Smaller Coefficient Of Variation Research Articles

Inter-device concordance of Veggie Meter-A reflection spectroscopy to measure skin carotenoids.

The Veggie Meter® (VM) is a refraction spectrometer that detects skin carotenoids. We tested the variability of the two modes (single-scan and averaging modes) of four VMs of three different versions (VM-1, 2, 3, 4) with 92 healthy volunteers. Both the modes exhibited a high intra-class correlation coefficient (ICC); however, the averaging mode had a significantly lower coefficient of variance than the single-scan mode. The Bland-Altman analysis showed a systematic error between VM-1 and other three VMs. The actual errors between the VM-1 and the other three VMs in the averaging mode were 7.4%, 10.4%, and 11.8% of the median of VM scores, but the errors could be reduced to 2.8%, 6.3%, and 7.0% by compensating VM scores using the regression equations. Averaging mode had higher accuracy than single-scan mode. The reliability of the VMs was validated by the small coefficient of variation and high ICC. The error was improved using linear regression compensation.

Experimental Research on the Cold-Forming Effect of Cold-Formed Thick-Walled Steel

To study the cold-forming effect on the yield strength distribution of cold-formed thick-walled steel, material tensile tests and axial compression tests were conducted on steel-lipped channels. To undertake the material tensile tests, five types of cold-formed lipped channel sections with varied thicknesses and nominal yield strengths were selected. The material test samples were taken from the web, flange, curled edge, and corner of the lipped channel sections, respectively. Next, a corresponding distribution model for the yield strength of cold-formed thick-walled lipped channel sections was developed. Following this, axial compression tests of five short columns with the same section as the coupon tests were conducted to further investigate the cold-forming effect. Finally, the results from the short column tests, the results based on the proposed yield strength distribution model, and the results calculated for related codes in various countries were compared. These revealed that the yield strength distribution, bearing capacity, and ductility were considerably influenced by the cold-forming effect and mainly depended on the width-to-thickness ratio (h/t) of the plate involved. When h/t was less than 34, the curve slowly decreased after reaching the peak load and had good ductility. Conversely, when h/t was greater than 71, local buckling had an obvious influence on the bearing capacity of the specimen, and the column ductility was poor. Overall, the results based on the Chinese code GB 50018-2002 were closest to the experimental values with the smallest variation coefficient, and therefore this code has the best applicability.

Similarity assessment of using helium to predict smoke movement through buildings with double skin façades during building integrated photovoltaics fires

In comparison to the building attached photovoltaics (BAPVs), Building Integrated Photovoltaics (BIPVs) drive more changes in building envelope. Therefore, tackling the fire safety of building integrated photovoltaic is more complicated due to these changes and the interaction between photovoltaic panels and the building. The photovoltaic fire hazards, including smoke generation of solar glazing, closely affect the fire safety of the building and occupants. This effect is further exemplified in the case of solar double skin façade systems where the stack effect influences smoke spread from ignited integrated photovoltaic panels via the vertical space of plenum in double skin façade. In scientific research field, the sub-scale model or laboratory-scale experiments is often applied to study the building fire smoke spread, which is much less costly, time and effort consuming, compared with full-scale test. However, the major concern of the sub-scale fire tests is providing the efficient but safe ignition source. There are methods such as cold smoke and hot gas (hot smoke test), each of which has their specific limitations on the cost and safety. This paper proposes an alternative method of helium smoke to substitute the real fire test for simulating a real integrated solar façade fire. First the fire dynamic simulator model with helium source is validated by experimental helium test along with particle image velocimetry in terms of helium concentration and flow velocity. The differences between the experiments and simulations are in the acceptable range (23 and 24%). Helium smoke result similarity is then compared to small scale real fire which showed close agreement according to the small coefficient of variation (between 1.6 and 11%).

Imprecision remains to be improved in the measurement of serum cystatin C with heterogeneous systems.

