RESUMO
The findings reported in this paper are based on surveys of U.S. high school students who registered and managed their science and engineering fair (SEF) projects through the online Scienteer website over the three years 2019/20, 2020/21, and 2021/22. Almost 2500 students completed surveys after finishing all their SEF competitions. We added a new question in 2019/20 to our on-going surveys asking the students whether their high school location was urban, suburban, or rural. We learned that overall, 74% of students participating in SEFs indicated that they were from suburban schools. Unexpectedly, very few SEF participants, less than 4%, indicated that they were from rural schools, even though national data show that more than 20% of high school students attend rural schools. Consistent with previous findings, Asian and Hispanic students indicated more successful SEF outcomes than Black and White students. However, whereas Asian students had the highest percentage of SEF participants from suburban vs. urban schools- 81% vs. 18%, Hispanic students had the most balanced representation of participants from suburban vs. urban schools- 55% vs. 39%. Differences in students' SEF experiences based on gender and ethnicity showed the same patterns regardless of school location. In the few items where we observed statistically significant (probability < .05) differences based on school location, students from suburban schools were marginally favored by only a few percentage points compared to students from urban schools. In conclusion, based on our surveys results most students participating in SEFs come from suburban schools, but students participating in SEFs and coming from urban schools have equivalent SEF experiences, and very few students participating in SEFs come from rural schools.
Assuntos
Engenharia , Etnicidade , População , Grupos Raciais , Instituições Acadêmicas , Ciência , Estudantes , Humanos , Asiático , Engenharia/educação , Engenharia/estatística & dados numéricos , Etnicidade/estatística & dados numéricos , Instituições Acadêmicas/estatística & dados numéricos , Estudantes/estatística & dados numéricos , Estados Unidos/epidemiologia , Ciência/educação , Ciência/estatística & dados numéricos , População Urbana , População Suburbana , População Rural , Negro ou Afro-Americano , Brancos , Hispânico ou Latino , Grupos Raciais/etnologia , Grupos Raciais/estatística & dados numéricos , Inquéritos e Questionários , Comportamento CompetitivoRESUMO
In this paper, we report ethnicity trends in student participation and experience in high school science and engineering fair (SEFs). SEF participation showed significant ethnic diversity. For survey students, the approximate distribution was Asian-32%; Black-11%; Hispanic-20%; White-33%; Other-3%. Comparing the SEF level at which students competed from school to district to region to state levels, we observed that black students made up only 4.5% of the students who participated in SEF beyond the school level, whereas students from other ethnic groups were more equally represented at all levels. The lower percentage of Black students resulted from a combination of lower overall participation in SEF and lower percentage of those students who did participate to advance to SEFs beyond the school level. Students who advanced to SEFs beyond the school level frequently received help from scientists, coaching for the interview, and were not required to participate in SEF. Black students received the least help from scientists, were least likely to receive coaching for the interview, and were most likely to be required to participate in SEF. They also were most likely to receive no help from parents, teachers, or scientists. Asian and Hispanic students (63.8% and 56.8%) indicated a greater interest in careers in science and engineering (S&E) compared to Black and White students (43.7% & 50.7%). In addition to career interest, the most important experiences that correlated with students who indicated that SEF increased their interests in S&E were getting help from the internet, books and magazines; getting help fine tuning the report; and overcoming obstacles by doing more background research, making a timeline, and perseverance. Black students did not report a positive effect of any of these strategies but experienced time pressure as more of an obstacle than did other students. Our findings identify a wide range of student experiences associated with positive SEF outcomes that could be enhanced for all students but especially Black students. More involvement of scientists in helping students who participate in SEFs would be particularly valuable.
