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1.
Artigo em Inglês | MEDLINE | ID: mdl-37786807

RESUMO

Background: Cardiac optical mapping is an imaging technique that measures fluorescent signals across a cardiac preparation. Dual optical imaging of voltage-sensitive and calcium-sensitive probes allows for simultaneous recordings of cardiac action potentials and intracellular calcium transients with high spatiotemporal resolution. The analysis of these complex optical datasets is both time intensive and technically challenging; as such, we have developed a software package for semi-automated image processing and analysis. Herein, we report an updated version of our software package (KairoSight-3.0) with features to enhance the characterization of cardiac parameters using optical signals. Methods: To test software validity and applicability, we used Langendorff-perfused heart preparations to record transmembrane voltage and intracellular calcium signals from the epicardial surface. Isolated hearts from guinea pigs and rats were loaded with a potentiometric dye (RH237) and/or calcium indicator dye (Rhod-2AM) and fluorescent signals were acquired. We used Python 3.8.5 programming language to develop the KairoSight-3.0 software. Cardiac maps were validated with a user-specified manual mapping approach. Results: Manual maps of action potential duration (30 or 80 % repolarization), calcium transient duration (30 or 80 % reuptake), action potential and calcium transient alternans were constituted to validate the accuracy of software-generated maps. Manual and software maps had high accuracy, with >97 % of manual and software values falling within 10 ms of each other and >75 % within 5 ms for action potential duration and calcium transient duration measurements (n = 1000-2000 pixels). Further, our software package includes additional measurement tools to analyze signal-to-noise ratio, conduction velocity, action potential and calcium transient alternans, and action potential-calcium transient coupling time to produce physiologically meaningful optical maps. Conclusions: KairoSight-3.0 has enhanced capabilities to perform measurements of cardiac electrophysiology, calcium handling, alternans, and the excitation-contraction coupling with satisfactory accuracy.

2.
Toxicol Sci ; 197(1): 79-94, 2023 12 21.
Artigo em Inglês | MEDLINE | ID: mdl-37812252

RESUMO

Di-2-ethylhexyl phthalate (DEHP) is commonly used in the manufacturing of plastic materials, including intravenous bags, blood storage bags, and medical-grade tubing. DEHP can leach from plastic medical products, which can result in inadvertent patient exposure. DEHP concentrations were measured in red blood cell units stored between 7 and 42 days (17-119 µg/ml). Using these concentrations as a guide, Langendorff-perfused rat heart preparations were acutely exposed to DEHP. Sinus activity remained stable with lower doses of DEHP (25-50 µg/ml), but sinus rate declined by 43% and sinus node recovery time (SNRT) prolonged by 56.5% following 30-min exposure to 100 µg/ml DEHP. DEHP exposure also exerted a negative dromotropic response, as indicated by a 69.4% longer PR interval, 108.5% longer Wenckebach cycle length (WBCL), and increased incidence of atrioventricular (AV) uncoupling (60-min exposure). Pretreatment with doxycycline partially rescued the effects of DEHP on sinus activity, but did not ameliorate the effects on AV conduction. DEHP exposure also prolonged the ventricular action potential and effective refractory period, but had no measurable effect on intracellular calcium transient duration. Follow-up studies using human-induced pluripotent stem cell-derived cardiomyocytes confirmed that DEHP slows electrical conduction in a time (15 min-3 h) and dose-dependent manner (10-100 µg/ml). Previous studies have suggested that phthalate toxicity is specifically attributed to metabolites of DEHP, including mono-2-ethylhexylphthalate. This study demonstrates that DEHP exposure also contributes to cardiac dysfunction in a dose- and time-dependent manner. Future work is warranted to investigate the impact of DEHP (and its metabolites) on human health, with special consideration for clinical procedures that employ plastic materials.


