2,114 research outputs found
Supporting Drama in Education: Developing a Professional Resource
This research offers an examination of the application of a resource to support Drama in Education (DiE) as a teaching tool. The scope of this small-scale, qualitative research was two-fold: i) to develop a teacher resource; and ii) to study its effectiveness in supporting teachers. My goal was to explore the experiences of professionals to see if the resource I created was effective in developing teacher confidence in integrating drama-based methodology into their regular programming. The research undergoes three phases: i) the formulation of the professional resource, ii) field-testing of the resource and data collection, and iii) data analysis with the final stage being modification of the resource. Based on the data collected from semi-open-ended interviews with two elementary teachers, and personal notes shared by the participant teachers, there appears to be clear evidence the resource is effective in developing educator confidence. The research also offers various implications for teachers and administrators, school boards, and other research in DiE
Progress in customer relationship management adoption: a cross-sector study
Although customer relationship management (CRM) is widely used by organizations to capture and manage customer data, the process of implementation can be problematic. This article takes a multi-sector view of CRM implementation in three areas of the UK services sector: banking and finance; professional services; and the government/public sector. The study captures variations in CRM practice and implementation across these sectors, applying an existing framework of CRM implementation to tease out progress in relation to people (the company's staff), the company itself, the customers, and the technology. The implications for organizations that have reached different implementation stages in their CRM journey are considered
Characterization of tetracycline modifying enzymes using a sensitive in vivo reporter system
Abstract
Background
Increasing our understanding of antibiotic resistance mechanisms is critical. To enable progress in this area, methods to rapidly identify and characterize antibiotic resistance conferring enzymes are required.
Results
We have constructed a sensitive reporter system in Escherichia coli that can be used to detect and characterize the activity of enzymes that act upon the antibiotic, tetracycline and its derivatives. In this system, expression of the lux operon is regulated by the tetracycline repressor, TetR, which is expressed from the same plasmid under the control of an arabinose-inducible promoter. Addition of very low concentrations of tetracycline derivatives, well below growth inhibitory concentrations, resulted in luminescence production as a result of expression of the lux genes carried by the reporter plasmid. Introduction of another plasmid into this system expressing TetX, a tetracycline-inactivating enzyme, caused a marked loss in luminescence due to enzyme-mediated reduction in the intracellular Tc concentration. Data generated for the TetX enzyme using the reporter system could be effectively fit with the known Km and kcat values, demonstrating the usefulness of this system for quantitative analyses.
Conclusion
Since members of the TetR family of repressors regulate enzymes and pumps acting upon almost every known antibiotic and a wide range of other small molecules, reporter systems with the same design as presented here, but employing heterologous TetR-related proteins, could be developed to measure enzymatic activities against a wide range of antibiotics and other compounds. Thus, the assay described here has far-reaching applicability and could be adapted for high-throughput applications
Analyzing web server performance under dynamic user workloads
The increasing popularity of web applications has introduced a new paradigm where users are no longer passive web consumers but they become active contributors to the web, specially in the contexts of social networking, blogs, wikis or e-commerce. In this new paradigm, contents and services are even more dynamic, which consequently increases the level of dynamism in user's behavior. Moreover, this trend is expected to rise in the incoming web. This dynamism is a major adversity to define and model representative web workload, in fact, this characteristic is not fully represented in the most of the current web workload generators. This work proves that the web user's dynamic behavior is a crucial point that must be addressed in web performance studies in order to accurately estimate system performance indexes. In this paper, we analyze the effect of using a more realistic dynamic workload on the web performance metrics. To this end, we evaluate a typical e-commerce scenario and compare the results obtained using different levels of dynamic workload instead of traditional workloads. Experimental results show that, when a more dynamic and interactive workload is taken into account, performance indexes can widely differ and noticeably affect the stress borderline on the server. For instance, the processor usage can increase 30% due to dynamism, affecting negatively average response time perceived by users, which can also turn in unwanted effects in marketing and fidelity policies. © 2012 Elsevier B.V. All rights reserved.This work has been partially supported by the Spanish Ministry of Science and Innovation under Grant TIN-2009-08201.Peña Ortiz, R.; Gil Salinas, JA.; Sahuquillo Borrás, J.; Pont Sanjuan, A. (2013). Analyzing web server performance under dynamic user workloads. Computer Communications. 36(4):386-395. https://doi.org/10.1016/j.comcom.2012.11.005S38639536
Parameter identifiability in PDE models of fluorescence recovery after photobleaching
Identifying unique parameters for mathematical models describing biological
data can be challenging and often impossible. Parameter identifiability for
partial differential equations models in cell biology is especially difficult
