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BACKGROUND/OBJECTIVES: Prediction equations are commonly used to estimate body fat from anthropometric measurements, but are population specific. We aimed to establish and validate a body composition prediction formula for Asian newborns, and compared the performance of this formula with that of a published equation. SUBJECTS/METHODS: Among 262 neonates (174 from day 0, 88 from days 1-3 post delivery) from a prospective cohort study, body composition was measured using air-displacement plethysmography (PEA POD), with standard anthropometric measurements, including triceps and subscapular skinfolds. Using fat mass measurement by PEA POD as a reference, stepwise linear regression was utilized to develop a prediction equation in a randomly selected subgroup of 62 infants measured on days 1-3, which was then validated in another subgroup of 200 infants measured on days 0-3. RESULTS: Regression analyses revealed subscapular skinfolds, weight, gender and gestational age were significant predictors of neonatal fat mass, explaining 81.1% of the variance, but not triceps skinfold or ethnicity. By Bland-Altman analyses, our prediction equation revealed a non-significant bias with limits of agreement (LOA) similar to those of a published equation for infants measured on days 1-3 (95% LOA: (- 0.25, 0.26) kg vs (- 0.23, 0.21) kg) and on day 0 (95% LOA: (- 0.19, 0.17) kg vs (- 0.17, 0.18) kg). The published equation, however, exhibited a systematic bias in our sample. CONCLUSIONS: Our equation requires only one skinfold site measurement, which can significantly reduce time and effort. It does not require the input of ethnicity and, thus, aid its application to other Asian neonatal populations. European Journal of Clinical Nutrition (2013) 67, 922-927;doi: 10.1038/ejcn.2013.69;published online 3 April 2013 Keywords: body composition; neonatal fat mass; prediction equation; skinfolds, INTRODUCTION Excess adiposity is a major risk factor for adverse health outcomes and chronic diseases. (1) Body fat assessment in infants is important not only as an indicator of nutritional [...]

ABSTRACT Diabetic nephropathy (DN) characterized as nephrotic syndrome and diffuse glomerulosclerosis can cause renal failure and end-stage kidney disease. Expansion of mesangial matrix around capillaries in the kidney glomeruli is [...]

The underlying cause of loose fill slope failures in Hong Kong has been attributed to static liquefaction during heavy rainfall. A series of centrifuge model tests and numerical analyses were conducted to illustrate that instability of a fill slope inclined at approximately the internal friction angle of the soil can be triggered by confined groundwater flow due to soil layering in the fill slope. The results also showed that slope failure could occur irrespective of the density of the fill material when seepage was sufficiently impeded leading to a localised buildup of pore-water pressure in the slope. A numerical parametric study was carried out to examine the effect of variations in hydraulic conductivity in the layered fill slopes. The results showed that the excess pore pressure distribution and hence the failure mode were strongly dependent on the location of the inhomogeneous soil layers and their hydraulic properties. It was also demonstrated that layered fill slopes with spatial variation in hydraulic conductivity of as small as one order of magnitude were vulnerable to global failure under confined groundwater flow. Key words: loose fill slope, static liquefaction, inhomogeneous, confined groundwater flow. La cause sous-jacente des ruptures de talus de remblayages meubles a Hong Kong a ete attribuee a la liquefaction statique durant les fortes pluies. Une serie d'essais sur modele au centrifuge et d'analyses numeriques ont ete realises pour illustrer que l'instabilite d'un talus de remblai incline approximativement a l'angle de frottement interne du sol peut etre de clenchee par une infiltration confinee d'eau souterraine due a la presence de sols en couches dans la pente du remblai. Les resultats ont aussi demontre que la rupture de la pente pouvait se produire independamment de la densite du materiau du remblai lorsque l'infiltration etait suffisamment entravee au point de developper une pression interstitielle localisee dans la pente. On a realise une etude parametrique numerique pour examiner l'effet des variations de la conductivite hydraulique dans les pentes de remblais stratifies. Les resultats montrent que la distribution de l'excedent de pression interstitielle et ainsi le mode de rupture etaient fortement dependants de la localization de l'heterogeneite des couches de sol et de leurs proprietes hydrauliques. On a aussi demontre que les pentes de remblai stratifie avec une variation spaciale dans la conductivite hydraulique d'un aussi faible ordre de grandeur etaient vulnerables a la rupture globale lorsque soumises a un ecoulement d'infiltration confine d'eau souterraine. Mots-cles : pente dans un remblai meuble, liquefaction statique, heterogeneite, ecoulement confine d'eau souterraine. [Traduit par la Redaction], Background Static liquefaction in loose fill slopes Slope failures often occur in tropical areas due to prolonged periods of heavy rainfall. Hong Kong is in a tropical area with a [...]