Assuntos
Dietilexilftalato , Ácidos Ftálicos , Humanos , Ratos , Animais , Plastificantes/toxicidade , Dietilexilftalato/toxicidade , Ácidos Ftálicos/metabolismo , Potenciais de Ação
3.
bioRxiv ; 2023 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-37293060

RESUMO

Di-2-ethylhexylphthalate (DEHP) is commonly used in the manufacturing of plastic materials, including intravenous bags, blood storage bags, and medical-grade tubing. DEHP can leach from plastic medical products, which can result in inadvertent patient exposure. DEHP concentrations were measured in red blood cell (RBC) units stored between 7-42 days (23-119 µg/mL). Using these concentrations as a guide, Langendorff-perfused rat heart preparations were acutely exposed to DEHP. Sinus activity remained stable with lower doses of DEHP (25-50 µg/mL), but sinus rate declined by 43% and sinus node recovery time prolonged by 56.5% following 30-minute exposure to 100 µg/ml DEHP. DEHP exposure also exerted a negative dromotropic response, as indicated by a 69.4% longer PR interval, 108.5% longer Wenckebach cycle length, and increased incidence of atrioventricular uncoupling. Pretreatment with doxycycline partially rescued the effects of DEHP on sinus activity, but did not ameliorate the effects on atrioventricular conduction. DEHP exposure also prolonged the ventricular action potential and effective refractory period, but had no measurable effect on intracellular calcium transient duration. Follow-up studies using hiPSC-CM confirmed that DEHP slows electrical conduction in a time (15 min - 3 hours) and dose-dependent manner (10-100 µg/mL). Previous studies have suggested that phthalate toxicity is specifically attributed to metabolites of DEHP, including mono-2-ethylhexyl phthalate (MEHP). This study demonstrates that DEHP exposure also contributes to cardiac dysfunction in a dose- and time-dependent manner. Future work is warranted to investigate the impact of DEHP (and its metabolites) on human health, with special consideration for clinical procedures that employ plastic materials.

4.
bioRxiv ; 2023 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-37205349

RESUMO

Background: Cardiac optical mapping is an imaging technique that measures fluorescent signals across a cardiac preparation. Dual optical mapping of voltage-sensitive and calcium-sensitive probes allow for simultaneous recordings of cardiac action potentials and intracellular calcium transients with high spatiotemporal resolution. The analysis of these complex optical datasets is both time intensive and technically challenging; as such, we have developed a software package for semi-automated image processing and analysis. Herein, we report an updated version of our software package ( KairoSight-3 . 0 ) with features to enhance characterization of cardiac parameters using optical signals. Methods: To test software validity and applicability, we used Langendorff-perfused heart preparations to record transmembrane voltage and intracellular calcium signals from the epicardial surface. Isolated hearts from guinea pigs and rats were loaded with a potentiometric dye (RH237) and/or calcium indicator dye (Rhod-2AM) and fluorescent signals were acquired. We used Python 3.8.5 programming language to develop the KairoSight-3 . 0 software. Cardiac maps were validated with a user-specified manual mapping approach. Results: Manual maps of action potential duration (30 or 80% repolarization), calcium transient duration (30 or 80% reuptake), action potential and calcium transient alternans were constituted to validate the accuracy of software-generated maps. Manual and software maps had high accuracy, with >97% of manual and software values falling within 10 ms of each other and >75% within 5 ms for action potential duration and calcium transient duration measurements (n=1000-2000 pixels). Further, our software package includes additional cardiac metric measurement tools to analyze signal-to-noise ratio, conduction velocity, action potential and calcium transient alternans, and action potential-calcium transient coupling time to produce physiologically meaningful optical maps. Conclusions: KairoSight-3 . 0 has enhanced capabilities to perform measurements of cardiac electrophysiology, calcium handling, and the excitation-contraction coupling with satisfactory accuracy. Graphical Abstract Demonstrating Experimental and Data Analysis Workflow: Created with Biorender.com.

