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Topic Review
Uric Acid Oxidant/Antioxidant Paradox
Extracellular uric acid (UA) exhibits antioxidant properties by effectively scavenging free radicals in human plasma, but this benefit might be disturbed by the hydrophobic lipid layer of the cell membrane. In contrast, intracellular free oxygen radicals are produced during UA degradation, and superoxide is further enhanced by interacting with NADPH oxidase. This intracellular oxidative stress, together with inflammatory cytokines induced by UA, stimulates osteoclast bone resorption and inhibits osteoblast bone formation. UA also inhibits vitamin D production and thereby results in hyper-parathyroidism, which causes less UA excretion in the intestines and renal proximal tubules by inhibiting the urate transporter ATP-binding cassette subfamily G member 2 (ABCG2). 
  • 2.6K
  • 26 Aug 2021
Topic Review
A Product/Service System
Product/service system (PSS) is widely considered as a promising design object with the potential to enhance environmental sustainability of industrial solutions. The state of the art of PSS design research includes several prescriptive PSS design support tools, methods and procedures. This body of literature has been extensively reviewed in the past. However, there is a lack of consolidation of the available prescriptive knowledge in a condensed and practically useful format that can be used by practitioners to guide their conceptual PSS design activities and by researchers to build their work on. Thus, to address this gap in our knowledge, we use an intra-disciplinary literature analysis and meta-synthesis approach to consolidate the extant prescriptive PSS design knowledge in the form of a schema for conceptual PSS design.
  • 2.6K
  • 29 Oct 2020
Topic Review
Retinal Prostheses
A retinal prosthesis, also known as a bionic eye, is a device that can be implanted to partially restore vision in patients with retinal diseases that have resulted in the loss of photoreceptors (e.g., age-related macular degeneration and retinitis pigmentosa). There have been major breakthroughs in retinal prosthesis technology, with the creation of numerous types of implants, including epiretinal, subretinal, and suprachoroidal sensors. These devices can stimulate the remaining cells in the retina with electric signals to create a visual sensation.
  • 2.6K
  • 07 Nov 2023
Topic Review
Owner and Cat Relationship
This entry provides a short overview of the different ways cat owners describe the relationship with their cat, how this might relate to an antropomorphic view of (role of) the cat, which owner-and cat-related charateristics are related to such views and how different views are associated with different living environments of cats.  
  • 2.6K
  • 24 Jan 2022
Topic Review
Dietary Natural Compounds and Vitamins Impact Uterine Fibroids
Within the past 20 year-span concerning risks of uterine fibroids (UFs) occurrence and dietary factors was carried out. A link between Vitamin D deficiency and UFs formation is strongly indicated, making it a potent compound in leiomyoma therapy. Analogs of the 25-hydroxyvitamin D3, not susceptible to degradation by tissue 24-hydroxylase, appear to be especially promising and tend to show better therapeutic results. Although research on the role of Vitamin A in the formation of fibroids is contradictory, Vitamin A-enriched diet, as well as synthetic retinoid analogues, may be preventative or limit the growth of fibroids. Unambiguous conclusions cannot be drawn regarding Vitamin E and C supplementation, except for alpha-tocopherol. Alpha-tocopherol as a phytoestrogen taking part in the modulation of estrogen receptors (ERs) involved in UF etiology, should be particularly avoided in therapy. A diet enriched in fruits and vegetables, as sources of carotenoids, polyphenols, quercetin, and indole-3-carbinol, constitutes an easily modifiable lifestyle element with beneficial results in patients with UFs. Other natural substances, such as curcumin, can reduce the oxidative stress and protect against inflammation in leiomyoma. Although the exact effect of probiotics on uterine fibroids has not yet been thoroughly evaluated at this point, the protective role of dairy products, i.e., yogurt consumption, has been indicated. Trace elements such as selenium can also contribute to antioxidative and anti-inflammatory properties of a recommended diet.
  • 2.6K
  • 11 Mar 2022
Topic Review
Recurrent and Residual Caries with Resin Composite Restorations
Caries is the most widely prevailing noncommunicable disease, and is a multifactorial process presently considered as biofilm-mediated rather than an infectious disease. According to the ecological plaque hypothesis, caries occurs as a result of an imbalance of oral microflora—normally more than 700 species—leading to an increase in cariogenic bacteria such as Streptococcus mutans and Lactobacilli types. The accumulating cariogenic bacteria produce acids such as lactic acid that reduce the local pH, leading first to demineralization and later to the destruction of the organic matrix. Caries progresses when demineralization cycles prevail and remineralization cycles cease. Classically, bacterial proteases are blamed for the proteolytic process taking place because of dental caries. Recently, it has become increasingly evident that activated endogenous matrix metalloproteinases (MMPs) and cystine cathepsins of salivary, gingival crevicular fluid and dentinal origin, together with bacterial proteases, share in degrading the dentin matrix of demineralized dentin. This takes place at neutralized pH levels where the buffering effect of saliva takes place, since MMPs operate only in neutral pH values.
