Patterns of ethnic-racial identity and critical consciousness and associations with science, technology, engineering, and math engagement and perceived barriers: A latent class analysis of youth of color.

OBJECTIVES: Despite the well-documented scholarship highlighting ethnic-racial identity (ERI) and critical consciousness (CC) as promotive of positive academic outcomes, little research has explored what role these cultural assets may play in shaping science, technology, engineering, and math (STEM) engagement and perceptions of barriers to STEM for youth of color. This work explored relations between racially minoritized youths' patterns of ERI and CC in association with STEM engagement and perceptions of STEM career and educational barriers. METHOD: Latent class analysis and analysis of variance were used with a predominately Black and Latinx sample (N = 265, Mage = 15.83, SD = 1.35; 49% female). RESULTS: Four classes emerged. Members of the naïve affirmed advocates class had significantly higher STEM engagement than the disillusioned class. Youth in the affirmed and critical class reported the highest perceptions of STEM-related career barriers, followed by the affirmed advocates class. CONCLUSIONS: Findings highlight the critical link between ERI and CC as promotive factors for academic engagement for racially minoritized youth in STEM and promote awareness of STEM-related barriers that may be useful to prepare and navigate future STEM challenges. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

CowN sustains nitrogenase turnover in the presence of the inhibitor carbon monoxide.

Nitrogenase is the only enzyme capable of catalyzing nitrogen fixation, the reduction of dinitrogen gas (N2) to ammonia (NH3). Nitrogenase is tightly inhibited by the environmental gas carbon monoxide (CO). Nitrogen-fixing bacteria rely on the protein CowN to grow in the presence of CO. However, the mechanism by which CowN operates is unknown. Here, we present the biochemical characterization of CowN and examine how CowN protects nitrogenase from CO. We determine that CowN interacts directly with nitrogenase and that CowN protection observes hyperbolic kinetics with respect to CowN concentration. At a CO concentration of 0.001 atm, CowN restores nearly full nitrogenase activity. Our results further indicate that CowN's protection mechanism involves decreasing the binding affinity of CO to nitrogenase's active site approximately tenfold without interrupting substrate turnover. Taken together, our work suggests CowN is an important auxiliary protein in nitrogen fixation that engenders CO tolerance to nitrogenase.

Ethnic Socialization, Family Cohesion, and Ethnic Identity Development Over Time among Latinx Adolescents.

Family socialization of one's ethnic culture is essential for ethnic identity development among Latinx adolescents. However, less is known about how the likely changes in family interaction that transpire during adolescence may impact this socialization process. A three-year longitudinal study of 148 Latinx adolescents (ages 13-14; 53% females) examined how changes in youth's family ethnic socialization experiences and sense of family cohesion were related to two dimensions of their ethnic identity development (i.e., exploration and resolution). Youth's family ethnic socialization experiences and sense of family cohesion remained stable, while their exploration and resolution increased across three years. More ethnic socialization experiences at Wave 1 predicted higher initial levels and stability of ethnic identity exploration over time. However, more ethnic socialization at Wave 1 predicted higher initial levels of resolution and predicted less resolution development as youth progressed through adolescence. Among youth who perceived less ethnic socialization, a greater sense of family cohesion was associated with more initial exploration; this compensatory effect was only present at Wave 1. These results illustrate how distinct aspects of the family context uniquely and interactively inform ethnic identity exploration and resolution development.

Intergroup Contact Attitudes Across Peer Networks in School: Selection, Influence, and Implications for Cross-Group Friendships.

This study offers new insights into the power of peer networks for shaping intergroup relations in a diverse school. Data were drawn from a longitudinal study of sixth-eighth graders (N = 524; MageT1  = 11.87; 48% girls; 9% Asian American/Pacific Islander, 28% African American, 13% Latino, 1% Native American, 31% White, 5% Other, and 11% Multiracial) in the Midwestern United States. Students with more positive intergroup contact attitudes (ICA) were most likely to be friends with similarly minded students. Students with more positive ICA were less likely to select friends of the same race/ethnicity than those with less positive ICA. Finally, students' ICA became more similar to their friends' ICA over time. Results implicate school-level norms and contagion in students' ICA.

Ethnic-Racial Identity and Friendships in Early Adolescence.