5.
J Homosex ; 70(2): 277-290, 2023 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-34264171

RESUMO

Asian American sexual minority individuals (AASMI) face the challenge of navigating two identities as both a sexual minority and a racial minority. However, the research base examining AASMI dual-identities remains underdeveloped. In the current study, we investigated the link between AASMI dual-identity centrality and their health and wellbeing using a subsample of 303 AASMI drawn from the Social Justice Sexuality Project dataset (n = 4,953). We conducted structural equation modeling (SEM) to test our hypothesized model and used bootstrap analysis to test the indirect effects therein. Findings indicated strong support for our model, which theorized that dual-identity centrality among AASMI can act as a "double-edged sword" on their health, whereby the process worsens their health through increased discomfort in their racial/ethnic community while simultaneously improving it through increased outness. Implications for future research and new avenues of intervention efforts at improving AASMI health are discussed.


Assuntos
Asiático , Minorias Sexuais e de Gênero , Humanos , Grupos Minoritários , Sexualidade , Identidade de Gênero
7.
Artigo em Inglês | MEDLINE | ID: mdl-36220545

RESUMO

Atrazine has been widely used in the world and caused environmental pollution, especially soil pollution. When assessing the toxicity of atrazine in soil, most studies used standardized artificial soils, while few studies focused on the real soil environments. In the present study, three natural soils and artificial soil were selected as test soils to study and compare the toxicities of atrazine to Eisenia fetida. Acute toxicity of atrazine was determined by filter paper and soil tests. In chronic toxicity study, after atrazine exposure, the content of reactive oxygen species in Eisenia fetida significantly increased and showed a dose-response relationship. The activity changes of three antioxidant enzymes and glutathione transferase showed that atrazine had obvious oxidative stress effect on earthworms. The contents of malondialdehyde and 8-hydroxy deoxyguanosine in 0.1 and 1 mg/kg atrazine treatment groups were significantly higher than the control, indicating that medium and high concentrations of atrazine could cause lipid and DNA damage in Eisenia fetida. The acute toxicity results and the integrated biomarker response index for chronic toxicity indicated that the toxicity order of atrazine was: red clay > fluvo-aquic soil > artificial soil > black soil, and that the toxicity of atrazine in artificial soil was not representative of its toxicity in real soil environment. The results of correlation analysis showed that three soil property parameters of organic carbon, organic matter and sand were most related to the toxicity of atrazine.


Assuntos
Atrazina , Oligoquetos , Poluentes do Solo , Animais , Oligoquetos/fisiologia , Solo , Atrazina/toxicidade , Poluentes do Solo/toxicidade , Malondialdeído , Estresse Oxidativo
8.
Acad Radiol ; 30(2): 370-378, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-35879209

RESUMO

RATIONALE AND OBJECTIVES: Attracting more students to nuclear medicine is imperative to improving diversity and meeting growing staffing needs. In this study, we implemented a short seminar about nuclear medicine and evaluated its impact on student perceptions of the field. MATERIALS AND METHODS: We developed and presented 30-minute "Introduction to Nuclear Medicine" seminars to undergraduate college students and preclinical medical students. After the seminars, participants completed a post-pre survey to determine perceived changes to their perspective of nuclear medicine. Responses were coded on a Likert 1-5 scale with pre- and post- seminar results compared using T-test of means and analysis of variance. RESULTS: Of the 83 students who attended the seminar, 79 (95.1%) students participated in the survey including 67 preclinical medical students and 12 undergraduate students. Of the 78 participants who provided demographic information, there were 38 (48.7%) women, 5 (6.4%) first-generation college students, and 39 (50.0%) people who identified as either multiracial or a race other than White/Caucasian. Among all participants (n = 79), there was a significant increase in perceived understanding of nuclear medicine (p < 0.001), confidence in ability to pursue nuclear medicine (p < 0.001), and interest in becoming a nuclear medicine professional (p < 0.001). Perceived increases in knowledge were highest among first-year medical students (p = 0.031), while interest (p = 0.40) and confidence (p = 0.85) in pursuing nuclear medicine did not vary by educational level. CONCLUSION: Perceptions of student interest in nuclear medicine can be improved using an easily implemented, short seminar at the undergraduate college and preclinical medical school level.


