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Topic Review
Applications of Substrate-Integrated Waveguide
Substrate-integrated waveguide (SIW) is a modern day (21st century) transmission line that has recently been developed. This technology has introduced new possibilities to the design of efficient circuits and components operating in the radio frequency (RF) and microwave frequency spectrum. Microstrip components are very good for low frequency applications but are ineffective at extreme frequencies, and involve rigorous fabrication concessions in the implementation of RF, microwave, and millimeter-wave components. This is due to wavelengths being short at higher frequencies. Waveguide devices, on the other hand, are ideal for higher frequency systems, but are very costly, hard to fabricate, and challenging to integrate with planar components in the neighborhood. SIW connects the gap that existed between conventional air-filled rectangular waveguide and planar transmission line technologies including the microstrip.
  • 4.2K
  • 13 Apr 2022
Topic Review
Lymphatic Drainage of Renal Tissues
Acute kidney injury (AKI), especially if recurring, represents a risk factor for future chronic kidney disease. In intensive care units, increased intra-abdominal pressure is well-recognized as a significant contributor to AKI. Renal interstitial pressure changes synchronously to renal perfusion pressure. The renal parenchyma is primarily drained by the urine conducting and renal venous system. The renal lymphatic system can also contribute to renal compartment syndrome, the functional changes in the lymphatic flow was not investigated in connection with pneumo-peritoneum.
  • 4.2K
  • 17 May 2022
Topic Review
YOLOv5-AC
Attention Mechanism-Based Lightweight YOLOv5 for Track Pedestrian Detection. In response to the dangerous behavior of pedestrians roaming freely on unsupervised train tracks, the real-time detection of pedestrians is urgently required to ensure the safety of trains and people. Aiming to improve the low accuracy of railway pedestrian detection, the high missed-detection rate of target pedestrians, and the poor retention of non-redundant boxes, YOLOv5 is adopted as the baseline to improve the effectiveness of pedestrian detection by model pruning, improving attention mechanism, etc.
  • 4.2K
  • 15 Sep 2022
Topic Review
PCR and NGS in Acute Myeloid Leukemia
Acute myeloid leukemia (AML) is a clonal disorder that affects myeloid progenitor cells residing in the bone marrow (BM). This implies altered differentiation with subsequent abnormal proliferation and accumulation of inadequately matured myeloid cells. The detection of leukemic cells moved in the last two decades from immune-phenotyping to polymerase chain reaction (PCR) and real-time quantitative PCR (RT-qPCR). This technique was shown to be reproducible, accurate and highly sensitive for MRD monitoring, with a significant capacity in predicting prognosis, treatment effectiveness and relapse risk. NGS or massively parallel sequencing is a revolutionary method of DNA and RNA sequencing. It is called parallel because it sequences millions of DNA fragments simultaneously. In the early years of its appearance, Next Generation Sequencing (NGS) platforms were used primarily for cancer research purposes. Recently, they are increasingly emerging as irreplaceable diagnostic tools in clinical settings.
  • 4.2K
  • 10 Feb 2022
Topic Review
Biological Production of Vanillin
Vanillin (4-hydroxy-3-methoxybenzaldehyde), the primary ingredient in vanilla bean or pod extracts, possesses a rich, creamy, and distinctive vanilla smell, which is also one of the most significant aromas in the world. Vanillin can serve as a flavoring agent in the food industry (about 60%), a pharmaceutical intermediate in the pharmaceutical industry (about 7%), and a scent ingredient in the cosmetics sector (about 33%).
  • 4.2K
  • 08 May 2023
Topic Review
Mie–Gruneisen Equation of State
The Mie–Grüneisen equation of state is a relation between the pressure and the volume of a solid at a given temperature. It is used to determine the pressure in a shock-compressed solid. The Mie–Grüneisen relation is a special form of the Grüneisen model which describes the effect that changing the volume of a crystal lattice has on its vibrational properties. Several variations of the Mie–Grüneisen equation of state are in use. The Grüneisen model can be expressed in the form where V is the volume, p is the pressure, e is the internal energy, and Γ is the Grüneisen parameter which represents the thermal pressure from a set of vibrating atoms. If we assume that Γ is independent of p and e, we can integrate Grüneisen's model to get where p0 and e0 are the pressure and internal energy at a reference state usually assumed to be the state at which the temperature is 0K. In that case p0 and e0 are independent of temperature and the values of these quantities can be estimated from the Hugoniot equations. The Mie–Grüneisen equation of state is a special form of the above equation.
