic discrimination experiences in underage drinking among Mexican-origin adolescents, over and above the effect of drug-using peers. Alcohol use interventions targeting ethnic minority adolescents should account for adolescents' ethnic discrimination experiences by helping adolescents develop adaptive coping strategies to handle negative affect induced by discrimination (e.g., reappraisal) rather than using alcohol to self-medicate. (PsycInfo Database Record (c) 2022 APA, all rights reserved).

Culturally relevant stressors as moderators of intergenerational transmission of mother-adolescent executive function in Mexican immigrant families.

The intergenerational transmission of executive function may be enhanced or interrupted by culturally salient environmental stressors that shape the practice of executive function in the family. Building upon past research, the current study tests whether culturally relevant stressors such as economic stress and foreigner stress have a direct effect on adolescent executive function, as well as whether they modify the intergenerational transmission of mother-child executive function (i.e., working memory, inhibitory control, and shifting) in low-income Mexican immigrant families. The sample consists of 179 Mexican American adolescents (Mage = 17.03 years; SDage = 0.83; 58% females) and their Mexico-born mothers (Mage = 43.25 years; SDage = 5.90). Results show that mothers' perceived economic stress is associated with poor inhibitory control in adolescents. Low levels of mothers' perceived foreigner stress related to a stronger association between mothers' and adolescents' working memory, while high levels of mothers' perceived foreigner stress related to enhanced intergenerational transmission of poor shifting ability. Study findings demonstrate the prominence of perceived foreigner stress as a contextually relevant factor moderating the intergenerational transmission of mother-child executive function in low-income Mexican immigrant families.

Language Brokering-Stress Transition Profiles and Marijuana Use in Mexican-Origin Adolescents.

Although Mexican-origin adolescents experience multiple contextual stressors (e.g., discrimination, economic stress, and foreigner stress) that may result in increased marijuana use, they actively engage in cultural practices (e.g., language brokering) that may protect them from adverse developmental outcomes. Yet, the joint influence of contextual stressors and language brokering on marijuana use has rarely been studied from a developmental perspective. Using a sample of 604 Mexican-origin adolescent brokers (54% female, Mage.Wave1 = 12.41), we examined how stability and change of language brokering-contextual stress (i.e., broker-stress) profiles across three waves are related to adolescent marijuana use. We hypothesized that adolescents with positive brokering experiences and lower contextual stress across three waves (i.e., those in the Stable Protective profile) would be the least likely to use marijuana. For brokering for mothers, the Stable Protective and the Change to Protective groups were less likely than other groups to use marijuana. For brokering for fathers, the Stable Protective group was the least likely to use marijuana and the Change to Protective group was less likely than the Risk at Any Wave group to use marijuana. Interventions could foster brokering-related positive feelings across the course of adolescence to reduce marijuana use among Mexican-origin adolescents.

Bilingual language broker profiles and academic competence in Mexican-origin adolescents.

We advance a tripartite framework of language use to encompass language skills, the practice of language skills, and the subjective experiences associated with language use among Mexican-origin adolescents who function as language brokers by translating and interpreting for their English-limited parents. Using data collected over 2 waves from a sample of 604 adolescents (Wave 1: Mage = 12.41, SD = 0.97), this study identified 4 types of bilingual language broker profiles that capture the tripartite framework of language use: efficacious, moderate, ambivalent, and nonchalant. All 4 profiles emerged across waves and brokering recipients (i.e., mothers, fathers), except for Wave 1 brokering for mother, in which case only 3 profiles (i.e., efficacious, moderate, and ambivalent) emerged. Three profiles emerged across time: stable efficacious, stable moderate, and other. The efficacious and stable efficacious profiles showed the most consistent relation to adolescents' academic competence. Improving bilingual language proficiency, together with fostering more frequently positive brokering experiences, may be an avenue to improving academic competence among Mexican-origin adolescents in the United States. (PsycInfo Database Record (c) 2020 APA, all rights reserved).

Characteristics of organic pollutants in source water and purification evaluations in drinking water treatment plants.

