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REM sleep is known to be closely associated with behavioral problems in children. Our previous study showed that children with decreased REM sleep (REM 10%) suffered from severe sleep-disordered breathing (SDB). In this study we explored the characteristics of behavioral problems in children with SDB and decreased REM sleep.A total of 223 children were enrolled in the study. Sleep was evaluated by Polysomnography (PSG). Behavioral problems were assessed by a Chinese version of Child Behavior Checklist (parent-reported). Parameters of SDB and behavioral problem scores (internalizing, externalizing, and total scores) were compared between the children with decreased REM (REM 10%) and those with REM ≥ 10% before and after controlling overweight/obesity and obstructive sleep apnea hypopnea syndrome (OSAHS). Parameters of SDB were also compared between the normal behavior group and the abnormal behavior group. The correlation between the behavioral problems and the sleep parameters was analyzed.The children with decreased REM sleep (10%) had more severe externalizing and total behavioral problems, even when controlled for overweight/obesity. The abnormal behavior group had significantly shorter total sleep time and REM sleep compared to the normal behavior group.Children with SDB and decreased REM sleep showed more severe behavioral problems, especially the externalizing behavioral problems. The behavioral problems can be aggravated by insufficient total sleep. Decreased REM sleep in children may be an independent parameter that is associated with the behavioral problems in children with SDB.

A series of low carbon steel specimens is investigated in the frame of a chain of magnetic non-destructive measurements on round robin samples, organized by the Universal Network for Magnetic Non-Destructive Evaluation. The samples have been plastically deformed by cold rolling to five consecutive stages of deformation. They were examined by several different nondestructive magnetic methods and the results were compared with each other and with the destructive mechanical measurements of Vickers hardness and ductile-brittle transition temperature. Very well correlated and qualitatively very similar relations between the magnetic and mechanical parameters were found in all cases, and for all the methods. Difference between the results of different measurements was found only in the sensitivity of the measurement with respect to the independent parameter, which is a promising message for the potential practical applications and possible future standardization of magnetic nondestructive methods.

Irregular interdigitated morphology is prevalent in biological sutures in nature. Suture complexity index has long been recognized as the most important morphological parameter to govern the mechanical properties of biological sutures. However, the suture complexity index alone does not reflect all aspects of suture morphology. The goal of this investigation was to determine that besides suture complexity index, whether the degree of morphological irregularity of biological sutures has influences on the mechanical properties, and if there is any, how to quantify these influences. To explore these issues, theoretical and finite element (FE) suture models with the same suture complexity index but different levels of morphological irregularity were developed. The quasi-static stiffness, strength for damage initiation and post-failure process of irregular sutures were studied. It was shown that for the same suture complexity index, when the level of morphological irregularity increases, the overall strain to failure will increase while tensile stiffness is retained; also, the total energy to fracture increases with a sacrifice in strength to damage initiation. These results reveal that morphological irregularity is another important independent parameter to govern and balance the mechanical properties of biological sutures. Therefore, from the mechanics point of view, the prevalence of irregular suture morphology in nature is a merit, not a defect.

A comprehensive database of the polyaxial compressive strength of eight sandstones has been compiled from the literature. An experimental study has also been conducted on local sandstone to add up to the database. A correlation-based analysis has been performed to find out the influence of each independent parameter namely uniaxial compressive strength (UCS, σci), minor principal stress (σ3), and intermediate principal stress (σ2) on the strength of sandstone, i.e., the major principal stress at failure (σ1). Additionally, a feed-forward back-propagating neural network (FFBPNN) has been proposed as a new polyaxial strength model to predict the strength of intact sandstone under polyaxial states of stresses. The database on polyaxial strength of 192 experiments on nine different sandstones has been randomly divided into a training set and a testing set. Three input parameters corresponding to the independent parameters (σci, σ3, σ2) and one output parameter corresponding to the dependent parameter (σ1) are considered. The accuracy of the proposed ANN based polyaxial strength model has been compared with five other conventional polyaxial criteria: modified Wiebols and Cook criterion (MWC), Mogi-Coulomb criterion (MC), modified Lade criterion (ML), 3D version of Hoek-Brown criterion (3DHB) and modified Mohr–Coulomb criterion (MMC). It is found that the ANN based failure model gives the best result amongst all the considered polyaxial strength criteria, for the testing dataset.

