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61.
Shamanth Nagaraju Sreejith V Lucy J. Gudino Bhushan V. Kadam Ramesha C. K. Joseph Rodrigues 《International Journal of Communication Systems》2020,33(4)
In common practice, sensor nodes are randomly deployed in wireless sensor network (WSN); hence, location information of sensor node is crucial in WSN applications. Localization of sensor nodes performed using a fast area exploration mechanism facilitates precise location‐based sensing and communication. In the proposed localization scheme, the mobile anchor (MA) nodes integrated with localization and directional antenna modules are employed to assist in localizing the static nodes. The use of directional antennas evades trilateration or multilateration techniques for localizing static nodes thereby resulting in lower communication and computational overhead. To facilitate faster area coverage, in this paper, we propose a hybrid of max‐gain and cost‐utility–based frontier (HMF) area exploration method for MA node's mobility. The simulations for the proposed HMF area exploration–based localization scheme are carried out in the Cooja simulator. The paper also proposes additional enhancements to the Cooja simulator to provide directional and sectored antenna support. This additional support allows the user with the flexibility to feed radiation pattern of any antenna obtained either from simulated data of the antenna design simulator, ie, high frequency structure simulator (HFSS) or measured data of the vector network analyzer (VNA). The simulation results show that the proposed localization scheme exhibits minimal delay, energy consumption, and communication overhead compared with other area exploration–based localization schemes. The proof of concept for the proposed localization scheme is implemented using Berkeley motes and customized MA nodes mounted with indigenously designed radio frequency (RF) switch feed network and sectored antenna. 相似文献
62.
Lucy Gloag Milad Mehdipour Dongfei Chen Richard D. Tilley J. Justin Gooding 《Advanced materials (Deerfield Beach, Fla.)》2019,31(48)
Magnetic nanoparticles (MNPs) are of high significance in sensing as they provide viable solutions to the enduring challenges related to lower detection limits and nonspecific effects. The rapid expansion in the applications of MNPs creates a need to overview the current state of the field of MNPs for sensing applications. In this review, the trends and concepts in the literature are critically appraised in terms of the opportunities and limitations of MNPs used for the most advanced sensing applications. The latest progress in MNP sensor technologies is overviewed with a focus on MNP structures and properties, as well as the strategies of incorporating these MNPs into devices. By looking at recent synthetic advancements, and the key challenges that face nanoparticle‐based sensors, this review aims to outline how to design, synthesize, and use MNPs to make the most effective and sensitive sensors. 相似文献
63.
Sridharshi Chintha Hewawitharana Frances Elizabeth Thompson Catherine M. Loria Warren Strauss Jyothi Nagaraja Lorrene Ritchie Karen Lucy Webb 《Nutrition journal》2018,17(1):111
Background
A dietary screener questionnaire (DSQ) was used to assess dietary outcomes among children in the Healthy Communities Study (HCS), a study of the relationships between programs and policies to prevent child obesity and child diet, physical activity and weight outcomes.Methods
To compare dietary intake estimates derived from the DSQ against those from the Automated Self-Administered 24-Hour Recalls for Children (ASA24-Kids) among children, a measurement error model, using structural equation modelling, was utilized to estimate slopes, deattenuated correlation coefficients, and attenuation factors by age and sex, ethnicity, and BMI status.Participants/setting
A randomly selected sub-sample of HCS participants aged 4–15 years in 130 communities throughout the U.S. who completed the DSQ and up to two ASA24-Kids recalls (n?=?656;13% of HCS participants).Results
For most nutrient/foods examined, the DSQ yielded larger mean intake estimates than the ASA24-Kids, and agreement between the two measures varied by food/nutrient, age and sex, ethnicity, and BMI category. Deattenuated correlation coefficients of 0.4 or greater were observed for added sugars from SSBs (0.54), fruits and vegetables (0.40), and dairy foods (0.50). Lower deattenuated correlation coefficients were seen for total added sugars (0.37), whole grains (0.34), and fiber (0.34). Attenuation factors were most severe for total added sugars intake among overweight children, and for several other dietary outcomes among children aged 9–11 years.Conclusions
The DSQ was found to be a tool with acceptable agreement with the ASA24-Kids for measuring multiple dietary outcomes of interest in the HCS, although there may be potential due to measurement error to underestimate results (bias towards the null). In future studies, measurement error modelling and regression calibration may be possible solutions to correct for bias due to measurement error in most food/nutrient intake estimates from the DSQ when used among children.64.
ABSTRACTThis paper examines the issue of assessing the value of social design research. It locates the emergence of social design practice and research against a background in which public and social organisations are increasingly bureaucratised as a result of New Public Management and shifts to New Public Governance. Within universities, too, organisational processes and structures require research to demonstrate impact within an audit culture. Through the study presented in this paper, we claim that the bureaucracies found in contemporary academia are ill-equipped to adequately assess generative, impactful, and multi-sited research in which value is co-produced with diverse participants. This presents challenges when attempting to understand the value of social design research. Building on social research and studies of innovation policy, sustainable human-computer interaction and evaluation, we define social design research as inventive, contingent, and political. To address the issue of its evaluation, we propose two-stage social design research. In the first stage, research issues, questions, methods, data, and ‘proto-publics’ are assembled, which reveal the conflicting framings and ways that value is assessed. These are re-assembled in a second stage during which the research is stabilised. The findings have implications for research managers, academics and their partners, and university administrators. 相似文献
65.
