Biomedical Engineering articles list

Two-phase flow in microfluidic-chip design of hydrodynamic filtration for cell particle sorting

As one of the flow-based passive sorting, the hydrodynamic filtration using a microfluidic-chip has shown to effectively separate into different sizes of subpopulations from cell or particle suspensions. Its model framework involving two-phase Newtonian or generalized Newtonian fluid (GNF) was developed, by performing the complete analysis of laminar flow and complicated networks of main and multiple branch channels. To predict rigorously what occurs in flow fields, we estimated pressure drop, velocity profile, and the ratio of the flow fraction at each branch point, in which the analytical model was validated with numerical flow simulations. As a model fluid of the GNF, polysaccharide solution based on Carreau type was examined. The objective parameters aiming practical channel design include the number of the branches and the length of narrow section of each branch for arbitrary conditions. The flow fraction and the number of branches are distinctly affected by the viscosity ratio between feed and side flows. As the side flow becomes more viscous, the flow fraction increases but the number of branches decreases, which enables a compact chip designed with fewer branches being operated under the same throughput. Hence, our rational design analysis indicates the significance of constitutive properties of each stream.

Myung-Suk Chun

Sorting of human mesenchymal stem cells by applying optimally designed microfluidic chip filtration

Human bone marrow-derived mesenchymal stem cells (hMSCs) consist of heterogeneous subpopulations with different multipotent properties: small and large cells with high and low multipotency, respectively. Accordingly, sorting out a target subpopulation from the others is very important to increase the effectiveness of cell-based therapy. We performed flow-based sorting of hMSCs by using optimally designed microfluidic chips based on the hydrodynamic filtration (HDF) principle. The chip was designed with the parameters rigorously determined by the complete analysis of laminar flow for flow fraction and complicated networks of main and multi-branched channels for hMSCs sorting into three subpopulations: small (<25>40 μm) cells. By focusing with a proper ratio between main and side flows, cells migrate toward the sidewall due to a virtual boundary of fluid layers and enter the branch channels. This opens the possibility of sorting stem cells rapidly without damage. Over 86% recovery was achieved for each population of cells with complete purity in small cells, but the sorting efficiency of cells is slightly lower than that of rigid model particles, due to the effect of cell deformation. Finally, we confirmed that our method could successfully fractionate the three subpopulations of hMSCs by analyzing the surface marker expressions of cells from each outlet.

Myung-Suk Chun

Efficient detection of escherichia coli o157:h7 using a reusable microfluidic chip embedded with antimicrobial peptide-labeled beads

The ability of antimicrobial peptides (AMPs) for effective binding to multiple target microbes has drawn lots of attention as an alternative to antibodies for detecting whole bacteria. We investigated pathogenic Escherichia coli (E. coli) detection by applying a microfluidic based biosensing device embedded with AMP-labeled beads. According to a new channel design, our device is reusable by the repeated operation of detection and regeneration modes, and the binding rate is more enhanced due to even distribution of the bacterial suspension inside the chamber by implementing influx side channels. We observed higher binding affinity of pathogenic E. coli O157:H7 for AMP-labeled beads than nonpathogenic E. coli DH5α, and the fluorescence intensity of pathogenic E. coli was about 3.4 times higher than the nonpathogenic one. The flow rate of bacterial suspension should be applied above a certain level for stronger binding and rapid detection by attaining a saturation level of detection within a short time of less than 20 min. A possible improvement in the limit of detection in the level of 10 cells per mL for E. coli O157:H7 implies that the AMP-labeled beads have high potential for the sensitive detection of pathogenic E. coli at an appropriate flow rate.

Myung-Suk Chun

Acoustic feedback cancellation in efficient hearing aids using genetic algorithm

Many people are distracted from the normal lifestyle, because of the hearing loss they have. Most of them do not use the hearing aids due to various discomforts in wearing them. The main and the foremost problem available in it is; the device introduces unpleasant whistling sounds, caused by the changing environmental noise, which is faced by the user daily. This paper describes the development of an algorithm, which focuses on the adaptive feedback cancellation, that improves the listening effort of the user. The genetic algorithm is one of the computational techniques, that is used in enhancing the above features. The performance can also be compared with other comprehensive analysis methods, to evaluate its standards.

Jayanthi G

Estimation of snr based adaptive-feedback equalizers for feedback control in hearing aids

Despite the evolution of modern technology, the users of hearing aids do not realize the persistence of feedback, while wearing the device until the condition becomes worse. The feedback cancellation algorithms, instead of cancelling the acoustic feedback, limits speech intelligibility. The paper presents a novel method for estimation of SNR based adaptive-feedback equalizers (SBAFE) algorithm to develop an optimized hearing aid for the feedback less sound transmission and achieving better speech discrimination. The data gathered for the optimization is visualized and compared with the traditional technology, which provides the subjective and objective quality of the hearing aids.