  • 2.6K
  • 24 Nov 2022
Topic Review
Measuring Intraocular Pressure for Various Tonometers
Intraocular pressure (IOP) is an important measurement that needs to be taken during ophthalmic examinations, especially in ocular hypertension subjects, glaucoma patients, and patients with risk factors for developing glaucoma. The gold standard technique in measuring IOP is still Goldmann applanation tonometry (GAT); however, this procedure requires local anesthetics, can be difficult in patients with scarce compliance, surgical patients, and children, and is influenced by several corneal parameters. Numerous tonometers have been proposed in the past to address the problems related to GAT. The research describes the various devices currently in use for the measurement of intraocular pressure (IOP), highlight the main advantages and limits of the various tools. The continuous monitoring of IOP, which is still under evaluation, will be an important step for a more complete and reliable management of patients affected by glaucoma.
  • 2.6K
  • 18 Apr 2023
Topic Review
Lunar Outpost (NASA)
A lunar outpost is a concept of a permanent or semi-permanent presence of humans on the Moon, a moonbase, by the United States space administration NASA. NASA requested an increase in the 2020 budget of $1.6 billion, in order to make another crewed mission to the Moon by 2025 (originally 2024), followed by a sustained presence on the Moon by 2028.
  • 2.6K
  • 23 Nov 2022
Topic Review
Deindividuation
Deindividuation is a concept in social psychology that is generally thought of as the loss of self-awareness in groups, although this is a matter of contention (resistance) (see below). Sociologists also study the phenomenon of deindividuation, but the level of analysis is somewhat different. For the social psychologist, the level of analysis is the individual in the context of a social situation. As such, social psychologists emphasize the role of internal psychological processes. Other social sciences, such as sociology, are more concerned with broad social, economic, political, and historical factors that influence events in a given society.
  • 2.6K
  • 10 Nov 2022
Topic Review
Digital PCR and plant studies
Digital PCR (dPCR) is a breakthrough technology that able to provide sensitive and absolute nucleic acid quantification. It is a third-generation technology in the field of nucleic acid amplification. A unique feature of the technique is that of dividing the sample into numerous separate compartments, in each of which an independent amplification reaction takes place. Several instrumental platforms have been developed for this purpose, and different statistical approaches are available for reading the digital output data.
  • 2.6K
  • 16 Dec 2020
Topic Review
Teeth Eruption Disorders
Dental eruption refers to the vertical displacement of a tooth from its initial non-functional towards its functional position. Tooth eruption disorders may be expressed in various clinical conditions, which may be grouped as “primary retention” and “secondary retention”.  Tooth eruption disorders can be manifested in several clinical conditions where the oral location, the number of the affected teeth, and the etiology of the disorders vary considerably. Eruption failure is often attributed to genetic factors.
  • 2.6K
  • 27 Jul 2022
Topic Review
Prophet, Seer, and Revelator
Prophet, seer, and revelator is an ecclesiastical title used in the Latter Day Saint movement. The Church of Jesus Christ of Latter-day Saints (LDS Church) is the largest denomination of the movement, and it currently applies the terms to the members of the First Presidency and the Quorum of the Twelve Apostles. In the past, it has also been applied to the Presiding Patriarch of the church and the Assistant President of the Church. Other sects and denominations of the movement also use these terms.
  • 2.6K
  • 25 Nov 2022
Topic Review
Nicotinamide Riboside
A number of studies confirmed that measurable, biological effects on NAD+ levels can be achieved by oral NR supplementation, with no serious adverse effects. Significant increase of NAD+ levels by NR administration have been reported in whole-blood, liver, skeletal muscles, and brown adipose tissue, but not in the brain and white adipose tissue. The observed differences may be explained by differential expression of Nmrk (nicotinamide ribose kinases, NMRK1 and NMRK2) in the specific tissues. The literature gives some suggestions for the dosing of NR to achieve a desired clinical outcome. NR is considered as a safe supplement as no severe side effects are reported, as otherwise seen with other NAD+ precursers such as flushing, pruritus, hyperglycemia, hyperuricemia, or increased enzyme activity in the liver or muscles.
  • 2.6K
  • 06 Nov 2020
Topic Review
Chemical Sensor Array
A chemical sensor array is a sensor architecture with multiple sensor components that create a pattern for analyte detection from the additive responses of individual sensor components. There exist several types of chemical sensor arrays including electronic, optical, acoustic wave, and potentiometric devices, which are described below. These chemical sensor arrays can employ multiple sensor types that are cross-reactive or tuned to sense specific analytes.