given that many established \textit{in vivo} measurements of protein dynamics
average out the spatial dimensions. Here, we are motivated by recent
experiments on the binding dynamics of the RNA-binding protein PTBP3 in RNP
granules of frog oocytes based on fluorescence recovery after photobleaching
(FRAP) measurements. FRAP is a widely-used experimental technique for probing
protein dynamics in living cells, and is often modeled using simple
reaction-diffusion models of the protein dynamics. We show that current methods
of structural and practical parameter identifiability provide limited insights
into identifiability of kinetic parameters for these PDE models and
spatially-averaged FRAP data. We thus propose a pipeline for assessing
parameter identifiability and for learning parameter combinations based on
re-parametrization and profile likelihoods analysis. We show that this method
is able to recover parameter combinations for synthetic FRAP datasets and
investigate its application to real experimental data.Comment: 19 pages, 10 figure
Indomethacin-induced G1/S phase arrest of the plant cell cycle
AbstractIn animal systems, indomethacin inhibits cAMP production via a prostaglandin-adenylyl cyclase pathway. To examine the possibility that a similar mechanism occurs in plants, the effect of indomethacin on the cell cycle of a tobacco bright yellow 2 (TBY-2) cell suspension was studied. Application of indomethacin during mitosis did not interfere with the M/G1 progression in synchronized BY-2 cells but it inhibited cAMP production at the beginning of the G1 phase and arrested the cell cycle progression at G1/S. These observations are discussed in relation to the putative involvement of cAMP biosynthesis in the cell cycle progression in TBY-2 cells
ROS-related redox regulation and signaling in plants
As sessile oxygenic organisms with a plastic developmental programme, plants are uniquely positioned to exploit reactive oxygen species (ROS) as powerful signals. Plants harbor numerous ROS-generating pathways, and these oxidants and related redox-active compounds have become tightly embedded into plant function and development during the course of evolution. One dominant view of ROS-removing systems sees them as beneficial antioxidants battling to keep damaging ROS below dangerous levels. However, it is now established that ROS are a necessary part of subcellular and intercellular communication in plants and that some of their signaling functions require ROS-metabolizing systems. For these reasons, it is suggested that “ROS processing systems” would be a more accurate term than “antioxidative systems” to describe cellular components that are most likely to interact with ROS and, in doing so, transmit oxidative signals. Within this framework, our update provides an overview of the complexity and compartmentation of ROS production and removal. We place particular emphasis on the importance of ROS-interacting systems such as the complex cellular thiol network in the redox regulation of phytohormone signaling pathways that are crucial for plant development and defense against external threats
Study on Chinese Tourism Web Sites' Distribution and Online Marketing Effects.
As a platform and carrier of tourism information, tourism websites (TWs) and online tourism marketing have deeply affected the tourism industry. The authors adopt a geographical perspective to analyze the distribution of Chinese tourism websites (CTWs), and statistical analysis with SPSS16.0 was conducted to explore the online marketing effects of CTWs, and some meaningful results has been produced: 1) The number of CTWs generally decreases from eastern China to central and western China, and are especially dominant in tourism developed provinces. 2) The number of tourists has strong statistical correlation with the number of CTWs. 3) The strongest correlation for inbound tourists is with hotel websites, and the highest correlation coefficient is 0.807 between the number of domestic tourist and resort websites. Both inbound and domestic tourists have a low correlation coefficient with travel agency websites (TA). 4) There exist some statistical models between tourist numbers and different kinds of CTWs. The results clearly unveil the marketing effects and correlation of CTWs and is helpful for further online marketing strategies
The Lack of Mitochondrial Thioredoxin TRXo1 Affects In Vivo Alternative Oxidase Activity and Carbon Metabolism under Different Light Conditions
International audienceThe alternative oxidase (AOX) constitutes a nonphosphorylating pathway of electron transport in the mitochondrial respiratory chain that provides flexibility to energy and carbon primary metabolism. Its activity is regulated in vitro by the mitochondrial thioredoxin (TRX) system which reduces conserved cysteines residues of AOX. However, in vivo evidence for redox regulation of the AOX activity is still scarce. In the present study, the redox state, protein levels and in vivo activity of the AOX in parallel to photosynthetic parameters were determined in Arabidopsis knockout mutants lacking mitochondrial trxo1 under moderate (ML) and high light (HL) conditions, known to induce in vivo AOX activity. In addition, 13C- and 14C-labeling experiments together with metabolite profiling were performed to better understand the metabolic coordination between energy and carbon metabolism in the trxo1 mutants. Our results show that the in vivo AOX activity is higher in the trxo1 mutants at ML while the AOX redox state is apparently unaltered. These results suggest that mitochondrial thiol redox systems are responsible for maintaining AOX in its reduced form rather than regulating its activity in vivo. Moreover, the negative regulation of the tricarboxylic acid cycle by the TRX system is coordinated with the increased input of electrons into the AOX pathway. Under HL conditions, while AOX and photosynthesis displayed similar patterns in the mutants, photorespiration is restricted at the level of glycine decarboxylation most likely as a consequence of redox imbalance
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