Byline: G. Kerschen (Department of Aerospace and Mechanical Engineering (LTAS), University of Liege, Belgium, g.kerschen@ulg.ac.be); A.F. Vakakis (Division of Mechanics, National Technical University of Athens, Greece Department of Mechanical and [...]

This paper presents a swept envelope approach to determining the optimal tool orientation for five-axis tool-end machining. The swept profile of the cutter is determined based on the tool motion. By analyzing the swept profile against the part geometry', four types of machining errors (local gouge, side gouge, rear gouge, and global collision) are identified. The tool orientation is then corrected to avoid such errors. The cutter's swept envelope is further constructed by integrating the intermediate swept profiles, and can be applied to NC simulation and verification. This paper analyzes the properties of the swept profile of a general cutter in five-axis tool-end machining. The relation of the swept profile, the part geometry, the tool motion, and the machining errors is developed. Therefore, the error sources can be detected early and prevented during tool path planning. The analytical results indicate that the optimal tool orientation occurs when the curvature of the cutter's swept profile matches with the curvature of the local part surface. In addition, the optimal cutting direction generally follows the minimum curvature direction. Computer illustrations and example demonstrations are shown in this paper. The results reveal the developed method can accurately determine the optimal tool orientation and efficiently avoid machining errors for five-axis tool-end machining. [DOI: 10.1115/1.2035698]

This paper Fdeals with nonlinear plants subject to unknown parameters. A fuzzy model is first used to represent the plant. An equivalent switching plant model is then derived, which supports the design of a switching controller. It will be shown that the closed-loop system formed by the plant and the switching controller is a linear system. Hence, the system performance of the closed-loop system can be designed. An application example on controlling a two-inverted pendulum system on a cart will be given to illustrate the design procedure of the proposed switching controller. Index Terms--Nonlinear systems, switching controller, switching plant model, Takagi--Sugeno-Kang (TSK) fuzzy plant model.

The small-signal behavior of a frequency controlled resonant converter is modeled as an equivalent pulsewidth modulation (PWM) converter. By this model, a recently developed simulation algorithm for PWM converter is modified to simulate both the open-loop and closed-loop small-signal behavior. Experimental results show that this approach is accurate and efficient. Index Terms--Pulsewidth modulation (PWM) converters, resonant converters, simulation, smaU-signal analyses.

Gut 2003;52:1779-1783 Background and aims: Lamivudine induces favourable virological and biochemical responses but post-treatment relapses are frequent, even in patients with hepatitis B e antigen (HBeAg) loss or seroconversion. The [...]

We have constructed line-by-line fluorescence models for the ro-vibrational bands of the B-X system of sulfur dimers ([S.sub.2]). For the first time the detailed rotational lines of the bands are clearly resolved in the high-resolution echelle spectra of Comet Hyakutake (C/1996 B2), which were obtained at the Kitt Peak 4-m telescope on 26.4 March 1996 (UT). In order to construct satisfactory band models of the B--X system, we first compared the models to laboratory spectra available in literature, and then compared the models including Swings effects to the high-resolution spectra of Hyakutake. From the model fits, we derived a rotational temperature of 70 [+ or -] 10 K, which should represent a temperature of a coma region close to the nucleus, where most of the [S.sub.2] emissions originate. We present previously proposed scenarios for the origin of [S.sub.2] in cometary comae, and compare them with our spectral analysis. Keywords: Comet; Coma; Atmosphere; Molecule; Fluorescence; Radiative transfer

Presented is a study of fault equivalence in steady-state dc linear analog circuits. Equivalent fault relationships attributable to node isolation or equivalence in the driving-point and/or transfer characteristics of one-port network are shown to prevent effective fault diagnosis in a number of basic analog circuits. The analysis of these conditions using graph and transformation theorems is demonstrated to provide the basis for a more systematic approach to improving fault diagnosis. Index Terms--Equivalent faults, fault diagnosis of linear analog circuits, steady-state dc testing.

Research investigating the role played by modified atmosphere in maintaining the fresh qualities of cataloupe is presented. Particular attention is given to descriptions of experiments involving sealed film containers with different degrees of gas content.

A small signal simulation algorithm for converter circuits is developed. It is based on the sensitivity matrix used in the shooting method. The algorithm is efficient and is able to predict small signal response accurately at all frequencies. A modified version of the algorithm can also simulate the beat frequency effect when the frequency of the input excitation signal is close to half the switching frequency. Index Terms - PWM converters, simulation, small signal analyses.

