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Topic Review
Non-Invasive Micro-Test Technology
Non-invasive micro-test technology (NMT) is a scientific research technology used for measuring physiological events of intact biological samples. NMT is used for research in many biological areas such as gene function, plant physiology, biomedical research, and environmental science. Most living things experience a constant exchange of ions and molecules with their surroundings as a result of biological processes. NMT uses specialized flux sensors, derived from microelectrodes, to measure this dynamic ion/molecule activity called flux around an intact sample. These fluxes reveal information about physiological phenomena. Each NMT flux sensor is selective or specific for a particular ion/molecule of choice. Some of the more commonly published ion/molecule flux sensors are those that are commercially available, such as Ca2+, H+, K+, Na+, Cl−, Mg2+, Cd2+, NH4+, NO3−, Pb2+, Cu2+, O2, H2O2, and IAA (indole-3-acetic acid). Some other flux sensors include glutamate, glucose, Zn2+, Hg2+, and more that have been designed by individual laboratories. NMT measures how much, how fast, and in what direction the chosen ions/molecules are moving. This is defined as diffusion flux, which is the amount of substance per unit area per unit time. The principle of how NMT measures flux was described in the 1990s by a few different laboratories; Lionel Jaffe at the Marine Biological Laboratory described the Vibrating Probe technique, and Ian Newman at the University of Tasmania described the MIFE™ technique. There are also technologies SERIS and SIET that use this principle.
  • 1.5K
  • 18 Oct 2022
Topic Review
Microfluidic Systems and Breast Cancer Metastasis
Microfluidic devices are useful tools in studying biological phenomena involving fluid flow, thin tissue culture, and cell mobility; each of these aspects make microfluidic techniques attractive for studying human breast cancer, which is the most commonly occurring cancer in women and the second most common cancer overall worldwide.
  • 1.5K
  • 15 Feb 2022
Topic Review
Low-Cost Thermal Cameras
Thermal imaging is a promising technology in the medical field, in which infrared (IR) sensors can be used in e-health applications. However, in order to make this technology more accessible, the suitability of low-cost devices for such applications has been evaluated. Low-cost sensors present reduced capabilities compared to more expensive high-end devices. Therefore, their characterization is of outmost interest, which is performed in terms of the following parameters: non-uniformity (NU) effects and correction as well as their dependence on room temperature, noise-equivalent temperature difference (NETD), and response curve stability with temperature. In this work, a good performance is shown for the selected low-cost sensor, especially when used in temperature-controlled environments. Thus, the suitability of such sensors for medical applications is confirmed, proving its efficiency for the particular application we are focused on, this is, the assessment of diabetic foot ulcers.
  • 1.5K
  • 29 Oct 2020
Topic Review
Electrochemical Signal Amplification in Olfactory and Taste Evaluation
Biosensors are powerful analytical tools used to identify and detect target molecules. Electrochemical biosensors, which combine biosensing with electrochemical analysis techniques, are efficient analytical instruments that translate concentration signals into electrical signals, enabling the quantitative and qualitative analysis of target molecules. Electrochemical biosensors have been widely used in various fields of detection and analysis due to their high sensitivity, superior selectivity, quick reaction time, and inexpensive cost. However, the signal changes caused by interactions between a biological probe and a target molecule are very weak and difficult to capture directly by using detection instruments. Therefore, various signal amplification strategies have been proposed and developed to increase the accuracy and sensitivity of detection systems. 
  • 1.5K
  • 19 Aug 2022
Topic Review
Photodynamic Therapy
Photodynamic therapy (PDT) is a promising therapeutic strategy for cancers where surgery and radiotherapy cannot be effective. PDT relies on the photoactivation of photosensitizers, most of the time by lasers to produced reactive oxygen species and notably singlet oxygen. The major drawback of this strategy is the weak light penetration in the tissues. To overcome this issue, recent studies proposed to generate visible light in situ with radioactive isotopes emitting charged particles able to produce Cerenkov radiation. In vitro and preclinical results are appealing, but the existence of a true, lethal phototherapeutic effect is still controversial.
  • 1.5K
  • 15 Dec 2020
Topic Review
Foot/Ankle Prostheses Design Approach
There are different alternatives when selecting removable prostheses for below the knee amputated patients. The designs of these prostheses vary according to their different functions. These prostheses designs can be classified into Energy Storing and Return (ESAR), Controlled Energy Storing and Return (CESR), active, and hybrid. This paper aims to identify the state of the art related to the design of these prostheses of which ESAR prostheses are grouped into five types, and active and CESR are categorized into four groups. Regarding patent analysis, 324 were analyzed over the last six years.