The current study examined how adolescents' ethnic-racial identity (ERI) informed the demographic diversity of their friendship network (Goal 1) and the extent of similarity between adolescents' and their friends' ERI (Goal 2). Participants were sixth and seventh grade students (N = 353; Mage  = 11.88, SD = .73; 50% girls; 29% African American, 31% White, 13% Latino) in the Midwestern U.S. Results from longitudinal cross-lagged models (Goal 1) indicated that having more diverse friendships at T2 was associated with greater T3 ERI exploration among all youth. In addition, boys who reported higher ERI resolution at T1 had more diverse friendships at T2. Furthermore, findings from longitudinal social network analyses (SNA; Goal 2) suggested that influence drove similarity between adolescents and their friends in ERI exploration and resolution.

Heterologous expression and characterization of the manganese-oxidizing protein from Erythrobacter sp. strain SD21.

The manganese (Mn)-oxidizing protein (MopA) from Erythrobacter sp. strain SD21 is part of a unique enzymatic family that is capable of oxidizing soluble Mn(II). This enzyme contains two domains, an animal heme peroxidase domain, which contains the catalytic site, followed by a C-terminal calcium binding domain. Different from the bacterial Mn-oxidizing multicopper oxidase enzymes, little is known about MopA. To gain a better understanding of MopA and its role in Mn(II) oxidation, the 238-kDa full-length protein and a 105-kDa truncated protein containing only the animal heme peroxidase domain were cloned and heterologously expressed in Escherichia coli. Despite having sequence similarity to a peroxidase, hydrogen peroxide did not stimulate activity, nor was activity significantly decreased in the presence of catalase. Both pyrroloquinoline quinone (PQQ) and hemin increased Mn-oxidizing activity, and calcium was required. The Km for Mn(II) of the full-length protein in cell extract was similar to that of the natively expressed protein, but the Km value for the truncated protein in cell extract was approximately 6-fold higher than that of the full-length protein, suggesting that the calcium binding domain may aid in binding Mn(II). Characterization of the heterologously expressed MopA has provided additional insight into the mechanism of bacterial Mn(II) oxidation, which will aid in understanding the role of MopA and Mn oxidation in bioremediation and biogeochemical cycling.

Detection of Sentinel Lymph Nodes Using Indocyanine Green After Failing Scintigraphy in Merkel Cell Carcinoma.

Merkel cell carcinoma (MCC) is a rare but highly aggressive skin cancer that carries a high rate of lymph node involvement and death. The National Comprehensive Cancer Network recommends sentinel lymph node (SLN) biopsy for the staging of the disease. Scintigraphy using radioactive isotopes (RI) such as technetium 99m (Tc99) remains the gold standard for the detection of SLNs, however, recently indocyanine green (ICG) fluorescence imaging has been used to aid in the detection of SLNs.We present the case of a patient who presented with MCC of the face and two SLNs successfully identified with ICG fluorescence despite the fact that they were not detected by intraoperative scintigraphy using Tc99. The use of ICG fluorescence imaging in MCC is safe and improves the ability to detect SLNs when combined with RI.

Prospective associations between peer support, academic competence, and anxiety in college students.

Previous literature has demonstrated that peer support is instrumental for the promotion of adaptive academic and mental health outcomes; however, limited research has examined prospective directional associations between peer support and adjustment within college settings. The purpose of this study was to investigate the longitudinal associations between peer support, academic competence, and anxiety among U.S. college students. U.S. students from a diverse 4-year university (N = 251, 75% women, 24% men, and < 1% a different gender) reported on peer support, academic competence, and anxiety using validated questionnaires at two time points (Fall term of sophomore year and Spring term of senior year). Results showed that peer support was positively associated with academic competence over time but was not significantly related to future anxiety. Academic competence did not significantly predict peer support or anxiety over time, but anxiety was associated with lower future academic competence. These findings offer insight into how types of social relationships link with academic motivation and anxiety over time within educational settings.

The role of school friendship stability, instability, and network size in early adolescents' social adjustment.

This study examined longitudinal associations between early adolescents' school friendship stability, instability, and network size and their perceived social adjustment. The final sample consisted of 430 early adolescents residing in seven Midwestern schools (52% female, 47% Black, 42% White, 5% Hispanic or Latinx, and 6% Other). School friendship stability, instability, and network size were assessed via students' peer nominations of their same-grade friendships collected midway through their 7th and 8th grade years. Students also self-reported on several measures of social adjustment (their social satisfaction, social confidence, and school belonging). Results indicated having new friendships and having a larger friendship network at school were each more predictive of early adolescents' perceived social adjustment than was having maintained friendships or a consistent friend group within this context. However, school friendship stability consistently predicted greater perceived school belonging, whereas having a primarily new friend group and/or having lost more or most of a prior friend group predicted lower levels of this perception. Having lost school friendships was not predictive of early adolescents' social adjustment except when losses composed a significant proportion of their school friendship network (i.e., they had lost more or most of their school friendships from the year before). These findings provide valuable insights about peer friendship dynamics and social adjustment during a life stage critical to social development. (PsycInfo Database Record (c) 2022 APA, all rights reserved).

