A perfectly matched layer (PML) absorbing material composed of a uniaxial anisotropic material is presented for the truncation of finite-difference time-domain (FDTD) lattices It is shown that the uniaxial PML material formulation is mathematically equivalent to the perfectly matched layer method published by Berenger (see J Computat Phys, Oct 1994) However, unlike Berenger's technique, the uniaxial PML absorbing medium presented in this paper is based on a Maxwellian formulation Numerical examples demonstrate that the FDTD implementation of the uniaxial PML medium is stable, equal in effectiveness as compared to Berenger's PML medium, while being more computationally efficient

An anisotropic perfectly matched layer-absorbing medium for the truncation of FDTD lattices

Background
Kangaroo mother care (KMC), originally defined as skin-to-skin contact between a mother and her newborn, frequent and exclusive or nearly exclusive breastfeeding, and early discharge from hospital, has been proposed as an alternative to conventional neonatal care for low birthweight (LBW) infants.

Objectives
To determine whether evidence is available to support the use of KMC in LBW infants as an alternative to conventional neonatal care before or after the initial period of stabilization with conventional care, and to assess beneficial and adverse effects.

Search methods
We used the standard search strategy of the Cochrane Neonatal Review Group. This included searches in CENTRAL (Cochrane Central Register of Controlled Trials; 2016, Issue 6), MEDLINE, Embase, CINAHL (Cumulative Index to Nursing and Allied Health Literature), LILACS (Latin American and Caribbean Health Science Information database), and POPLINE (Population Information Online) databases (all from inception to June 30, 2016), as well as the WHO (World Health Organization) Trial Registration Data Set (up to June 30, 2016). In addition, we searched the web page of the Kangaroo Foundation, conference and symposia proceedings on KMC, and Google Scholar.

Selection criteria
Randomized controlled trials comparing KMC versus conventional neonatal care, or early-onset KMC versus late-onset KMC, in LBW infants.

Data collection and analysis
Data collection and analysis were performed according to the methods of the Cochrane Neonatal Review Group.

Main results
Twenty-one studies, including 3042 infants, fulfilled inclusion criteria. Nineteen studies evaluated KMC in LBW infants after stabilization, one evaluated KMC in LBW infants before stabilization, and one compared early-onset KMC with late-onset KMC in relatively stable LBW infants. Sixteen studies evaluated intermittent KMC, and five evaluated continuous KMC.

KMC versus conventional neonatal care: At discharge or 40 to 41 weeks' postmenstrual age, KMC was associated with a statistically significant reduction in the risk of mortality (risk ratio [RR] 0.60, 95% confidence interval [CI] 0.39 to 0.92; eight trials, 1736 infants), nosocomial infection/sepsis (RR 0.35, 95% CI 0.22 to 0.54; five trials, 1239 infants), and hypothermia (RR 0.28, 95% CI 0.16 to 0.49; nine trials, 989 infants; moderate-quality evidence). At latest follow-up, KMC was associated with a significantly decreased risk of mortality (RR 0.67, 95% CI 0.48 to 0.95; 12 trials, 2293 infants; moderate-quality evidence) and severe infection/sepsis (RR 0.50, 95% CI 0.36 to 0.69; eight trials, 1463 infants; moderate-quality evidence). Moreover, KMC was found to increase weight gain (mean difference [MD] 4.1 g/d, 95% CI 2.3 to 5.9; 11 trials, 1198 infants; moderate-quality evidence), length gain (MD 0.21 cm/week, 95% CI 0.03 to 0.38; three trials, 377 infants) and head circumference gain (MD 0.14 cm/week, 95% CI 0.06 to 0.22; four trials, 495 infants) at latest follow-up, exclusive breastfeeding at discharge or 40 to 41 weeks' postmenstrual age (RR 1.16, 95% CI 1.07 to 1.25; six studies, 1453 mothers) and at one to three months' follow-up (RR 1.20, 95% CI 1.01 to 1.43; five studies, 600 mothers), any (exclusive or partial) breastfeeding at discharge or at 40 to 41 weeks' postmenstrual age (RR 1.20, 95% CI 1.07 to 1.34; 10 studies, 1696 mothers; moderate-quality evidence) and at one to three months' follow-up (RR 1.17, 95% CI 1.05 to 1.31; nine studies, 1394 mothers; low-quality evidence), and some measures of mother-infant attachment and home environment. No statistically significant differences were found between KMC infants and controls in Griffith quotients for psychomotor development at 12 months’ corrected age (low-quality evidence). Sensitivity analysis suggested that inclusion of studies with high risk of bias did not affect the general direction of findings nor the size of the treatment effect for main outcomes.