Assuntos
Educação de Graduação em Medicina , Medicina Nuclear , Estudantes de Medicina , Humanos , Feminino , Masculino , Currículo , Escolaridade , Recursos Humanos , Educação de Graduação em Medicina/métodos
9.
Rand Health Q ; 9(3): 15, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35837508

RESUMO

Behavioral health (BH) problems are common in the military and can adversely affect force readiness. Research suggests that primary care-behavioral health (PCBH) integration can improve BH outcomes by making high-quality BH care available in more accessible settings. However, sustaining high-quality implementation of PCBH is challenging. The authors conducted a process evaluation of the PCBH program in the military health system to understand why the program is working as it is and provide recommendations for quality improvement. They conducted semistructured interviews, rigorously coded the qualitative data to identify causal links, and created and validated causal loop diagrams that provide a visualization of how the system is working. Findings fall into four key areas: staffing and capabilities, valued tasks, program stewardship, and fostering program awareness and support. Overall, the authors found that the PCBH program is highly valued by primary care staff. However, the PCBH care model is inconsistently adhered to, owing to a combination of staff preferences, local pressures, and lack of knowledge of PCBH staff roles. Recommendations are offered to improve program implementation.

10.
Acad Radiol ; 2022 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-35090828

RESUMO

RATIONALE AND OBJECTIVES: The Radiology Scholars Certificate Program (RSCP) is an extracurricular program created for preclinical medical students to address disparities in radiology education and exposure during medical school. MATERIALS AND METHODS: The RSCP was designed as a year-long program for first- and second-year medical students. The 4 key components of the RSCP are: Exposure to radiology through shadowing, knowledge acquisition through self-paced case-based learning modules, knowledge application in interactive workshops, and completion of a scholarly project. Students are required to complete at least 3 hours of shadowing, attend at least 3 workshops, complete self-paced online modules, and complete a capstone project on a topic of their choosing. Pre- and post-program surveys were administered to assess trends in participants' perception of the field and imaging-related clinical knowledge. RESULTS: In the first year of the RSCP, 55% of the matriculating class enrolled and of those, 84% completed the program. Approximately half of participants were female. Participants demonstrated significant improvement in radiology knowledge, with average scores improving from 52.8% to 68.6% (p < .001) on the knowledge-related survey questions. Significant improvements were also observed in student-reported confidence with ordering and interpreting imaging studies and in their perceptions of the field. CONCLUSION: The RSCP is an effective tool for addressing deficits in radiology education and exposure during medical school. It is designed to be run by senior medical students under radiology resident and attending supervision. With motivated student and radiologist investment, the RSCP should be easily replicable in medical training programs worldwide.

11.
Environ Res ; 194: 110705, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33400946

RESUMO

Azoxystrobin, a widely used broad-spectrum strobilurin fungicide, may pose a potential threat in agricultural ecosystems. To assess the ecological risk of azoxystrobin in real soil environments, we performed a study on the toxic effects of azoxystrobin on earthworms (Eisenia fetida) in three different natural soils (fluvo-aquic soil, black soil and red clay soil) and an artificial soil. Acute toxicity of azoxystrobin was determined by filter paper test and soil test. Accordingly, exposure concentrations of chronic toxicity were set at 0, 0.1, 1.0 and 2.5 mg kg-1. For chronic toxicity test, reactive oxygen species, activity of antioxidant enzymes (superoxide dismutase, catalase and peroxidase), detoxifying enzyme (glutathione transferase), level of lipid peroxidation (malondialdehyde) and level of oxygen damage of DNA (8-hydroxydeoxyguanosine) in earthworms were determined on the 7th, 14th, 21st, 28th, 42nd and 56th days after treatment. Both acute and chronic toxic results showed azoxystrobin exhibit higher toxicity in natural soil than in artificial soil, indicating that traditional artificial soil testing method underestimate ecotoxicity of azoxystrobin in a real agricultural environment on the earthworm population. Combining with the analysis of soil physicochemical properties, the present experiment provided scientific guidance for rational application of azoxystrobin in agricultural production systems.


