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Vigilance: The Essence of Nursing
Meyer, G., Lavin, M.A
Online Journal of Issues in Nursing , 2005,
Abstract: Nursing, perhaps more than any other health care profession, claims caring as fundamental to its practice. Professional vigilance is the essence of caring in nursing. This article uses historical and theoretical bases to define professional vigilance and discuss its components. Two types of nursing diagnoses, central and surveillance, are proposed. Central diagnoses indicate the need for the nurse to plan and implement interventions for the achievement of outcomes. North American Nursing Diagnosis Association (NANDA)-approved diagnoses fall in this category. Surveillance diagnoses are those that recognize patient risks that are anticipated by the nurse, who remains ready to act in the event of occurrence. The profession, as a whole, and language developers, in particular, need to expand standardized nursing diagnosis terminology so that the contribution of nurses' vigilance to patient safety may be effectively communicated and documented.
The NIRS Analysis Package: Noise Reduction and Statistical Inference  [PDF]
Tomer Fekete, Denis Rubin, Joshua M. Carlson, Lilianne R. Mujica-Parodi
PLOS ONE , 2011, DOI: 10.1371/journal.pone.0024322
Abstract: Near infrared spectroscopy (NIRS) is a non-invasive optical imaging technique that can be used to measure cortical hemodynamic responses to specific stimuli or tasks. While analyses of NIRS data are normally adapted from established fMRI techniques, there are nevertheless substantial differences between the two modalities. Here, we investigate the impact of NIRS-specific noise; e.g., systemic (physiological), motion-related artifacts, and serial autocorrelations, upon the validity of statistical inference within the framework of the general linear model. We present a comprehensive framework for noise reduction and statistical inference, which is custom-tailored to the noise characteristics of NIRS. These methods have been implemented in a public domain Matlab toolbox, the NIRS Analysis Package (NAP). Finally, we validate NAP using both simulated and actual data, showing marked improvement in the detection power and reliability of NIRS.
Time perception at different EEG-vigilance levels  [cached]
Minkwitz Juliane,Trenner Maja U,Sander Christian,Olbrich Sebastian
Behavioral and Brain Functions , 2012, DOI: 10.1186/1744-9081-8-50
Abstract: Background Human time perception is influenced by various factors such as attention and drowsiness. Nevertheless, the impact of cerebral vigilance fluctuations on temporal perception has not been sufficiently explored. We assumed that the state of vigilance ascertained by electroencephalography (EEG) during the perception of a given auditory rhythm would influence its reproduction. Thus, we hypothesised that the re-tapping interval length and the accuracy of reproduction performance would vary depending on the state of vigilance determined by EEG. Methods 12 female and 9 male subjects ranging from 21 to 38 years (M = 25.52, SD = 3.75) participated in a test paradigm comprising a) a resting EEG for the determination of vigilance while an auditory rhythm was presented, b) a short activity of the proband to be sure of sufficient alertness, and c) a tapping task to reproduce the presented rhythm. Vigilance states of three consecutive 1-sec-EEG-segments of the resting EEG before the reproduction phase were classified using the Vigilance Algorithm Leipzig (VIGALL). Results and discussion Reproduction accuracy was more precise after high EEG-vigilance stages. Thus, the subjects’ mean deviation from the given rhythm was lower (t(17) = 2.733, p < 0.05) after high vigilance stage A (MW = 0.046, SD = 0.049) than after low vigilance stage B (MW = 0.065, SD = 0.067). The re-tapping-length was significantly shorter (t(17) = 2.190, p < 0.05) for reproduction phases following high EEG-vigilance stage A compared to the lower EEG-vigilance stage B. Conclusion These findings support the hypothesis of a varying time perception and of speed alterations of the internal clock after different states of EEG-vigilance, which were automatically classified by VIGALL. Thus, alterations of cognitive processing may be assessable by specific EEG-patterns.
