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1.
CBE Life Sci Educ ; 15(3)2016.
Artículo en Inglés | MEDLINE | ID: mdl-27587851

RESUMEN

The National Institute of Food and Agriculture within the U.S. Department of Agriculture provides leadership, capacity, and funds to support the continuing development of a safe and competitive agricultural system. Many of the agency's educational programs are led by the Division of Community and Education (DOCE). These programs span agricultural education, enhancing agricultural literacy through both formal and nonformal education. Here, we have highlighted funding opportunities within DOCE that enhance agricultural education and literacy by supporting the improvement of students' critical communication, leadership skills, and experiential learning opportunities. Some of these programs include opportunities for which students can apply, while others focus on faculty applications. Opportunities faculty can apply for may support student-recruitment and student-retention techniques, curriculum development, innovative teaching methods, and institutional capacity-building programs. Overall, these programs foster a diverse workforce in agricultural science that matches the increasing diversity of the country.


Asunto(s)
Agricultura/educación , Financiación del Capital , Alimentos , Recursos Naturales , Ciencias Sociales/educación , Creación de Capacidad , Becas , Humanos , Grupos Minoritarios , Desarrollo de Programa , Estados Unidos , United States Department of Agriculture
2.
Environ Entomol ; 45(5): 1227-1234, 2016 10.
Artículo en Inglés | MEDLINE | ID: mdl-27550164

RESUMEN

The brown marmorated stink bug, Halyomorpha halys (Stål), is an invasive pest from Asia that feeds on many agricultural crops in the United States, including blueberries. Yet, the effects of H. halys feeding on fruit chemistry and induced resistance to insects remain unknown. Here we hypothesized that frugivory by H. halys changes fruit chemical composition, which in turn affects insect feeding behavior. In field experiments, blueberry fruit was either mechanically injured or injured by 0 (control), 2, 5, or 10 H. halys Total soluble solids (°Brix) and anthocyanin and phenolic content in injured and uninjured fruits, as well as their effects on feeding behavior by conspecifics, were measured subsequently in the laboratory. Results showed lower °Brix values in injured fruit as compared with uninjured fruit. Fruit injured by 2 and 5 H. halys also had 32 and 20% higher total phenolics, respectively, than the uninjured controls. The proportions of the anthocyanins derived from delphinidin, cyanidin, and petunidin increased, whereas those from malvidin decreased, in fruit after mechanical wounding and frugivory by H. halys In dual-choice tests, H. halys fed more often on uninjured fruit than those previously injured by conspecifics. These results show that frugivory by H. halys reduces the amounts of soluble solids, alters anthocyanin ratios, and increases levels of phenolics, and, as a result, injured fruits were a less preferred food source for conspecifics. To our knowledge, this is the first study to investigate the effects of frugivory on fruit chemistry and induced fruit resistance against a fruit-eating herbivore.


Asunto(s)
Arándanos Azules (Planta)/química , Herbivoria , Heterópteros/fisiología , Animales , Conducta Alimentaria , Femenino , Preferencias Alimentarias , Frutas/química , Heterópteros/crecimiento & desarrollo , Masculino , Ninfa/crecimiento & desarrollo , Ninfa/fisiología
3.
J Econ Entomol ; 108(3): 1156-63, 2015 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-26470241

