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Computerised prescriptions for Hospital Discharge Orders (HDO) are used world-wide to secure medication processes.To evaluate physicians' adoption of computerised provider order-entry (CPOE) for HDO and the prescribing error rate of HDO in an acute medical care unit.A prospective study was conducted in an internal medicine department over a six-month period. The use rate of CPOE for HDO edition, prescription lines concordance between CPOE-edited HDO, exit prescriptions transcribed in the discharge summary (DS), and prescribing error rate in CPOE-edited HDO were all evaluated.A total of 407 patients with HDO were included in the study. HDO were edited via CPOE system for 350 patients (86%), among which 124 (35%) were identically transcribed, 217 (62%) had discrepancies, and nine (3%) were not transcribed in the discharge summary (DS). Prescription errors were analysed using the total of 2,854 drugs prescribed on HDO. Although hospital pharmacists had signalled discrepancies and provided recommendations to the prescribers via alerting pharmaceutical interventions in CPOE 67 prescription errors (error rate of 2.3%) were found. Errors included 53 cases of refractory period disrespected, four cases of drug interactions, three cases of drug redundancies, and two cases of excessive dosage.This study highlights that most HDO were edited via the CPOE system. Together with pharmacist's interventions, the CPOE system contributed to reducing the prescription error rate in HDO. However, discrepancies in the recording process to DS were frequent, calling for reinforcement of error prevention strategies upon the integration of a CPOE system in the hospital's Electronic Health Records. Providing regular training for physicians is also a requirement.

RATIONALE & OBJECTIVE: The KDIGO (Kidney Disease: Improving Global Outcomes) guideline on CKD presented an international classification system that ranks patients' risk for CKD progression. Few data on children informed guideline development STUDY DESIGN: Observational cohort study SETTINGS AND PARTICIPANTS: Children aged 1-18 years enrolled in the North American Chronic Kidney Disease in Children (CKiD) cohort study and the European Effect of Strict Blood Pressure Control and ACE Inhibition on the Progression of CRF in Pediatric Patients (ESCAPE) trial. PREDICTOR: Level of estimated glomerular filtration rate (eGFR) and proteinuria (urine protein-creatinine ratio (mg/mg)) at study entry OUTCOME: A composite event of renal replacement therapy, 50% reduction of estimated GFR (eGFR), or eGFR 2.0 at study entry. Six ordered stages with varying combinations of eGFR categories (60-89, 45-59, 30-44 and 15-29 ml/min/1.73m(2)) and UPCR categories (2.0) described the risk continuum. Median times to event ranged from >10 years for eGFR 45-90 and UPCR 2. Children with glomerular disease were estimated to have a 43% shorter time to event than children with nonglomerular disease. Cross-validation demonstrated risk patterns that were consistent across the ten subsample validation models. LIMITATIONS: Observational study, utilized cross validation rather than external validation CONCLUSION: CKD staged by level of eGFR and proteinuria characterizes the timeline of progression and can guide management strategies in children.

Consider the discrete wavelet transform (DWT) of a time series X={Xt,t ∈ Z} with weakly stationary K th differences. Such time series are encountered in many situations, including unit root or long memory processes. If the wavelet has at least K vanishing moments, the DWT is jointly stationary across scales provided that small scales coefficients are reshaped in appropriate blocks to cope with the downsampling embedded in the DWT. Our goal is to compute the covariance matrix or the joint spectral density of the DWT, given the autocovariance of the Kth differences. We assume that the DWT corresponds to a multiresolution analysis (MRA), which allows us to compute wavelet coefficients iteratively through a succession of finite impulse response (FIR) filters and downsampling. This iterative scheme, however, is not suitable for our purpose in the case where the process X itself is not stationary. Hence, we first derive an iterative algorithm with the same DWT output but with input the Kth differences of the time series. An iterative low complexity scheme is then deduced to compute the exact covariance matrix and spectral density of the DWT. This new algorithm is an opportunity to investigate how using exact DWT covariance computations improves previously proposed statistical methods that rely on approximated computations. Numerical experiments are used for comparisons. Two cases are examined: 1) a local semi-parametric likelihood estimation of long memory processes in the wavelet domain and 2) the computation of a test statistic for detecting change points in the wavelet domain for long memory processes. A real data set analysis is also presented. Namely, economic structural changes are investigated by looking for change points in the daily S&P 500 absolute log returns.