The release of contaminants of emerging concern (CECs) into water bodies has aroused wide concern in recent years. Little information on the characteristics of CECs to pose potential risks even at low concentrations in urban water systems of Shanghai is available. This study investigated the occurrence and spatial distribution in source water, as well as the fates by drinking water treatment processes for organic compounds including 35 pesticides, 17 antibiotics, 7 microcystins (MCs), and 10 disinfection by-products (DBPs). The similar trends across seasons for COD and TOC, the indicators for organic pollutants, indicated that the water qualities in three targeted reservoirs were relatively stable. COD in the R3 reservoir inlet was 1.3-2.4 times greater than that in the R1 and R2 reservoirs, possibly resulting from the inflow of the Taipu River as a tributary. Pesticides, particularly methamidophos and metabolites, macrolide and sulfonamide antibiotics, particularly roxithromycin, were frequently detected in Shanghai source water inlets. Pesticide concentrations were 2.58-3.66 µg/L much higher than antibiotics (8.6-47.6 ng/L). The results showed that MCs (ng/L) and DBPs (haloacetic acids, HAAs µg/L; N-nitrosodimethylamine, NDMA ng/L) were found to be in low detection frequencies. It was found that 51.1-74.6% of organic matters in source water were composed of molecular weight (MW) <1 kDa. The removal rates for the part of MW <1 kDa were only 11.7-12.3% through the conventional treatment processes, compared with higher removal rates of 23.5-28.5% by advanced treatment processes. Pesticides, antibiotics and MCs can be significantly removed by six drinking water treatment plants.

The microbial community responsible for dechlorination and benzene ring opening during anaerobic degradation of 2,4,6­trichlorophenol.

This study describes the dechlorination ability of acclimated biomass, the high-throughput sequencing of the 16S ribosomal RNA (rRNA) gene of such microorganisms, and the analysis of their community structure in relation to special functions. Two types of acclimated biomass (AB-1 and AB-2) were obtained via different acclimated treatment processes and were used to degrade 2,4,6­trichlorophenol. The degradation pathway and characteristics of trichlorophenol degradation were different between the two groups. AB-1 degraded trichlorophenol only to 4-chlorophenol. AB-2 completely dechlorinated trichlorophenol and opened the benzene ring. The 16S rRNA high-throughput sequencing method was employed to examine the microbial diversity. It was found that the microbial richness and diversity of AB-1 were higher than those of AB-2. Firmicutes and Bacteroidetes were 2.7-fold and 4.3-fold more abundant, respectively, in AB-1 than in AB-2. Dechlorination bacteria in AB-1 mainly included Desulfobulbus, Desulfovibrio, Dechloromonas, and Geobacter. The above-mentioned bacteria were less abundant in AB-2, but the abundance of Desulfomicrobium was twofold higher in AB-2 than in AB-1. The two types of acclimated biomass contained different hydrogen (H2)-producing bacteria. AB-2 showed higher abundance and diversity of hydrogen-producing bacteria. There was no Ignavibacteriae in AB-1, whereas its abundance in AB-2 was 8.4%. In this biomass, Ignavibacteriae was responsible for opening of the benzene ring. This study indicates that the abundance and diversity of microorganisms are not necessarily beneficial to the formation of a functional dechlorinating community. The H2-producing bacteria (which showed greater abundance and diversity) and Ignavibacterium were assumed to be core functional populations that gave AB-2 stronger dechlorination and phenol-degradation abilities. Control of lower oxidation reduction potential (Eh) and higher temperatures by means of fresh aerobic activated sludge as the starting microbial group, caused rapid complete dechlorination of 2,4,6­trichlorophenol and benzene ring opening.

Profiles of Language Brokering Experiences and Contextual Stressors: Implications for Adolescent Outcomes in Mexican Immigrant Families.

Adolescents from Mexican immigrant families are often embedded in a challenging social environment and experience multiple contextual stressors, including economic stress, discrimination, and foreigner stress. We consider how the effects of these contextual stressors may be amplified or diminished for adolescents who function as language brokers, interpreting and mediating for their English-limited parents. Using two waves of survey data collected from a sample (N = 604 at Wave 1; N = 483 at Wave 2) of Mexican American adolescents with ages ranging from 11 to 15 (Mage = 12.41, 54% female), four distinct brokering-stress profiles were identified. Latent profile analyses revealed that with moderate levels of contextual stress, adolescents with more positive language brokering experiences (protective group) demonstrated more favorable outcomes than those with neutral language brokering experiences (moderate group) and those who did not involve themselves as frequently in language brokering activities (less-involved group). In contrast, high levels of contextual stress, coupled with more negative language brokering experiences (risk group), produced the least favorable outcomes among adolescents.

UV photolysis for enhanced phenol biodegradation in the presence of 2,4,6-trichlorophenol (TCP).