RESUMEN

Brown marmorated stink bug, Halyomorpha halys (Stål) (Hemiptera: Pentatomidae), is a severe economic pest of growing importance in the United States, Canada, and Europe. While feeding damage from H. halys has been characterized in tree fruit, vegetables, and agronomic crops, less is known about the impacts of stink bugs on small fruits such as blueberries. In this study, we examined H. halys feeding on two representative early and late ripening blueberry cultivars in Oregon and New Jersey. This research examined how different densities of H. halys confined on blueberry clusters for week-long periods affected fruit quality at harvest. After fruit were ripe, we stained and quantified the number of salivary sheaths on berries as an indication of feeding pressure. Feeding by H. halys damaged the fruits by causing increased levels of external discoloration, and internal damage in the form of tissue necrosis. Exposure of berries to H. halys was also associated with decreasing berry weights and lower soluble solids in fruits. However, the different cultivars did not respond consistently to feeding pressure from H. halys. Weekly variability in feeding pressure of two of the cultivars as quantified by the number of stylet sheaths per berry was largely accounted for by environmental variables. We conclude that H. halys does have potential to severely damage blueberries and may become an important economic pest. Characterization of damage is important because correct identification of insect damage is key for successful management.


Asunto(s)
Arándanos Azules (Planta)/fisiología , Cadena Alimentaria , Hemípteros/fisiología , Animales , Arándanos Azules (Planta)/crecimiento & desarrollo , Productos Agrícolas/crecimiento & desarrollo , Productos Agrícolas/fisiología , Conducta Alimentaria , Hemípteros/crecimiento & desarrollo , New Jersey , Ninfa/crecimiento & desarrollo , Ninfa/fisiología , Oregon
4.
J Am Coll Health ; 63(6): 343-52, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25942068

RESUMEN

OBJECTIVE: This study examined the effects of a single-session motivational interviewing-based in-person brief alcohol intervention that contained student-athlete-specific personalized drinking feedback. PARTICIPANTS: Participants were 170 National Collegiate Athletic Association Division I student-athletes meeting screening criteria for heavy episodic drinking. METHODS: Baseline assessments of alcohol use frequency and quantity, norm perceptions of peers' alcohol use, experiences of negative consequences, and use of protective behaviors were administered to student-athletes prior to a 1-session brief intervention containing personalized feedback highlighting the relationship between alcohol use and athletic performance. Follow-up assessment was conducted 3 months post intervention. RESULTS: Student-athletes participating in the athlete-specific brief intervention showed significant reductions in their alcohol use and alcohol-related negative consequences, increases in use of protective behavioral strategies, and corrections in norm misperceptions at 3 months post intervention relative to a no-treatment comparison group. CONCLUSIONS: Student-athlete-specific brief alcohol interventions show promise in addressing high-risk drinking, reducing associated harms, and supporting health.


Asunto(s)
Atletas/psicología , Consumo Excesivo de Bebidas Alcohólicas/prevención & control , Terapia Cognitivo-Conductual/métodos , Estudiantes/psicología , Adolescente , Análisis de Varianza , Atletas/estadística & datos numéricos , Consumo Excesivo de Bebidas Alcohólicas/epidemiología , Consumo Excesivo de Bebidas Alcohólicas/psicología , Femenino , Humanos , Internet , Masculino , Entrevista Motivacional/métodos , New England/epidemiología , Evaluación de Procesos y Resultados en Atención de Salud , Grupo Paritario , Normas Sociales , Estudiantes/estadística & datos numéricos , Encuestas y Cuestionarios , Universidades , Adulto Joven
5.
CBE Life Sci Educ ; 11(1): 47-57, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22383617

RESUMEN

We present a diagnostic question cluster (DQC) that assesses undergraduates' thinking about photosynthesis. This assessment tool is not designed to identify individual misconceptions. Rather, it is focused on students' abilities to apply basic concepts about photosynthesis by reasoning with a coordinated set of practices based on a few scientific principles: conservation of matter, conservation of energy, and the hierarchical nature of biological systems. Data on students' responses to the cluster items and uses of some of the questions in multiple-choice, multiple-true/false, and essay formats are compared. A cross-over study indicates that the multiple-true/false format shows promise as a machine-gradable format that identifies students who have a mixture of accurate and inaccurate ideas. In addition, interviews with students about their choices on three multiple-choice questions reveal the fragility of students' understanding. Collectively, the data show that many undergraduates lack both a basic understanding of the role of photosynthesis in plant metabolism and the ability to reason with scientific principles when learning new content. Implications for instruction are discussed.