Jayanthi G

Early diagnosis model of alzheimer’s disease based on hybrid meta heuristic with regression based multi feed forward neural network

Alzheimer Disease is a chronic neurological brain disease. Early diagnosis of Alzheimer illness may the prevent the occurrence of memory cellular injury. Neuropsychological tests are commonly used to diagnose Alzheimer’s disease. The above technique, has a limited specificity and sensitivity. This article suggests solutions to this issue an early diagnosis model of Alzheimer’s disease based on a hybrid meta-heuristic with a multi-feed-forward neural network. The proposed Alzheimer’s disease detection model includes four major phases: pre-processing, feature extraction, feature selection and classification (disease detection). Initially, the collected raw data is pre-processed using the SPMN12 package of MATLAB. Then, from the pre-processed data, the statistical features (mean, median and standard deviation) and DWT are extracted. Then, from the extracted features, the optimal features are selected using the new Hybrid Sine cosine firefly (HSCAFA). This HSCAFA is a conceptual improvement of standard since cosine optimization and firefly optimization algorithm, respectively. Finally, the disease detection is accomplished via the new regression- based multi-faith neighbors’ network (MFNN). The final detected outcome is acquired from regression-based MFNN. The proposed methodology is performed on the PYTHON platform and the performances are evaluated by the matrices such as precision, recall, and accuracy.

Dr. Rajasekhar Butta

Potential role of hydrogel and its future applications in bioprinting and in-vitro organ development

Abstract: Recent studies on hydrogels have shown them as promising biomaterials for numerous applications involving tissue engineering, drug-screening, drug-delivery, and 3-D bioprinting because they show unique physicochemical properties. The ability of these structures to hold large amounts of water is because of their hydrophilic nature that provides a soft and hydrated environment like natural tissues. This makes them ideal for mimicking the extracellular matrix and supporting cell growth and proliferation. In tissue engineering, hydrogels might be used to create scaffolds that promote cell growth and facilitate tissue regeneration. Hydrogels can also be engineered in such a way that they intimate the mechanical and biochemical in vivo characteristics making them a versatile tool for applications in tissue engineering. Hydrogels are being used in drug screening, as they can be functionalized with different biochemicals in order to match the microenvironment of specific tissues. This allows researchers to study how drugs interact with cells and tissues in-vitro conditions, which can lead to more efficient strategies for drug development. For applications in drug delivery hydrogels are designed to release drugs in a sustainable and controlled way, improving the drug efficacy and reducing the toxicity of drugs. Designing can also be done in a way that they can target specific tissues and cells making them a promising tool for personalized medicine. Hydrogels are being used in 3-D bioprinting, where they serve as bio-inks that can be fabricated into complex structures with high precision. In comparison to conventional technologies, this is a promising technique that allows the construction of complex three-dimensional structures in a sequential manner by a computeraided system. One major challenge in bioprinting is finding such material that is suitable for printing and also satisfies the mechanical strength requisite for tissue engineering applications. That is where hydrogels serve as the most appropriate model and have encouraging or favorable operation potential as cell-affable materials. This technique has revolutionized tissue engineering by allowing researchers to create functional tissues and organoids and spheroids. Overall, hydrogel-based tissue engineering, drug screening, drug delivery, and 3D bioprinting are exciting areas of research with great potential to significantly impact different areas of medicine and biology.

Deepika Pal

Using a resnet50 with a kernel attention mechanism for rice disease diagnosis

The domestication of animals and cultivation of crops have been essential to human development throughout history, with the agricultural sector playing a pivotal role. Insufficient nutrition often leads to plant diseases, such as those affecting rice crops, resulting in yield losses of 20-40% of total production. These losses carry significant global economic consequences. Timely disease diagnosis is critical for implementing effective treatments and mitigating financial losses. However, despite technological advancements, rice disease diagnosis primarily depends on manual methods. In this study, we present a novel Self-Attention Network (SANET) based on the ResNet50 architecture, incorporating a kernel attention mechanism for accurate AI-assisted rice disease classification. We employ attention modules to extract contextual dependencies within images, focusing on essential features for disease identification. Using a publicly available rice disease dataset comprising four classes (three disease types and healthy leaves), we conducted cross-validated classification experiments to evaluate our proposed model. The results reveal that the attention-based mechanism effectively guides the Convolutional Neural Network (CNN) in learning valuable features, resulting in accurate image classification and reduced performance variation compared to state-of-the-art methods. Our SANET model achieved a test set accuracy of 98.71%, surpassing current leading models. These findings highlight the potential for widespread AI adoption in agricultural disease diagnosis and management, ultimately enhancing efficiency and effectiveness within the sector.