Except for the large bias of some measurement systems for serum cystatin C (CysC) measurements, unacceptable imprecision has been observed for the heterogenous system. This study analyzed the external quality assessment (EQA) results in 2018-2021 to provide an insight into the imprecision of CysC assays. Five EQA samples were sent to participating laboratories every year. Participants were divided into reagent/calibrator-based peer groups, for which the robust mean of each sample and robust coefficient of variation (CV) were calculated by Algorithm A from ISO 13528. Peers with more than 12 participants per year were selected for further analysis. The limit of CV was determined to be 4.85% based on clinical application requirements. The concentration-related effect on CVs was investigated using logarithmic curve fitting; the difference in medians and robust CVs between instrument-based subgroups was also evaluated. The total number of participating laboratories increased from 845 to 1,695 in four years and heterogeneous systems remained the mainstream (≥85%). Of 18 peers with≥12 participants, those using homogeneous systems showed relatively steady and small CVs over four years, with the mean four-year CVs ranging from 3.21 to 3.68%. Some peers using heterogenous systems showed reduced CVs over four years, while 7/15 still had unacceptable CVs in 2021 (5.01-8.34%). Six peers showed larger CVs at the low or high concentrations, and some instrument-based subgroups presented greater imprecision than others. More efforts should be made to improve theimprecision of heterogeneous systems for CysC measurement.

Effect of corroded reinforcement on capacity of square reinforced concrete columns confined with FRP sheets under eccentric loads

Steel corrosion is one of the primary causes which significantly degrade the load-carrying capacity and FRP (fibre reinforced polymer) strengthening efficiency of FRP-strengthened reinforced concrete columns under eccentric loading. However, this issue has not been studied comprehensively and systematically in the literature. Particularly, there has been no study on the strengthening efficiency of basalt FRP (BFRP) which is becoming popular due to its excellent performance and affordable price. This study experimentally investigates the effect of corrosion level of reinforcement by mass (0%, 15% and 30%), relative eccentricity (e/h = 0.125 and 0.375), type of FRP (CFRP and BFRP) and FRP thickness (1 or 3 layers) on the load-carrying capacity and deformation of corroded-reinforcement reinforced concrete (RC) columns. The experimental results showed that steel corrosion reduced the load-carrying capacity of the unstrengthened RC columns up to 23% and this degradation increased with the corrosion level. Both CFRP and BFRP have proven excellent strengthening efficiency since the capacity of the FRP-strengthened corroded-reinforcement RC columns increased up to 47%. Particularly, the strengthening efficiency of BFRP sheets was slightly lower than that of CFRP sheets (<7%). On the other hand, the increase of the relative eccentricity from e/h = 0.125 to e/h = 0.375 reduced the strengthening efficiency of FRP. In addition, a semi-empirical model was proposed to predict the capacity of corroded-reinforcement RC columns strengthened with FRP under eccentric loading. The predictions match well with the experimental results with a small coefficient of variation.

Comparative Analysis of the Symbiotic Microbiota in the Chinese Mitten Crab (Eriocheir sinensis): Microbial Structure, Co-Occurrence Patterns, and Predictive Functions

Symbiotic microorganisms in the digestive and circulatory systems are found in various crustaceans, and their essential roles in crustacean health, nutrition, and disease have attracted considerable interest. Although the intestinal microbiota of the Chinese mitten crab (Eriocheir sinensis) has been extensively studied, information on the symbiotic microbiota at various sites of this aquatic economic species, particularly the hepatopancreas and hemolymph, is lacking. This study aimed to comprehensively characterize the hemolymph, hepatopancreas, and intestinal microbiota of Chinese mitten crab through the high-throughput sequencing of the 16S rRNA gene. Results showed no significant difference in microbial diversity between the hemolymph and hepatopancreas (Welch t-test; p > 0.05), but their microbial diversity was significantly higher than that in the intestine (p < 0.05). Distinct differences were found in the structure, composition, and predicted function of the symbiotic microbiota at these sites. At the phylum level, the hemolymph and hepatopancreas microbiota were dominated by Proteobacteria, Firmicutes, and Acidobacteriota, followed by Bacteroidota and Actinobacteriota, whereas the gut microbiota was mainly composed of Firmicutes, Proteobacteria, and Bacteroidota. At the genus level, Candidatus Hepatoplasma, Shewanella, and Aeromonas were dominant in the hepatopancreas; Candidatus Bacilloplasma, Roseimarinus, and Vibrio were dominant in the intestine; Enterobacter, norank_Vicinamibacterales, and Pseudomonas were relatively high-abundance genera in the hemolymph. The composition and abundance of symbiotic microbiota in the hemolymph and hepatopancreas were extremely similar (p > 0.05), and no significant difference in functional prediction was found (p > 0.05). Comparing the hemolymph in the intestine and hepatopancreas, the hemolymph had lower variation in bacterial composition among individuals, having a more uniform abundance of major bacterial taxa, a smaller coefficient of variation, and the highest proportion of shared genera. Network complexity varied greatly among the three sites. The hepatopancreas microbiota was the most complex, followed by the hemolymph microbiota, and the intestinal microbiota had the simplest network. This study revealed the taxonomic and functional characteristics of the hemolymph, hepatopancreas, and gut microbiota in Chinese mitten crab. The results expanded our understanding of the symbiotic microbiota in crustaceans, providing potential indicators for assessing the health status of Chinese mitten crab.