Assuntos
Oligoquetos , Poluentes do Solo , Animais , Catalase/metabolismo , Ecossistema , Malondialdeído , Oligoquetos/metabolismo , Estresse Oxidativo , Pirimidinas , Solo , Poluentes do Solo/toxicidade , Estrobilurinas/toxicidade , Superóxido Dismutase/metabolismo
12.
Skinmed ; 18(5): 312-314, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33160443

RESUMO

A 67-year-old Scottish woman presented to her general practitioner with a subcentimeter lump between her shoulder blades. The lump was suspected to be an epidermal cyst and was excised. The patient had a history of controlled diabetes. Most summers, she spent a month near a beach resort in Mexico. The lump reappeared after 6 months within the scar area and was re- excised. Both skin excisions were performed in the primary care setting without histologic assessment.


Assuntos
Cisto Epidérmico/diagnóstico , Dermatopatias Infecciosas/diagnóstico , Idoso , Cicatriz/patologia , Feminino , Humanos , Recidiva , Dermatopatias Infecciosas/patologia , Dermatopatias Infecciosas/cirurgia
13.
Stem Cell Res ; 46: 101806, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32446240

RESUMO

In this study, we established induced pluripotent stem (iPS) cell lines from postmortem dura-derived fibroblasts of four control individuals with low polygenic risk score for psychiatric disorders including schizophrenia and bipolar disorder. The fibroblasts were reprogrammed into iPS cells using episomal vectors carrying OCT3/4, SOX2, KLF4, L-Myc, LIN28 and shRNA-p53. All iPS cell lines showed the same genotype with parental postmortem brain tissues, expressed pluripotency markers, and exhibited the differentiation potency into three embryonic germ layers.


Assuntos
Células-Tronco Pluripotentes Induzidas , Encéfalo , Diferenciação Celular , Linhagem Celular , Fibroblastos , Genótipo , Humanos , Fator 4 Semelhante a Kruppel , Transcriptoma
14.
LGBT Health ; 7(1): 37-46, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31755811

RESUMO

Purpose: We examined how substance use differed as a function of sex assigned at birth and gender identity (cisgender, transgender, or nonbinary/genderqueer) by type of substance. We sought to test whether current gender identity and sex assigned at birth were key factors in substance use among a large contemporary sample that included transgender and nonbinary/genderqueer adolescents. Methods: We analyzed data from a large national U.S. sample of sexual and gender minority (SGM) adolescents (n = 11,129) collected between April and December 2017. Chi-square tests of independence were used to test whether substance use behaviors varied by sex assigned at birth and gender identity. A series of multivariate logistic regression models tested the odds of substance use by sex assigned at birth and gender identity, as well as the interaction between sex assigned at birth and gender identity. Results: More than half of our sample reported lifetime alcohol use, and one-fourth of the sample reported lifetime marijuana use. Adolescents assigned male at birth had higher prevalence of substance use compared with adolescents assigned female at birth (AFAB). Multivariate models elucidated greater risk for most substance use outcomes for transgender adolescents compared with cisgender adolescents. We found significant interaction effects between gender identity and sex assigned at birth for recent alcohol use and lifetime and recent cigarette use among adolescents AFAB. Conclusions: These findings have implications for stakeholders who develop nationally representative surveys, researchers who examine substance use disparities among SGM adolescents, and mental health professionals who treat underage substance use among vulnerable populations.


Assuntos
Minorias Sexuais e de Gênero/psicologia , Transtornos Relacionados ao Uso de Substâncias/epidemiologia , Adolescente , Feminino , Identidade de Gênero , Humanos , Masculino , Análise para Determinação do Sexo , Minorias Sexuais e de Gênero/estatística & dados numéricos , Estados Unidos/epidemiologia
15.
Insects ; 11(1)2019 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-31861592

