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1.
Conserv Physiol ; 11(1): coad021, 2023.
Article in English | MEDLINE | ID: mdl-37152447

ABSTRACT

Environmental contamination of bisphenol A (BPA) is a widespread and multifaceted issue with vast ecological, social and economic consequences. Thus, understanding how local environmental conditions, such as temperature, interact with BPA to affect populations and community dynamics remain important areas of research. Here, we conduct laboratory experiments aimed at understanding how environmental gradients of both temperature and BPA concentration influence freshwater phytoplankton population growth and community structure. We exposed phytoplankton assemblages comprised of three common species of green algae (Chlorella vulgaris, Ankistrodesmus braunii and Scenedesmus quadricauda) as well as isolates of each individual species to three BPA concentrations (0, 2, 13 mg/L BPA) and three temperatures (18, 23, 27°C) monitoring population growth and community structure (via biovolume). We observed antagonistic interactions between BPA and warmer temperatures, such that when warmer temperatures decreased growth (observed with A. braunii), high concentrations of BPA elevated growth at these warm temperatures; however, when warmer temperatures increased growth (C. vulgaris, S. quadricauda), high BPA concentrations diminished these gains. Although BPA exposure inhibited the growth of most C. vulgaris populations, growth was not reduced in A. braunii or S. quadricauda populations exposed to 2 mg/L BPA. Phytoplankton assemblage evenness (Pielou evenness index) decreased as BPA concentration increased and was consistently lowest under 27°C. Community composition was similar in assemblages cultured under 0 and 2 mg/L BPA under 18 and 23°C but was most similar between assemblages cultured under 2 and 13 mg/L BPA under 27°C. These results indicate that local environmental temperatures can mediate the consequences of BPA for freshwater phytoplankton growth rates and community structure and that BPA can diminish potential gains of increased growth rate for warm-adapted phytoplankton species at high environmental temperatures.

2.
Ecology ; 102(4): e03295, 2021 04.
Article in English | MEDLINE | ID: mdl-33556190

ABSTRACT

Disturbance often increases local-scale (α) diversity by suppressing dominant competitors. However, widespread disturbances may also reduce biotic heterogeneity (ß diversity) by making the identities and abundances of species more similar among patches. Landscape-scale (γ) diversity may also decline if disturbance-sensitive species are lost. California's vernal pool plant communities are species rich, in part because of two scales of ß diversity: (1) within pools, as species composition changes with depth (referred to here as vertical ß diversity), and (2) between pools, in response to dispersal limitation and variation in pool attributes (referred to here as horizontal ß diversity). We asked how grazing by livestock, a common management practice, affects vernal pool plant diversity at multiple hierarchical spatial scales. In terms of abundance-weighted diversity, grazing increased α both within local pool habitat zones and at the whole-pool scale, as well as γ at the pasture scale without influencing horizontal or vertical ß diversity. In terms of species richness, increases in α diversity within habitat zones and within whole pools led to small decreases in horizontal ß diversity as species occupancy increased. This had a dampened effect on species richness at the γ (pasture) scale without any loss of disturbance-sensitive species. We conclude that grazing increases species richness and evenness (α) by reducing competitive dominance, without large disruptions to the critical spatial heterogeneity (ß) that generates high landscape-level diversity (γ).


Subject(s)
Biodiversity , Ecosystem , California , Plants , Seasons
4.
J Prof Nurs ; 32(4): 306-13, 2016.
Article in English | MEDLINE | ID: mdl-27424931

ABSTRACT

UNLABELLED: Research shows that holistic admissions review practices can increase diversity across students without decreasing the workforce preparedness and academic success of students. Therefore, many disciplines have readily adopted the widespread use of holistic admissions review. Despite its proven effectiveness in addressing student diversity, nursing has been slow to implement holistic admissions review. PURPOSE: The purpose of this study was to gain a better understanding of the barriers to implementing holistic admissions review in nursing and the feasibility of adopting holistic admissions review across nursing programs. METHODS: A biphasic qualitative research study was conducted with nursing deans from across the United States. Qualitative data collection consisted of two phases of focus group discussions conducted over a 3-month period. The qualitative data were analyzed using content analysis. The categories and subcategories identified in Phase 1 informed the discussion in Phase 2. RESULTS: One overarching category from Phase 1 was identified, which was the lack of nursing schools' knowledge regarding holistic admissions review. Four subcategories also identified in Phase 1 included the need for better dissemination of evidence, the need for additional support from university leaders and administrators, the need for legal guidance to facilitate implementation of holistic admissions review, and ensuring appropriate resources to support the holistic admissions review process. Three categories emerged in Phase 2, which included everyone's buy-in is required, the need for a model, and a need for training. CONCLUSION: The adoption of holistic admissions review in nursing may be feasible. However, certain barriers need to be overcome so that nursing schools can successfully take on this process. Therefore, five recommendations have been developed to assist nursing schools in the implementation of holistic admissions review. These recommendations include increasing knowledge and understanding of holistic admissions review among nursing deans; obtaining buy-in and support for holistic admissions review and conducting a self-assessment of current admissions practices; providing nursing administrators, faculty, and staff with diversity training; and conducting further research to identify factors most critical for success in nursing. Although the transition to a holistic admissions process requires some effort, arming ourselves with the appropriate tools will mitigate barriers during implementation.


Subject(s)
Cultural Diversity , Nurse Administrators , School Admission Criteria/trends , Focus Groups , Humans , Leadership , Models, Educational , Qualitative Research , Schools, Nursing , United States
5.
Article in English | MEDLINE | ID: mdl-26924541

ABSTRACT

Health profession schools use interviews during the admissions process to identify certain non-cognitive skills that are needed for success in diverse, inter-professional settings. This study aimed to assess the use of interviews during the student admissions process across health disciplines at schools in the United States of America in 2014. The type and frequency of non-cognitive skills assessed were also evaluated. Descriptive methods were used to analyze a sample of interview rubrics collected as part of a national survey on admissions in the health professions, which surveyed 228 schools of medicine, dentistry, pharmacy, nursing, and public health. Of the 228 schools, 130 used interviews. The most desirable non-cognitive skills from 34 schools were identified as follows: communication skills (30), motivation (22), readiness for the profession (17), service (12), and problem-solving (12). Ten schools reported using the multiple mini-interview format, which may indicate potential for expanding this practice. Disparities in the use of interviewing across health professions should be verified to help schools adopt interviews during student admissions processes.


Subject(s)
Health Occupations/education , Interviews as Topic , School Admission Criteria , Cognition , Communication , Humans , Motivation , Surveys and Questionnaires , United States
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