Estimating Density Dependence, Environmental Variance, and Long-Term Selection on a Stage-Structured Life History.

AbstractA method for analyzing long-term demographic data on density-dependent stage-structured populations in a stochastic environment is derived to facilitate comparison of populations and species with different life histories. We assume that a weighted sum of stage abundances, N, exerts density dependence on stage-specific vital rates of survival and reproduction and that N has a small or moderate coefficient of variation. The dynamics of N are approximated as a univariate stochastic process governed by three key parameters: the density-independent growth rate, the net density dependence, and environmental variance in the life history. We show how to estimate the relative weighs of stages in N and the key parameters. Life history evolution represents a stochastic maximization of a simple function of the key parameters. The long-term selection gradient on the life history can be expressed as a vector of sensitivities of this function with respect to density-independent, density-dependent, and stochastic components of the vital rates. To illustrate the method, we analyze 38 years of demographic data on a great tit population, estimating the key parameters, which accurately predict the observed mean, coefficient of variation, and fluctuation rate of N; we also evaluate the long-term selection gradient on the life history.

The efficient calculation methods for stochastic nonlinear transient heat conduction problems

This paper proposes an efficient model reduction strategy in conjunction with non-intrusive statistical moment methods for the stochastic nonlinear transient heat conduction problem. In the proposed strategy, the deterministic reduced basis vectors (RBVs) are adopted to approximate the random temperature response, and the thermal conductivity of the random nonlinear heat conduction matrix in the RBVs space is decoupled from the geometric characteristic matrix (GCM). The computational efficiency of solving the reduced random nonlinear heat conduction models can be enhanced by implementing these two technologies. The large coefficient of variation and the small coefficient of variation stochastic heat conduction problems, respectively, are addressed by the two non-intrusive statistical methods, i.e., the quasi-Monte Carlo method (QMCM) based on number theory and the modified stochastic perturbation method (MSPM). These two methods necessitate deterministic analysis and are easily integrated into the model reduction method. In four numerical instances, the selection of RBVs, the influence of the nonlinear term on the random temperature response, and the accuracy and efficiency of the two non-intrusive statistical moment methods are discussed. The numerical results highlight that the model reduction strategy based on the decoupling of thermal conductivity and GCM, in conjunction with the QMCM and the MSPM, enables the analysis of stochastic nonlinear transient heat conduction problems with a large coefficient of variation and a small coefficient of variation, respectively.

The power balancing benefits of wave energy converters in offshore wind-wave farms with energy storage

With many countries planning to significantly increase grid renewable energy penetration levels, we consider the role of wave energy in supply–demand matching. We investigate how incorporating wave power into an offshore wind farm affects farm power predictability, smoothness, required energy storage capacity, and cost. In this paper, we do a first-order cost analysis of an offshore farm comprised of floating wind turbines and wave energy converters that are both standalone and combined and onshore compressed air energy storage. Then, we do a parameter sweep investigation of an isolated power network supplied by varied grid renewable energy penetration levels supplemented by natural gas, varied distribution of renewable energy between wind and wave power, and varied power capacity of a compressed air energy storage system supplying power to a shoreline community. For each parameter set, we consider the historical hourly electricity demand and wind-sea data of a coastal California community over a year, and optimize the energy storage schedule to reduce curtailed power, stored energy, and base gas plant operational cost. We show that a co-located wind-wave farm has smoother power supply, less energy curtailment, and higher farm-to-grid efficiency than a solely wind farm. That is, a 50%–50% wind-wave farm has a 15% smaller coefficient of variation in the power supply, 6% less curtailed power, and 2% higher farm-grid efficiency than a 100% wind farm when the grid is 100% renewable energy. These benefits of wave power potentially decrease the need for interconnecting regional transmission lines to match power supply with demand. The intent of this paper is to provide baseline system technical results to help future researchers and policy makers make decisions about offshore hybrid wind-wave-storage farms.