Mehdhar S. A. M. Al-Gaashani

Optimizing grid-connected photovoltaic (pv) battery energy storage through multi-objective ant-lion optimization (moalo)

As the demand for renewable energy continues to rise, it becomes crucial to discover effective ways to enhance grid-connected photovoltaic (PV) battery energy storage systems. The Institute of Petroleum Studies (IPS) complex at the University of Port Harcourt in Rivers State, Nigeria, embarked on a quest to determine the optimal approach for optimizing their PV battery energy storage system. This research aimed to fulfill this need by employing a diverse research methodology, incorporating the innovative MOALO theory. To begin with, the research gathered primary and secondary data to construct models for the power grid, solarPV, and battery. Furthermore, it meticulously analyzed the load profile of the IPS complex, at the University of Port Harcourt. Leveraging the power of the MOALO theory.The researchers accurately sized the system and evaluated the potential outcomes of simultaneously interconnecting all loads. To gauge the system's performance, there was a calculation of various parameters such as economics, random walk, boundary conditioning, entrapping ants, and ant trap development. Remarkably, the outcome showed that the fitness responses between the two trial runs, facilitated by the integration of MOALO, were strikingly similar, revealing a typical concaveconnected shape, which is characteristic of a multi-objective solver. The optimal multi-objective cost implication of the system was estimated to be around 4,300 USD, with a power mismatch performance of approximately -1.7819e+09. Based on these compelling findings, the study concluded that MOALO serves as an impressive optimization tool capable of minimizing power mismatches and optimizing costs. Moreover, it recommended the generation of excess power as a means to achieve sustainability.

FXintegrity Publishing

Classic and alternative disinfection practices for preventing of hospital-acquired infections: a systemic review

Ultraviolet (UV) disinfection technologies are well-known tools for microbial prevention in indoor public places which are frequently employed for disinfecting air, surfaces, and water. Such technologies have drawn a great deal of interest due to its potential application, especially in the domain of healthcare. This article discusses the shortcomings of chemical disinfectants and analyzes the current research standing on the development of various types of UV disinfection technologies for their prospective usage in the healthcare industry. Furthermore, the article provides a thorough analysis and in-depth evaluation of the current antibacterial studies using UV lamps and light-emitting diodes (LEDs) for the treatment of frequently encountered pathogens associated with healthcare. According to the systematic review, UV-LEDs have shown to be a potential source for delivering disinfection which is equally efficient or more effective than traditionally used UV lamps. The findings also provide valuable considerations for potentially substituting conventional lamps with LEDs that would be less expensive, more efficient, more robust, non-fragile and safer. With greater effectiveness and advantages, UV-LEDs have shown to be the potential UV source that could fundamentally be able to transform the disinfection industry. Therefore, the study supports the employment of UV-LED technology as a better and workable approach for effective disinfection applications. The study also offers insightful information that will help to direct future studies in the domain of hygienic practices used in healthcare facilities.

Jahanzeb

Two-stage rfid approach for localizing objects in smart homes based on gradient boosted decision trees with under- and over-sampling

eveloping automated systems with a reasonable cost for long-term care for elders is a promising research direction. Such smart systems are based on realizing activities of daily living (ADLs) to enable aging in place while preserving the quality of life of all inhabitants in smart homes. One of the research directions is based on localizing items used by elders to monitor their activities with fine-grained details of the progress. In this paper, we shed the light on this issue by presenting an approach for localizing items in smart homes. The presented method is based on applying machine learning algorithms to Radio Frequency IDentification (RFID) tags readings. Our approach achieves the required task through two stages. The first stage detects in which room the selected object is located. Then, the second one determines the exact position of the selected object inside the detected room. Additionally, we present an efficient approach based on gradient boosted decision trees for detecting the location of the selected object in a real-world smart home. Moreover, we employ some techniques of over- and under- sampling with data clustering for improving the performance of the presented techniques. Many experiments are conducted in this work to evaluate the performance of the presented approach for localizing objects in a real smart home. The results of the experiments have shown that our approach provides remarkable performance.

