On-chip microelectrode impedance analysis of mammalian cell viability during biomanufacturing     

Rachita Sharma  Tobias Blackburn  Weiwei Hu  Kelly Wiltberger  Orlin D. Velev 《Biomicrofluidics》2014,8(5)

The characterization of cell viability is a challenging task in applied biotechnology, as no clear definition of cell death exists. Cell death is accompanied with a change in the electrical properties of the membrane as well as the cell interior. Therefore, changes in the physiology of cells can be characterized by monitoring of their dielectric properties. We correlated the dielectric properties of industrially used mammalian cells, sedimented over interdigitated microelectrodes, to the AC signal response across the chip. The voltage waveforms across the electrodes were processed to obtain the circuit impedance, which was used to quantify the changes in cell viability. We observed an initial decrease in impedance, after which it remained nearly constant. The results were compared with data from the dye exclusion viability test, the cell specific oxygen uptake rate, and the online viable cell density data from capacitance probes. The microelectrode technique was found to be sensitive to physiological changes taking place inside the cells before their membrane integrity is compromised. Such accurate determination of the metabolic status during this initial period, which turned out to be less well captured in the dye exclusion tests, may be essential for several biotechnology operations.  相似文献   

The use of query suggestions during information search     

Xi Niu  Diane Kelly 《Information processing & management》2014

Query suggestion is a common feature of many information search systems. While much research has been conducted about how to generate suggestions, fewer studies have been conducted about how people interact with and use suggestions. The purpose of this paper is to investigate how and when people integrate query suggestions into their searches and the outcome of this usage. The paper further investigates the relationships between search expertise, topic difficulty, and temporal segment of the search and query suggestion usage. A secondary analysis of data was conducted using data collected in a previous controlled laboratory study. In this previous study, 23 undergraduate research participants used an experimental search system with query suggestions to conduct four topic searches. Results showed that participants integrated the suggestions into their searching fairly quickly and that participants with less search expertise used more suggestions and saved more documents. Participants also used more suggestions towards the end of their searches and when searching for more difficult topics. These results show that query suggestion can provide support in situations where people have less search expertise, greater difficulty searching and at specific times during the search.  相似文献   

Perfecting Lessons Learned for Criminal Justice Online Graduate Education: Reflection,Integration, and Application     

Frances Bernat  Kelly Frailing 《Journal of Criminal Justice Education》2015,26(3):330-353

Criminal justice programs are seeing an increase in the number of online classes both at the graduate and undergraduate levels. At the graduate level, criminal justice online education requires students to achieve mastery of higher ordered thinking and advanced analytic skills. Some students may believe that online education is simply a matter of reading postings and writing simple responses to queries. In order to counter the view that modern online courses, particularly those at the graduate level, are not academic enough, online graduate faculty must find ways to engage students through useful course design and meaningful assessments that promote deep learning. Such engagement requires faculty and students to show reflection in design as well as the integration and application of course materials in a consistent and significant way. This paper will discuss our attempts to reframe graduate criminal justice online classes in order to enhance student engagement and, ultimately, their deeper learning.  相似文献   

The role of transnational networking for higher education academics     

Kelly Wakefield 《高等教育研究与发展》2015,34(6):1281-1296

Amidst rapid socio-economic change, higher education (HE) academics across the world face major challenges to its organisation, finance and management. This paper discusses the role of transnational networking in higher education. Data from 40 interviews with geographically distributed academics engaged in learning and teaching transnational networks (TNNs) were analysed. The findings show that in an increasingly globalised higher education system, transnational networking goes beyond conference attendance to entail multiple combinations of offline and online activities. We do not think that current concepts of communities of practice or networks of practice accurately describe these phenomena. Instead, we suggest that these activities entail different and varying levels of tangibility, more accurately defined by us as TNNs. Moreover, we argue that the term ‘network’ in this context facilitates the individualistic pursuit of a career increasingly essential in a pressurised higher education environment.  相似文献   

ect Cornerstone     

Kelly L. Unger 《TechTrends》2011,55(6):8-9

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Adolescents’ sleep and adjustment: Reciprocal effects     

Ryan J. Kelly  Megan M. Zeringue  Mona El-Sheikh 《Child development》2022,93(2):540-555