  • 1.5K
  • 29 Jun 2021
Topic Review
Surface Plasmon Resonance-Based Biosensors for Advanced Bioprocess Monitoring
Biomanufacturers are being incited by regulatory agencies to transition from a quality by testing framework, where they extensively test their product after their production, to more of a quality by design or even quality by control framework. This requires powerful analytical tools and sensors enabling measurements of key process variables and/or product quality attributes during production, preferably in an online manner. As such, the demand for monitoring technologies is rapidly growing. In this context, researchers believe surface plasmon resonance (SPR)-based biosensors can play a role in enabling the development of improved bioprocess monitoring and control strategies.
  • 1.5K
  • 22 Dec 2021
Topic Review
Antimicrobial Properties of Lignocellulosic Materials
Pathogenic microbes are a major source of health and environmental problems, mostly due to their easy proliferation on most surfaces. Currently, new classes of antimicrobial agents are under development to prevent microbial adhesion and biofilm formation. However, they are mostly from synthetic origin and present several disadvantages. The use of natural biopolymers such as cellulose, hemicellulose, and lignin, derived from lignocellulosic materials as antimicrobial agents has a promising potential. Lignocellulosic materials are one of the most abundant natural materials from renewable sources, and they present attractive characteristics, such as low density and biodegradability, are low-cost, high availability, and environmentally friendly.
  • 1.5K
  • 08 Apr 2021
Topic Review
Photoplethysmography for the Assessment of Arterial Stiffness
There is growth in assessing arterial stiffness using photoplethysmography (PPG) and propose PPG as a potential tool for assessing vascular ageing in the future. Blood vessels deteriorate with age, losing elasticity and forming deposits. This raises the likelihood of developing cardiovascular disease (CVD), widely reported as the global leading cause of death. The ageing process induces structural modifications in the vascular system, such as increased arterial stiffness, which can cause various volumetric, mechanical, and haemodynamic alterations. Numerous techniques have been investigated to assess arterial stiffness, some of which are currently used in commercial medical devices and some, such as PPG, of which still remain in the research space.
  • 1.5K
  • 26 Dec 2023
Topic Review
LED-Based Photoacoustic System
Photoacoustics, being a noninvasive and functional modality, has the potential for small-animal imaging. However, the conventional photoacoustic tomographic systems use pulsed lasers, making it expensive, bulky, and require long acquisition time. We have developed a photoacoustic and ultrasound tomographic imaging system with LEDs as the light source and acoustic detection using a linear transducer array. We have demonstrated full-view tomographic imaging of a mouse.
  • 1.5K
  • 29 Apr 2021
Topic Review
Physical and Chemical Modification for Hemodialysis Membranes
Despite significant research efforts, hemodialysis patients have poor survival rates and low quality of life. Ultrafiltration (UF) membranes are the core of hemodialysis treatment, acting as a barrier for metabolic waste removal and supplying vital nutrients. So, developing a durable and suitable membrane that may be employed for therapeutic purposes is crucial. Surface modificationis a useful solution to boostmembrane characteristics like roughness, charge neutrality, wettability, hemocompatibility, and functionality, which are important in dialysis efficiency. The modification techniques can be classified as follows: (i) physical modification techniques (thermal treatment, polishing and grinding, blending, and coating), (ii) chemical modification (chemical methods, ozone treatment, ultraviolet-induced grafting, plasma treatment, high energy radiation, and enzymatic treatment); and (iii) combination methods (physicochemical). Despite the fact that each strategy has its own set of benefits and drawbacks, all of these methods yielded noteworthy outcomes, even if quantifying the enhanced performance is difficult. A hemodialysis membrane with outstanding hydrophilicity and hemocompatibility can be achieved by employing the right surface modification and immobilization technique. Modified membranes pave the way for more advancement in hemodialysis membrane hemocompatibility.
  • 1.5K
  • 09 Nov 2022
Topic Review
Cr-free High-Temperature Water-Gas Shift Catalysts
Replacement of toxic Cr in the industrial Fe-oxide based High-Temperature Water-Gas Shift (HT-WGS) catalysts has been the focus of intense research in the past decades. In the current manuscript, we examine the promotion effect of Ca, Ni, Co and Ge as possible Cr substituents, and Ca and Ni are found to improve catalysts performance relative to Cr promotion. The current study, besides finding two promising Cr substitutes (Ca and Ni) for the HT-WGS reaction catalyst, also emphasizes on the qualities a promoter must possess to become a suitable substitution of Cr. The remarkable performance of Ca and Ni promoters are related to their ability to stabilize the surface area of the respective catalysts by making partial or complete solid solution with the bulk Fe-oxide phase and by promoting highly redox Cu0-FeOx interfacial sites on the catalyst surface. The poorer performance exhibited by Co and Ge promoters is related to the lack of their ability to promote the highly active Cu0-FeOx interfacial sites along with inability of Co to stabilize the surface area. All the promoters follow a redox type mechanism for the HT-WGS reaction.