Early-onset KMC versus late-onset KMC in relatively stable infants: One trial compared early-onset continuous KMC (within 24 hours post birth) versus late-onset continuous KMC (after 24 hours post birth) in 73 relatively stable LBW infants. Investigators reported no significant differences between the two study groups in mortality, morbidity, severe infection, hypothermia, breastfeeding, and nutritional indicators. Early-onset KMC was associated with a statistically significant reduction in length of hospital stay (MD 0.9 days, 95% CI 0.6 to 1.2).

Authors' conclusions
Evidence from this updated review supports the use of KMC in LBW infants as an alternative to conventional neonatal care, mainly in resource-limited settings. Further information is required concerning the effectiveness and safety of early-onset continuous KMC in unstabilized or relatively stabilized LBW infants, as well as long-term neurodevelopmental outcomes and costs of care.

/pdf/kangaroo-mother-care-to-reduce-morbidity-and-mortality-in-omlxanqs0r.pdf

Kangaroo mother care to reduce morbidity and mortality in low birthweight infants

A compact representation is given of the electric- and magnetic-type dyadic Green's functions for plane-stratified, multilayered, uniaxial media based on the transmission-line network analog along the aids normal to the stratification. Furthermore, mixed-potential integral equations are derived within the framework of this transmission-line formalism for arbitrarily shaped, conducting or penetrable objects embedded in the multilayered medium. The development emphasizes laterally unbounded environments, but an extension to the case of a medium enclosed by a rectangular shield is also included.

/pdf/multilayered-media-green-s-functions-in-integral-equation-icv3t901yt.pdf

Multilayered media Green's functions in integral equation formulations

The biometric person authentication technique based on the pattern of the human iris is well suited to be applied to any access control system requiring a high level of security. This paper examines a new iris recognition system that implements (i) gradient decomposed Hough transform / integro-differential operators combination for iris localization and (ii) the "analytic image" concept (2D Hilbert transform) to extract pertinent information from iris texture. All these image-processing algorithms have been validated on noised real iris images database. The proposed innovative technique is computationally effective as well as reliable in terms of recognition rates.

/pdf/person-identification-technique-using-human-iris-recognition-4joa3juirv.pdf

Person Identification Technique Using Human Iris Recognition

An overview is given over some of the most widely used numerical techniques for solving the electromagnetic scattering problem that start from rigorous electromagnetic theory. In particular, the theoretical foundations of the separation of variables method, the finite-difference time-domain method, the finite-element method, the method of lines, the point matching method, the method of moments, the discrete dipole approximation, and the null-field method (or extended boundary condition method) are reviewed, and the advantages and disadvantages of the different methods are discussed. Aspects concerning the T matrix formulation and the surface Green's function formulation of the electromagnetic scattering problem are addressed.

Numerical methods in electromagnetic scattering theory

A direct three-dimensional finite-difference time-domain (FDTD) method is applied to the full-wave analysis of various microstrip structures. The method is shown to be an efficient tool for modeling complicated microstrip circuit components and microstrip antennas. From the time-domain results the input impedance of a line-fed rectangular patch antenna and the frequency-dependent scattering parameters of a low-pass filter and a branch-line coupler are calculated. These circuits were fabricated and the measurements made on them are compared with the FDTD results and shown to be in good agreement. >

Application of the three-dimensional finite-difference time-domain method to the analysis of planar microstrip circuits

A method for the calculation of the current distribution, resistance, and inductance matrices for a system of coupled superconducting transmission lines having finite rectangular cross-section is presented. These calculations allow accurate characterization of both high-T/sub c/ and low-T/sub c/ superconducting strip transmission lines. For a single stripline geometry with finite ground planes, the current distribution, resistance, inductance, and kinetic inductance are calculated as functions of the penetration depth for various film thicknesses. These calculations are then used to determine the penetration depth for Nb, NbN, and YBa/sub 2/Cu/sub 3/O/sub 7-x/ superconducting thin films from the measured temperature dependence of the resonant frequency of a stripline resonator. The calculations are also used to convert measured temperature dependence of the quality factor to the intrinsic surface resistance as a function of temperature for an Nb stripline resonator. >

Current distribution, resistance, and inductance for superconducting strip transmission lines

