Biomedical Engineering: Applications, Basis and Communications

In recent years, the strategy of using microspheres as drug carrier system has been very much considered. Also the use of natural polymers for pharmaceutical applications is very attractive. Given that various polymer materials are available for making microspheres, there is an active research to develop new, safe and effective release for microspheres. Olibanum is used as a drug carrier in this study. Also dexamethasone (DEX) is one of the commonly bioactive molecules used in bone tissue engineering. In this research, the purification and characterization of olibanum were first studied by FTIR, XRD, pH determination and MTT test. Due to its non-toxicity, biocompatibility, availability and biodegradability, this material can be a good choice as a natural polymer. Then the microspheres were synthesized with single emulsion method and studied by SEM and FTIR. The morphology and structure of the microspheres revealed that they are spherical and separate, which have rough and porous surface. Also the release mechanism of drug from olibanum microspheres was determined in accordance with the different kinetic drug release models. Investigating the drugs release behavior and degradation rate of microspheres revealed that they were suitable for dexamethasone-controlled release and can be used well in tissue engineering scaffolds.

Finger deformities are a major concern among the Indian population, where the increase of risk factors are higher for people suffering from Rheumatoid Arthritis. The deformities hinder the movements in the finger, affecting their day to day activities. Finger splint is a device which is used to support and correct this deformity in order to improve function. Three-dimensional modeling and 3D printing techniques are the standard measures used. The proposed methodology involves 3D modeling which was done using Solidworks 2013, along with standard measurements taken from the patients with deformities due to Rheumatoid Arthritis. The measurements were obtained using a vernier caliper. The 3D printing was done using Fused Deposition Modeling (FDM) and the materials needed for the same are Acrylonitrile Butadiene Styrene (ABS) and flex Polylactic Acid (PLA). The 3D printer used for the same is Flashforge Dreamer 3D printer. The volunteers were fitted with the custom finger splint. The finger splint is light-weight, easy to maintain and clean, with an inventive design based on the finger deformity. It is comfortable and helps support the patients during daily activities. It serves as an easy slip-on. Since it is well-ventilated, swelling of the finger does not occur. Future research will focus on the correction of the deformity, in addition to the biomechanical aspect of finger deformities.

The field of nanofluidics research has spanned over the past decade with a variety of promising applications. We investigate the “laminar boundary layer flow” of a Newtonian nanofluid past a moving extendable/contractable horizontal plate with surface velocity and thermal slip effects. The passively controlled nanofluid model (PCM) is considered. Such models are physically more realistic as compared to the “actively controlled models” (ACM). Using Lie symmetry group method, the governing equations are reduced by a set of highly coupled nonlinear ODE’s with thermo-solutal coupled boundary conditions. The reduced equations are solved numerically by a generalized collocation method. The influences of the emerging parameters on the local skin friction factor and the local Nusselt number are depicted numerically. The skin friction is decreased as the thermophoresis and buoyancy ratio parameters are decreased. The heat transfer rates reduce with thermophoresis and buoyancy ratio parameters. Velocity slip also leads to a rise in wall temperature gradient. This study is relevant to near-wall flows in nanofluid fuel cells, nano-materials processing, etc.

The main goal of this event-related potentials (ERPs) study was to assess the effects of stimulations in Stroop task in brain activities of patients with different degrees of depression. Eighteen patients (10 males, with the mean age $34.43\pm 13.14$) were asked to fill out Beck’s depression questionnaire. Electroencephalographic (EEG) signals of subjects were recorded in three channels (Pz, Cz, and Fz) during Stroop test. This test entailed 360 stimulations, which included 120 congruent, 120 incongruent, and 120 neutral stimulations. To analyze the data, 18 time features in each type of stimulus were extracted from the ERP components and the optimal features were selected. The correlation between the subjects’ scores in Beck’s depression questionnaires and the extracted time features in each recording channel was calculated in order to select the best features. Total area, and peak-to-peak time window in the Cz channel in both the congruent and incongruent stimulus showed significant correlation with Beck scores, with $r=0.5984$, $p=0.008$ and $r=0.5890$, $p=0.01$, respectively. Consequently, given the correlation between time features and the subjects’ Beck scores with different degrees of depression, it can be interpreted that in case of growth in degrees of depression, stimulations involving congruent images would produce more challenging interferences for the patients compared to incongruent stimulations which can be more effective in diagnosing the level of disorder.