Assuntos
Etnicidade , Instituições Acadêmicas , Engenharia/educação , Hispânico ou Latino , Humanos , EstudantesRESUMO
Science fairs offer potential opportunities for students to learn first-hand about the practices of science. Over the past six years we have been carrying out voluntary and anonymous surveys with regional and national groups of high school and post high school students to learn about their high school science fair experiences regarding help received, obstacles encountered, and opinions about the value and impact of science fair. Understanding what students think about science fairs will help educators make science fairs more effective learning opportunities. In this paper, we focus on the findings with two national groups of post high school students-undergraduate research fellows (SURF students) who did research at UT Southwestern Medical Center during 2014-2019 and undergraduates biology students attending the 2019 Howard Hughes Medical Institute Science Education Alliance (SEA) summer symposium. About 25% of the students who completed surveys indicated that they had participated in high school science fair, but more than half attended high schools where science fairs were unavailable. Effectively, 6 out of every 10 students participated in science fair if available. Students who could have participated in high school science fair but chose not to do so identified not enough time and coming up with their project idea as major reasons why not. About half the SURF students favored requiring non-competitive science fair regardless whether they themselves had participated in science fair. On the other hand, less than 1 in 5 thought that competitive science fair should be required. Introduction to the scientific process and general learning were mentioned most frequently as the reasons to require non-competitive science fair; these reasons were mentioned rarely in connection with competitive science fair. Unlike the national cohort of high school students we surveyed previously, who mostly did science fair in 9th and 10th grades, SURF students participated in science fair throughout high school and were twice as likely as high school students to have carried out science fair more than once. In conclusion, our findings suggest that participation of the undergraduate bioscience majors in high school science fairs occurs far more frequently than recognized previously and provide insights into how these successful college students (gauged by the fact that they are doing summer science research) view science fairs. The findings emphasize further the importance of incentivizing rather than requiring science fair participation, especially in 9th and 10th grades, and the potential value of developing non-competitive science fairs.
Assuntos
Ciência/educação , Estudantes/psicologia , Feminino , Humanos , Masculino , Instituições Acadêmicas , Inquéritos e QuestionáriosRESUMO
The goal of our ongoing research is to identify strengths and weaknesses of high school level science fair and improvements that can help science educators make science fair a more effective, inclusive and equitable learning experience. In this paper, we confirm and extend our previous findings in several important ways. We added new questions to our anonymous and voluntary surveys to learn the extent to which students had an interest in science or engineering careers and if science fair participation increased their interest in science or engineering. And we surveyed a national rather than regional high school student group by incorporating our survey into the Scienteer online portal now used by Texas and some other states for science fair registration, parental consent, and project management. We learned that about ~60% of the more than 300 students in the national cohorts completing surveys in 2017 and 2018 said that they were interested in a career in science or engineering, and ~60% said that participating in science fair increased their interest in science or engineering. About two-thirds of the students were required to participate in science fair, and that requirement reduced the frequency of students who said that science fair increased their interest. In the worst case, ~10% of the students who said that they were not interested in a career in science or engineering and who were required to participate in science fair engaged in research misconduct (i.e., plagiarism and making up their results). Students' positive comments about competition in science fair focused on the competition incentive, whereas their positive comments about science fair that was non-competitive focused on learning about the scientific process and learning in general. We discuss the findings in the context of National Science Teaching Association guidance about voluntary science fair participation and begin to identify features of science fair practice consistent with increased student interest in the sciences or engineering.
Assuntos
Escolha da Profissão , Comportamento Competitivo , Aprendizagem , Psicologia Educacional , Ciência/educação , Estudantes/psicologia , Adolescente , Feminino , Humanos , Masculino , Motivação , Pesquisa Qualitativa , Instituições AcadêmicasRESUMO
The goal of our research is to identify strengths and weaknesses of high school level science fair and improvements that might enhance learning outcomes based on empirical assessment of student experiences. We use the web-based data collection program REDCap to implement anonymous and voluntary surveys about science fair experiences with two independent groups-high school students who recently competed in the Dallas Regional Science and Engineering Fair and post high school students (undergraduates, 1st year medical students, and 1st year biomedical graduate students) on STEM education tracks doing research at UT Southwestern Medical Center. Herein, we report quantitative and qualitative data showing student opinions about the value of science fair. Few students in any group thought that competitive science fair (C-SF) should be required. The most common reasons given for not requiring C-SF were no enjoyment and no interest in competing. On the other hand, student attitudes towards requiring non-competitive science fair (NC-SF) were nuanced and ranged as high as 91%, increasing with student maturation, science fair experience, and STEM track. The most common reasons given for requiring NC-SF were learning scientific thinking skills and research skills. Students opposed to requiring NC-SF most frequently mentioned no enjoyment and no interest in science. Several student comments critical of the fairness of science fair led us to determine possible differences in science fair experiences depending on whether or not students received help from scientists. Those who received help from scientists had an easier time getting their research idea, more access to articles in books and magazines, and less difficulty getting resources. We discuss the idea that two different types of science fairs-competitive science fair with a performance goal orientation and non-competitive science fair with a mastery goal orientation-might be required to promote the broad goal of educating all students about science and engineering.