Subsurface geological formation properties often involve some degree of uncertainty. Thus, for most conditions, uncertainty quantification and data assimilation are necessary for predicting subsurface flow. The surrogate model based method is one common type of uncertainty quantification method, in which a surrogate model is constructed for approximating the relationship between model output and model input. Based on the prediction ability, the constructed surrogate model can be utilized for performing data assimilation. In this work, we develop an algorithm for implementing an iterative ensemble smoother (ES) using the surrogate model. We first derive an iterative ES scheme using a regular routine. In order to utilize surrogate models, we then borrow the idea of Chen and Oliver (2013) to modify the Hessian, and further develop an independent parameter based iterative ES formula. Finally, we establish the algorithm for the implementation of iterative ES using surrogate models. Two surrogate models, the PCE surrogate and the interpolation surrogate, are introduced for illustration. The performances of the proposed algorithm are tested by synthetic cases. The results show that satisfactory data assimilation results can be obtained by using surrogate models that have sufficient accuracy.

Coalescence modelling in liquid/liquid dispersions is a challenging task and field of investigations up to now, which becomes apparent when comparing the various existent models with their different and partly even contradictive implementation of influencing factors. In this work, systematic investigations of single drop coalescence were used to compare and validate different coalescence efficiency models regarding the important influencing parameters relative collision velocity and drop size. The impact of these parameters could be analysed independently from each other for the first time and used to identify the best modelling approach. Moreover, the numerical parameter of the coalescence efficiency model could be obtained based on single drop experiments. Using this determined parameter the simulation of drop size distributions within a lab scale stirred vessel was possible. The presented method offers the possibility of independent parameter estimation for population balance equation simulations based on single drop experiments. The application of this systematic approach allows the separate validation of submodels and reliable parameter determination by small scale investigations. On this basis a sound scale-up is possible using population balance equation simulations. (C) 2016 Elsevier Ltd. All rights reserved.

The performance of ductile fracture criteria often depends on the accuracy of material constants identification. Calibration process of three uncoupled phenomenological models was analysed. All of them contain the strain hardening exponent which is related to material plasticity as one of the fracture criteria parameter. More flexibility, better approximation of the fracture locus and more convenient shape of the fracture envelope might be reached when the strain hardening exponent is considered as another independent parameter of the fracture criteria in the identification process. Results are illustrated on the example of two structural steels, AISI 316L and AISI 1045, respectively.

Morris water maze has been widely used for analysis of cognitive functions and relies on the time taken by animal to find the platform i.e. escape latency as a parameter to quantify spatial memory and learning. However, escape latency is confounded by swimming speed which is not necessarily a cognitive factor. Rather, path length may be a more appropriate and reliable parameter to assess spatial learning. This paper presents fractal dimension as a new paradigm to assess spatial memory and learning in animals. Male wistar rats were administrated with pentylenetetrazole and scopolamine to induce chronic epilepsy and dementia respectively. Fractal dimension of the random path followed by the animals on Morris water maze was analyzed and statistically compared among different experimental groups; the results suggest that fractal dimension is more reliable and accurate parameter to assess cognitive deficits compared to escape latency. Thus, the present study suggests that fractal dimensions could be used as an independent parameter to assess spatial memory and learning in animals using Morris water maze.