  • 2.6K
  • 18 Jul 2023
Topic Review
The Versatility in the Applications of Dithiocarbamates
Dithiocarbamate ligands have the ability to form stable complexes with transition metals, and this chelating ability has been utilized in numerous applications. The complexes have also been used to synthesize other useful compounds. 
  • 2.6K
  • 10 Mar 2022
Topic Review
Houdini
Houdini is a 3D animation software application developed by Toronto-based SideFX, who adapted it from the PRISMS suite of procedural generation software tools. The procedural tools are used to produce different effects such as complex reflections, animations and particles system. Some of its procedural features have been in existence since 1987. Houdini is most commonly used for the creation of visual effects in film and television. It is used by major VFX companies such as Walt Disney Animation Studios, Pixar, DreamWorks Animation, Double Negative, ILM, MPC, Framestore, Sony Pictures Imageworks, Scanline VFX, Method Studios and The Mill. It has been used in many feature animation productions, including Disney's feature films Fantasia 2000, Frozen, Zootopia and Raya and the Last Dragon; the Blue Sky Studios film Rio, and DNA Productions' Ant Bully. SideFX also publishes Houdini Apprentice, a limited version of the software that is free of charge for non-commercial use.
  • 2.6K
  • 29 Nov 2022
Topic Review
Factors that Affect Happiness
Happiness is a crucial human disposition that denotes a construct characterizing positive feelings in individuals and overall well-being. It can be perceived as a relatively stable state linked to diverse facets of an individual’s life and distinguishes itself from more transient emotions like joy or sadness. The comprehension of happiness holds significant importance in philosophical, psychological, scholarly, narrative, and governmental spheres, but conclusive agreement regarding the factors that genuinely engender happiness remains elusive. Happiness is “commonly understood as how much one likes the life one lives” . While the meaning and attainment of happiness may differ from person to person, levels of happiness also often fluctuate from one day to the next, and a pandemic such as COVID-19 is likely to change the dynamics of existing happiness.
  • 2.6K
  • 11 Jul 2023
Topic Review
Byzantine Fault Tolerance
Byzantine fault tolerance (BFT) is the dependability of a fault-tolerant computer system, particularly distributed computing systems, where components may fail and there is imperfect information on whether a component has failed. In a "Byzantine failure", a component such as a server can inconsistently appear both failed and functioning to failure-detection systems, presenting different symptoms to different observers. It is difficult for the other components to declare it failed and shut it out of the network, because they need to first reach a consensus regarding which component has failed in the first place. The term is derived from the Byzantine Generals' Problem, where actors must agree on a concerted strategy to avoid catastrophic system failure, but some of the actors are unreliable. Byzantine fault tolerance has been also referred to with the phrases interactive consistency or source congruency, error avalanche, Byzantine agreement problem, Byzantine generals problem, and Byzantine failure.
  • 2.6K
  • 28 Nov 2022
Topic Review
Utilize Human Kinetic Energy for Sustainable Energy Generation
Renewable energy has become increasingly relevant in recent years as concerns about climate change and the depletion of fossil fuels have grown across the globe. The energy generated through exercise, sports, and other forms of physical exertion can be harnessed and used to generate electricity for homes, businesses, and even communities. This type of energy generation is becoming increasingly popular as a means of generating renewable energy and reducing our dependence on non-renewable sources of energy.
  • 2.6K
  • 18 Jul 2023
Topic Review
Biochar for Wastewater Treatment
Biochar as a stable carbon-rich material shows incredible potential to handle water/wastewater contaminants. Its application is gaining increasing interest due to the availability of feedstock, the simplicity of the preparation methods, and their enhanced physico-chemical properties. The efficacy of biochar to remove organic and inorganic pollutants depends on its surface area, pore size distribution, surface functional groups, and the size of the molecules to be removed, while the physical architecture and surface properties of biochar depend on the nature of feedstock and the preparation method/conditions. For instance, pyrolysis at high temperatures generally produces hydrophobic biochars with higher surface area and micropore volume, allowing it to be more suitable for organic contaminants sorption, whereas biochars produced at low temperatures own smaller pore size, lower surface area, and higher oxygen-containing functional groups and are more suitable to remove inorganic contaminants. In the field of water/wastewater treatment, biochar can have extensive application prospects. Biochar have been widely used as an additive/support media during anaerobic digestion and as filter media for the removal of suspended matter, heavy metals and pathogens. Biochar was also tested for its efficiency as a support-based catalyst for the degradation of dyes and recalcitrant contaminants. The current review discusses on the different methods for biochar production and provides an overview of current applications of biochar in wastewater treatment.
  • 2.6K
  • 28 Oct 2020
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