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Topic Review
The Medicinal Chemistry of Artificial Nucleic Acids
Nucleic acids play a central role in human biology, making them suitable and attractive tools for therapeutic applications. While conventional drugs generally target proteins and induce transient therapeutic effects, nucleic acid medicines can achieve long-lasting or curative effects by targeting the genetic bases of diseases.
  • 2.4K
  • 05 Aug 2022
Topic Review
2015–16 Zika Virus Epidemic
In early 2015, a widespread epidemic of Zika fever, caused by the Zika virus in Brazil , spread to other parts of South and North America. It also affected several islands in the Pacific, and Southeast Asia. In January 2016, the World Health Organization (WHO) said the virus was likely to spread throughout most of the Americas by the end of the year. In November 2016 WHO announced the end of the Zika epidemic. In February 2016, WHO declared the outbreak a Public Health Emergency of International Concern as evidence grew that Zika can cause birth defects as well as neurological problems. The virus can be transmitted from an infected pregnant woman to her fetus, then can cause microcephaly and other severe brain anomalies in the infant. Zika infections in adults can result in Guillain–Barré syndrome. Prior to this outbreak, Zika was considered a mild infection, as most Zika virus infections are asymptomatic, making it difficult to determine precise estimates of the number of cases. In approximately one in five cases, Zika virus infections result in Zika fever, a minor illness that causes symptoms such as fever and a rash. The virus is spread mainly by the Aedes aegypti mosquito, which is commonly found throughout the tropical and subtropical Americas. It can also be spread by the Aedes albopictus ("Asian tiger") mosquito, which is distributed as far north as the Great Lakes region in North America. Men infected with Zika can transmit the virus to their sexual partners. A number of countries have issued travel warnings, and the outbreak is expected to reduce tourism significantly. Several countries have taken the unusual step of advising their citizens to delay pregnancy until more is known about the virus and its impact on fetal development. Furthermore, the outbreak raised concerns regarding the safety of athletes and spectators at the 2016 Summer Olympics in Rio de Janeiro. In Brazil, the Zika virus epidemic revealed structural problems of the health system, in particular in public health services and basic sanitation.
  • 2.4K
  • 29 Sep 2022
Topic Review
Gorch Fock (1958)
The Gorch Fock is a tall ship of the German Navy (Deutsche Marine). She is the second ship of that name and a sister ship of the Gorch Fock built in 1933. Both ships are named in honour of the German writer Johann Kinau who wrote under the pseudonym "Gorch Fock" and died in the battle of Jutland/Skagerrak in 1916. The modern-day Gorch Fock was built in 1958 and has since then undertaken 146 cruises (as of October 2006), including one tour around the world in 1988. She is sometimes referred to (unofficially) as the Gorch Fock II to distinguish her from her older sister ship. The Gorch Fock is under the command of the Naval Academy in Flensburg-Mürwik.
  • 2.4K
  • 26 Oct 2022
Topic Review
Cicisbeo
In 18th- and 19th-century Italy, the cicisbeo (Italian pronunciation: [tʃitʃizˈbɛːo]; plural: cicisbei), or cavalier servente (chevalier servant in French), was the professed gallant and perhaps lover in a sexual sense of a married woman, who attended her at public entertainments, to church and other occasions and had privileged access to his mistress. The arrangement is comparable to the Spain cortejo or estrecho and, to a lesser degree, to the France petit-maître. The exact etymology of the word is unknown; some evidence suggests it originally meant "in a whisper" (perhaps an onomatopeic word). Other accounts suggest it is an inversion of bel cece, which means "beautiful chick (pea)". According to OED, the first recorded usage of the term in English was found in a letter by Lady Mary Wortley Montagu dated 1718. The term appears in Italian in Giovanni Maria Muti's "Quaresimale Del Padre Maestro Fra Giovanni Maria Muti De Predicatori" of 1708 (p. 734).
  • 2.4K
  • 22 Nov 2022
Topic Review
Polymer-Based Materials for Space Radiation Shielding
Space exploration requires the use of suitable materials to protect astronauts and spacecraft components (e.g. onboard electronics) from the hazardous effects of radiation, in particular, ionizing radiation, which is ubiquitous in the hostile space environment. In this scenario, polymer-based materials and composites play a crucial role in achieving effective radiation shielding while providing low-weight and tailored mechanical properties to different types of spacecraft elements.
