Improved complete ensemble empirical mode decomposition with adaptive noise: quasi-oppositional Jaya hybrid algorithm for ECG denoising

Electrocardiogram (ECG) is an effective, non-invasive, and economical diagnostic equipment, which plays a key role in screening and understanding of heart illnesses. However, the recorded signals are frequently distorted with several types of noises (baseline wander (BW), power-line interference (PLI), etc.) and the distortion creates serious challenges to healthcare providers. Therefore, it is imperative that the ECG signal should be noise-free and tidy as desirable to support correct decisions by physicians. In this paper, a novel hybrid methodology for ECG filtering is proposed, which comprises improved complete ensemble empirical mode decomposition with adaptive noise (ICEEMDAN) algorithm in conjunction with the quasi-oppositional Jaya algorithm (QOJA). The robust ICEEMDAN based decomposition approach is used to decompose the noisy ECG into several intrinsic mode functions (IMFs). Then, the frequency bands arising out of the combined BW and PLI are recognized prudently using the Fourier spectrum to evade any intersection with valuable information in the ECG signals. The QOJA is performed on noisy IMFs to suppress artifacts. The efficiency of our proposed hybrid methodology has been assessed by adding combined BW and PLI at a different signal-to-noise ratio (SNR) to ECG records from MIT/BIH arrhythmia database. The obtained SNR improvement (14.52–30.32 dB) discloses the superiority of the proposed hybrid methodology while comparing it with the ICEEMDAN joint with the least mean square (LMS) adaptive algorithm (11.58–28.21 dB) and ICEEMDAN (9.31–26.97 dB).

     

Formulation and development of orodispersible sustained release tablet of domperidone

Abstract

Commercially available domperidone orodispersible tablets (ODT) are intended for immediate release of the drug, but none of them have been formulated for sustained action. The aim of the present research work was to develop and evaluate orodispersible sustained release tablet (ODT-SR) of domperidone, which has the convenience of ODT and benefits of controlled release product combined in one. The technology comprised of developing sustained release microspheres (MS) of domperidone, followed by direct compression of MS along with suitable excipients to yield ODT-SR which rapidly disperses within 30?seconds and yet the dispersed MS maintain their integrity to have a sustained drug release. The particle size of the MS was optimized to be less than 200?μm to avoid the grittiness in the mouth. The DSC thermograms of MS showed the absence of drug-polymer interaction within the microparticles, while SEM confirmed their spherical shape and porous nature. Angle of repose, compressibility and Hausner’s ratio of the blend for compression showed good flowability and high percent compressibility. The optimized ODT-SR showed disintegration time of 21?seconds and matrix controlled drug release for 9?h. In-vivo pharmacokinetic studies in Wistar rats showed that the ODT-SR had a prolonged MRT of 11.16?h as compared 3.86?h of conventional tablet. The developed technology is easily scalable and holds potential for commercial exploitation.     

Optimization of hot melt extrusion parameters for sphericity and hardness of polymeric face-cut pellets

The aim of this study was to formulate face-cut, melt-extruded pellets, and to optimize hot melt process parameters to obtain maximized sphericity and hardness by utilizing Soluplus^® as a polymeric carrier and carbamazepine (CBZ) as a model drug. Thermal gravimetric analysis (TGA) was used to detect thermal stability of CBZ. The Box–Behnken design for response surface methodology was developed using three factors, processing temperature (?°C), feeding rate (%), and screw speed (rpm), which resulted in 17 experimental runs. The influence of these factors on pellet sphericity and mechanical characteristics was assessed and evaluated for each experimental run. Pellets with optimal sphericity and mechanical properties were chosen for further characterization. This included differential scanning calorimetry, drug release, hardness friability index (HFI), flowability, bulk density, tapped density, Carr’s index, and fourier transform infrared radiation (FTIR) spectroscopy. TGA data showed no drug degradation upon heating to 190?°C. Hot melt extrusion processing conditions were found to have a significant effect on the pellet shape and hardness profile. Pellets with maximum sphericity and hardness exhibited no crystalline peak after extrusion. The rate of drug release was affected mainly by pellet size, where smaller pellets released the drug faster. All optimized formulations were found to be of superior hardness and not friable. The flow properties of optimized pellets were excellent with high bulk and tapped density.     