The decision to design a frame structure to bridge over a column lost due to accidental loading has obvious impacts on construction costs. Moreover, not all structures are potential targets of hazards likely leading to column loss events. In this context, we propose a formulation for risk-based cost-benefit analysis of design for load bridging over failed columns. The formulation combines normal with abnormal loading conditions, treating column loss probability as an independent parameter. The proposed formulation is employed in design of continuous beams, typical RC floors and regular frame structures. The study reveals the conditions for load bridging design in frame structures to be cost-effective. We show that column loss probabilities play a major role in optimal design and reinforcement decisions. The proposed formulation allows optimal design of frame structures addressing competition between failure modes. Under discretionary column removal, competition between local bending and local pancake failures is typical of regular frame buildings, as stronger beams favor pancake compression failures.

Introduction Previous auditory experience modifies the sensitivity of the auditory cortex to the afferent activity of the auditory pathways and may influence the threshold (T) and comfort (C) levels in patients receiving a cochlear implant (CI). Literature data on this particular topic is very scarce. Objective This study aimed to evaluate the differences in T/C-levels between pre- and postlingually implanted cochlear implant patients. Methods Retrospective case review in a quaternary otologic referral centre was performed. Data on the T/C-levels have been collected in 90 consecutive CI patients divided into 2 groups. Group 1 comprised 16 prelingually deaf children implanted between 8 months and 10 years of age. Group 2 comprised 74 postlingually deaf adults (average age of 62 years). All patients were users of the Nucleus 24RECA (Freedom, Contour Advance-of-Stylet electrode) cochlear implant. All measurements were performed at the fifth implant programming session at 4–6 months after surgery, when stable T/C thresholds have already been obtained. Results The behavioural C-levels present important and statistically significant differences between the pre- and postlingually implanted patients for all electrode contacts that could reach 30 CL. For the T-levels the observed differences were smaller and statistically insignificant for most electrode contacts. Conclusions The previous auditory experience (pre- or postlingual deafness) seems to be an independent parameter influencing the T/C-levels in patients receiving a CI. Together with the electrode contact impedance and the contact position in the electrode array it can explain up to 37% of the variability in the definition of the C-levels. The fact that the stabilised C-levels measured 4–6 months postoperatively can be up to 30 CL higher in the prelingually deaf patients than in the postlingual ones results also in a much higher dynamic range observed in prelingual subjects. Therefore implant programming of the prelingual patients should be very cautious in order to avoid the risk of overstimulation.

The paper describes the influence of forming-induced residual stresses in stainless steel SHS (Square Hollow Sections) on both the material itself and the behaviour of compressed members. The residual stress contribution to the stress–strain diagram concerning the initial modulus of elasticity and non-linearity is shown by the comparison of as-delivered and stress-relieved material. An analytical model covering the influence of residual stresses on material behaviour was developed and verified numerically. The FE study using the Abaqus software determines the influence of residual stresses in compressed members both on local and global buckling. Finally, the study on behaviour of member includes the influence of a varying degree of material non-linearity as an independent parameter representing the behaviour of various steels in long and stub columns with residual stresses.

Exponential random graph models were used to assess the relevance of reciprocity, popularity, transitivity controlling for effects based upon ego and alter sex, and sex homophily, on the formation of affiliative ties in 19 Portuguese preschool peer groups. The number of times two children were recorded as nearest neighbors in focal samples was used as an indicator of the relationship's strength. Independent parameter estimates of the different models (one for each group) were summarized, separately for the three age groups (“3-year-olds”, “4-year-olds” and “5-year-olds”) using a multi-level approach to meta-analysis. Results showed that affiliative ties between children were sex segregated, highly reciprocal, more likely to be directed to a restricted number of children and with a tendency to create transitive triads. The structural processes underlying the formation of affiliative ties were quite stable between classrooms.

The limit cycle of the Duffing–van der Pol equation x ¨ + x + e ( x 2 - 1 ) x ˙ + δ x 3 = 0 is studied. By considering the product of the frequency ω of the limit cycle and the coefficient e as an independent parameter μ = e ω , an equivalent equation is obtained and then solved by Liao’s homotopy analysis method. The frequency ω is deduced as a function of μ and δ . This function provides us with an algebraic equation for ω , according to which we have an analytical approximation for the frequency. Numerical examples show that the attained approximation is very accurate. More importantly, the results are uniformly valid for all positive values of e .