RESUMO

Potato psyllid (Bactericera cockerelli) is one of the most important pests in potatoes (Solanum tuberosum L.) due to its feeding behavior and the transmission of a bacterium (Candidatus Liberibacter solanacearum) that causes zebra chip disease, altering the quality of the potato tuber and the fried potato chip or french fry. This pest is thus a threat to the chip potato industry and often requires preventive measures including the use of costly insecticides. The objectives of this research were to monitor the variation in B. cockerelli adult abundance and to evaluate the risk of zebra chip disease in northwestern New Mexico, USA. Yellow sticky traps were used to collect the pest at the Agricultural Experiment Station at Farmington, NM and in nearby commercial fields at the Navajo Agricultural Products Industry (NAPI) and Navajo Mesa Farms during the 2017-2019 period. The collected adult pests were analyzed at Texas A & M University for the presence of Candidatus L. solanacearum (Lso). The results showed field infestation by B. cockerelli in early June and that the population peaked during the second half of July and decreased as the potato growing season progressed. However, a second less important peak of the pest was revealed around mid- to late-August, depending on the growing season and field. While the B. cockerelli population increased linearly with average air temperature, it showed strong third order polynomial relationships with the accumulated thermal units and the Julian days. The test of B. cockerelli for the Lso infection revealed a low incidence of the pathogen varying from 0.22% to 6.25% and the infected adult B. cockerelli were collected during the population peak period. The results of this study may be helpful to potato growers in pest management decision-making and control. However, more study is needed to evaluate zebra chip disease in terms of its prevention and economic impact, and to develop economic thresholds and pest management programs for northwestern New Mexico and neighboring regions.

16.
Insects ; 10(11)2019 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-31653101

RESUMO

This study was conducted to monitor the population dynamics of six major insect pests at the NMSU Agricultural Science Center at Farmington (ASC-Farmington) and within an adjacent commercial farm (Navajo Agricultural Products Industry, NAPI) for more effective and efficient pest management during the 2013-2019 period. Specific pheromone traps, sticky and net traps were used to collects moths of beet armyworm (Spodoptera exigua), cabbage looper (Trichoplusia ni), corn earworm (Helicoverpa zea), fall armyworm (Spodoptera frugiperda), potato psyllid (Bactericera cockerelli), and western bean cutworm (Striacosta albicosta). These insects generally appear in early June and their population decreases toward the end of August/early September with different peak times and magnitudes during July and August. Bactericera cockerelli was not substantially present in the commercial farm due to intensive insecticide application. Overall, all six insect species were present at ASC-Farmington, with relative abundance, in percent of the total collected moths by all traps, varying from 6.5 to 19% for Trichoplusia ni, 16 to 29.2% for Spodoptera exigua, 1.5 to 20.6% for Striacosta albicosta, 10 to 25% for Helicoverpa zea, 18.5 to 25.6% for Spodoptera frugiperda and 8.5 to 26.9% for Bactericera cockerelli. In NAPI's commercial field, while the potato psyllid Bactericera cockerelli was not recorded, Trichoplusia ni and Spodoptera exigua showed decreasing rates that varied from 27.5 to 4.2% and from 49.3 to 7.8%, respectively. Striacosta albicosta, Helicoverpa zea and Spodoptera exigua showed increasing rates varying from 2.9 to 28%, from 7.8 to 25.3% and from 10.9 to 52%, respectively. The results of this study could serve as a guideline for sustainable management strategies for each of the six species for production profitability.

17.
J Am Soc Mass Spectrom ; 30(6): 1115-1125, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30963456

RESUMO

Tandem ion mobility (IM) enables the characterization of subpopulations of ions from larger ensembles, including differences that cannot be resolved in a single dimension of IM. Tandem IM consists of at least two IM regions that are each separated by an ion selection region. In many implementations of tandem IM, ions eluting from a dimension of separation are filtered and immediately transferred to the subsequent dimension of separation (selection-only experiments). We recently reported a mode of operation in which ions eluting from a dimension are trapped prior to the subsequent dimension (selection-trapping experiments), which was implemented on an instrument constructed using the structures for lossless ion manipulations (SLIM) architecture. Here, we use a combination of experiments and trajectory simulations to characterize aspects of the selection, trapping, and separation processes underlying these modes of operation. For example, the actual temporal profile of filtered ions can be very similar to the width of the waveforms used for selection, but depending on experimental parameters, can differ by up to ± 500 µs. Experiments and simulations indicate that ions in selection-trapping experiments can be spatially focused between dimensions, which removes the broadening that occurred during the preceding dimension. During focusing, individual ions are thermalized, which aligns and establishes common initial conditions for the subsequent dimension. Therefore, selection-trapping experiments appear to offer significant advantages relative to selection-only experiments, which we anticipate will become more pronounced in future experiments that make use of longer IM separations, additional dimensions of analysis, and the outcomes of this study. Graphical Abstract.