  • 2.4K
  • 21 Mar 2024
Topic Review
Avocado Peel Extracts in Topical Formulations
The avocado fruit, a derivative of the avocado tree of botanical name Persea americana Mill.. Avocado peel is a cheap and promising option for the retrieval of phenolic compounds, and it was reported that this by-product possesses higher total phenolic content, radical scavenging capacity, and antioxidant activity compared to the pulp. These results highlight the possibility of obtaining sustainable cosmetics, reducing significantly the negative impacts on the environment by the incorporation of extracts sourced from the avocado peel, an  interesting source of phenolic compounds, abundant and low-cost by-product.
  • 2.4K
  • 18 Mar 2022
Topic Review
Let's Encrypt
Let's Encrypt is a certificate authority that provides X.509 certificates for Transport Layer Security (TLS) encryption at no charge. The certificate is valid for 90 days, during which renewal can take place at anytime. The offer is accompanied by an automated process designed to overcome manual creation, validation, signing, installation, and renewal of certificates for secure websites. It launched on April 12, 2016. The project claims to make encrypted connections to World Wide Web servers ubiquitous. By eliminating payment, web server configuration, validation email management and certificate renewal tasks, it is meant to significantly lower the complexity of setting up and maintaining TLS encryption. On a Linux web server, execution of only two commands is sufficient to set up HTTPS encryption and acquire and install certificates. To that end, a software package was included into the official Debian and Ubuntu software repositories. Current initiatives of major browser developers such as Mozilla and Google to deprecate unencrypted HTTP are counting on the availability of Let's Encrypt. The project is acknowledged to have the potential to accomplish encrypted connections as the default case for the entire web. Only domain-validated certificates are being issued, since they can be fully automated. Organization Validation and Extended Validation Certificates are not available. By being as transparent as possible, they hope to both protect their own trustworthiness and guard against attacks and manipulation attempts. For that purpose they regularly publish transparency reports, publicly log all ACME transactions (e.g. by using Certificate Transparency), and use open standards and free software as much as possible. Support of ACME v2 and wildcard certificates was added in March 2018.
  • 2.4K
  • 23 Nov 2022
Topic Review
Acetylation
Acetylation, also known as acetylation or acetylation, refers to the chemical reaction of adding an acetyl functional group to an organic compound. Conversely, the reaction in which the acetyl group is removed is called deacetylation or deacetylation. Acetylation of proteins is a post-translational modification.
  • 2.4K
  • 16 Nov 2022
Topic Review
Fused Deposition Modeling and 3D Printing
The operating principle of 3D printing is the layer-by-layer fabrication of objects, using a digital design. Before printing, a 3D digital model of the object is created with a computer-aided design (CAD) software, offering the ability of designing various complex final structures. The structure is then “sliced” in 2D layers which are printed one by one, on top of each other, in order to finally afford the 3D object. Stereolithography, which is based on the selective photo-polymerization of a liquid resin, was the first technique developed for 3D printing technology. Two other methods have mainly been employed for printing polysaccharides: fused deposition modeling (FDM), mostly for cellulose and its derivatives, owing to the good processing window between their glass transition temperature and the onset of thermal degradation temperature; and extrusion-based printing, which is appropriate for hydrogels.
  • 2.4K
  • 11 Feb 2022
Topic Review
Cerberin
Cerberin is a type of cardiac glycoside, a steroidal class found in the seeds of the dicotyledonous angiosperm genus Cerbera; including the suicide tree (Cerbera odollam) and the sea mango (Cerbera manghas). This class includes digitalis-like agents, channel-blockers that as a group have found historic uses as cardiac treatments, but which at higher doses are extremely toxic; in the case of cerberin, consumption of the C. odollam results in poisoning with presenting nausea, vomiting, and abdominal pain, often leading to death. The natural product has been structurally characterized, its toxicity is clear—it is often used as an intentional human poison in third-world countries, and accidental poisonings with fatalities have resulted from individuals even indirectly consuming the agent—but its potentially therapeutic pharmacologic properties are very poorly described.
  • 2.4K
  • 10 Nov 2022
Topic Review
Irrigation in Al-Andalus
The Berber and Arab conquest of the Iberian Peninsula in 711 C.E. led to a profound transformation of the agricultural landscape. The layout of the irrigated areas, both rural and urban, is recognisable because it is the result of social and technological choices. But irrigated agriculture was not the only option in Al-Andalus.