Alteration of a brain network with stable and strong functional connections in subjects with schizophrenia

It is widely accepted that there are some common network patterns in the human brain. However, the existence of stable and strong functional connections in the human brain and whether they change in schizophrenia is still a question. By setting 1% connections with the smallest coefficient of variation, we found a widespread brain functional network (frame network) in healthy people(n = 380, two datasets from public databases). We then explored the alterations in a medicated group (60 subjects with schizophrenia vs 71 matched controls) and a drug-naive first-episode group (68 subjects with schizophrenia vs 45 matched controls). A linear support vector classifier (SVC) was constructed to distinguish patients and controls using the medicated patients’ frame network. We found most frame connections of healthy people had high strength, which were symmetrical and connected the left and right hemispheres. Conversely, significant differences in frame connections were observed in both patient groups, which were positively correlated with negative symptoms (mainly language dysfunction). Additionally, patients’ frame network were more left-lateralized, concentrating on the left frontal lobe, and was quite accurate at distinguishing medicated patients from controls (classifier accuracy was 78.63%, sensitivity was 86.67%, specificity was 76.06%, and the area under the curve (AUC) was 0.83). Furthermore, the results were repeated in the drug-naive set (accuracy was 84.96%, sensitivity was 85.29%, specificity was 88.89%, and AUC was 0.93). These findings indicate that the abnormal pattern of frame network in subjects with schizophrenia might provide new insights into the dysconnectivity in schizophrenia.

Varietal Variances of Grain Nitrogen Content and Its Relations to Nitrogen Accumulation and Yield of High-Quality Rice under Different Nitrogen Rates

Nitrogen (N) management is an important strategy for improving the yield, grain quality, and N use efficiency of rice (Oryza sativa). Exploring appropriate N application rates is essential for high-quality rice production in China, especially in the context of the large extension of these varieties in recent years. Field experiments were conducted to study changes of grain N content and their correlations to yield and yield components using twenty high-quality rice varieties grown at three N application rates (105, 165 and 225 kg ha−1) in 2019 and 2020. Additionally, a micro-plot experiment based on 15N isotope tracing technique was also conducted with two contrasting high-quality rice varieties of Y-liangyou 911 and Yeiangyoulisi under two N application rates (165 and 225 kg ha−1) in 2021, with grain N accumulation, its subdivision, and N utilization investigated. We found that the grain N content of high-quality rice increased with the increase of N application rates, while there was no consistent response in grain yield. There was a significant quadratic relationship between grain yield and grain N content, while panicles m−2 and grain-setting rate had a positive and a negative correlation with grain N content, respectively, in both 2019 and 2020. Across three N application rates and two years, the coefficient of variation (CV) of grain N content ranged from 10.36% to 21.26% among twenty varieties, of which Y-liangyou 911 had the smallest CV, and six varieties, including Yexiangyoulisi, had the largest CV. The micro-plot experiment showed that, in comparison with N165, the grain N content, grain N accumulation, and N recovery rate increased under N225 in both varieties, but a significant increase in grain yield was only observed for Y-liangyou 911. Grain N accumulation derived from panicle N fertilizer and its ratios to total grain N accumulation and the N recovery rate was significantly higher than those derived from basal and tillering N fertilizers. Nevertheless, increasing N application rates had much greater effects on the grain N accumulation derived from basal and tillering fertilizers and on ratios to total grain N accumulation in Yexiangyoulisi than those in Y-liangyou 911. Our results suggested that adopting a moderate N application rate (165 kg ha−1) is conducive to maintaining an appropriate grain N content and achieving higher grain yield and N use efficiency as well as better quality of high-quality rice. Besides, moderately reducing basal and/or tillering N fertilizers is necessary for those varieties with a larger CV of grain N content.

Concurrent Validity and Reliability of Sprinting Force-Velocity Profile Assessed With GPS Devices in Elite Athletes.