Reciprocal relations between sleep and adjustment were investigated. Participants included 246 adolescents (M = 15.80 years; 67.5% White, 32.5% Black/African American; 53% female, 47% male) at Time 1 (data collected 2012–2013), 227 at Time 2 (M = 16.78 years) and 215 at Time 3 (M = 17.70 years). Sleep–wake variables were measured with self-reports (sleepiness) and actigraphy (average sleep minutes and efficiency, variability in sleep minutes and efficiency). Adolescents reported on depression and anxiety symptoms, and parents reported on externalizing problems. Greater variability in sleep duration and efficiency as well as sleepiness predicted adjustment problems (range of R²: 36%–60%). Reciprocal relations were supported mostly for sleepiness (range of R²: 16%–32%). Results help understand bidirectional relations between sleep and adjustment.  相似文献   

Spatial thinking in science,technology, engineering,and mathematics: Elementary teachers' beliefs,perceptions, and self-efficacy     

Kristin Michod Gagnier  Steven J. Holochwost  Kelly R. Fisher 《科学教学研究杂志》2022,59(1):95-126

Fostering students' spatial thinking skills holds great promise for improving Science, Technology, Engineering, and Mathematics (STEM) education. Recent efforts have focused on the development of classroom interventions to build students' spatial skills, yet these interventions will be implemented by teachers, and their beliefs and perceptions about spatial thinking influence the effectiveness of such interventions. However, our understanding of elementary school teachers' beliefs and perceptions around spatial thinking and STEM is in its infancy. Thus, we created novel measures to survey elementary teachers' anxiety in solving spatial problems, beliefs in the importance of spatial thinking skills for students' academic success, and self-efficacy in cultivating students' spatial skills during science instruction. All measures exhibited high internal consistency and showed that elementary teachers experience low anxiety when solving spatial problems and feel strongly that their skills can improve with practice. Teachers were able to identify educational problems that rely on spatial problem-solving and believed that spatial skills are more important for older compared to younger students. Despite reporting high efficacy in their general teaching and science teaching, teachers reported significantly lower efficacy in their capacities to cultivate students' spatial skills during science instruction. Results were fairly consistent across teacher characteristics (e.g., years of experience and teaching role as generalist or specialist) with the exception that only years of teaching science was related to teachers' efficacy in cultivating students' spatial thinking skills during science instruction. Results are discussed within the broader context of teacher beliefs, self-efficacy, and implications for professional development research.  相似文献   

Nonsuicidal Self-Injury on Instagram: Examining Hashtag Trends     

Giordano  Amanda L.  Lundeen  Lindsay A.  Wester  Kelly L.  Lee  Jaewoo  Vickers  Samuel  Schmit  Michael K.  Kim  In Kee 《International journal for the advancement of counseling》2022,44(1):1-16

International Journal for the Advancement of Counselling - We sought to investigate how individuals who upload nonsuicidal self-injury (NSSI) content on Instagram conceptualize self-injury by...  相似文献   

High-Quality Formative Writing Assessment for Middle School Students in Tier 2 Literacy Interventions     

Deborah K Reed  Kelly Binning  Emily A. Jemison  Nicole DeSalle 《Learning disabilities research & practice》2023,38(1):70-79

Increased expectations for writing performance have created a need for formative writing assessments that will help middle school teachers better understand adolescents’ grade-appropriate writing skills and monitor the progress of students with or at risk for writing disabilities. In this practice piece, we first explain research-based recommendations for high-quality writing prompts that are interesting to students, provide clear directions, and ensure accessibility and fairness. Then, we use lessons learned from working with adolescents in Tier 2 literacy intervention classes to demonstrate how teachers can apply the recommendations to identify or develop prompts that will encourage students to write responses. In addition, we explain how analytic rubrics may be used to evaluate responses as a means of informing instruction and further refining the prompts.  相似文献   

A Meta-Analysis of Interventions to Improve Reading Comprehension Outcomes for Adolescents with Reading Difficulties     

Hyojong Sohn  Kelly Acosta  Mary T. Brownell  Nicholas A. Gage  Eilish Tompson  Carolyn Pudvah 《Learning disabilities research & practice》2023,38(2):85-103

This meta-analysis synthesized 97 effect sizes extracted from 37 intervention studies for students with reading difficulties (RDs) in Grades 6 to 12 published between 1982 and 2021 to identify the overall impact of reading interventions and the moderating effects of intervention characteristics and study design characteristics. Random-effects robust variance estimation (RVE) was used to account for dependencies within studies. Overall, interventions designed to improve reading comprehension outcomes for adolescents with RDs were effective (g = 0.63). Meta-regression analyses identified several significant moderators that were associated with intervention efficacy, such as text content, duration of intervention, agent of intervention, status of student, type of dependent measure, and study quality. We provide study limitations as well as implications for research and practice.  相似文献