  • 4.2K
  • 22 Nov 2022
Topic Review
Development of Therapeutic Monoclonal Antibodies
We provide an overview of the challenges and advancements in the development of therapeutic monoclonal antibodies and antibody products.
  • 4.2K
  • 21 Sep 2021
Topic Review
Ultra-processed Foods
Ultra-processed foods were first defined by Dr. Carlos Monteiro in 2009 through the NOVA classification. Briefly, they are characterized in their formulation by the addition of cosmetic ingredients and/or additives for mainly industrial use - and having undergone an excessive processing  - to imitate, exacerbate, mask or restore sensory properties (aroma, texture, taste and color). It can also be very denaturing technological processes directly applied to the food (cooking-extrusion, puffing, etc.). They are food and drink products that have undergone specified types of food processing, usually by transnational and other very large 'Big food' corporations. These foods are designed to be 'convenient, eaten on the go, hyperpalatable and appealing to consumers, and, most importantly, the most profitable segment of Big Food companies’ portfolios because of these foods’ low-cost ingredients'. The NOVA-derived Siga score propose a complementary definition more focused ont the degradation of the food/ingredient matrix effect: "An ultra-processed food is characterized by the presence in its list of ingredients of at least one substance that is itself ultra-processed, called a marker of ultra-processing (MUP). These MUPs are obtained by synthesis, or by a succession of physical, chemical and/or biological processes applied to natural raw materials and which lead to a strong degradation compared to their original matrix".
  • 4.2K
  • 29 Oct 2020
Topic Review
Oral Hypoglycemic Agents
Diabetes mellitus (DM) is a chronic illness with an increasing global prevalence. More than 537 million cases of diabetes were reported worldwide in 2021, and the number is steadily increasing. The worldwide number of people suffering from DM is projected to reach 783 million in 2045. In 2021 alone, more than USD 966 billion was spent on the management of DM. Reduced physical activity due to urbanization is believed to be the major cause of the increase in the incidence of the disease, as it is associated with higher rates of obesity. Diabetes poses a risk for chronic complications such as nephropathy, angiopathy, neuropathy and retinopathy. Hence, the successful management of blood glucose is the cornerstone of DM therapy. The effective management of the hyperglycemia associated with type 2 diabetes includes physical exercise, diet and therapeutic interventions (insulin, biguanides, second generation sulfonylureas, glucagon-like peptide 1 agonists, dipeptidyl-peptidase 4 inhibitors, thiazolidinediones, amylin mimetics, meglitinides, α-glucosidase inhibitors, sodium-glucose cotransporter-2 inhibitors and bile acid sequestrants).
  • 4.2K
  • 15 Jun 2023
Topic Review
Large-Scale Piezoelectric-Based Aircraft Systems
A new approach in the development of aircraft and aerospace industry is geared toward increas-ing use of electric systems. An electromechanical (EM) piezoelectric-based system is one of the po-tential technologies that can produce a compactable system with a fast response and a high power density. However, piezoelectric materials generate a small strain, of around 0.1–0.2% of the original actuator length, limiting their potential in large-scale applications.
  • 4.2K
  • 20 Feb 2021
Topic Review
On Predictive Maintenance in Industry 4.0
In the era of the fourth industrial revolution, several concepts have arisen in parallel with this new revolution, such as predictive maintenance, which today plays a key role in sustainable manufacturing and production systems by introducing a digital version of machine maintenance. The data extracted from production processes have increased exponentially due to the proliferation of sensing technologies. Even if Maintenance 4.0 faces organizational, financial, or even data source and machine repair challenges, it remains a strong point for the companies that use it. Indeed, it allows for minimizing machine downtime and associated costs, maximizing the life cycle of the machine, and improving the quality and cadence of production.
