Analysis of ITU-R Performance and Characterization of Ku Band Satellite Downlink Signals during Rainy Season over Chennai Region of India

In this paper, we present the analysis of Ku band Satellite signal reception during rainy season over Chennai region, India (Latitude: 12° 56' 60 N, Longitude: 80° 7' 60 E). We also examine the effectiveness of International Telecommunication Union – Radio communication (ITU-R) model in predicting the rainfall induced attenuation in Ku band, over this region. An improved Simulink model for Digital Video Broadcast – Satellite (DVB-S2) downlink channel incorporating rain attenuation and Cross Polarization Discrimination (XPD) effects is developed to study the rain attenuation effects, by introducing the experimental data in the ITU-R model pertaining to that region. Based on the improved model, a Monte Carlo simulation of the DVB–S2 signal link is carried out and the performance is analyzed by received constellation and Bit Error Rate (BER) parameters

Neuronal and Cognitive Plasticity: A Neurocognitive Framework for Ameliorating Cognitive Aging

What is the neurocognitive basis for the considerable individual differences observed in functioning of the adult mind and brain late in life? We review the evidence that in healthy old age the brain remains capable of both neuronal and cognitive plasticity, including in response to environmental and experiential factors. Neuronal plasticity (e.g., neurogenesis, synaptogenesis, cortical re-organization) refers to neuron-level changes that can be stimulated by experience. Cognitive plasticity (e.g., increased dependence on executive function) refers to adaptive changes in patterns of cognition related to brain activity. We hypothesize that successful cognitive aging requires interactions between these two forms of plasticity. Mechanisms of neural plasticity underpin cognitive plasticity and in turn, neural plasticity is stimulated by cognitive plasticity. We examine support for this hypothesis by considering evidence that neural plasticity is stimulated by learning and novelty and enhanced by both dietary manipulations (low-fat, dietary restriction) and aerobic exercise. We also examine evidence that cognitive plasticity is affected by education and training. This is a testable hypothesis which could be assessed in humans in randomized trials comparing separate and combined effects of cognitive training, exercise, and diet on measures of cognitive and brain integrity. Greater understanding of the factors influencing the course of cognitive aging and of the mechanisms underlying those factors could provide information on which people could base choices that improve their ability to age successfully

PRM51 From Clinical Trial to Real-World Evidence: A Systematic Approach to Identifying Data Sources for Observational Research

Edifici industrial de dos cossos de planta baixa i tres plantes pis acabades amb mansarda. Destaca el nombre i dimensions de les obertures que permeten una gran entrada de llum a l'interior i l'amplitud de les plantes diàfanes.Digitalitzat per Tecnodo

Population Pharmacokinetics of Intraventricular Vancomycin in Neonatal Ventriculitis, A Preterm Pilot Study

AIM: Intraventricular vancomycin is an effective treatment for neonatal ventriculitis, as the cerebrospinal fluid (CSF) vancomycin levels reach adequate concentrations to achieve microbiological cure. There is no robust data on intraventricular vancomycin pharmacokinetics in the preterm population. This pilot population pharmacokinetic modelling study examines the pharmacokinetic behaviour of intraventricular vancomycin in the preterm population of < 28 weeks gestation, to inform the feasibility of future prospective studies. METHODS: The study comprised 8 preterm infants with neonatal ventriculitis (median gestation age 25.3 weeks; range 23.9 - 27.7). Population pharmacokinetics (non-linear mixed effects modelling) were described with one- and two-compartment models to fit plasma concentrations of vancomycin. A CSF compartment was added to the plasma modelling and mass transfer examined. Three covariates (serum creatinine, ventricular index (VI) and CSF protein) were tested on the final model. Area under the curve (AUC) and average CSF concentration (C average) predictions were generated from the final model and compared with time to microbiological cure. RESULTS: A one-compartment model provided the best fit to the data. There was no appreciable transfer between plasma and CSF. None of the covariates provided a significant reduction in the objective function value (OFV). Generally, time to sterilisation with higher CSF AUC (0-24) and C average tends to be shorter, however this should be interpreted with caution as data is erratic. CONCLUSION: This pilot population pharmacokinetic analysis provides important information to warrant changes in the management of intraventricular vancomycin treatment in the preterm population, such as the current use of VI as a dosing parameter. Further study with a larger data pool is necessary to investigate the influence of VI on CSF vancomycin and ascertain dosing strategies