Assuntos
Instituições Acadêmicas , Ciência/educação , Estudantes/psicologia , Atitude , Comportamento Competitivo , Engenharia/educação , Humanos , Pesquisa Qualitativa , Tecnologia/educaçãoRESUMO
Fibroblast migration plays a key role during various physiological and pathological processes. Although migration of individual fibroblasts has been well studied, migration in vivo often involves simultaneous locomotion of fibroblasts sited in close proximity, so-called 'en masse migration', during which intensive cell-cell interactions occur. This study aims to understand the effects of matrix mechanical environments on the cell-matrix and cell-cell interactions during en masse migration of fibroblasts on collagen matrices. Specifically, we hypothesized that a group of migrating cells can significantly deform the matrix, whose mechanical microenvironment dramatically changes compared with the undeformed state, and the alteration of the matrix microenvironment reciprocally affects cell migration. This hypothesis was tested by time-resolved measurements of cell and extracellular matrix movement during en masse migration on collagen hydrogels with varying concentrations. The results illustrated that a group of cells generates significant spatio-temporal deformation of the matrix before and during the migration. Cells on soft collagen hydrogels migrate along tortuous paths, but, as the matrix stiffness increases, cell migration patterns become aligned with each other and show coordinated migration paths. As cells migrate, the matrix is locally compressed, resulting in a locally stiffened and dense matrix across the collagen concentration range studied.
Assuntos
Movimento Celular , Microambiente Celular , Colágeno/química , Matriz Extracelular/química , Fibroblastos/metabolismo , Hidrogéis/química , Células Cultivadas , Fibroblastos/citologia , Humanos , MasculinoRESUMO
Understanding how institutional review boards/research ethics committees (IRBs/RECs) perform risk/benefit assessment is important to help improve their function. In environmental ethics, uncertainty about potential outcomes and the precautionary principle play important roles in regulatory oversight but have received little attention in the context of human research ethics. We carried out an empirical study to gain insight into uncertainty by asking IRB/REC members about confidence in their risk assessments immediately after discussion of new protocols under review. Based on 12 meetings carried out by four IRBs/RECs over a 6-month period, we found a robust, inverse relationship between risk and confidence. As risk increased, confidence decreased. We detected different patterns of consensus between different IRBs/RECs and their members. Our study introduces a novel and relatively easy to implement approach to begin to understand IRB/REC decision making in real time that can be used within or across institutions.
Assuntos
Pesquisa Biomédica/ética , Tomada de Decisões/ética , Revisão Ética , Comitês de Ética em Pesquisa , Medição de Risco , Incerteza , Revisão Ética/normas , Ética em Pesquisa , Experimentação Humana , HumanosRESUMO
The most common genetic alterations for familial thoracic aortic aneurysms and dissections (TAAD) are missense mutations in vascular smooth muscle (SM) α-actin encoded by ACTA2 We focus here on ACTA2-R258C, a recurrent mutation associated with early onset of TAAD and occlusive moyamoya-like cerebrovascular disease. Recent biochemical results with SM α-actin-R258C predicted that this variant will compromise multiple actin-dependent functions in intact cells and tissues, but a model system to measure R258C-induced effects was lacking. We describe the development of an approach to interrogate functional consequences of actin mutations in affected patient-derived cells. Primary dermal fibroblasts from R258C patients exhibited increased proliferative capacity compared with controls, consistent with inhibition of growth suppression attributed to SM α-actin. Telomerase-immortalized lines of control and R258C human dermal fibroblasts were established and SM α-actin expression induced with adenovirus encoding myocardin-related transcription factor A, a potent coactivator of ACTA2 Two-dimensional Western blotting confirmed induction of both wild-type and mutant SM α-actin in heterozygous ACTA2-R258C cells. Expression of mutant SM α-actin in heterozygous ACTA2-R258C fibroblasts abrogated the significant effects of SM α-actin induction on formation of stress fibers and focal adhesions, filamentous to soluble actin ratio, matrix contraction, and cell migration. These results demonstrate that R258C dominantly disrupts cytoskeletal functions attributed to SM α-actin in fibroblasts and are consistent with deficiencies in multiple cytoskeletal functions. Thus, cellular defects due to this ACTA2 mutation in both aortic smooth muscle cells and adventitial fibroblasts may contribute to development of TAAD and proliferative occlusive vascular disease.