18.
Psychol Women Q ; 43(3): 381-397, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35237026

RESUMO

Using the theoretical lenses of intersectionality and racial-ethnic socialization, we conducted a focus group study with 29 Black women. We analyzed transcripts for the sources of messages about skin color and hair and for participants' responses to these messages via a grounded theory approach. Family members were the primary source of messages about skin color and hair. Peers and the media also communicated such messages. Messages ranged from endorsement of Western standards of beauty to an embrace of darker skin colors and natural hair texture. Rather than serving as passive recipients of messages, participants sifted through and reconciled messages with varying degrees of resolution. Their accounts reflected their intersectional experiences as Black women, representing a variety of physical attributes. We discuss the influence of these physical attributes on their individual racial-gender identity development in light of a second burgeoning Black hair movement that embraces Black natural hair in the U.S. Findings may help families and others build understanding of and increase sensitivity towards the intra- and interpersonal implications of colorism for Black women. Findings may also inform institutional policies (e.g., school, work) and practices such that they no longer create barriers or yield consequences for the Black women navigating these settings.

19.
J Homosex ; 66(13): 1769-1796, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30222074

RESUMO

Recent scholars have underscored how the experiences of LGBT people of color cannot be fully understood by considering only the independent contributions of race and sexual orientation. Framed by an intersectional lens, the current study seeks to address this gap in understanding by considering the role of nativity on the health and wellbeing of Black sexual minority adults; we also examined the moderating effects of family support and racial community climate on this relationship. Using national data from the Social Justice Sexuality Project (N = 2,166), we discovered that foreign-born Black LGBT adults had similar levels of psychological wellbeing and physical health as their native counterparts; family support and racial community climate did not moderate this relationship. Our findings did, however, substantiate the importance of family and community support for all Black LGBT adults, regardless of immigration status. Implications of this finding, in addition to directions for future intersectional work on racial minority LGBT people, are discussed.


Assuntos
Negro ou Afro-Americano/psicologia , Emigrantes e Imigrantes/psicologia , Minorias Sexuais e de Gênero/psicologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Nível de Saúde , Humanos , Masculino , Pessoa de Meia-Idade , Sexualidade , Adulto Jovem
20.
J Environ Manage ; 220: 191-197, 2018 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-29778955

RESUMO

The use of controlled-release urea (CRU) has become one of best management practices for increasing crop yield and improving nitrogen (N) use efficiency (NUE). However, the effects of CRU on direct-seeded rice are not well understood while direct-seeding has gradually replaced transplanting due to increasing labor cost and lack of irrigation water. The objective of this two-year field experiment was to compare the effects of the CRU at four rates (120, 180, 240 and 360 kg N ha-1, CRU1, CRU2, CRU3 and CRU4, respectively) with a conventional urea fertilizer (360 kg N ha-1; U) and a control (no N fertilizer applied; CK) on yield, biomass, NUE of direct-seeded rice and soil nutrients. The results indicated that the successive release rates of N from CRU corresponded well to the N requirements of rice. The use of CRU3 and CRU4 increased rice grain yields by 20.8 and 28.7%, respectively, compared with U. In addition, the NUEs were improved by all CRU treatments compared to the U treatment. Concentrations of NO3--N and NH4+-N in the soil were increased, especially during the later growth stages of the rice, and the leaching of N was reduced with CRU treatments. In conclusion, applying CRU on direct-seeded rice increased the crops yields and NUE, increased nitrogen availability at the late growth stages, and reduced N leaching.


Assuntos
Fertilizantes , Nitrogênio , Oryza/crescimento & desenvolvimento , Ureia , Agricultura , Preparações de Ação Retardada , Solo
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