Modelling, performance analysis, and designing of solar energy systems depend on solar radiation data. In this study, a simple model for estimating the daily global radiation is developed. The model is based on a trigonometric function, which has only one independent parameter, namely the day of the year. The model is tested for 68 locations in Turkey using the data measured during at least 10 years. It is seen that predictions from the model agree well with the long-term measured data. The predictions are also compared with the data available in literature for Turkey. It is expected that the model developed for daily global solar radiation will be useful to the designers of energy-related systems as well as to those who need to estimates of yearly variation of global solar-radiation for any specific location in Turkey. © 2006 Elsevier Ltd. All rights reserved.

Two of the most important structural controls on the properties of borosilicate glasses and glass melts are the variation between three- and four-coordination of network-forming boron cations, and the extent of mixing of Si and B. The effects of composition on these key parameters are relatively well studied. However, proposed mechanisms could be better constrained by testing with another, independent parameter that can also strongly affect the network. Here we present some of the first quantitative structural data on the effects of high pressure on the network structure of a sodium borosilicate glass. Using high-resolution 11 B and 17 O NMR on a sample melted at 5 GPa, we demonstrate that the formation of tetrahedral boron from trigonal boron is indeed closely coupled to the conversion of non-bridging to bridging oxygens. The increased fraction of tetrahedral boron at high pressure also causes increased mixing of boron and silicate structural units, as oxygens bridging between two BO 4 groups are energetically relatively unfavorable.

The luminous efficacy of global solar radiation for clear skies has been modeled using solar elevation as the only independent parameter. In the present work, two types of models are developed. On the one hand, polynomial models similar to those presented by other authors are produced, and on the other, a non-polynomial model for the luminous efficacy of global solar radiation is reported, as obtained from the ratio between the corresponding illuminance and irradiance models. This last mentioned model offers an accuracy to predict global illuminance similar to that obtained with the polynomial models. However, the model for the global efficacy obtained from illuminance and irradiance models has, among others, the advantage of its mathematical coherence, and its formulation uses a more definite function than the polynomial models.

The relationship between bioconcentration factors and molecular connectivity indices was investigated. A regression model was developed using 80 measured BCFs of nonpolar organic pollutants. The five topological parameters used were 1 χ, 2 χ, 3 χ 0 χ v and 2 χ v . Modified jackknife tests were applied to examine the robustness of the model by repeatedly removing a set of or a class of compounds from the database. The model was compared with one using Kow as an independent parameter. The mean absolute errors for the 80 compounds studied were 0.288 and 0.302 log-unit for the two models, respectively.

We investigate effects of spontaneous breakdown of CP in $B^0_{d,s}-\overline{B^0}_{d,s}$ systems in left-right symmetric models. Assuming that the left-right contribution to the $B^0-\overline{B^0}$ matrix element $M_{12}$ can be at most equal to the standard model one we obtain a new lower bound, $M_H\gsim 12$ TeV, on the flavour changing Higgs boson mass. Most importantly, the convention independent parameter $Re(\overline{\epsilon}_B),$ which measures the amount of $\Delta B=2$ CP violation, can be enhanced by a factor of four or more for $B^0_d$ and almost by two orders of magnitude for $B^0_s$ systems when compared with the Standard Model predictions. Therefore, interesting possibilities to observe indirect CP violation in the $B$ system are open in the planned facilities.

Within the framework of the dipole approximation the line-shape of light absorption for exciton transitions between narrow bands in one-, two- and three-dimensional periodic structures are calculated. Exciton damping due to lattice imperfections is accounted for as a frequency independent parameter. The obtained analytical expressions allow analysis of the line-shape for different space dimensions of structure depending on bandwidth difference, damping and temperature.