More than a feeling? Toward a theory of customer delight

PurposeResponding to an increasing call for a more comprehensive conceptualization of customer delight, the purpose of this paper is to expand the theory of customer delight and to examine the implications of such an expanded view for service theory and practice.Design/methodology/approachThis paper presents the results of three qualitative studies. The first study explores customer delight through self-reported consumption experiences in customer-selected contexts, followed by one-on-one in-depth interviews. The second involves focus groups and the third examines self-reported incidents of delightful customer experiences.FindingsThis research finds that customer delight goes beyond extreme satisfaction and joy and surprise to include six properties that—individually or in combination—characterize customer delight. An expanded conceptualization of how customer delight can be defined is proposed in which customer delight is associated with various combinations of six properties – the customer experiencing positive emotions, interacting with others, successful problem-solving, engaging customer’s senses, timing of the events and sense of control that characterizes the customer's encounter.Research limitations/implicationsIt is clear from the findings of this research that there is no single property that is associated with delight. Through the facilitation of multiple properties, managers have the potential to create a multitude of routes to delight. It is recommended that future research (1) identify and explicate these alternative routes for engendering delight using the six properties identified, and (2) develop a general typology based on service context and characteristics, customer segment, etc. that further stimulates scholarship on delight, and offers more industry-specific insights for managers.Practical implicationsInsights from this investigation will encourage managers and service designers to think more broadly and creatively about delight. Doing so will open up new opportunities for achieving customer delight, beyond merely focusing on extreme satisfaction or surprise and joy strategies currently dominating discussions of customer delight.Originality/valueThis paper makes several contributions to the service literature. First, it extends current conceptualizations of customer delight and offers an expanded definition. Next, it demonstrates how this new understanding extends the existing literature on delight. Finally, it proposes an agenda for future delight research and discusses managerial implications, opening up new opportunities for firms to design delightful customer experiences.</jats:sec

Attention and automation: New perspectives on mental underload and performance

There is considerable evidence in the ergonomics literature that automation can significantly reduce operator mental workload. Furthermore, reducing mental workload is not necessarily a good thing, particularly in cases where the level is already manageable. This raises the issue of mental underload, which can be at least as detrimental to performance as overload. However, although it is widely recognized that mental underload is detrimental to performance, there are very few attempts to explain why this may be the case. It is argued in this paper that, until the need for a human operator is completely eliminated, automation has psychological implications relevant in both theoretical and applied domains. The present paper reviews theories of attention, as well as the literature on mental workload and automation, to synthesize a new explanation for the effects of mental underload on performance. Malleable attentional resources theory proposes that attentional capacity shrinks to accommodate reductions in mental workload, and that this shrinkage is responsible for the underload effect. The theory is discussed with respect to the applied implications for ergonomics research

Neurogenetic Effects on Cognition in Aging Brains: A Window of Opportunity for Intervention?

Knowledge of genetic influences on cognitive aging can constrain and guide interventions aimed at limiting age-related cognitive decline in older adults. Progress in understanding the neural basis of cognitive aging also requires a better understanding of the neurogenetics of cognition. This selective review article describes studies aimed at deriving specific neurogenetic information from three parallel and interrelated phenotype-based approaches: psychometric constructs, cognitive neuroscience-based processing measures, and brain imaging morphometric data. Developments in newer genetic analysis tools, including genome wide association, are also described. In particular, we focus on models for establishing genotype–phenotype associations within an explanatory framework linking molecular, brain, and cognitive levels of analysis. Such multiple-phenotype approaches indicate that individual variation in genes central to maintaining synaptic integrity, neurotransmitter function, and synaptic plasticity are important in affecting age-related changes in brain structure and cognition. Investigating phenotypes at multiple levels is recommended as a means to advance understanding of the neural impact of genetic variants relevant to cognitive aging. Further knowledge regarding the mechanisms of interaction between genetic and preventative procedures will in turn help in understanding the ameliorative effect of various experiential and lifestyle factors on age-related cognitive decline

Development of Electromyography Signal Signature for Forearm Muscle

AbstractElectromyography (EMG) measures muscle response or electrical activity in response to a nerve's stimulation of the muscle. EMG is generally acquired through surface and needle or wire electrodes. The needle or wire electrodes are usually used by clinicians in a clinical setting. This paper concentrates on surface electromyography (sEMG) signal that is acquired in a research laboratory since sEMG is increasingly being recognized as the gold standard for the analysis of muscle activation. The sEMG can utilized for establishing signal signature for forearm muscles that becomes an important input in development of rehabilitative devices. This paper discusses the establishment of sEMG signal signature of female and male subjects for forearm muscles such as extensor carpi radialis, flexor carpi radialis, palmaris longus and pronator teres based on movements such as wrist extension and flexion, hand open and close, and forearm supination and pronation. This was achieved through the use of Butterworth Bessel, Elliptic and Chebyshev filters. The sEMG signal signature could be useful in the development of rehabilitation device of upper extremities

REFERQUAL: A pilot study of a new service quality assessment instrument in the GP Exercise Referral scheme setting

Background The development of an instrument accurately assessing service quality in the GP Exercise Referral Scheme (ERS) industry could potentially inform scheme organisers of the factors that affect adherence rates leading to the implementation of strategic interventions aimed at reducing client drop-out. Methods A modified version of the SERVQUAL instrument was designed for use in the ERS setting and subsequently piloted amongst 27 ERS clients. Results Test re-test correlations were calculated via Pearson's 'r' or Spearman's 'rho', depending on whether the variables were Normally Distributed, to show a significant (mean r = 0.957, SD = 0.02, p < 0.05; mean rho = 0.934, SD = 0.03, p < 0.05) relationship between all items within the questionnaire. In addition, satisfactory internal consistency was demonstrated via Cronbach's 'α'. Furthermore, clients responded favourably towards the usability, wording and applicability of the instrument's items. Conclusion REFERQUAL is considered to represent promise as a suitable tool for future evaluation of service quality within the ERS community. Future research should further assess the validity and reliability of this instrument through the use of a confirmatory factor analysis to scrutinise the proposed dimensional structure