Use of Indocyanine Green Angiography for Real-Time Assessment of a Sternocleidomastoid Muscle Flap During Complex Facial Reconstruction.

Indocyanine green (ICG) angiography is a procedure that uses a fluorescent dye for a variety of medical diagnostics, including the real-time examination of blood flow in tissue. Herein, we report a case in which ICG angiography was used to assess the viability of a sternocleidomastoid (SCM) muscle flap during post-parotidectomy facial reconstruction. To our knowledge, this is the first report documenting the intraoperative use of ICG for the evaluation of SCM flap perfusion. ICG angiography may prove beneficial for cases involving complex reconstructions and suspected organ hypoperfusion.

Use of Indocyanine Green Fluorescent Imaging in the Assessment of a Tongue Flap After Lateral Hemiglossectomy.

Indocyanine green (ICG) angiography is a real-time imaging modality that can be used to assess intraoperative tissue perfusion. ICG dye has proven to be feasible, safe, and cost-effective, especially for muscle flaps during complex reconstructions. To our knowledge, we discuss the first use of ICG angiography for the real-time assessment of a tongue flap following left lateral hemiglossectomy. ICG angiography showed excellent perfusion of the tongue and tongue flap, which subsequently led to an uncomplicated postoperative recovery.

Latinx adolescents' ethnic-racial discrimination and expected future barriers over time.

Expecting discrimination in one's future occupation is known to have negative implications for adolescents' career pathways. However, little is known about how such discriminatory expectations emerge. The current contentious sociopolitical climate toward immigrants, especially those of Latinx heritage, has contributed to heightened discrimination against adolescents in this group. The present study examined how experiences of discrimination over time relate to youths' expectations of future occupational barriers among 148 Latinx adolescents at 3 annual waves (82% U.S.-born; 53% female; Mage = 13.54 at Wave 1). Results suggest that Latinx youth report increasing exposure to ethnic-racial discrimination and objectification as a perceived foreigner over time. Moreover, as Latinx youth perceived more ethnic-racial discrimination and foreigner objectification over the course of adolescence they increasingly expected to face racial and ethnic barriers in their future occupations. Implications of these findings for an increasing Latinx youth and working-age population in the United States are discussed. (PsycInfo Database Record (c) 2021 APA, all rights reserved).

Illuminating ethnic-racial socialization among undocumented Latinx parents and its implications for adolescent psychosocial functioning.

The purpose of this study is to examine how parents' documentation status informs their ethnic-racial socialization (ERS) practices and the subsequent implications for Latinx youths' psychological adjustment. The mixed-methods approach combined convergent and exploratory sequential designs to explore the breadth and depth of Latinx parents' messages to their children regarding race and ethnicity. Qualitative data were used to generate hypotheses that were tested quantitatively. Analysis of interviews revealed parents' concerns with obeying the law, avoiding interaction with others, teaching children how to deal with discrimination, the importance of transmitting their culture, and concerns for their children's ever-present fear and stress. Path analysis showed that undocumented parents utilized more cultural socialization and promotion of mistrust messages than their documented counterparts. More promotion of mistrust, in turn, was associated with higher levels of adolescent depressive symptoms. Given the current sociopolitical climate and ethnic-racial tensions in the United States, it is imperative to gain a more comprehensive understanding of the nuanced ERS practices Latinx families employ to both cope with and respond to this situation. (PsycInfo Database Record (c) 2020 APA, all rights reserved).

New approaches to detection and identification of Rickettsia africae and Ehrlichia ruminantium in Amblyomma variegatum (Acari: Ixodidae) ticks from the Caribbean.

Imported from Africa in the 1700s and despite frequent modern eradication efforts, Amblyomma variegatum (F.) spread through the Caribbean by cattle transport, small ruminants, and migrating birds. A. variegatum is a vector for Rickettsia africae, the causative agent of African tick bite fever, and Ehrlichia ruminantium, the causative agent of heartwater. We examined 95 A. variegatum and six Rhipicephalus (Boophilus) microplus (Canestrini) collected from cattle at an abattoir in Antigua. Engorged tick extracts adsorbed on Nobotu filter paper strips and new nested polymerase chain reaction (PCR) assays for E. ruminantium and Dermatophilus congolensis were used to evaluate these ticks for the presence of these pathogenic bacteria. Amblyomma ticks (62.4%) contained R. africae DNA by PCR/restriction fragment length polymorphism analysis and DNA sequencing of the OmpA and 17-kDa antigen genes. Twenty Amblyomma and two Rh. microplus contained E. ruminantium DNA. No E. chaffeensis, Anaplasma phagocytophilum, Coxiella burnetii, or D. congolensis DNA was detected in these ticks. The continued presence of Am. variegatum in the Caribbean poses a significant risk of infection in cattle with E. ruminantium and in humans by R. africae. Eradication efforts are essential to prevent the further spread of Am. variegatum.