The effect of dc flux on the core loss is examined for the practical range of power and frequency. Relevant core loss equations are derived and applied to an optimization algorithm to determine the minimum core loss at a given ratio of s (dc flux density to ac peak flux density). It has been found that the curves of hysteresis loss density versus the ratio of s exhibit a peak at a critical ratio. Below or above this critical ratio, the loss density decreases drastically. On the other hand, the curves of eddy-current loss density versus the ratio of s exhibits a minimum point at a critical ratio. Below or above this critical ratio, the loss density increases gradually. Index Terms - Influence of dc field intensity on the core loss, magnetic design.

Based on a single-stage isolated power-factor-corrected power supply (SSIPP or [S.sup.2][IP.sup.2]) employing a boost power-factor-correction (PFC) cell, the relationship between the input line voltage and line current of such switching regulators is studied. The conditions for unity power factor are derived. A control scheme to reduce the switch voltage stress while maintaining unity power factor is proposed. Practical implementation of the proposed control scheme is discussed. It is found that, by adding a simple input voltage feedforward to a conventional PWM controller, the switch voltage stress can be much reduced, while keeping the power factor very close to unity. Analysis and experimental results indicate that such a scheme is effective and feasible. Index Terms - Fast output-voltage regulation, power-factor correction, SSIPP.

By adding a suitable LC filter to the input of a Buck converter, it is possible to force the converter into discontinuous-input-voltage mode operation. A Buck converter in this mode of operation has useful properties such as power factor correction and soft turn-off switching. The operation, modeling, low-frequency behavior, and application of the converter are studied. Experimental results verifying the theoretical predictions are also presented. Index Terms - Buck converter in discontinuous-capacitor-voltage mode operation, Buck converter in discontinuous-input-voltage mode operation, discontinuous-capacitor-voltage mode operation of converters, discontinuous-input-voltage mode operation of converters, power factor correction using Buck converter, power factor correction using converters in discontinuous-capacitor-voltage mode operation, power factor correction using converters in discontinuous-input-voltage mode operation.

Cu/polyimide systems which are mutually inert showed a noticeable adhesion improvement after ion beam mixing. N(sub 2)(super +) ions were more effective in enhancing the adhesion strength than Ar+ because the N(sub 2)(super +) ions were incorporated as an active bond component. The adhesion improvement was determined to be caused by the induction of adhesion promoters on the polyimide by ion irradiation. A thin Al layer as a buffer layer produces a ternary compound of CuAl2O4 that improves the adhesion strength further.

Gaseous dilution on hydrogenated amorphous silicon nitride (a-SiNx:H) films produced changes in their physical, electrical and chemical properties. The dilution gases included were nitrogen, hydrogen, helium and argon, while silane and ammonia were used as reactive species. The addition of hydrogen and other gases produced a current density of 3 milliamperes per square centimeter. The Poole-Frenkel emission characterizes electronic conduction in these films. Field effect mobility is also affected by gaseous dilution.

A dominant deformation mechanism in an isostatic pressure sintering process of a powder compact is known as power law creep. The deformation of a pore was predicted from the existing stress analysis based on power law creep assuming a hollow sphere and a hollow cylinder. The deformation at high temperature (T > 0.4 Tm) involves both power law creep and diffusion enhanced by mechanical stress. The analysis performed by previous investigators included only the deformation caused by power law creep. The analysis in this paper is considering for both the deformation caused by power law creep and diffusion in the final stage of the HIP process for a hollow sphere and hollow cylinder models. The contribution of the diffusion mechanism to the total densification is investigated. The experimental results published for CoO are compared with the analytical result for power law creep only and for power law creep and diffusion. The results show that the effect of diffusion on the total densification is insignificant for densities of the order of 80percent of theoretical at low applied pressure, and for a small vacancy diffusion coefficient ([D.sub.upsilon]). However, the contribution of diffusion is increased in the high densification region ([rho] > 0.95), with high applied stress and high [D.sub.upsilon]. It is concluded that the diffusion mechanism enhances the densification and its rate in the final stage of HIP process.

The structural and the magnetic properties of polycrystalline [La.sub.1-x] [Sr.sub.x]Co[O.sub.3] (LSCO) have been studied experimentally. The single LSCO phase in all the prepared samples were confirmed by the X-ray diffraction and X-ray photoelectron spectroscopy measurements. From the temperature dependence of inverse magnetic susceptibility, the Curie temperatures are found to be 147 K, 217 K, and 232 K for x = 0.15, 0.25, and 0.3, respectively. However, zero-field-cooled magnetization measurement reveals a spin-glass-like behavior for x = 0.15. A neutron-diffraction study does not reveal the existence of an antiferromagnetic phase at low temperatures. It is thought that a more advanced magnetic model is required to elucidate the spin-glass behavior at low Sr concentrations. Index Terms--Cluster glass (CG), [La.sub.1-x] [Sr.sub.x] Co[O.sub.3] (LSCO), neutron diffraction.