  • 4.2K
  • 24 Aug 2022
Topic Review
Depersonalization Disorder
Depersonalization disorder (DPD), also known as depersonalization/derealization disorder (DPDR), is a mental disorder in which the person has persistent or recurrent feelings of depersonalization or derealization. Depersonalization is described as feeling disconnected or detached from one's self. Individuals experiencing depersonalization may report feeling as if they are an outside observer of their own thoughts or body, and often report feeling a loss of control over their thoughts or actions. In some cases, individuals may be unable to accept their reflection as their own, or they may have out-of-body experiences. Derealization is described as detachment from one's surroundings. Individuals experiencing derealization may report perceiving the world around them as foggy, dreamlike/surreal, or visually distorted. In addition to these depersonalization-derealization disorder symptoms, the inner turmoil created by the disorder can result in depression, self-harm, low self-esteem, phobias, panic attacks, and suicide. It can also cause a variety of physical symptoms, including chest pain, blurry vision, visual snow, nausea, and the sensation of pins and needles in one's arms or legs. Depersonalization-derealization disorder is thought to be caused largely by interpersonal trauma such as childhood abuse. Triggers may include significant stress, panic attacks, and drug use. Studies suggest a uniform syndrome for chronic depersonalization/derealization regardless of whether drugs or an anxiety disorder is the precipitant. It is unclear whether genetics plays a role; however, there are many neurochemical and hormonal changes in individuals with depersonalization disorder. The disorder is typically associated with cognitive disruptions in early perceptual and attentional processes. Diagnostic criteria for depersonalization-derealization disorder include persistent or recurrent feelings of detachment from one's mental or bodily processes or from one's surroundings. A diagnosis is made when the dissociation is persistent and interferes with the social or occupational functions of daily life. However, accurate descriptions of the symptoms are hard to provide due to the subjective nature of depersonalization and derealization and persons' ambiguous use of language when describing these episodes. In the DSM-5, it was combined with derealization disorder and renamed "depersonalization/derealization disorder" ("DDPD"). In the DSM-5, it remains classified as a dissociative disorder, while the ICD-10 calls it "depersonalization-derealization syndrome" and classifies it as a neurotic disorder. Although the disorder is an alteration in the subjective experience of reality, it is not a form of psychosis, as the person is able to distinguish between their own internal experiences and the objective reality of the outside world. During episodic and continuous depersonalization, the person can distinguish between reality and fantasy and the grasp on reality remains stable at all times. While depersonalization-derealization disorder was once considered rare, lifetime experiences with it occur in about 1–2% of the general population. The chronic form of the disorder has a reported prevalence of 0.8 to 1.9%. While brief episodes of depersonalization or derealization can be common in the general population, the disorder is only diagnosed when these symptoms cause substantial distress or impair social, occupational, or other important areas of functioning.
  • 4.2K
  • 23 Nov 2022
Topic Review
Biological Melatonin versus Synthetic Melatonin
Melatonin dietary supplements are widely consumed worldwide, with developed countries as the largest consumers, with an estimated annual growth rate of approximately 10% until 2027, mainly in developing countries. The wide use of melatonin against sleep disorders and particular problems, such as jet lag, has been added to other applications, such as anti-aging, anti-stress, immune system activation, anticancer, and others, which have triggered its use, normally without a prescription. The chemical industry currently covers 100% of the needs of the melatonin market.
  • 4.2K
  • 18 Apr 2023
Topic Review
Online Reviews
Online reviews, also referred to as electronic word of mouth (eWOM) or user-generated content (UGC), are all similar concepts with minor differences. eWOM is all electronic communications between producers and consumers and between consumers themselves: emails, websites, consumer review sites, blogs, virtual communities, chat rooms, newsgroups, and instant messaging. UGC is data generated online by consumers, e.g., text (consumer reviews and blogs) and picture data.