Organic market gardening around the Paris agglomeration: agro-environmental performance and capacity to meet urban requirements.

Organic market gardening is often promoted by urban municipalities as a way to resource part of the food supply, creating new social links and protecting groundwater resources. The agronomical and environmental performance of six commercial organic market gardening farms supplying vegetables in Paris were evaluated and compared with other vegetable production systems. When expressed in terms of protein production, the yield of these systems appears rather low compared with the productive capacity of open-field organic cropping systems where vegetable production is inserted into rotation with other crops. Moreover, the requirement of producing infiltrated water meeting the drinking water standards seriously limits the allowable rate of fertilisation, thus limiting production. The data reported herein show that to supply the amount of vegetables required by the Paris agglomeration (12 million inhabitants) only by organic market gardening, 160,000-205,000 ha, i.e. 28-36 % of the agricultural area of the surrounding Ile-de-France region, would be required. We conclude that organic market gardening is only one of several other farming systems which can contribute to a re-localised supply of vegetables to large cities.

MopA, the Mn Oxidizing Protein From Erythrobacter sp. SD-21, Requires Heme and NAD+ for Mn(II) Oxidation.

Bacterial manganese (Mn) oxidation is catalyzed by a diverse group of microbes and can affect the fate of other elements in the environment. Yet, we understand little about the enzymes that catalyze this reaction. The Mn oxidizing protein MopA, from Erythrobacter sp. strain SD-21, is a heme peroxidase capable of Mn(II) oxidation. Unlike Mn oxidizing multicopper oxidase enzymes, an understanding of MopA is very limited. Sequence analysis indicates that MopA contains an N-terminal heme peroxidase domain and a C-terminal calcium binding domain. Heterologous expression and nickel affinity chromatography purification of the N-terminal peroxidase domain (MopA-hp) from Erythrobacter sp. strain SD-21 led to partial purification. MopA-hp is a heme binding protein that requires heme, NAD+, and calcium (Ca2+) for activity. Mn oxidation is also stimulated by the presence of pyrroloquinoline quinone. MopA-hp has a K M for Mn(II) of 154 ± 46 µM and k cat = 1.6 min-1. Although oxygen requiring MopA-hp is homologous to peroxidases based on sequence, addition of hydrogen peroxide and hydrogen peroxide scavengers had little effect on Mn oxidation, suggesting this is not the oxidizing agent. These studies provide insight into the mechanism by which MopA oxidizes Mn.

Food Particle Aspiration Associated with Hemorrhagic Shock: A Diagnostic Dilemma.

The hemodynamic compromise caused by a large aspirated food particle in the airway can become the focus of medical attention and a distraction from rare but fatal Heimlich maneuver related injuries after an incident of food aspiration. We herein present a case of an 84-year-old man who was brought to the emergency department after an episode of choking at a restaurant followed by several failed Heimlich maneuver attempts. Despite relieving the airway obstruction by extracting a large piece of steak from the airway, the patient remained hypotensive and required continued hemodynamic support. Repeated laboratory tests within 24 hrs of aspiration showed a significant decline in the hemoglobin level. A computed tomography (CT) scan of the abdomen and pelvis showed a lacerated liver with a large subcapsular hematoma draining into the pelvis. Conclusion. Hepatic rupture is a rare complication of Heimlich maneuver; this paper represents the second case report in the literature. It emphasizes the necessity of early identification and surveillance of fatal Heimlich maneuver complications in a high risk population.

Are we delivering two standards of care for pelvic trauma? Availability of angioembolization after hours and on weekends increases time to therapeutic intervention.