Morning Anaerobic Performance Is Not Altered by Vigilance Impairment  [PDF]
Romain Lericollais, Antoine Gauthier, Nicolas Bessot, Amira Zouabi, Damien Davenne
PLOS ONE , 2013, DOI: 10.1371/journal.pone.0058638
Abstract: The aim of this study was to determine the role played by vigilance on the anaerobic performance recorded during a Wingate test performed at the bathyphase (nadir) of the circadian rhythmicity. Twenty active male participants performed a 60-s Wingate test at 6 a.m. during 3 test sessions in counter-balanced order the day after either (i) a normal reference night, (ii) a total sleep deprivation night, or (iii) a total sleep deprivation night associated with an extended simulated driving task from 9 p.m. to 5 a.m. During this task, the number of inappropriate line crossings (ILCs) was used to control and quantify the effective decrease in the level of vigilance. The main findings show that (i) vigilance of each participant was significantly altered (i.e., a drastic and progressive increase in ILCs is shown during the 7.5 hours of driving) by the sleep deprivation night associated with an extended driving task; (ii) the subjective evaluation of vigilance performed by self-rated scale revealed an increased impairment of the vigilance level between the normal reference night, the total sleep deprivation night and the total sleep deprivation night associated with an extended driving task; and (iii) the morning following this last condition, during the Wingate test, the recorded cycling biomechanical parameters (peak power, mean power and fatigue index values, power decrease, and cycling kinetic and kinematic patterns) were not significantly different from the two other conditions. Consequently, these results show that anaerobic performances recorded during a Wingate test performed at the bathyphase of the circadian rhythmicity are not altered by a drastic impairment in vigilance. These findings seem to indicate that vigilance is probably not a factor that contributes to circadian variations in anaerobic performance.
Optimal Vigilance Level and Hiring Illegal Immigrants  [PDF]
Munirul H. Nabin, Pasquale M. Sgro
Theoretical Economics Letters (TEL) , 2017, DOI: 10.4236/tel.2017.71001
Abstract: This paper assumes a Ricardian Economy and analyzes migration of illegal unskilled workers in a model of Cournot Duopoly where firms are producing homogenous and non-traded goods, and hiring illegal immigrants. The focus is on the behaviours of firms and the implications for the output, prices and employment of domestic workers in that industry. A two-stage simultaneous move game is set up: In Stage 1, for a given technology and vigilance level, each individual firm will decide whether to hire illegal immigrants. In Stage 2, each firm will choose the Cournot output level. Using this structure, we provide additional insights as to why firms hire illegal workers and what motivates these firms in their hiring practices. Furthermore the presence of illegal immigrants may create more employment for domestic workers and a social planner can be strategic in choosing optimal level of vigilance as we have shown that multiple solutions for optimal vigilance are possible and also Pareto ranked.
Relationship between prospective memory and vigilance: Evidence from ERP
Ya Wang,XueBing Li,Jia Huang,XiaoYan Cao,JiFang Cui,Qing Zhao,YuNa Wang,David H. K. Shum,Raymond C. K. Chan
Chinese Science Bulletin , 2012, DOI: 10.1007/s11434-012-5306-9
Abstract: Event-related potentials (ERPs) were used in this study to investigate the neural correlates of prospective memory (PM) and vigilance. Twenty college or graduate students participated in this study. They were administered a PM and a vigilance task and physiological data were collected at the same time. Behavioral results showed that the RT associated with PM cues was longer than those associated with vigilance targets. ERP results showed that PM cues and vigilance targets did not show significant difference in the N2 but PM cues evoked greater N300 than vigilance targets, and vigilance targets evoked greater parietal positivity/P3 than PM cues, suggesting vigilance and PM have similar but also distinctive neural basis.