  • 1.5K
  • 09 Nov 2020
Topic Review
Magnetic Polymers for Microfluidic Sorting
Magnetophoresis offers many advantages for manipulating magnetic targets in microsystems. The integration of micro-flux concentrators and micro-magnets allows achieving large field gradients and therefore large reachable magnetic forces. However, the associated fabrication techniques are often complex and costly, and besides, they put specific constraints on the geometries. Magnetic composite polymers provide a promising alternative in terms of simplicity and fabrication costs, and they open new perspectives for the microstructuring, design, and integration of magnetic functions.
  • 1.5K
  • 30 Jul 2021
Topic Review
LAMP-Based Point-of-Care Biosensors for Rapid Pathogen Detection
Seeking optimized infectious pathogen detection tools is of primary importance to lessen the spread of infections, allowing prompt medical attention for the infected. Among nucleic-acid-based sensing techniques, loop-mediated isothermal amplification (LAMP) is a promising method, as it provides rapid, sensitive, and specific detection of microbial and viral pathogens and has enormous potential to transform current point-of-care molecular diagnostics.
  • 1.5K
  • 01 Dec 2022
Topic Review
Algae-Based Biofuels
Microalgal biomass has gained a significant role in the development of dif-ferent high-end (nutraceuticals, colorants, food supplements, and pharmaceuticals) and low-end products (biodiesel, bioethanol, and biogas) due to its rapid growth and high carbon-fixing effi-ciency. Therefore, microalgae are considered a useful and sustainable resource to attain energy security while reducing our current reliance on fossil fuels. From the technologies available for obtaining biofuels using microalgae biomass, thermochemical processes (pyrolysis, Hydrothermal Liquefaction (HTL), gasification) have proven to be processed with higher viability, because they use all biomass. However, due to the complex structure of the biomass (lipids, carbohydrates, and proteins), the obtained biofuels from direct thermochemical conversion have large amounts of heteroatoms (oxygen, nitrogen, and sulfur). As a solution, catalyst-based processes have emerged as a sustainable solution for the increase in biocrude production. 
  • 1.5K
  • 11 Jan 2021
Topic Review
Micro-Computed Tomography
Micro-computed tomography (micro-CT) is a consolidated imaging technology allowing non-destructive three-dimensional (3D) qualitative and quantitative analysis by the observation of microstructures with high resolution. This paper Ten Years of Micro-CT in Dentistry and Maxillofacial Surgery: A Literature Overview aims at delivering a structured overview of literature about studies performed using micro-CT in dentistry and maxillofacial surgery (MFS) by analyzing the entire set of articles to portray the state of the art of the last ten years of scientific publications on the topic. 
  • 1.5K
  • 23 Feb 2021
Topic Review
Capacitive Field-Effect Bio-Chemical Sensors
       Electrolyte-insulator-semiconductor (EIS) field-effect sensors belong to a new generation of electronic chips for biochemical sensing, enabling a direct electronic readout. The review gives an overview on recent advances and current trends in the research and development of chemical sensors and biosensors based on the capacitive field-effect EIS structure—the simplest field-effect device, which represents a biochemically sensitive capacitor. Fundamental concepts, physicochemical phenomena underlying the transduction mechanism and application of capacitive EIS sensors for the detection of pH, ion concentrations, and enzymatic reactions, as well as the label-free detection of charged molecules (nucleic acids, proteins, and polyelectrolytes) and nanoparticles, are presented and discussed.
  • 1.5K
  • 19 Apr 2022
Topic Review
Electroencephalography
Electroencephalography (EEG) is a noninvasive, safe, and relatively convenient technique to record brain activities, which allows quantitative methods to detect changes and patterns of EEG signals related to DOC. The best feature of EEG data is neural oscillations. From the perspective of biophysics, EEGs are extracellular currents that reflect the total dendritic postsynaptic potentials in millions of parallel pyramidal cells.
  • 1.5K
  • 20 Oct 2021
Topic Review
Implant
An implant is a medical device manufactured to replace a missing biological structure, support a damaged biological structure, or enhance an existing biological structure. Medical implants are man-made devices, in contrast to a transplant, which is a transplanted biomedical tissue. The surface of implants that contact the body might be made of a biomedical material such as titanium, silicone, or apatite depending on what is the most functional. In some cases implants contain electronics, e.g. artificial pacemaker and cochlear implants. Some implants are bioactive, such as subcutaneous drug delivery devices in the form of implantable pills or drug-eluting stents.
  • 1.5K
  • 25 Oct 2022
Topic Review
Brain Stroke Monitoring
Stroke is a medical disease that affects millions of people worldwide per year, which leads to permanent disabilities or even death. It occurs when the regular flow of rich-oxygen blood through a brain vessel is interrupted due to a clot or a burst of it, triggering the death of brain cells and requiring prompt diagnosis and intervention after its onset to improve the prognosis significantly. The two main types of stroke are hemorrhagic and ischemic ones.
  • 1.4K
  • 27 Oct 2020
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