Resume L'endotheline 1 (ET-1) possede une puissante action vasoconstrictrice, en particulier au niveau renal. Cette etude decrit la mise au point d'un dosage de l'ET-1 a partir de reactifs commerciaux sur un volume de plasma reduit (0,6 ml) et evalue chez l'enfant l'influence de l'insuffisance renale sur les concentrations plasmatiques de l'ET-1. L'ET-1 est prealablement extraite sur minicolonnes Sep Pack C18 activees par du methanol, equilibrees par de l'eau distillee, eluees par un melange acide trifluoroacetique, acetonitrile, eau (v/v/v). Les rendements d'extraction sont de 90,5 ± 8,9%. Le dosage radio-immunologique utilise un standard ET-1 Novabiochem et un immunserum anti-ET-1 Peninsula. Les coefficients de variation intra- et interessais sont respectivement de 10,7 et 15,8%. Chez les enfants insuffisants renaux non dialyses, les concentrations plasmatiques d'ET-1 (9,8 ± 3,2 pg/ml; moyenne ± DS; n =48) sont plus elevees ( P n = 29) et inversement correlees ( P n = 41; P

Missing value estimation is important in DNA microarray data analysis. A number of algorithms have been developed to solve this problem, but they have several limitations. Most existing algorithms are not able to deal with the situation where a particular time point (column) of the data is missing entirely. In this paper, we present an autoregressive-model-based missing value estimation method (ARLSimpute) that takes into account the dynamic property of microarray temporal data and the local similarity structures in the data. ARLSimpute is especially effective for the situation where a particular time point contains many missing values or where the entire time point is missing. Experiment results suggest that our proposed algorithm is an accurate missing value estimator in comparison with other imputation methods on simulated as well as real microarray time series datasets.

It is well-known (Narula et al., 1998) that the performance of a multiple input single output (MISO) communication system can be improved if channel information is used. In this work we exploit both temporal and spacial correlation of the fading channel to design the best precoder in sense of minimum mean-square error. This performance of the precoder is compared using an EM- like decoding, a PSP decoding and a new proposed decoding algorithm.

In this paper we consider the localization of a mobile station (MS) in time division multiple access (TDMA) based communication systems. We use joint angle and delay measurements of the emitted signals, impinging on an antenna array at different base stations (BSs). Contrary to previously reported work, our technique takes into account not only the measurement noise, but also multipath propagation and possible BSs reporting only non line of sight (NLOS) measurements. Data are processed using the maximum likelihood (ML) approach based on an implementation of the Expectation Maximization (EM) algorithm. We illustrate the proposed approach using simulated data.

The article deals with a technique of voice forgery using the ALISP (automatic language independent speech processing) approach. Such a technique allows the voice of an arbitrary person (the impostor) to be transformed, forging the identity of another person (the client). Our goal is to demonstrate that an automatic speaker recognition system could be seriously threatened by a transformation of this kind. For this purpose, we use a speaker verification system to calculate the likelihood that the forged voice belongs to the genuine client. Experiments on NIST 2004 evaluation data show that the equal error rate for the verification task is significantly increased by our voice transformation.

In this paper, we consider the localization of a source from quantized measurements of time of arrivals (TOA) or time difference of arrivals (TDOA). Applications include, as particular examples, acoustic source localization from a network of microphones under communication constraints, and the localization of a base station using a geolocalized mobile station using timing advance measurements. We use a maximum likelihood approach, based on an efficient implementation of the EM algorithm. Contrary to previously reported work, our technique takes into account not only the measurement noise, but also the presence of outliers (for example, non line of sight propagation) and the quantization. We illustrate our findings using simulated data and real field measurements.

Orthogonal frequency division multiplex (ODFM) is an attractive way of transmitting signals, by turning a wide-band signal into several narrow band ones. Orthogonal transmultiplexers are the basic tools required for emitting these signals and recovering them at the receiver side. It is well known that the only DFT modulated transmultiplexers are based on a rectangular window as a prototype, if one sticks to critically sampled systems. This paper investigates the possibilities brought by using oversampled FIR transmultiplexers instead of the critically sampled ones.

In a MPEG-4 analytic audio scene, spatialization filters can be used after an audio coder. When properly tuned, a MPEG advanced audio coder (AAC), generates an inaudible distortion if a sufficient output bit-rate is available, and, more important in the context of our study, as long as the listener has direct access to the unprocessed output of the decoder. We show that using a spatialization filter after the decoder, as described in the MPEG-4 standard, may damage the perceived quality. We propose solutions and present a modified encoder working with a hearing model that includes all audio processing (including spatialization), which allows bit-rate reduction without quality damage.

A new class of blind equalization cost functions have been proposed (see. Shtrom, V. and Fan, H., IEEE Trans. on SP., vol.46, no.10, p.2674-83, 1998). They have the particularity of being unimodal, and some of them are sectionally convex in the combined system domain (CDS). Both properties seem very attractive for a cost function, though no proof (or specific definition) was given of the sectional convexity. We show, using a particular case of this class, that sectional convexity not only implies fixing a delay, but that it also requires to fix the value of the coefficient associated with such delay. We show that the CMA (constant modulus algorithm) criterion shares the same property, and that this property is difficult to maintain in actual algorithms.

This paper presents two ways of obtaining more robust and/or efficient blind equalization algorithms. The first one is based on the linear combination of second order statistics methods (SOS) and higher order statistics methods (HOS) in such way that the advantages of both approaches are kept. The new algorithm has better performance than each of its constituents taken separately (pure HOS or SOS method) rather than performance "in between". The second idea consists of taking into account some deterministic knowledge of the input signal in the SOS methods. The results obtained show that this technique also enhances the performance of the algorithm.