The aims of this study were to (1) assess the concurrent validity of global positioning systems (GPSs) against a radar device to measure sprinting force-velocity (F-v) profiles and (2) evaluate the interunit reliability of 10-Hz GPS devices (Vector S7, Catapult Innovations). Sixteen male elite U18 rugby union players (178.3 [7.6]cm; 78.3 [13.2]kg) participated. Two 50-m sprints interspersed with at least 5minutes of recovery were completed to obtain input (maximal sprint speed and acceleration time constant τ) and output (theoretical maximal horizontal force, sprinting speed, and horizontal power) F-v profile variables. Sprint running speed was concurrently measured with a radar and 2 GPS units placed on the upper back of each player. Concurrent validity and interunit reliability analyses were performed. Moderate to nearly perfect correlations were observed between radar and GPS-derived F-v variables, with small to large typical errors. Trivial to small coefficients of variation were found regarding the GPS interunit reliability. The GPS devices tested in this study represent a valid and reliable alternative to a radar device when assessing sprint acceleration F-v profiles in team-sport players.

English

Objective: This study aimed to determine the effect of 3-week progressive overloading and 1-week tapering during a preseason on performance, internal training load, stress tolerance, and heart rate variability in under-19 Brazilian badminton players. Material and method: Eight male under-19 badminton players (age 16.1 ± 0.6 years; height 1.68 ± 7.7 m; body mass 57.2 ± 5.8 kg; body mass index 20.3 ± 2.5 kg∙m-2; body fat 8.0 ± 2.7 %), competing at the state level had physical and physiological monitored over four weeks during pre-season. Players underwent a badminton-specific movement agility test, 5-m multiple shuttle test, Yo-Yo Intermittent Recovery test level 1, and performed vertical jumps before and after the pre-season. During the training, the heart rate variability and internal training load were monitored daily, and weekly were stress tolerance was recorded by psychometric responses. Results: The players showed significant improvements in all performance variables assessed after the training period. The internal training load during overloading was higher (1635 ± 109.9; 2490 ± 124; 2850 ± 210 AU) compared to tapering (1335 ± 100 AU). The stress tolerance decreased during overloading (4.0 ± 0.7; 8.2 ± 1.3; 10.1 ± 1.4) and increased during tapering (5.5 ± 1.5). In addition, higher internal training load during overloading resulted in a greater reduction in root-mean-square difference of successive R-R intervals (lnRMSSDmean) (4.2 ± 0.2; 4.1 ± 0.1; 4.0 ± 0.1 ms) and a smaller coefficient of variation (lnRMSSDcv) (4.5 ± 2.6; 2.1 ± 1.2; 1.4 ± 0.9 %), and the significant reduction in the internal training load during tapering led to a decrease in lnRMSSDmean (1.3 ± 0.5 ms). Conclusions: Our results suggest that using badminton training programs during the pre-season, including intermittent high-intensity actions with progressive overloading followed by a tapering is sufficient to result in positive adaptations in performance and led to adaptative changes in internal training load, stress tolerance, and heart rate variability.

Analyzing the within and between Players Variability of Heart Rate and Locomotor Responses in Small-Sided Soccer Games Performed Repeatedly over a Week.

Background: Small-sided games (SSGs) are drill-based and constrained exercises designed to promote a technical/tactical and physiological/physical stimulus on players while preserving some dynamics of the real game. However, as a dynamic game, they can offer some variability making the prediction of the stimulus hardest for the coach. Aim: The purpose of this study was to analyze the between-session and within-player variability of heart rates and locomotor responses of young male soccer players in 3v3 and 5v5 small-sided game formats. Methods: This study followed a repeated-measures study design. Twenty soccer players were enrolled in a study design in which the SSG formats 3v3 and 5v5 were performed consecutively across four days. Twenty under-17 male youth soccer players (16.8 ± 0.4 years old) voluntarily participated in this study. Participants were monitored using a Polar Team Pro for measuring the heart rate mean and maximum, distances covered at different speed thresholds, and peak speed. Results: Between-players variability revealed that maximum heart rate was the outcome with a smaller coefficient of variation (3v3 format: 3.1% to 11.1%; 5v5 format: 6.6% to 15.2%), while the distance covered at Z5 (3v3 format: 82.5% to 289.8%; 5v5 format: 94.0% to 221.1%). The repeated measures ANOVA revealed that the four games tested were different in the within-player variability considering the maximum heart rate (p = 0.032), total distance (p < 0.001), and distances at zone 1, 2, and 5 of speed (p < 0.001). Conclusions: The smaller small-sided game tested promotes greater within-player variability in locomotor demands while promoting smaller within-player variability heart rate responses. Possibly, 5v5 is more recommended to stabilize the locomotor demands, while the 3v3 is recommended to stabilize the heart rate stimulus.