A report is presented on measurements of the surface impedance, Z/sub S/, of YBa/sub 2/Cu/sub 3/O/sub 7-x/ thin films using a stripline resonator. The films were deposited on LaAlO/sub 3/ substrates by off-axis magnetron sputtering. The authors obtained Z/sub S/ as a function of frequency from 1.5 to 20 GHz, as a function of temperature from 4 K to the transition temperature ( approximately 90 K), and as a function of the RF magnetic field from zero to 300 Oe. At low temperatures the surface resistance, R/sub S/, of the films shows a very weak dependence on the magnetic field up to 225 to 250 Oe. At 77 K, R/sub S/ is proportional to the square of the field. The penetration depth shows a much weaker dependence on the field than does R/sub S/. The origins of the magnetic field dependence of Z/sub S/ are also discussed. >

Stripline resonator measurements of Z/sub s/ versus H/sub rf/ in YBa/sub 2/Cu/sub 3/O/sub 7-x/ thin films

A rigorous analysis of the resonance frequency problem of both the cylindrical-rectangular and the wraparound microstrip structure is presented. The problem is formulated in terms of a set of vector integral equations. Using Galerkin's method to solve the integral equations, the complex resonance frequencies are studied with sinusoidal basis functions which incorporate the edge singularity. The complex resonance frequencies are computed using a perturbation approach. Modes suitable for resonator or antenna applications are investigated. The edge singularity of the patch current is shown to have no significant effect on the accuracy of the results. It is shown that the HE/sub 10/ modes of the cylindrical-rectangular and wraparound patches are more appropriate for resonator applications. The HE/sub 01/ and TE/sub 01/ modes of the cylindrical-rectangular and wraparound patches, respectively, are efficient radiating modes. >

Resonance in cylindrical-rectangular and wraparound microstrip structures

Extended-spectrum beta-lactamases (ESBLs) are bacterial enzymes that confer resistance to advanced generation cephalosporins and can lead to therapeutic failures. There has been no analysis of factors associated with the risk of acquisition of ESBLs in neonates in an intensive care unit from northern India. The CTX-M ESBL enzymes impart resistance against advanced generation cephalosporins (e.g. cefotaxime) and CTX-M variants have become the most prevalent ESBLs worldwide. The CTX-M-15 enzyme in particular is increasingly being reported from Escherichia coli isolates from northern India together with TEM-1. Moreover, E. coli is the most common cause of neonatal sepsis. Accordingly, this study aimed to: (i) characterize the mode of transmission of bla(CTX-M) and bla(TEM) among ESBL-producing E. coli strains isolated from patients admitted to a neonatal intensive care unit (NICU), and (ii) identify factors associated with the acquisition of the said strains in male and female neonates. A total of 97 ESBL-producers was identified among 266 E. coli strains isolated from 238 neonates. The isolates were screened for bla(CTX-M), bla(TEM), armA, rmtA and rmtB, the last three genes being responsible for aminoglycoside resistance. PCR amplified bla(CTX-M) genes were cloned and sequenced. Five bla(CTX-M-15), two rmtB, two bla(TEM-1) and thirteen class1 integrons were detected. All the bla(CTX-M-15) positive isolates, except one, were clonally related. Both univariate and multivariate analyses of factors for the acquisition of the said strains were performed with respect to the sex of the neonates. 'Length of stay in the NICU' was found to be the single independent factor associated with ESBL acquisition. In conclusion, our data suggest that male neonates who are colonized or infected by ESBL-producing E. coli have a longer stay in the NICU compared to their female counterparts. This prolonged stay may be due to male neonates becoming colonized/infected earlier than their female counterparts. Plasmid-mediated-conjugal transfer was found to be the mechanism of transfer of the bla(CTX-M-15) resistance marker in the described setting.

Acquisition of extended-spectrum β-lactamase producing Escherichia coli strains in male and female infants admitted to a neonatal intensive care unit: molecular epidemiology and analysis of risk factors

S.M. Ali

Papers

Application of the three-dimensional finite-difference time-domain method to the analysis of planar microstrip circuits

Current distribution, resistance, and inductance for superconducting strip transmission lines

Stripline resonator measurements of Z/sub s/ versus H/sub rf/ in YBa/sub 2/Cu/sub 3/O/sub 7-x/ thin films

Resonance in cylindrical-rectangular and wraparound microstrip structures

Acquisition of extended-spectrum β-lactamase producing Escherichia coli strains in male and female infants admitted to a neonatal intensive care unit: molecular epidemiology and analysis of risk factors