BACKGROUND: We hypothesized that patients with pelvic fractures and hemorrhage admitted during daytime hours were undergoing interventional radiology (IR) earlier than those admitted at night and on weekends, thereby establishing two standards of time to hemorrhage control. METHODS: The trauma registry (January 2008 to December 2011) was reviewed for patients admitted with pelvic fractures, hemorrhagic shock, and transfusion of at least 1 U of blood. The control group (DAY) was admitted from 7:30 AM to 5:30 PM Monday to Friday, while the study group (after hours [AHR]) was admitted from 5:30 PM to 7:30 AM, on weekends or holidays. RESULTS: A total of 191 patients met the criteria (45 DAY, 146 AHR); 103 died less than 24 hours and without undergoing IR (29% DAY group vs. 62% AHR, p < 0.001). Sixteen patients (all in AHR group) died while awaiting IR (p = 0.032). Eighty-eight patients (32 DAY, 56 AHR) survived to receive IR. Among these, the AHR group were younger (median, 30 years vs. 54 years; p = 0.007), more tachycardic (median pulse, 119 beats/min vs. 90 beats/min; p = 0.001), and had more profound shock (median base, -10 vs. -6; p = 0.006) on arrival. Time from admission to IR (median, 301 minutes vs. 193 minutes; p < 0.001) and computed tomographic scan to IR (176 minutes vs. 87 minutes, p = 0.011) were longer in the AHR group. There was no difference in the 30-day mortality by univariate analysis. However, after controlling for age, arrival physiology, injury severity, and degree of shock, the AHR group had a 94% increased risk of mortality. CONCLUSION: The current study demonstrated that patients admitted at night and on weekends have a significant increase in time to angioembolization compared with those arriving during the daytime and during the week. Multivariate regression noted that AHR management was associated with an almost 100% increase in mortality. While this is a single-center study and retrospective in nature, it suggests that we are currently delivering two standards of care for pelvic trauma, depending on the day and time of admission. LEVEL OF EVIDENCE: Therapeutic study, level II.

Removal of an intra-parotid foreign body without parotidectomy and dissection of the facial nerve.

EDUCATIONAL OBJECTIVES: At the conclusion of this presentation, the participants should be able to discuss how imaging and intra-operative facial nerve monitoring may be used in the removal of selected intraparotid foreign body without parotidectomy and dissection of the facial nerve. OBJECTIVES: 1) To present a rare case of a metallic intraparotid foreign body introduced as a projectile; 2) to discuss how CT images were used to guide the surgical exploration; and 3) To discuss the surgical approach used to retrieve an intraparotid foreign body without facial nerve dissection. STUDY DESIGN: This is a clinical case report with a review of literature. METHODS: We present the pertinent history and physical examination findings. We discuss the CT images. The technique of surgical exploration and foreign body retrieval is presented. RESULTS: This is the case of a man who presented to the emergency department with a metallic foreign body lodged in the parotid introduced accidentally as a projectile. CT images were analyzed and the patient underwent successful removal of the intraparotid foreign body with out parotidectomy and facial nerve dissection via a posterior approach and using facial nerve monitoring. CONCLUSION: Selected intraparotid foreign bodies may be removed without parotidectomy and facial nerve dissection if imaging shows it can be approached safely and intra-operative facial nerve monitoring is used.

8-(Hydroxymethyl)-3,N(4)-etheno-C, a potential carcinogenic glycidaldehyde product, miscodes in vitro using mammalian DNA polymerases.

8-(Hydroxymethyl)-3,N(4)-etheno-C (8-HM-epsilonC) is an exocyclic adduct resulting from the reaction of dC with glycidaldehyde, a mutagen and animal carcinogen. This compound has now been synthesized and its phosphoramidite incorporated site-specifically into a defined 25-mer oligonucleotide. In this study, the mutagenic potential of this adduct in the 25-mer oligonucleotide was investigated in an in vitro primer-template extension assay using four mammalian DNA polymerases. The miscoding potentials were also compared to those of an analogous derivative, 3,N(4)-etheno C (epsilonC), in the same sequence. Both adducts primarily blocked replication by calf thymus DNA polymerase alpha at the modified base, while human polymerase beta catalyzed measurable replication synthesis through both adducts. Nucleotide insertion experiments showed that dA and dC were incorporated by pol beta opposite either adduct, which would result in a C --> T transition or C --> G transversion. Human polymerase eta, a product of the xeroderma pigmentosum variant (XP-V) gene, catalyzed the most efficient bypass of the two lesions with 25% and 32% for 8-HM-epsilonC and epsilonC bypassed after 15 min. Varying amounts of all four bases opposite the modified bases resulted with pol eta. Human polymerase kappa primarily blocked synthesis at the base prior to the adduct. However, some specific misincorporation of dT resulted, forming an epsilonC.T or 8-HM-epsilonC.T pair. From these data, we conclude that the newly synthesized glycidaldehyde-derived adduct, 8-HM-epsilonC, is a miscoding lesion. The bypass efficiency and insertion specificity of 8-HM-epsilonC and epsilonC were similar for all four polymerases tested, which could be attributed to the similar planarity and sugar conformations for these two derivatives as demonstrated by molecular modeling studies.