The authors deal with frequency-domain (FD) adaptive identification with application to acoustic echo cancellation. Several proposed frequency-domain LMS algorithms are reviewed and unified in the common framework of fast convolution using the short-term Fourier transform. A more flexible identification scheme is then proposed, making it possible to independently control the delay and the adaptation rate. The theoretical proof of convergence of this new scheme is provided together with simulations demonstrating the efficiency of this method in both stationary and nonstationary environments. >

Objectifs La stenose des arteres renales est systematiquement recherchee en cas d’hypertension arterielle (HTA) de novo chez l’enfant. L’echo-Doppler est l’examen realise de premiere intention, mais sa sensibilite est faible. L’arteriographie est actuellement l’examen de reference. Cet examen est invasif et comporte une morbidite non negligeable. Le but de ce travail est d’evaluer l’interet du scanner multicoupe de derniere generation dans le diagnostic et l’exploration des stenoses de l’artere renale chez l’enfant. Materiels et methodes Sept enfants hospitalises pour bilan d’HTA de novo ont beneficie d’un angioscanner des arteres renales. Les resultats d’imagerie ont pu etre correles a l’angiographie numerisee ou aux donnees chirurgicales. Resultats Dans tous les cas, le scanner a confirme la presence d’une stenose des arteres renales uni ou bilaterale, a pu en evaluer l’etendue, l’importance et la localisation en vue d’un eventuel geste interventionnel radiologique ou chirurgical. Il permet egalement de faire le bilan d’autres anomalies arterielles associees et de realiser si besoin une cartographie vasculaire pre-operatoire. Conclusion Le scanner multicoupe de derniere generation est l’examen de choix dans l’exploration des stenoses de l’artere renale chez l’enfant pour en faire le diagnostic et guider la conduite therapeutique

Results of receiver performance for the detection of a coherent light signal in the presence of background radiation are obtained and compared for two different types of background noise: a Gaussian field and a Gaussian field whose complex analytic signal is not circularly symmetric. It is pointed out that the randomness in the noise radiation does not significantly diminish the probability of correct detection.

Quantum communication is studied under the cutoff-rate criterion for transmission of M coherent states of real amplitude (M=2, . . ., 7). Comparison with other measurement operators of interest, such as the number and the quasi-classical operators, is made. The effect of quantization of the decision level on the cutoff rate is considered. >

Results on the efficient capacity of a noisy PPM photon-counting channel are presented. Optimization of the optical system over the number of slots, the average power of the signal and the frequency bandwidth of the channel is considered and studied. The regions of quantum-limited operations and weak background noise are analysed in detail.

The cutoff rate R/sub 0/ of an optical channel transmitting M-ary phase-shift-keyed coherent states is calculated for a receiver using the optimum quantum detector. This is shown to be nearly equivalent, when M>>1, to a system that measures the phase of the received signal. A closed-form expression yielding a good approximation to R/sub 0/ is derived. >

Cut-off rate performance for phase modulated coherent states in a noiseless optical channel, using a phase measurement operator is calculated. The results obtained deviate significantly from those given by the upper bound, shown previously to be close to the optimal in several practical cases.

Numerical computation of the capacity of binary optical channel using photon-counting techniques have been performed. The results obtained show that the so-called two-photon coherent source (TCS) provides a better transmission of the optical information than ideal laser as already demonstrated by Yuen and Shapiro and also by Helstrom from the probability of error point of view. On the other hand rather than using capacity as the criterion, the R cut-off rate is taken as the practical measure of communication performance of the channel. This cut-off rate is calculated in different cases and for soft and hard decisions. A method of calculation to bound R is developed from the relationship between the channel reliability rate function and the probability generating function. This simple method is thus utilized to compare the performance of the channel with TCS and those obtained with ideal laser.

In the course of chronic renal failure, aluminium may deposit and accumulate in different tissues. The aluminium content of parathyroid glands was measured in 31 haemodialysis patients at the time of a parathyroidectomy. The values were compared with those obtained from ten control patients with primary hyperparathyroidism without renal failure, and were related to bone remodelling. Of the 31 patients, 27 had a bone biopsy after double tetracycline labelling, at the time of parathyroidectomy. Twenty-one patients had severe hyperparathyroidism, three patients had hyperparathyroidism associated with osteomalacia, three patients had mild hyperparathyroidism with reduced bone formation. Seven patients had bone aluminium deposits, associated with osteomalacia in one case. The parathyroid aluminium was 62 +/- 35.7 (mumol/g glandular dry weight) in haemodialysis patients and 14.3 +/- 6.3 in control patients (P less than 0.001). A significant positive correlation existed between parathyroid aluminium and serum aluminium (P less than 0.01). The parathyroid aluminium was not different in the patients with and without bone aluminium deposits. A weak correlation was found between parathyroid aluminium and plasma parathyroid hormone. A significant negative correlation existed between parathyroid aluminium and osteoblastic surfaces (P less than 0.05), but no correlation was found with bone formation rate at tissue and bone multicellular units levels. We conclude that aluminium accumulates in parathyroid glands of dialysed patients. Severe hyperparathyroidism may coexist with aluminium overload of parathyroid glands. A marked aluminium overload, however, may cut short the course of hyperparathyroidism and may decrease parathyroid function and cellular activity in bone.