A bacterial strain isolated from activated sludge and identified as Bacillus amyloliquefaciens could biodegrade phenol, but 2,4,6-trichlorophenol (TCP) inhibited phenol biodegradation and biomass growth. UV photolysis converted TCP into dichlorocatechol, monochlorophenol, and dichlorophenol, and this relieved inhibition by TCP. Phenol-removal and biomass-growth rates were significantly accelerated after UV photolysis: the monod maximum specific growth rate (µ(max)) increased by 9% after TCP photolysis, and the half-maximum-rate concentration (K(S)) decreased by 36%. Thus, the major benefit of UV photolysis in this case was to transform TCP into a set of much-less-inhibitory products.

Coupling UV-H2O2 to accelerate dimethyl phthalate (DMP) biodegradation and oxidation.

Dimethyl phthalate (DMP), an important industrial raw material, is an endocrine disruptor of concern for human and environmental health. DMP exhibits slow biodegradation, and its coupled treatment by means of advanced oxidation may enhance its biotransformation and mineralization. We evaluated two ways of coupling UV-H2O2 advanced oxidation to biodegradation: sequential coupling and intimate coupling in an internal circulation baffled biofilm reactor (ICBBR). During sequential coupling, UV-H2O2 pretreatment generated carboxylic acids that depressed the pH, and subsequent biodegradation generated phthalic acid; both factors inhibited DMP biodegradation. During intimately coupled UV-H2O2 with biodegradation, carboxylic acids and phthalic acid (PA) did not accumulate, and the biodegradation rate was 13 % faster than with biodegradation alone and 78 % faster than with biodegradation after UV-H2O2 pretreatment. Similarly, DMP oxidation with intimate coupling increased by 5 and 39 %, respectively, compared with biodegradation alone and sequential coupling. The enhancement effects during intimate coupling can be attributed to the rapid catabolism of carboxylic acids, which generated intracellular electron carriers that directly accelerated di-oxygenation of PA and relieved the inhibition effect of PA and low pH. Thus, intimate coupling optimized the impacts of energy input from UV irradiation used together with biodegradation.

[2, 4, 6-Trichlorophenol Mineralization Promoted by Anaerobic Reductive Dechlorination of Acclimated Sludge and Extracellular Respiration Dechlorination Pathway].

In anaerobic conditions, the acclimation of activated sludge was studied with sodium lactate as the electron donor and 2,4,6-trichlorophenol as the electron acceptor. Metabolic characteristics of dechlorination were the focus of this study. The result showed highly efficient dechlorination on 2, 4, 6-trichlorophenol that the conversion rate reached to 100% in 9 - 24 h when initial concentrations of sodium lactate and 2,4, 6-trichlorophenol were 20 mmol x L(-1) and 40 - 80 µmol x L(-1), respectively. The intermediate product 2,4-dichlorophenol was found in low concentration (< 4.22 µmol x L(-1)). And 4-chlorophenol and phenol were the main products. Ortho chlorophenol (2, 4, 6-trichlorophenol, 2, 4-dichlorophenol) can be converted rapidly by acclimated sludge, while the further conversion of 4-chlorophenol and phenol was limited. The residues of anaerobic metabolism were degraded by aerobic sludge, among which 4-chlorophenol (initial concentration of 33 mol x L(-1)) removal rate was up to 100% under aerobic conditions. The acclimated bacteria can rapidly transfer Fe(III) and humus (AQDS) into reductive Fe(II) and AQH2DS which indicated that the dissimilatory iron reducing bacteria was enriched in the acclimated sludge. The electron mediator [Fe(III) and AQDS] significantly accelerated the dechlorination rate. The acclimated sludge could perform extracellular respiration dechlorination with electron mediators.

Effects of pH and ORP on microbial ecology and kinetics for hydrogen production in continuously dark fermentation.

The microbial structure and kinetic characteristics of the hydrogen producing strains in two fermentative continuous stirred-tank reactors (CSTRs) were studied by controlling pH and oxidation and reduction potential (ORP). The fluorescence in situ hybridization (FISH) tests were conducted to investigate the fermentative performance of Clostridium histolyticum (C. histolyticum), Clostridium lituseburense (C. lituseburense) and Enterobacteriaceae. The experimental results showed that in ethanol-type reactor 1#, the relative abundance of the strains was 48%, 30% and 22%. Comparatively, the relative abundance in butyric acid-type reactor 2# was 24%, 55% and 19% with butyric acids and hydrogen as the main products. The kinetic results indicated that the hydrogen yield coefficients YP/X in both reactors were 8.357 and 5.951 l-H2/g, while the coefficients of the cellular yield were 0.0268 and 0.0350 g-Cell/g, respectively. At the same biomass, the hydrogen yield in ethanol-type reactors was more than that in butyric acid reactors. However, the cellular synthesis rate in ethanol-type reactors was low when the same carbon source was used.