  • 4.2K
  • 09 Dec 2020
Topic Review
Bone Tissues
Osseous tissue is a kind of hard connective tissue, which is also composed of cells, fibers and matrix. The fibers are bone glue fibers (the same as collagen fibers), and the matrix contains a large amount of solid inorganic salts.
  • 4.2K
  • 13 Sep 2021
Topic Review
Constituents of a Free Radical UV Curing System
The essential constituents of a UV curing system are a resin, which is an oligomer whose backbone confers the properties to the final polymer; a monomer, which acts as a cross-linking agent and adjusts the viscosity of the mixture to an acceptable level for application; and a photoinitiator, which is responsible for the light absorbance and governs the curing depth and rate.
  • 4.2K
  • 21 Jul 2022
Topic Review
Zinc Complexes as Anticancer Agents
The search for anticancer metal-based drugs alternative to platinum derivatives could not exclude zinc derivatives due to the importance of this metal for the correct functioning of the human body. Zinc, the second most abundant trace element in the human body, is one of the most important micro-elements essential for human physiology. Its ubiquity in thousands of proteins and enzymes is related to its chemical features, in particular, its lack of redox activity and its ability to support different coordination geometries and to promote fast ligands exchange. Analogously to other trace elements, the impairment of its homeostasis can lead to various diseases and in some cases can be also related to cancer development. However, zinc complexes generally exert lower toxicity in comparison to other metal-based drugs and many zinc derivatives have been proposed as antitumor agents. Among them zinc complexes  comprising  N-donor ligands have been surveyed and analyzed. 
  • 4.2K
  • 22 Dec 2020
Topic Review
Walkable Cities
Reductions in walking trips have coincided with unprecedented levels of car trips, that caused several harmful environmental and health impacts. Walking is a simple, healthy and sustainable mode of transport that can be used for short urban trips or in combination with public transport for longer distances. The promotion of walkable cities encourages pedestrian activity, provides access to services and other businesses and satisfies daily needs without requiring to use a car.
  • 4.2K
  • 13 Sep 2022
Topic Review
Parity
In quantum mechanics, a parity transformation (also called parity inversion) is the flip in the sign of one spatial coordinate. In three dimensions, it can also refer to the simultaneous flip in the sign of all three spatial coordinates (a point reflection): It can also be thought of as a test for chirality of a physical phenomenon, in that a parity inversion transforms a phenomenon into its mirror image. All fundamental interactions of elementary particles, with the exception of the weak interaction, are symmetric under parity. The weak interaction is chiral and thus provides a means for probing chirality in physics. In interactions that are symmetric under parity, such as electromagnetism in atomic and molecular physics, parity serves as a powerful controlling principle underlying quantum transitions. A matrix representation of P (in any number of dimensions) has determinant equal to −1, and hence is distinct from a rotation, which has a determinant equal to 1. In a two-dimensional plane, a simultaneous flip of all coordinates in sign is not a parity transformation; it is the same as a 180° rotation. In quantum mechanics, wave functions that are unchanged by a parity transformation are described as even functions, while those that change sign under a parity transformation are odd functions.
  • 4.2K
  • 10 Nov 2022
Topic Review
Clear-channel station
A clear-channel station is an AM radio station in North America that has the highest protection from interference from other stations, particularly concerning night-time skywave propagation. The system exists to ensure the viability of cross-country or cross-continent radio service, and is enforced through a series of treaties and statutory laws. Now known as Class A stations since 1982, they are occasionally still referred to by their former classifications of Class I-A (the highest classification), Class I-B (the next highest class), or Class I-N (for stations in Alaska too far away to cause interference to the primary clear-channel stations in the lower 48 states). The term "clear-channel" is used most often in the context of North America and the Caribbean, where the concept originated. Since 1941, these stations have been required to maintain at least 10,000 watts of power to retain their status. Nearly all these stations in the United States , Canada and The Bahamas broadcast at 50,000 watts, with several clear-channel stations in Mexico going as high as 150,000 watts and XEW in Mexico City operating at 250,000 watts for over 80 years. (Cuba was originally included in the plan and had several stations given clear-channel status, but Cuba stopped participating after 1959.)
  • 4.2K
  • 08 Oct 2022
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