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A Field Follow-Up Study of Beginning Elementary Teachers
The present study was made to determine the relationship between the level of teaching effectiveness of beginning elementary teachers and three individual characteristics of prospective teachers. A secondary purpose was an attempt to improve the service rendered by the School of Education at North Texas State College, Denton, Texas, in the selection and guidance of students who indicate a desire to enter the program for preparing elementary teachers
Simplified models for heating system optimisation using a thermal-electrical analogy
The well-known electrical analogy for thermal modelling is based on the observation that Fourier's equation for one dimensional heat transfer takes the same form as Ohm's law. This provides a system for creating and resolving complex heat transfer problems using an established set of physically-based laws. The present article illustrates the concept for adjacent rooms in a modern university building, and investigates some of the modelling issues involved. The electrical analogy is chosen so that the models can be extended and used for future research into demand-side control of multiple buildings on the university network, requiring a fast computation time. For illustrative purposes, the present article is limited to a relatively straightforward two-room system, for which the modelling equations are conveniently represented and solved using MATLAB-SIMULINK. The coefficients of this model are estimated from data using standard nonlinear optimisation tools. For comparison, the article also develops an equivalent multiple-input Transfer Function form of the model. Finally, suggestions are made for the inclusion of occupancy estimates in the model
Models for heating system optimisation
Heating, Ventilation and Air Conditioning (HVAC) systems generally have high energy requirements, hence there is considerable interest in the development of modelling techniques, optimisation tools and micro-climate control algorithms for buildings. Pertinent to this research area is the Lancaster University Main Campus, for which a central energy centre supplies the hot water used to heat around 50% of the buildings. The Building Management System provides an abundance of energy data for the entire campus, which is further enhanced by the availability of data from the Hazelrigg weather station. This project concerns the development simple, flexible models suitable for improving control system robustness and overall system optimisation. Lancaster's energy centre provides multiple methods of heat production, such as gas boilers and a biomass generator. The models are being used to explore options for hierarchical control, with a focus on optimising the use of the boilers and generator. To achieve this, non-minimal state space model predictive control methods are being adapted for this application. A novelty of the research is the incorporation of weather forecasting and human occupancy data into the control calculations. The research considers the Charles Carter Building as a case study example. This building has a central atrium, surrounded by lecture theatres, offices, meeting rooms and break-out spaces
A thermal-electrical analogy model of a four-floor building with occupancy estimation for heating system control
The well-known electrical analogy for thermal modelling is based on the observation that Fourier's equation for one dimensional heat transfer takes the same form as Ohm's law. This provides a system for creating and resolving complex heat transfer problems using an established set of physically-based equations. In this article, such a model is developed and evaluated for a four-floor modern university building. The model is represented in state space form for optimisation and simulation purposes. The electrical analogy is chosen so that the model can be extended and used for future research into distributed, demand-side control of multiple buildings on the university network, requiring a fast computation time. The estimation of occupancy, representing a significant internal heat source, is also investigated. Here, wifi usage and return CO2 data are combined in novel manner to improve the model response
Computational Fluid Dynamics and Data-Based Mechanistic Modelling of a Forced Ventilation Chamber
The research behind this article ultimately concerns control system robustness and optimisation for the regulation of temperatures in multiple buildings that are linked to a controllable external heating supply network. Lancaster University campus is being used as a case study, for which the building management system provides data. Nonetheless, situations arise when it is difficult or expensive to obtain suitable data for specific rooms or buildings and, in such cases, computational fluid dynamics (CFD) models are utilised to investigate relevant heat transfer phenomena. Such models can be limited by their complexity and they are inappropriate for model-based control design. Hence, the present article investigates a hybrid approach based on both CFD and data-based mechanistic (DBM) models. DBM models are obtained initially from statistical analysis of observational time-series but are only considered credible if they can be interpreted in physically meaningful terms. A laboratory forced ventilation chamber is used to investigate the modelling issues arising and to make recommendations relating to the wider project. The chamber is first discretised into finite volumes and the associated Navier--Stokes equations are solved to determine the physical properties of each zone. The model responses are compared with experimental data and analysed using the DBM approach
Tipifarnib prevents development of hypoxia-induced pulmonary hypertension