The effect of the initial droplet-size distribution (DSD) on spray combustion processes has been studied experimentally. Suitable flames were produced by igniting ethanol sprays issuing from a pipe into a coannular air stream. Three different DSDs were examined for their effect on spray combustion processes, while the initial Sauter mean diameter (SMD or D 32 ), mixture ratio, and gas/liquid velocities were held constant. Variations in spray/flame structure resulting from changes in the DSD were determined by measuring droplet sizes and velocities, and gas temperature and composition, within the reacting spray field. The results show that more complete combustion occurs in sprays possessing narrower DSDs, even with the SMD held constant. Reductions in the burning efficiency of sprays with wider DSDs is attributed primarily to their greater relative population of large fuel droplets and to droplete-size-segregating effects occurring at the spray periphery, which affect mixing rates. The results establish the DSD as an important indicator of atomization quality and an independent parameter regarding spray combustion processes.

Objective: The purpose of this study was twofold: (1) to evaluate the relationship between fetal heart circumference and gestational age and (2) to determine the effect, if any, of disturbances in fetal growth on heart circumference. Study design: Heart circumference was measured in 262 women with normal gestations (control group) and in two study groups consisting of 52 large-for-gestational age 32 small-for-gestational age fetuses. Standardized, gestational age-adjusted values in the two study groups were compared with normative data provided by the control group. Results: There was a close correlation ( R 2 = 0.94) between heart circumference and gestational age in normally growing fetuses. Disturbances of fetal growth (i.e., macrosomia and growth retardation) were found to have an inconsistent effect on heart circumference. Conclusion: Heart circumference cannot be used as an independent parameter for gestational age evaluation in fetuses with disturbances of growth.

Modulation is one of the most important electrical parameters for floppy disks. It is not only a measurement of the uneveness of the output signal amplitude but also a measurement of the reliability of the end products. In this paper the influence of the principal factors on the modulation is discussed. They are the surface smoothness, defects of the media and the quality of the assembly, as well as the orientation mode of magnetic particles in the media layer. The modulation is not an independent parameter. It is closely related to the other electrical ones of floppy disks. Among different expressions of modulation, negative modulation is the most sensitive for above factors.

Salot and Gude have provided interesting data in their recent article in your esteemed journal. Smad7 may significantly influence clinical prognosis in a number of other malignancies especially gastrointestinal malignancies. Smad7 influences clinical prognosis in oesophageal malignancies. Decreased survival rates are seen in association with Smad7 expression. Not surprisingly, a poor clinical outcome is seen in oesophageal carcinomas with positive Smad7 expression. A similar association is seen in gastric malignancies. Nearly 32% of all gastric malignancies express Smad7. A close association exists between the Lauren classification and the Smad7 expression by the tumour. Smad7 is in fact an independent parameter influencing clinical prognosis in gastric carcinomas. Patients positive for Smad7 tend to have shorter survival rates. Smad7 also influences clinical prognosis in colo-rectal malignancies. Smad7 deletion results in improvement in disease free survival as well as overall survival. Loss of Smad7 expressing cells makes the tumour more susceptible to transforming growth factor-beta (TGF-beta). A similar relationship is seen in pancreatic adenocarcinomas. Nearly, 71% of pancreatic adenocarcinomas are positive for Smad7. In patients who undergo surgical intervention the margin

Free energy differences between similar systems can be calculated by an integration technique due to Kirkwood, in which a Hamiltonian is constructed which varies continuously through functions intermediate between the initial and final functions according to the value of an independent parameter. A calculation for Lennard-Jones interactions using a Hamiltonian non-linear in the independent parameter is shown to converge much more rapidly than a linear parameterization, the latter having generally been used in calculations of this kind in the literature.

Orthogonality of Walsh functions is used to obtain independent parameter estimation equations for continuous-time dynamic systems. The conditioning of these equations is optimized by use of optimum inputs and is based on maximizing analytic non-linear functions of Walsh coefficients. It is shown that an optimum data shift procedure can be used to optimize the estimation of time-delay and control gain.