Assuntos
Actinas/metabolismo , Fibroblastos/metabolismo , Mutação de Sentido Incorreto , Pele/metabolismo , Actinas/genética , Adulto , Dissecção Aórtica/genética , Aorta/metabolismo , Aneurisma da Aorta Torácica/genética , Biópsia , Domínio Catalítico , Movimento Celular , Proliferação de Células , Criança , Citoesqueleto/metabolismo , Progressão da Doença , Feminino , Humanos , Masculino , Músculo Liso/citologia , Miócitos de Músculo Liso/metabolismo , Miofibroblastos/metabolismo , Telomerase/genética , Transcrição GênicaRESUMO
Research misconduct has become an important matter of concern in the scientific community. The extent to which such behavior occurs early in science education has received little attention. In the current study, using the web-based data collection program REDCap, we obtained responses to an anonymous and voluntary survey about science fair from 65 high school students who recently competed in the Dallas Regional Science and Engineering Fair and from 237 STEM-track, post-high school students (undergraduates, 1st year medical students, and 1st year biomedical graduate students) doing research at UT Southwestern Medical Center. Of the post-high school students, 24% had competed in science fair during their high school education. Science fair experience was similar overall for the local cohort of Dallas regional students and the more diverse state/national cohort of post-high school students. Only one student out of 122 reported research misconduct, in his case making up the data. Unexpectedly, post-high school students who did not participate in science fair anticipated that carrying out science fair would be much more difficult than actually was the case, and 22% of the post-high school students anticipated that science fair participants would resort to research misconduct to overcome obstacles. No gender-based differences between students' science fair experiences or expectations were evident.
Assuntos
Pesquisa/educação , Ciência/educação , Adolescente , Educação/métodos , Engenharia/educação , Feminino , Humanos , Masculino , Instituições AcadêmicasRESUMO
Cryopreservation is one of the key enabling technologies for tissue engineering and regenerative medicine, which can provide reliable long-term storage of engineered tissues (ETs) without losing their functionality. However, it is still extremely difficult to design and develop cryopreservation protocols guaranteeing the post-thaw tissue functionality. One of the major challenges in cryopreservation is associated with the difficulty of identifying effective and less toxic cryoprotective agents (CPAs) to guarantee the post-thaw tissue functionality. In this study, thus, a hypothesis was tested that the modulation of the cytoskeletal structure of cells embedded in the extracellular matrix (ECM) can mitigate the freezing-induced changes of the functionality and can reduce the amount of CPA necessary to preserve the functionality of ETs during cryopreservation. In order to test this hypothesis, we prepared dermal equivalents by seeding fibroblasts in type I collagen matrices resulting in three different cytoskeletal structures. These ETs were exposed to various freeze/thaw (F/T) conditions with and without CPAs. The freezing-induced cell-fluid-matrix interactions and subsequent functional properties of the ETs were assessed. The results showed that the cytoskeletal structure and the use of CPA were strongly correlated to the preservation of the post-thaw functional properties. As the cytoskeletal structure became stronger via stress fiber formation, the ET's functionality was preserved better. It also reduced the necessary CPA concentration to preserve the post-thaw functionality. However, if the extent of the freezing-induced cell-fluid-matrix interaction was too excessive, the cytoskeletal structure was completely destroyed and the beneficial effects became minimal.
Assuntos
Criopreservação , Citoesqueleto/metabolismo , Fenômenos Biomecânicos , Sobrevivência Celular , Colágeno Tipo I/metabolismo , Matriz Extracelular/metabolismo , Fibroblastos/citologia , Fibroblastos/metabolismo , Humanos , Fibras de Estresse/metabolismo , Engenharia TecidualRESUMO
Formation of cell clusters is a common morphogenic cell behavior observed during tissue and organ development and homeostasis, as well as during pathological disorders. Dynamic regulation of cell clustering depends on the balance between contraction of cells into clusters and migration of cells as dispersed individuals. Previously we reported that under procontractile culture conditions, fibronectin fibrillar matrix assembly by human fibroblasts functioned as a nucleation center for cell clustering on three-dimensional collagen matrices. Here we report that switching preformed cell clusters from procontractile to promigratory culture conditions results in cell dispersal out of clusters and disruption of FN matrix. Experiments using small interfering RNA silencing and pharmacological inhibition demonstrated that matrix metalloproteinase activity involving MMP-2 was necessary for fibronectin matrix disruption and dispersal of cell clusters.