The main focus of this paper is to solve the nonlinear and non-stationary problems in electroencephalographic (EEG) signals, which has been solved by the proposed method by using convolutional neural networks (CNN) as the classifiers and assembling Local Mean Decomposition (LMD) and cepstral coefficients as the feature extraction methods to achieve epileptic seizure detection with signal analysis and processing. In this proposed method, LMD and cepstral coefficients have been employed to solve the nonlinear and non-stationary problems in feature extraction and infusion, and then, the feature can be employed to feed to the recognition engine named CNN, and finally, the epileptic seizure detection can be achieved by this step. Publicly available EEG database from the University of Bonn (UoB), Germany had been used to verify the effectiveness and robustness of this proposed method on feature extraction. The complete dataset of total 7960 EEG segments, three recognition problems marked as AB versus CD versus E, the average classification accuracy of these segments can be generally obtained as highly as 99.84%, the maximal classification accuracy is 99.87%, and the lowest recognition accuracy is 98.74%. To the best of our knowledge, the excellent performance of the proposed method has shown that this method can be employed to track the patient’s healthy state and monitor the moment of epilepsy seizure.

Diabetes mellitus is a metabolic disorder that affects the production or usage of insulin by the body. Diabetes prevails in the body as a long-term condition which causes several other disorders if left unnoticed. Proper control of Diabetes needs continuous monitoring. The current measurement technique is invasive in nature and requires the withdrawal of blood from the body. Periodic quantification of blood glucose leads to pain and discomfort for the subject. This paper presents a non-invasive glucose measuring system using near-infrared diffuse reflectance spectroscopy (DRS). This work attempts to determine the blood glucose value from the diffuse reflected spectra in the NIR region. The study is executed with the spectral signatures of 33 diabetic subjects collected non-invasively using diffuse reflectance spectrometer from a diabetic centre. Blood glucose level of the same subjects are also recorded using the clinical method. The spectral information is subjected to standard normal variate (SNV) preprocessing method to remove baseline drift and then dimension reduction using singular value decomposition (SVD) is applied to the preprocessed data. The extracted singular values when compared with the clinically measured blood glucose is found to have a proportional relationship. The proposed study using singular value decomposition paves us the way for estimating the blood glucose value non-invasively with the obtained set of clinical blood glucose and the corresponding singular value table as a standard reference set.

This study examined the biocompatibility of blood vessels and a biodegradable drug-loaded vascular stent. The Traditional Chinese Medicine System Laboratory of Chung Yuan Christian University prepared the vascular stent, and our study verified the sustained release of drugs from the stent when it was within blood vessels. A platelet adhesion experiment revealed that stents with less surface roughness resulted in a reduction in the number of adhered platelets and decreased fibrinogen accumulation. The results of a hemolysis experiment verified that the hemolysis index was between 1% and 1.4%, within the range of no hemolysis and would not cause hypoxia. Subsequently, a drug release rate experiment indicated that the amount of released everolimus increased with time. The greatest amount of drug that was released occurred at 8h, with a release rate of 36.95%. A swelling rate experiment revealed that the degree of swelling of the hyaluronic acid (HA) that contained everolimus was 10 times less than that of the original HA; therefore, the use of a material with a low swelling rate in vascular stents did not immediately cause an obstruction in blood vessels. A lactate dehydrogenase (LDH) toxicity experiment revealed that the percentage of LDH released was 13–18%. This indicated that the cell viability was not affected and that there was no cytotoxicity; thus, the stent was suitable for use in blood vessels. This study proved that the prepared biodegradable drug-loaded vascular stent had favorable blood compatibility, no cytotoxicity, and a suitable drug release rate. Moreover, the drug release material was made from a material with a low degree of swelling. As a result of our findings, this new type of stent is suitable for application in blood vessels.

The intervertebral disc (IVD) is a three-dimensional, biphasic structure containing fluid and solid skeleton; fluid may flow through pores of solid tissues and bones that plays an important pumping role in the support of the solid skeleton and for further nutrition transportation in the IVD. Swelling pressure (SP) is mainly caused by the fluid motion and the straining of the solid skeleton in the biphasic structure that affects stress levels generated in the medium and may possibly cause the tissue rupture. In aging or herniated IVDs, radial tears on the tissue structure is always found; however, relevance between such tears and the mechanical stresses is still uncertain. Experimental inspection for the previous problems is still unable to reach. Therefore, the poroelastic finite element study on such subject is encouraged for the understanding of pathological problems occurred in the spine. To revise the related formulations, an intensive process beginning with the biphasic equilibrium is introduced that derives solid–fluid interactive equations on the SP and various stresses under exclusive domains. A contingent poroelastic finite element model of the IVD is also introduced. The SP in the annular fibrosis closed to the periphery of radial tears is disturbed that makes further variation of geometry and stress levels in the IVD; the load-bearing function of the structure is thus changed. The simulating procedures proposed in the study are significant for further studies on the IVD and biological tissues and bones.