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An approach to generate mimics of phosphorylated serine proteins chemically through site-specific sulfonation of cysteine is presented. This chemical modification is reversible in the presence of reducing agent and therefore is analogous to the kinase/phosphatase system used in nature. 相似文献
203.
Vallejos S Stoycheva T Umek P Navio C Snyders R Bittencourt C Llobet E Blackman C Moniz S Correig X 《Chemical communications (Cambridge, England)》2011,47(1):565-567
A new method of synthesising nanoparticle-functionalised nanostructured materials via Aerosol Assisted Chemical Vapour Deposition (AACVD) has been developed. Co-deposition of Au nanoparticles with WO(3) nanoneedles has been used to deposit a sensing layer directly onto gas sensor substrates providing devices with a six-fold increase in response to low concentrations of a test analyte (ethanol). 相似文献
204.
Assessing the Impact of a Research‐Based STEM Program on STEM Majors' Attitudes and Beliefs
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Tracy Huziak‐Clark Toni Sondergeld Moira van Staaden Christine Knaggs Anne Bullerjahn 《School science and mathematics》2015,115(5):226-236
The Science, Engineering, and Technology Gateway of Ohio (SETGO) program has a three‐pronged approach to meeting the needs at different levels of students in the science, technology, engineering, and mathematics (STEM) pipeline. The SETGO program was an extensive collaboration between a two‐year community college and a nearby four‐year institution. Two of these approaches, the STEM Summer Research Program and Owens Ready Bridge, have been found to be effective in significantly increasing participants' beliefs and attitudes for both males and females. Participants cite integrative learning activities, mentoring, and small group interactions as some reasons for their growth. This study utilized a mixed‐method approach to better understand the reasons for participant and program success. After five years of evaluation of the SETGO program, findings suggest that students feel more confident not only in their preparation for the rigors of a STEM degree, but also in their decisions to complete the degree. 相似文献
205.
Science as a Learner and as a Teacher: Measuring Science Self‐Efficacy of Elementary Preservice Teachers
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Academic science achievement of U.S. students has raised concerns regarding our ability as a nation to compete in a global economy. Additionally, research has shown that many elementary teachers have weak science content backgrounds and had poor/negative experiences as students of science, resulting in a lack of confidence regarding teaching science. However, efforts to increase science self‐efficacy (SE) in preservice teachers can help to combat these issues. This study looked at a sample of preservice elementary teachers engaged in a semester‐long science content course, using Bandura's concept of SE as a conceptual framework. Our quantitative data showed significant increases in science SE on both subscales (personal efficacy and outcome expectancy). Our qualitative data showed that students communicated an increased sense of confidence with regard to the discipline of science. In addition, students reported learning science pedagogy through the instructor's modeling. Combining our findings resulted in several meta‐inferences, one of which showed students growing as both confident learners of science and teachers of science simultaneously. We created a construct new to the literature to describe this phenomenon: “teacher‐learner,” for students are both learning science and learning to teach science simultaneously through the content course experience, resulting in increased science SE. 相似文献
206.
Juliana Utley Toni Ivey Rebekah Hammack Karen High 《School science and mathematics》2019,119(4):203-212
The Next Generation Science Standards emphasizes the inclusion of engineering practices throughout the K–12 science curriculum. Therefore, elementary educators need to be knowledgeable about engineering and engineering careers so that they can expose their students to engineering. The purpose of this study was to examine the effect of engineering professional development on in‐service elementary teachers’: (a) knowledge and perceptions regarding engineering, and (b) self‐efficacy of teaching engineering. This quantitative study revealed that even one professional development opportunity can help to alleviate some misconceptions about the work of engineers and what constitutes technology, as well as increase teachers’ confidence to teach engineering concepts. 相似文献
207.
In response to the call for more rigorously validated educational assessments, this study used an iterative multimethod validation process to develop and validate outcomes from the 21st Century Skills Assessment global rating scale. Qualitative and quantitative data sources were used to inform four types of validity evidence: content, response process, internal structure, and consequential. STEM experts and typical assessment users provided support for content, response process, and consequential validity evidence through focus group interviews and cognitive interviews. Psychometric findings suggest strong internal validity evidence for the assessment through high measures of internal consistency reliability, intra‐rater agreement, and test–retest reliability measures. 相似文献
208.