A microscopic folding formalism using a separable potential approach is applied to the elastic scattering of the n-α system. Starting with a separable nucleon-nucleon (NN) potential model, a sum of separable nueleon-nucleus potentials is obtained. A simple structure of the α-particle is assumed and the Tabakin, the Doleschall and the Strobel N N potentials are considered. These phenomenological interactions are of Yukawa or gaussian form with variable parameters for each partial wave. Spin-orbit and tensor forces are included. The resulting potentials developed from our folding calculations give approximately the same S 1 2 phase shifts for the n-α elastic scattering. However, in the p 1 2 and p 3 2 phase-shift analysis, an effective interaction derived from the NN potential is necessary to reproduce the resonances. One free energy independent parameter is introduced in our approximate G -matrix concept to give a good fit for the phase shifts. Single-nucleon knockout exchange (SNKE) is considered throughout.

Based upon independent parameter reliability and minimum sample size evaluations, a sample size of 25 trials was identified as necessary to provide accurate ground reaction force (GRF) data describing a subject's running performance. Intraday parameter reliability based on this sample size was approximately 75% indicating that subject variability must be acknowledged when comparing the effects of different running shoes. The minimum differences in GRF parameter values that are biomechanically significant have been estimated at 1 N/kg and 2% for force and relative temporal measures, respectively.

Slip effects in plane porous journal bearings are considered realistically: only the slip coefficient is treated as an independent parameter and the porosity and the ratio of clearance to journal radius are the other factors which determine the effects of slip. The effects of velocity slip on the static performance as well as on the dynamic performance of the bearings are determined.

Within the framework of the dilute-gas approximation, the instanton gas with a dipole-like interaction is studied, including the hard-core repulsion necessarily implied by the consistency of this approximation. We are led to a new, self-consistent scheme of instanton calculations provided by a cooperative suppression of large instantons instead of the usual ad hoc infrared cut-off. Diluteness is brought under better control by a single, regularization prescription independent parameter. Functional methods known from statistical mechanics are used to treat the hard-core and dipole interactions simultaneously. The permeability is calculated and used to discuss the Gell-Mann-Low β-function in the intermediate coupling range. The results are confronted with recent lattice calculations.

One-minute measurements of horizontal diffuse, Dh, and global, Gh, solar radiation components were used to calculate Kd and these ratios were compared with values determined from previously published functions of the independent parameter Kt. The spectrum of the 9906 ratios, used in the comparison, was taken from representative days with percent sunshine ranging from 10 to greater than 90 per cent and from different seasons. The results of this comparison show that Kd is not accurately determined by these functions of Kt alone and from functions fitted to our data, and suggest that other parameters might be needed. The calculation of global radiation on a tilted surface from models which depend on Dh were also analyzed by comparisons with global tilt radiation measured at 45° and 90° tilt angles at each of the four cardinal directions. The poor determination of Kd causes large scatter in calculated global tilt radiation values because of the corresponding poor value of Dh. However, if a good value of Dh is used then the global tilt models replicate measured global tilt radiation values to within 10 per cent.

An attempt has been made to relate the properties of uranyl hydrolytic complexes in solution and hydrolytic precipitates. All data have been expressed in terms of the independent parameter NaOH/U (degree of alkalization, i.e. molar ratio of hydroxide added to total uranium). All fundamental properties found may be explained by assuming that hydrolytic complexes in liquid as well as in solid phase are not higher than dinuclear, containing nonequivalent hydroxyl groups.

Another closed form expression for the static structure factor of dense fluids, in the generalized Ashcroft Lekner hard sphere model, is presented. It incorporates the correct hard sphere equation of state given by Carnahan and Starling. This model has, as usual, one independent parameter which can be adjusted by a fit to the experimental data at one point.

The Ashcroft-Lekner hard-sphere model for the calculation of the structure factor is generalized to take into account a correct hard-sphere equation of state. The model has one independent parameter which can be adjusted by a fit to the experimental data at one point.