Speeded Near Infrared Spectroscopy (NIRS) Response Detection  [PDF]
Xu Cui,Signe Bray,Allan L. Reiss
PLOS ONE , 2012, DOI: 10.1371/journal.pone.0015474
Abstract: The hemodynamic response measured by Near Infrared Spectroscopy (NIRS) is temporally delayed from the onset of the underlying neural activity. As a consequence, NIRS based brain-computer-interfaces (BCIs) and neurofeedback learning systems, may have a latency of several seconds in responding to a change in participants' behavioral or mental states, severely limiting the practical use of such systems. To explore the possibility of reducing this delay, we used a multivariate pattern classification technique (linear support vector machine, SVM) to decode the true behavioral state from the measured neural signal and systematically evaluated the performance of different feature spaces (signal history, history gradient, oxygenated or deoxygenated hemoglobin signal and spatial pattern). We found that the latency to decode a change in behavioral state can be reduced by 50% (from 4.8 s to 2.4 s), which will enhance the feasibility of NIRS for real-time applications.
Maturation of the cytochrome cd1 nitrite reductase NirS from Pseudomonas aeruginosa requires transient interactions between the three proteins NirS, NirN and NirF  [cached]
Tristan Nicke,Tobias Schnitzer,Karin Münch,Julia Adamczack
Bioscience Reports , 2013, DOI: 10.1042/bsr20130043
Abstract: The periplasmic cytochrome cd1 nitrite reductase NirS occurring in denitrifying bacteria such as the human pathogen Pseudomonas aeruginosa contains the essential tetrapyrrole cofactors haem c and haem d1. Whereas the haem c is incorporated into NirS by the cytochrome c maturation system I, nothing is known about the insertion of the haem d1 into NirS. Here, we show by co-immunoprecipitation that NirS interacts with the potential haem d1 insertion protein NirN in vivo. This NirS–NirN interaction is dependent on the presence of the putative haem d1 biosynthesis enzyme NirF. Further, we show by affinity co-purification that NirS also directly interacts with NirF. Additionally, NirF is shown to be a membrane anchored lipoprotein in P. aeruginosa. Finally, the analysis by UV–visible absorption spectroscopy of the periplasmic protein fractions prepared from the P. aeruginosa WT (wild-type) and a P. aeruginosa ΔnirN mutant shows that the cofactor content of NirS is altered in the absence of NirN. Based on our results, we propose a potential model for the maturation of NirS in which the three proteins NirS, NirN and NirF form a transient, membrane-associated complex in order to achieve the last step of haem d1 biosynthesis and insertion of the cofactor into NirS.
Quantification of MBM adulteration in compound fertilizers and composts by NIRS  [PDF]
Han L.,Liu X.,Zhu R.,Yang Z.
Biotechnologie, Agronomie, Société et Environnement , 2009,
Abstract: The objective of this study was to demonstrate the feasibility of using near infrared reflectance spectroscopy (NIRS) to determine MBM content in compound fertilizers and composts. One hundred fourty adulterated compound fertilizer samples were prepared in the laboratory by mixing 4 types of compound fertilizers with 3 types of MBM randomly at different levels of 0.1%-10.0% (w/w). One hundred twenty adulterated compost samples were obtained by mixing 41 compost samples with 28 MBM at different levels of 3.0%-24.0% (w/w). NIRS calibration models were developed using the partial least squares (PLS) regression method. Results showed that the coefficients of determination for calibration (R2) and validation (r2) were 0.996 and 0.622, 0.988 and 0.722 for adulterated compound fertilizers and composts respectively. The ratios of prediction to deviation (RPD) were 8.84 and 1.87 for them respectively. These results indicated that NIRS could be used to quantify the adulteration of banned MBM in compound fertilizers with high prediction accuracy, and be insufficient to determine the content of MBM in composts due to low prediction accuracy.
Simultaneous in-situ NIRS of liver and bowel during septic shock  [PDF]
R. E. Gagnon,E. Hahum,E. Skarsgard,A. J. Macnab
Spectroscopy: An International Journal , 2006, DOI: 10.1155/2006/285157
Abstract: We wished to use near infrared spectroscopy (NIRS) to evaluate changes in blood perfusion in the liver and small bowel. However, conventional clinical NIRS probes use adhesive light shielding appliqués that fail in direct contact with the wetness and softness of the liver and small bowel surfaces. We describe our development and testing of customized NIRS probe holders.
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