Evaluation of the start of surgical closure as a milestone for forecasting the time remaining to exit the operating room: A retrospective, observational cohort study

IntroductionForecasting when patients will exit the operating room (OR) is important for managing add-on cases, coordinating breaks and relief, anticipating postanesthesia care unit admissions, and estimating to-follow surgeons’ start times. If coefficients of variation (CVs) for the interval from closing to OR exit (OR exit interval) were small, a reasonable predictive approach would be to initialize a timer at the start of closing using the mean OR exit interval, then decrement the time remaining each successive minute. However, if the CV were ≥0.32 (typical for many surgical procedure times), this approach would be invalid because actual average times remaining would significantly exceed the predictions. Futility would be expected because the corresponding approach is inaccurate for case duration prediction. MethodsWe retrospectively studied all OR anesthetics (n = 44,254) at an adult academic hospital from October 29, 2017, through January 11, 2022. The primary surgeon, scheduled primary Current Procedural Terminology code, OR entry to closing, and OR exit intervals were retrieved electronically. The CVs of the OR exit intervals were calculated, categorized by: primary CPT and surgeon; primary CPT; American Society of Anesthesiologists CPT; and Clinical Classification Software category. We compared, pairwise, the standard deviations (SD) of the OR entry to closing interval to the OR exit interval, determined if most (>50%) of the CVs for the OR exit interval were ≥0.32, and compared CVs for the OR exit interval among categories. We analyzed categories that were performed ≥30 times. ResultsFor all categories, the standard deviations (SD) of the OR exit intervals were considerably smaller than the paired SDs of OR entry to closing (P < 0.0001). The smallest CVs were from combining primary CPT and surgeon (median 0.4, IQR 0.34 to 0.47, P < 0.0001 vs. other categories). However, using the 244 analyzed combinations of primary CPT and surgeon, the best classification category, 81.3% of the CV (99% CI 74.1% to 87.2%, P < 0.0001) were ≥0.32. In other words, at least 74% of combinations would have greater proportional variability than observed commonly for surgical times. ConclusionsA simple timer started when surgical closure begins, decrementing each subsequent minute, is an invalid approach to estimating the time remaining in cases once closure begins. Rather, previously published methods for predicting the time remaining in ongoing OR cases are appropriate, with time-zero set when closing begins. OR status boards would be updated continually with the revised exit times, calculated as the current time plus the time remaining.

Cumulative residual symbolic dispersion entropy and its multiscale version: Methodology, verification, and application

In quantifying the complexity characteristics of neurophysiological signals, the most advanced entropy methods still have some inevitable limitations of poor accuracy, robustness, and reliability. To solve these limits, this study proposes a novel entropy estimator, termed cumulative residual symbolic dispersion entropy (CRSDE). Meanwhile, a corresponding multiscale variant, time-shift cumulative residual symbolic dispersion entropy (TCRSDE), is introduced to quantify the time series's irregularity on multiple time scales. The CRSDE starts with an improved symbolic dynamics filter (ISDF) based on the equal probability dividing criterion, mapping a raw time series to symbolic series. Next, embedding theory is applied to derive the dispersion patterns. Finally, the cumulative residual probabilities of all dispersion patterns are counted, and corresponding CRSDE results are calculated. A series of performance validations are executed using synthetic and real-world datasets. The simulation results confirm CRSDE's optimal estimation accuracy and robustness to noise and data length. The findings of EEG dataset demonstrate that CRSDE could realize the best reliability with the lowest root mean square deviation (RMSD; <0.05). In the multiscale version, TCRSDE, a time-shift coarse-graining is introduced. The verification findings confirm that the TCRSDE can avoid incorrect estimates and achieve the best-estimated stability on all scales with the smallest coefficient of variation (CV; <0.01) and shortest running time. Finally, CRSDE method is applied to neonatal sleep EEG. Compared to other methods, CRSDE shows the most significant differences, with all p-values less than 0.01 via a nonparametric Mann-Whitney U test. Meanwhile, CRSDE obtains the highest Hedges' g effect size values and least outliers at three sleep stages. Therefore, CRSDE performs best in quantifying neurodynamics of neonatal sleep stages.