Aims. RhoB plays a key role in the pathogenesis of hypoxia - induced pulmonary hypertension. Farne sylated RhoB promotes growth responses in cancer cells and we investigated whether inhibition of protein farnesylation will have a protective effect. Methods and Results. The analysis of l ung tissues from rodent models and pulmonary hypertensive patients showed increased levels of protein farnesylation. Oral farnesyltransferase inhibitor tipifarnib prevented development of hypoxia - induced pulmonary hypertension in mice. Tipifarnib reduced hypoxia - induced vascular cell proliferation, increased endothelium - dependent vasodilatation and reduced vasoconstriction of intrapulmonary arteries without affecting cell viability. Protective effects of tipifarnib were associated with inhibition of Ras and RhoB, actin depolymerisation and increased eNOS expression in vi tro and in vivo . Farnesylated - only RhoB (F - RhoB) increased proliferative responses in cultured pulmonary vascular cells, mimicking the effects of hypoxia, while both geranylgeranylated - only RhoB (GG - RhoB) and tipifarnib had an inhibitory effect. Label - fre e proteomics linked F - RhoB with cell survival, activation of cell cycle and mitochondrial biogenesis. Hypoxia increased and tipifarnib reduced the levels of F - RhoB - regulated proteins in the lung, reinforcing the importance of RhoB as a signalling mediator. Unlike simvastatin, tipifarnib did not increase the expression levels of Rho proteins. Conclusions. Our study demonstrates the importance of protein farnesylation in pulmonary vascular remodeling and provides a rationale for selective targeting of this pa thway in pulmonary hypertension
A novel immunomodulatory function of neutrophils on rhinovirus-Activated monocytes in vitro
© 2016 Published by the BMJ Publishing Group Limited. Background Rhinovirus (RV) infections are the major precipitant of asthma exacerbations. While neutrophilic lung inflammation occurs during such infections, its role remains unclear. Neutrophilic inflammation is associated with increased asthma severity and steroid refractory disease. Neutrophils are vital for controlling infections but also have immunomodulatory functions. Previously, we found that neutrophils respond to viral mimetics but not replication competent RV. We aimed to investigate if neutrophils are activated and/or modulate immune responses of monocytes during RV16 infection. Methods Primary human monocytes and autologous neutrophils were cocultured with or without RV16, in direct contact or separated by transwells. RV16-stimulated monocytes were also exposed to lysed neutrophils, neutrophil membrane components or soluble neutrophil intracellular components. Interleukin 6 (IL-6) and C-X-C motif (CXC)L8 mRNA and proteins were measured by quantitative PCR and ELISA at 24â €..hours. Results RV16 induced IL-6 and CXCL8 in monocytes, but not neutrophils. RV16-induced IL-6 and CXCL8 from monocytes was reduced in the presence of live neutrophils. Transwell separation abolished the inhibitory effects. Lysed neutrophils inhibited RV16-induced IL-6 and CXCL8 from monocytes. Neutrophil intracellular components alone effectively inhibited RV16-induced monocyte-derived IL-6 and CXCL8. Neutrophil intracellular components reduced RV16-induced IL-6 and CXCL8 mRNA in monocytes. Conclusions Cell contact between monocytes and neutrophils is required, and preformed neutrophil mediator(s) are likely to be involved in the suppression of cytokine mRNA and protein production. This study demonstrates a novel regulatory function of neutrophils on RV-Activated monocytes in vitro, challenging the paradigm that neutrophils are predominantly proinflammatory
Distorted Communication, Unequal Representation: Constituents Communicate Less to Representatives Not of Their Race
Communications from constituents strongly shape the representation politicians provide. However, if politicians hear less from some constituents than others, this unequal communication may lead to unequal representation. In this article, I present a field experiment demonstrating that constituents are less likely to communicate to representatives not of their race. The experiment exploited electoral rules in Maryland, where several multimember districts have both black and white representatives. I provided 8,829 residents of such districts an opportunity to communicate to one of their actual representatives, whose race I randomized. Both blacks and whites were markedly less likely to communicate to their representatives not of their race. These results imply that politicians receive racially distorted communication, hearing disproportionately infrequently from constituents unlike them. The fact that most racial minorities have white representatives may thus help explain both minorities' less frequent communication to their representatives and the diminished substantive representation minorities typically receive. © 2013, Midwest Political Science Association
Policy Representation, Social Representation and Class Voting in Britain
Why does the strength of class voting vary over time? Recent research has emphasized factors to do with the structure of political choice at the party level. This article examines different aspects of this choice, and investigates whether voters are more likely to respond to the social cues or policy cues that parties send voters. The results from the British context suggest that the former are more important than the latter. The central implication of this finding is that social representation matters, and that the social background of political representatives influences the ways in which voters relate to political parties
Structure-Activity Relationship Studies of a Novel Class of Transmission Blocking Antimalarials Targeting Male Gametes.
Malaria is still a leading cause of mortality among children in the developing world, and despite the immense progress made in reducing the global burden, further efforts are needed if eradication is to be achieved. In this context, targeting transmission is widely recognized as a necessary intervention toward that goal. After carrying out a screen to discover new transmission-blocking agents, herein we report our medicinal chemistry efforts to study the potential of the most robust hit, DDD01035881, as a male-gamete targeted compound. We reveal key structural features for the activity of this series and identify analogues with greater potency and improved metabolic stability. We believe this study lays the groundwork for further development of this series as a transmission blocking agent
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