Shadi Abudalfa

Evaluation of the effects of thermal processing treatments on the nutrient and anti-nutrient composition of afzelia africana (akparata) flour

This research work aimed to evaluate the effects of thermal processing treatments on the nutrient anti-nutrient composition of Afzelia africana (Akparata) flour. The seeds were sorted, cleaned and processed into boiled, roasted and autoclaved lima bean flours. The flours obtained were analysed for proximate, vitamin and anti-nutrient contents using standard methods. The proximate composition of the samples revealed that the flours had a range of moisture, 8.23-12.40%, crude protein, 15.98-25.95%, fat, 21.00-28.21%, ash, 1.34-2.89%, crude fibre, 2.00-3.45%, carbohydrate, 38.68-49.33%, and energy 424.13 – 482.37kJ/100g, respectively. The vitamin contents of the flours showed that the samples contained 0.02±0.00 - 0.08±0.00mg/100g riboflavin, 0.78 - 1.98 mg/100g niacin, 0.40 - 0.89 mg/100g thiamine, 120.40-234.70mg/100g vitamin A, 72.11-134.19mg/100g ascorbic acid, 09.67-17.65mg/100g vitamin E, 310.60-430.60mg/100g B6, 3.47-5.87mg/100g B12, respectively. The result of the anti-nutrient composition of the flours also showed that the phytate, tannin, oxalate, cyanogenic glycosides, protease inhibitors, haemagglutinins inhibitors, levels of the samples were significantly (p<0.05) reduced by roasting and boiling treatments compared to the sample processed by autoclaving. In addition, the saponin content of the flours was relatively higher in boiled sample than in roasted and autoclaved flours. However, the nutrient and anti-nutrient contents of the flours observed that the flours have the potentials to be used as nutritional supplements in the preparation of a variety of food products than the raw sample.

OKECHUKWU OBED CHUKWUEMEKA

The silent scream of skin cells: a brief review of slow electrical signaling in the epithelium

Epithelial cells, lining the skin and internal organs, play a crucial role as protective barriers and regulators of substance transport. Traditionally, these cells were not considered to employ electrical signaling for communication. However, recent investigations have unveiled that epithelial cells generate slow electrical signals, termed the "silent scream," in response to injury, thus challenging conventional views of intercellular communication. A recent experimental investigation provided compelling evidence for this phenomenon, demonstrating the ability of these cells to transmit electrical signals over considerable distances within the epithelium. The research utilized microelectrode array chips to precisely detect subtle electrical events in keratinocytes and Madin-Darby Canine Kidney (MDCK) cells, revealing spiking activity characterized by slow propagation speeds, distinct from the rapid action potentials of neurons. The mechanisms underlying this novel signaling are explored, focusing on the involvement of mechanosensitive ion channels, calcium signaling, and Adenosine triphosphate (ATP) release. Calcium ions, well-established intracellular messengers, appear to play a central role in this biological phenomenon. Integrating this newly discovered communication mode into the existing understanding of skin cell biology reveals a more intricate picture of how skin senses and responds to its environment. The implications of this finding extend to various facets of skin physiology and pathology, including wound healing, inflammation, and skin aging. In wound healing, where endogenous electric fields guide cell migration and promote repair, this unique type of electrical signaling potentially plays a crucial part. Furthermore, aberrant electrical signaling might contribute to chronic inflammatory conditions, and age-related changes in this signaling could underlie the functional decline observed in aged skin. The potential for other environmental stressors to trigger the epithelial-generated electric signals also warrants investigation. The exploration concludes by discussing potential technological applications, such as bioelectric sensors and enhanced wound healing therapies, and future research directions aimed at further elucidating the molecular mechanisms and functional roles of this non-excitable cell electrophysiology.

Karishma

Starr–edwards ball caged mechanical heart valves’ reverberations – need for a phoenix of analysis with a critical mindset

The mechanical heart valve prosthesis with a caged ball has been around for 60 years. It has since experienced changes and adjustments. The Starr–Edwards (SE) valve was a pioneer and was taken out of clinical use in the late 2000s. SE is reportedly close to or has reached the age of 50, according to numerous sources from around the globe. The author’s observations and review of the literature about thrombogenicity, pannus formation, left ventricular outflow tract obstructions, and infective endocarditis in the SE valves, which were reportedly higher before its clinical ending, were only an overestimation and were not supported by scientific data. However, it was less discussed in the article, along with potential benefits. The main reasons for its demise were its obtrusive size and unattractive shape. There have been several successful implantations of these valves in Asian nations and reports of fewer primary failures and unexpected cardiac fatalities. Therefore, there is a need for extensive data gathering, documentation, and more recent studies on these valves to prepare for a prospective revival of use with newer research, mainly when long-term durability is considered.

Karishma