Assuntos
Colágenos Fibrilares/química , Fibroblastos/enzimologia , Fibronectinas/metabolismo , Metaloproteinase 2 da Matriz/fisiologia , Fator de Crescimento Derivado de Plaquetas/fisiologia , Agregação Celular , Linhagem Celular , Meios de Cultura/química , Matriz Extracelular/metabolismo , HumanosRESUMO
Contraction of 3D collagen matrices by fibroblasts frequently is used as an in vitro model of wound closure. Different iterations of the model - all conventionally referred to as "contraction" - involve different morphological patterns. During floating matrix contraction, cells initially are round without stress fibers and subsequently undergo spreading. During stressed matrix contraction, cells initially are spread with stress fibers and subsequently undergo shortening. In the current studies, we used siRNA silencing of myosin IIA (MyoIIA) and myosin IIB (MyoIIB) to test the roles of myosin II isoforms in fibroblast interactions with 3D collagen matrices and collagen matrix contraction. We found that MyoIIA but not MyoIIB was required for cellular global inward contractile force, formation of actin stress fibers, and morphogenic cell clustering. Stressed matrix contraction required MyoIIA but not MyoIIB. Either MyoIIA or MyoIIB was sufficient for floating matrix contraction (FMC) stimulated by platelet-derived growth factor. Neither MyoIIA or MyoIIB was necessary for FMC stimulated by serum. Our findings suggest that myosin II-dependent motor mechanisms for collagen translocation during extracellular matrix remodeling differ depending on cell tension and growth factor stimulation.
Assuntos
Fibroblastos/metabolismo , Miosina não Muscular Tipo IIA/metabolismo , Miosina não Muscular Tipo IIB/metabolismo , Fenômenos Biomecânicos , Adesão Celular/fisiologia , Agregação Celular/fisiologia , Linhagem Celular , Movimento Celular/fisiologia , Colágeno/metabolismo , Matriz Extracelular/metabolismo , Fibroblastos/citologia , Fibroblastos/efeitos dos fármacos , Compostos Heterocíclicos de 4 ou mais Anéis/farmacologia , Humanos , Miosina não Muscular Tipo IIA/antagonistas & inibidores , Miosina não Muscular Tipo IIA/genética , Miosina não Muscular Tipo IIB/antagonistas & inibidores , Miosina não Muscular Tipo IIB/genética , RNA Interferente Pequeno/genética , Cicatrização/fisiologiaRESUMO
Quite distinct regulatory measures have been established to try to deal with research misconduct and conflict of interest. To decrease research misconduct, the emphasis has been on education aimed at promoting an understanding of and commitment to research integrity. To decrease the impact of conflict of interest, the emphasis has been on management of the research environment. In this essay I discuss the idea that research misconduct and its close relative "questionable research practices" should be framed in the context of conflict of interest. If we take seriously the implication of conflict of interest regulations that even a $5,000 financial interest might bias the design, conduct, or reporting of research, then how much more risk of bias will be in play when what is at stake is ongoing funding of short-term research grants on which a researcher's salary and job depend? Education is important and necessary to promote research integrity but by itself will not be sufficient. Placing problems of research misconduct and questionable research practices in the context of conflict of interest makes it clear that we also will need to develop new approaches to manage the structure of the research environment. One example of such a management strategy would be for NIH to phase in a limit on the overall percentage of a faculty member's salary permitted to be supported with NIH grant funds, complementing the already existing upper dollar limit that can be used for faculty salaries.