The practical implementation of an efficient and accurate small-signal simulation algorithm is discussed. Examples are given to illustrate how converters with feedback or dependent switching should be modeled. A flowchart for the algorithm is also given to facilitate the programming. Index Terms--CAD, circuit simulation, converters, modeling, switching circuits.

The fabrication of the polymer-bonded composites of a Fe-Co based alloy and the characterization of their magnetic and mechanical properties is presented. Large compressive strength of 42 MPa is obtained for the composites, which indicates a solid bonding of flake-type powders by the polymer.

We report an unusual presentation of ganglioneuroblastoma with features of dilated cardiomyopathy in a 22 month old girl. She was admitted with cardiomegaly; during echocardiography a suspicious abdominal mass was [...]

A study is conducted to examine the microstructural and magnetic properties of amorphous, nanoclustered, and self-organized bilayer [Nd.sub.0.5][Sr.sub.0.5]Mn[O.sub.3] films fabricated by rf magnetron sputtering. The self-organized bilayer films with a homogeneous chemical composition and different microstructures demonstrated the magnetic properties typical for the interacting superparamagnetic (SPM) nanoparticles grown onto a continuous ferromagnetic (FM) layer.

A study analyzes the overall sensory quality of commercial broiler breast meat products marketed in the U.S. Results show that one air-chilled and one water-chilled/enhanced produced was most liked by the consumers and the greatest differences between products were texture differences.

The impact of long-term frozen storage on the tenderness, water-holding capacity and color of broiler breast fillets is determined. An increase in the storage period is shown to lead to a decrease in the moisture content, where as the thaw and cooking losses increases.

Two-step method and magnetron sputtering are used for preparing [Zn.sub.0.96][Mn.sub.0.04]O/ZnO coaxial nanocable and [Zn.sub.0.96][Mn.sub.0.04]O film. The magnetic property measurements have shown that these coaxial nanocables and films are ferromagnetic at room temperature and the saturated magnetization and the coercive field of the coaxial nanocable are larger than those of [Zn.sub.0.96][Mn.sub.0.04]O film.

An investigation to determine an energetically feasible method to reduce bean oligosaccharides for large-scale bean flour production is performed. Michigan black, red, and navy beans are treated by alpha-galactosidase, germination, or hydration to determine treatment effects on stachyose and raffinose levels.

Byline: Y.S. Lee, P.C. Brooks, D.C. Barton, D.A. Crolla This paper is the second in a series of three that together describe an integrated theoretical approach to the analysis of disc brake squeal. Within this paper, the specific problems of system linearisation and complex modal analysis are addressed. The likelihood of squeal noise occurrence is quantified by the definition of a single indicator derived from the system eigenvalues. Mode shape analysis permits study of the motion linked to each mode and a technique is presented that reconstructs a true picture of the complex mode through the combination of its real and imaginary components. Typical results are presented for stable and unstable modes of vibration which lead to the proposal of a mechanism that gives rise to the unstable squeal vibration.

Byline: Y.S. Lee, P.C. Brooks, D.C. Barton, D.A. Crolla This paper is the last in a series of three that present an integrated numerical approach to the analysis of disc brake squeal. It focuses on the application of the technique to the solution of a number of generic classes of problem encountered by the brake system engineer and the results are related to real world experience. The ability of the methodology to find direct use in such a broad area of application lies in the use of fully parameteriSed solid models to define the initial mechanical system. This flexibility is a powerful feature of the approach that ensures its continued use as a predictive tool. The paper concludes with a critical review of the technique and points to a number of refinement routes

Byline: Y.S. Lee, P.C. Brooks, D.C. Barton, D.A. Crolla This paper is the first in a series of three that describe an integrated approach to the analysis of disc brake squeal. The technique is based around the use of a parametric finite element representation of the disc-pad assembly. In this paper, the problem is introduced together with the philosophy that underpins the model. The procedure adopted to solve the non-linear contact problem, which occurs at the friction pair interface, is illustrated and typical results presented that show how the contact behaviour is influenced by change in interface friction levels, hydraulic actuation pressure and loading mechanism.

ESR and UV spectroscopic studies reveal that the action of alkali metals on dried zeolitic structures X and Y with Si/Al ratios of 1.1 and 2.4 yield ionic clusters. ESR spectrum of NaX with 13 equidistant linear and a hyperfine splitting constant a of 36.3G implies the presence of Na ions. NaY yields ionic clusters more easily than NaX for a given alkali metal due to a higher oxidation capacity which results from NaY's higher Si/Al ratio.