Iterated local search for the placement of wildland fire suppression resources

We consider the problem of, given a landscape represented by a gridded network and a fire ignition location, deciding where to locate the available fire suppression resources to minimise the burned area and the number of deployed resources as a secondary objective. We assume an estimate of the fire propagation times between adjacent nodes and use the minimum travel time principle to model the fire propagation at a landscape-level. The effect of locating a resource in a node is that it becomes protected and the fire propagation to its unburned adjacent nodes is delayed. Therefore, the problem is to identify the most promising nodes to locate the resources, which is solved by a novel iterated local search (ILS) metaheuristic. A mixed integer programming (MIP) model from the literature is used to validate the proposed method in 32 grid networks with sizes 6x6, 10x10, 20x20 and 30x30, with two different number of fire suppression resources (64 problems). Our ILS produced optimal solutions in 40 cases out of 41 known optimal lower bounds. The proposed method’s effectiveness is also due to its short computing times and small coefficients of variation of the objective function values.We also provide a categorised literature review on fire suppression deterministic optimisation models, from which we conclude that approximate collaborative approaches seldom have been applied in the past and, according to the results obtained, can successfully address the complexity of fire suppression, reaching good quality solutions even for large scale instances.

A new method to determine the crack closure stress based on stress difference

Crack closure stress is a key stress threshold of rocks under compression, the determination of which is of great significance to the evaluation of macroscopic deformation behavior and microscopic fracture evolution characteristics of rocks. Based on the applicability and analysis of the existing methods, a novel method called axial stress difference (ASD) method on the basis of axial stress - axial strain curve is proposed. This method reduces the dependence on the elastic modulus which restricts the promotion of previous methods, and can objectively acquire the crack closure stress by the identification of the onset point of linearly elastic stage of axial stress - axial strain curves. Then, the crack closure stress of rock materials under uniaxial and triaxial compression obtained by the ASD method is compared with the counterparts from other methods. The results obtained by the ASD method are close to that by other methods, which can also be verified by the small standard deviation and coefficient of variation. Since the International Society for Rock Mechanics and Rock Engineering (ISRM) has not yet recommended standard methods for solving the crack closure stress, this method can be an effective supplement to the existing methods.

The ektacytometric elongation Index (EI) of erythrocytes, validation of a prognostic, rheological biomarker for patients with sickle cell disease.

Validation of the measurement of erythrocyte deformability as a useful prognostic, rheological biomarker for patients with sickle cell disease (SCD). The degree of reduced deformability was based on the value of the maximum elongation index (EImax ) of the deformability curve of an osmotic gradient ektacytometer. The performance of this technique was analytically and clinically validated by analysing 200normal subjects and 100patients with well-documented thalassemia's and Hb variants in relation to their clinical condition. In this study, we show that EImax is a reproducible parameter with a small inter-individual coefficient of (Biological) variation (CV)=1.6% and a small intra-individual CV=3.5%. We demonstrate that loss of deformability correlates with the clinical condition and the various mutations underlying sickle cell disease and thalassemia. For SCD patients, a strongly reduced EImax with a cut-off =0.360 is a signal for future vaso-occlusive (VOC) events requiring hospitalisation with a specificity=85%, sensitivity=80%, PPV=81% and NPV=84% based on a ROC curve (AUC=0.89). This study validated the clinical utility of EImax as a prognostic marker for future clinical problems in individual high-risk SCD patients. In addition, EImax may help to achieve an adequate personal transfusion policy for an optimal blood flow in anaemic patients with SCD.

Improved performance of flexible citrus resistive memory device through air plasma

Flexible natural material-based electronics have attracted considerable attention because it can be applied in wearable applications and bio smart electronics. Natural material citrus is used as the dielectric layer in this work to develop flexible resistive switching memory devices, with plasma ITO surface as the bottom electrode (BE) to investigate the effects of air plasma on device performances. The work function difference between the top electrodes (TE) and BE can be increased with plasma treatment. After optimization, the flexible citrus resistive memory device with a large work function difference between the TE and BE exhibits a good ON/OFF ratio of larger than 103, a low set voltage of around 0.76 V, uniform distribution of set voltages, small coefficients of variation of high resistance state, and low resistance state currents, and a long retention time of more than 104 s. The air plasma can also modify the ITO surface to make the surface more hydrophilic. Thus, the citrus film is easier to attach to ITO, which improves the bending performance of the device. The device under a bending radius of 4.9 mm showed no significant ON/OFF ratio changes when compared with that of the flat state. This information on the correlation between the plasma treatment time and the work function of the ITO electrode would be very useful in obtaining stable and uniform resistive switching properties in the flexible natural material-based resistive memory.