RESUMO
Myocardin-related transcription factors (MRTFs) regulate cellular contractility and motility by associating with serum response factor (SRF) and activating genes involved in cytoskeletal dynamics. We reported previously that MRTF-A contributes to pathological cardiac remodeling by promoting differentiation of fibroblasts to myofibroblasts following myocardial infarction. Here, we show that forced expression of MRTF-A in dermal fibroblasts stimulates contraction of a collagen matrix, whereas contractility of MRTF-A null fibroblasts is impaired under basal conditions and in response to TGF-ß1 stimulation. We also identify an isoxazole ring-containing small molecule, previously shown to induce smooth muscle α-actin gene expression in cardiac progenitor cells, as an agonist of myofibroblast differentiation. Isoxazole stimulates myofibroblast differentiation via induction of MRTF-A-dependent gene expression. The MRTF-SRF signaling axis is activated in response to skin injury, and treatment of dermal wounds with isoxazole accelerates wound closure and suppresses the inflammatory response. These results reveal an important role for MRTF-SRF signaling in dermal myofibroblast differentiation and wound healing and suggest that targeting MRTFs pharmacologically may prove useful in treating diseases associated with inappropriate myofibroblast activity.
Assuntos
Diferenciação Celular , Derme/lesões , Derme/metabolismo , Regulação da Expressão Gênica , Miofibroblastos/metabolismo , Transativadores/metabolismo , Cicatrização , Androstenóis/farmacologia , Animais , Derme/patologia , Camundongos , Miofibroblastos/patologia , Fator de Crescimento Transformador beta1/farmacologiaAssuntos
Pesquisa Biomédica/economia , Governo Federal , Organização do Financiamento/métodos , Apoio à Pesquisa como Assunto/métodos , Pesquisa Biomédica/normas , Orçamentos/legislação & jurisprudência , Eficiência , Organização do Financiamento/economia , Organização do Financiamento/normas , Organização do Financiamento/estatística & dados numéricos , Humanos , Fator de Impacto de Revistas , National Institutes of Health (U.S.)/economia , National Institutes of Health (U.S.)/legislação & jurisprudência , Pesquisadores/economia , Apoio à Pesquisa como Assunto/economia , Apoio à Pesquisa como Assunto/legislação & jurisprudência , Salários e Benefícios/economia , Fatores de Tempo , Estados UnidosRESUMO
Fibroblast clusters have been observed in tissues under a variety of circumstances: in fibrosis and scar, in the formation of hair follicle dermal papilla, and as part of the general process of mesenchymal condensation that takes place during development. Cell clustering has been shown to depend on features of the extracellular matrix, growth factor environment, and mechanisms to stabilize cell-cell interactions. In vitro studies have shown that increasing the potential for cell-cell adhesion relative to cell-substrate adhesion promotes cell clustering. Experimental models to study fibroblast clustering have utilized centrifugation, hanging drops, and substrata with poorly adhesive, soft and mechanically unstable properties. In this review, we summarize work on a new, highly tractable, cell clustering research model in which human fibroblasts are incubated on the surfaces of collagen matrices. Fibroblast clustering occurs under procontractile growth factor conditions (e.g., serum or the serum lipid agonist lysophosphatidic acid) but not under promigratory growth factor conditions (e.g., platelet-derived growth factor) and can be reversed by switching growth factor environments. Cell contraction plays a dual role in clustering to bring cells closer together and to stimulate cells to organize fibronectin into a fibrillar matrix. Binding of fibroblasts to a shared fibronectin fibrillar matrix stabilizes clusters, and fragmentation of the fibrillar matrix occurs when growth factor conditions are switched to promote cell dispersal.
Assuntos
Movimento Celular , Matriz Extracelular/metabolismo , Fibroblastos/citologia , Animais , Adesão Celular/fisiologia , Colágeno/química , Colágeno/metabolismo , Fibroblastos/metabolismo , HumanosRESUMO
Science traditionally is taught as a linear process based on logic and carried out by objective researchers following the scientific method. Practice of science is a far more nuanced enterprise, one in which intuition and passion become just as important as objectivity and logic. Whether the activity is committing to study a particular research problem, drawing conclusions about a hypothesis under investigation, choosing whether to count results as data or experimental noise, or deciding what information to present in a research paper, ethical challenges inevitably will arise because of the ambiguities inherent in practice. Unless these ambiguities are acknowledged and their sources understood explicitly, responsible conduct of science education will not adequately prepare the individuals receiving the training for the kinds of decisions essential to research integrity that they will have to make as scientists.