Barnard Lucy; Stevens Tara; Siwatu Kamau Oginga; Lan William 《Canadian Metallurgical Quarterly》2008,1(3):169
A survey of a sample of faculty (N = 201) at a large, public university located in the Southwest was conducted to investigate whether differences in faculty attitudes toward diversity positively mediate faculty attitudes toward persons with disabilities. In addition, the current study examined whether differences in faculty attitudes toward diversity may be viewed as positively mediating the relationship between instructor characteristics and their attitudes toward persons with disabilities. This study concludes that faculty members may not be viewing disability as part of the greater construct of diversity with empirical evidence. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
66.
Where did that car come from?: Crossing the road when the traffic comes from an unfamiliar direction
Using a virtual road crossing environment, the reported research investigated the road crossing behavior of 12 male pedestrians in familiar and unfamiliar environments. Environment familiarity was manipulated using traffic direction. Seven of the participants were from a country where traffic flows from right to left and five were from countries were traffic flows from left to right. Each participant was asked to cross the road when traffic was coming from both the familiar and the unfamiliar direction for them. Results showed that pedestrians had lower safety ration, or a lower margin of error, in crossing the road when traffic was flowing in an unfamiliar direction, suggesting that pedestrians might be at greater risk of accident in such environments. Implications of these findings are discussed. 相似文献
67.
Lucy Bullivant 《Architectural Design》2005,75(1):38-45
Lucy Bullivant looks at the shape of the new office to come. With the onset of increasingly sophisticated communications devices, how is the organisation of space in our immediate working environments going to change? Will the lines between furniture and dynamic electronic devices simply blur? Will the structure of commercial office buildings themselves be required to become increasingly reflexive to meet environmental demands in the face of dwindling energy reserves? Or is the mobile nature of electronic communications actually in danger of rendering the permanent office as we know it extinct? Copyright © 2005 John Wiley & Sons, Ltd. 相似文献
68.
境外建筑师事务所如何适应当前国内的建筑潮流并在其中有所作为?除了在方案竞赛中能展现具有“视觉震撼性”的透视效果图外,还要具备一套行之有效的设计管理系统。主要包括三方面内容:1.团队精神,2.各专业之间的协调,3.阶段性设计质量的保证。文章将就这三个内容展开讨论。 相似文献
69.
Overexpression of Tropomyosin Isoform Tpm3.1 Does Not Alter Synaptic Function in Hippocampal Neurons
Chanchanok Chaichim Tamara Tomanic Holly Stefen Esmeralda Paric Lucy Gamaroff Alexandra K. Suchowerska Peter W. Gunning Yazi D. Ke Thomas Fath John Power 《International journal of molecular sciences》2021,22(17)
Tropomyosin (Tpm) has been regarded as the master regulator of actin dynamics. Tpms regulate the binding of the various proteins involved in restructuring actin. The actin cytoskeleton is the predominant cytoskeletal structure in dendritic spines. Its regulation is critical for spine formation and long-term activity-dependent changes in synaptic strength. The Tpm isoform Tpm3.1 is enriched in dendritic spines, but its role in regulating the synapse structure and function is not known. To determine the role of Tpm3.1, we studied the synapse structure and function of cultured hippocampal neurons from transgenic mice overexpressing Tpm3.1. We recorded hippocampal field excitatory postsynaptic potentials (fEPSPs) from brain slices to examine if Tpm3.1 overexpression alters long-term synaptic plasticity. Tpm3.1-overexpressing cultured neurons did not show a significantly altered dendritic spine morphology or synaptic activity. Similarly, we did not observe altered synaptic transmission or plasticity in brain slices. Furthermore, expression of Tpm3.1 at the postsynaptic compartment does not increase the local F-actin levels. The results suggest that although Tpm3.1 localises to dendritic spines in cultured hippocampal neurons, it does not have any apparent impact on dendritic spine morphology or function. This is contrary to the functional role of Tpm3.1 previously observed at the tip of growing neurites, where it increases the F-actin levels and impacts growth cone dynamics. 相似文献
70.
Luteinization of porcine preovulatory follicles leads to systematic changes in follicular gene expression 总被引:1,自引:0,他引:1
Agca C Ries JE Kolath SJ Kim JH Forrester LJ Antoniou E Whitworth KM Mathialagan N Springer GK Prather RS Lucy MC 《Reproduction (Cambridge, England)》2006,132(1):133-145
The LH surge initiates the luteinization of preovulatory follicles and causes hormonal and structural changes that ultimately lead to ovulation and the formation of corpora lutea. The objective of the study was to examine gene expression in ovarian follicles (n = 11) collected from pigs (Sus scrofa domestica) approaching estrus (estrogenic preovulatory follicle; n = 6 follicles from two sows) and in ovarian follicles collected from pigs on the second day of estrus (preovulatory follicles that were luteinized but had not ovulated; n = 5 follicles from two sows). The follicular status within each follicle was confirmed by follicular fluid analyses of estradiol and progesterone ratios. Microarrays were made from expressed sequence tags that were isolated from cDNA libraries of porcine ovary. Gene expression was measured by hybridization of fluorescently labeled cDNA (preovulatory estrogenic or -luteinized) to the microarray. Microarray analyses detected 107 and 43 genes whose expression was decreased or increased (respectively) during the transition from preovulatory estrogenic to -luteinized (P<0.01). Cells within preovulatory estrogenic follicles had a gene-expression profile of proliferative and metabolically active cells that were responding to oxidative stress. Cells within preovulatory luteinized follicles had a gene-expression profile of nonproliferative and migratory cells with angiogenic properties. Approximately, 40% of the discovered genes had unknown function. 相似文献