Asunto(s)
Biología/educación , Evaluación Educacional/métodos , Fotosíntesis , Comprensión , Femenino , Humanos , Masculino , Estudiantes , Enseñanza/métodos
6.
CBE Life Sci Educ ; 9(4): 441-52, 2010.
Artículo en Inglés | MEDLINE | ID: mdl-21123691

RESUMEN

Recent science education reform has been marked by a shift away from a focus on facts toward deep, rich, conceptual understanding. This requires assessment that also focuses on conceptual understanding rather than recall of facts. This study outlines our development of a new assessment framework and tool-a taxonomy- which, unlike existing frameworks and tools, is grounded firmly in a framework that considers the critical role that models play in science. It also provides instructors a resource for assessing students' ability to reason about models that are central to the organization of key scientific concepts. We describe preliminary data arising from the application of our tool to exam questions used by instructors of a large-enrollment cell and molecular biology course over a 5-yr period during which time our framework and the assessment tool were increasingly used. Students were increasingly able to describe and manipulate models of the processes and systems being studied in this course as measured by assessment items. However, their ability to apply these models in new contexts did not improve. Finally, we discuss the implications of our results and the future directions for our research.


Asunto(s)
Biología Celular/educación , Evaluación Educacional/métodos , Estudiantes , Enseñanza/métodos , Biología Molecular/educación , Ciencia/educación
7.
CBE Life Sci Educ ; 5(4): 323-31, 2006.
Artículo en Inglés | MEDLINE | ID: mdl-17146039

RESUMEN

College-level biology courses contain many complex processes that are often taught and learned as detailed narratives. These processes can be better understood by perceiving them as dynamic systems that are governed by common fundamental principles. Conservation of matter is such a principle, and thus tracing matter is an essential step in learning to reason about biological processes. We present here multiple-choice questions that measure students' ability and inclination to trace matter through photosynthesis and cellular respiration. Data associated with each question come from students in a large undergraduate biology course that was undergoing a shift in instructional strategy toward making fundamental principles (such as tracing matter) a central theme. We also present findings from interviews with students in the course. Our data indicate that 1) many students are not using tracing matter as a tool to reason about biological processes, 2) students have particular difficulties tracing matter between systems and have a persistent tendency to interconvert matter and energy, and 3) instructional changes seem to be effective in promoting application of the tracing matter principle. Using these items as diagnostic tools allows instructors to be proactive in addressing students' misconceptions and ineffective reasoning.


Asunto(s)
Biología/educación , Fenómenos Fisiológicos Celulares , Aprendizaje Basado en Problemas/métodos , Estudiantes , Animales , Respiración de la Célula/fisiología , Toma de Decisiones , Metabolismo Energético/fisiología , Humanos , Fotosíntesis/fisiología , Fenómenos Fisiológicos de las Plantas , Enseñanza/métodos , Universidades
8.
Biochem Mol Biol Educ ; 32(1): 20-6, 2004 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-21706683

RESUMEN

We developed web-based modules addressing fundamental concepts of introductory biology delivered through the LON-CAPA course management system. These modules were designed and used to supplement large, lecture-based introductory biology classes. Incorporating educational principles and the strength of web-based instructional technology, choices were made about knowledge presentation, representation, and construction (W. A. Nelson, D. B. Palumbo (1992) J. Educ. Media Hypermedia 1, 287-299). Knowledge presentation focused on big and connecting ideas. Knowledge representation provided students the opportunity to interact with concepts in several ways using multiple representations. For knowledge construction, we facilitated students' active and meaningful interactions with content using interwoven high-level questions. Students' extended responses to a questionnaire indicated that these modules influenced the students learning in meaningful ways. (For access to demonstration modules, go to demo.lon-capa.org/cgi-bin/signon.pl?hhmi.).

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