Effects of Ion Advection and Thermal Convection on Pore Pressure Changes in High Permeable Chemically Active Shale Formations

Wellbore instability problems are often encountered while drilling in water active shales due to changes in pore pressure. The change in pore pressure is caused by hydraulic, thermal, chemical, and electrical potential gradients. In all previous studies it has been found that the effects of ion advection and thermal convection have a negligible effect on changes in pore pressure for a range of very low permeable shale formations (>10^?5 md). This is an appropriate assumption for very low permeable shale formations. For high permeable shale formations (e.g., shale with a disseminated microfissure network), however, thermal convection and ion advection can play a significant role. The authors present a hydro-chemo-thermo-electrical model based on finite element method to investigate the effect of advection on ion transfer and thermal convection on temperature and their combined effect on pore pressure in shale formations. All equations are based on the thermodynamics of irreversible processes in a discontinuous system. The characteristic Galerkin discretization method is used to stabilize the solution of advection and convection equations in the finite element approach. Results of this study revealed that ion and heat transfer are controlled primarily by permeability of the shale formations. Movement of fluid into or out of the formation is due to a combination of hydraulic, chemical, electrical, and thermal osmotic flow. Results have also shown that in high permeable shale formations the chemical potential gradient between the pore fluid and drilling fluid reaches equilibrium faster than in low permeable shale formations. This is mainly due to the advection of ion from drilling fluid to the shale formation.     

Optimal specifications for degrading characteristics

In this article, we show that the manufacturing target for a product characteristic affected by degradation is not the value that maximizes the quality of the product. By sacrificing some quality at the manufacturing stage it is possible to increase the product's lifetime and thus reduce the quality loss over a long period. We propose a procedure for finding the optimal manufacturing target that maximizes both quality and reliability of the product.     

Canarium zeylanicum seed oil: an edible oil with beneficial qualities

The quality parameters, fatty acid composition, phenolic compounds and antioxidant properties of the seed oil of Canarium zeylanicum were determined. The results indicate that the seed oil of Canarium zeylanicum is an excellent source of essential fatty acids which contains C18:2 (49.35 ± 0.35%) and C18:3 (19.09 ± 0.01%). The total phenol contents of the seed oil and the seed hull of Canarium zeylanicum were 66 ± 6 and 2014 ± 14 mg kg⁻¹respectively. The identified phenolic acids in the methanolic extracts of seed oil include 3,4-dihydroxybenzoic acid, p -hydroxybenzoic acid, vanillic acid and ellagic acid. Diphenyl-2-picrylhydrasyl radical scavenging activity, inhibition of deoxyribose degradation and the reducing power of the methanolic extracts of seed oil and seed hull of Canarium zeylanicum are comparable with those of butylated hydroxytoluene solutions.     

Space-filling designs for computer experiments: A review

ABSTRACT

Improving the quality of a product/process using a computer simulator is a much less expensive option than the real physical testing. However, simulation using computationally intensive computer models can be time consuming and, therefore, directly doing the optimization on the computer simulator can be infeasible. Experimental design and statistical modeling techniques can be used to overcome this problem. This article reviews experimental designs known as space-filling designs that are suitable for computer simulations. In the article, a special emphasis is given for a recently developed space-filling design called maximum projection design. Its advantages are illustrated using a simulation conducted for optimizing a milling process.     

Bayesian optimization of functional output in inverse problems

Optimization and Engineering - Motivated by the parameter identification problem of a reaction-diffusion transport model in a vapor phase infiltration processes, we propose a Bayesian optimization...     

Entropy analysis of muscular near-infrared spectroscopy (NIRS) signals during exercise programme of type 2 diabetic patients: Quantitative assessment of muscle metabolic pattern

Diabetes mellitus (DM) is a metabolic disorder that is widely rampant throughout the world population these days. The uncontrolled DM may lead to complications of eye, heart, kidney and nerves. The most common type of diabetes is the type 2 diabetes or insulin-resistant DM.     

Processing maps for hot-working of powder metallurgy 1100 Al-10 vol % SiC-particulate metal-matrix composite

The hot-working characteristics of the metal-matrix composite (MMC) Al-10 vol % SiC-particulate (SiC_p) powder metallurgy compacts in as-sintered and in hot-extruded conditions were studied using hot compression testing. On the basis of the stress-strain data as a function of temperature and strain rate, processing maps depicting the variation in the efficiency of power dissipation, given by = 2m/(m+1), where m is the strain rate sensitivity of flow stress, have been established and are interpreted on the basis of the dynamic materials model. The as-sintered MMC exhibited a domain of dynamic recrystallization (DRX) with a peak efficiency of about 30% at a temperature of about 500°C and a strain rate of 0.01 s^–1. At temperatures below 350°C and in the strain rate range 0.001–0.01 s^–1 the MMC exhibited dynamic recovery. The as-sintered MMC was extruded at 500°C using a ram speed of 3 mm s^–1 and an extrusion ratio of 101. A processing map was established on the extruded product, and this map showed that the DRX domain had shifted to lower temperature (450°C) and higher strain rate (1 s^–1). The optimum temperature and strain rate combination for powder metallurgy billet conditioning are 500°C and 0.01 s^–1, and the secondary metal-working on the extruded product may be done at a higher strain rate of 1 s^–1 and a lower temperature of 425°C.