  • 2.4K
  • 29 Jan 2024
Topic Review
Erectile Dysfunction
Erectile dysfunction (ED), also called impotence, is the type of sexual dysfunction in which the penis fails to become or stay erect during sexual activity. It is the most common sexual problem in men. Through its connection to self-image and to problems in sexual relationships, erectile dysfunction can cause psychological harm. In about 80% of cases, physical causes can be identified. These include cardiovascular disease; diabetes mellitus; neurological problems, such as those following prostatectomy; hypogonadism; and drug side effects. About 10% of cases are psychological impotence, caused by thoughts or feelings; here, there is a strong response to placebo treatment. The term erectile dysfunction is not used for other disorders of erection, such as priapism. Treatment involves addressing the underlying causes, lifestyle modifications, and addressing psychosocial problems. In many cases, treatment is attempted by drugs, specifically PDE5 inhibitors (such as sildenafil), which dilate blood vessels, allowing more blood to flow through the spongy tissue of the penis (akin to opening a valve further in order to allow more water to enter a fire hose). Other treatments, less commonly used, include prostaglandin pellets, inserted in the urethra; smooth-muscle relaxants and vasodilators, injected into the penis; penile implants; penis pumps; and vascular reconstructive surgery.
  • 2.4K
  • 29 Nov 2022
Topic Review
Diet, the Microbiome, and the Intestinal Health
The gut microbiome, or gut microbiota, also termed commensal, refers to the entire microbial community that populates the mammalian gastrointestinal (GI) tract, with the majority residing in the colon. Alterations of the gut microbiome are implicated in many gastrointestinal diseases, such as inflammatory bowel disease (IBD). Food components in our diet provide not only nutrients to our body but also substrates for the gut microbial flora. What we eat shapes the structure, composition, and function of the gut microbiome, which interacts with the gut epithelium and mucosal immune system and maintains intestinal homeostasis in a healthy state. There is growing interest in nutritional therapy to target the gut microbiome in IBD. 
  • 2.4K
  • 30 Aug 2022
Topic Review
LBRY
LBRY (/ˈlaɪbrɛri/), is a blockchain-based file-sharing and payment network that powers decentralized platforms, primarily social networks and video platforms. LBRY's creators also created Odysee, an open-source video-sharing website that uses the network, and that was split into a separate company on October 1, 2021. Video platforms built on LBRY, such as Odysee, have been described as decentralized alternatives to YouTube. The company has described Odysee and other platforms it has built utilizing its LBRY protocol as platforms for free speech and lightly moderates content, including removing pornography or the promotion of violence and terrorism.
  • 2.4K
  • 07 Nov 2022
Topic Review
The Larva of the Ascidian Halocynthia roretzi
The swimming larva represents the dispersal phase of ascidians, marine invertebrates belonging to tunicates. Due to its adhesive papillae, the larva searches the substrate, adheres to it, and undergoes metamorphosis, thereby becoming a sessile filter feeding animal. The papillae of H. roretzi, previously described as simple and conform, exhibit dynamic changes during settlement. This opens up new considerations on papillae morphology and evolution and deserves to be further investigated.
  • 2.4K
  • 31 Dec 2021
Topic Review
Sulfamethoxazole in Water
Sulfamethoxazole (SMX) is a frequently used antibiotic for the treatment of urinary tract, respiratory, and intestinal infections and as a supplement in livestock or fishery farming to boost production.
  • 2.4K
  • 30 Nov 2021
Topic Review
In Vitro Maturation (IVM) of Human Oocyte
The clinical human oocyte IVM refers to in vitro maturation of the immature oocytes retrieved from follicles after no follicle stimulating hormone (FSH) or minimal FSH stimulation (usually 3 days' stimulation), followed by no human chorionic gonadotrophin (hCG) or minimal hCG priming (single 10,000 IU injection).
  • 2.4K
  • 28 Dec 2021
Topic Review
Geographic Information Systems Within Enterprise Resource Planning Systems
Geographic information systems (GIS) have become very important tools in many areas in recent years, including resource management and utilization in many industries. GISs are sometimes referred to as computer tools, but sometimes they are defined as information systems consisting of software and database.
  • 2.4K
  • 09 Aug 2022
Topic Review
Mobile DNA
Mobile DNA is DNA that able to move to new locations throughout the genome. This process of movement is often called transposion, and the mobile DNA, transposons. Some mobile DNAs move by different mechanisms to transposons, but have similarities.
  • 2.4K
  • 27 Sep 2022
Topic Review Peer Reviewed
Philosophical Genealogy
Philosophical genealogy constitutes a mode of inquiry that investigates either (a) the historical emergence of contemporary ideas, institutions, religions, moral norms, and even affective dispositions by tracing them to the intersection of diverse and often heterogeneous historical practices, beliefs, customs, and technologies or (b) demonstrates how a phenomenon could have emerged by providing a pragmatic reconstruction of the object under investigation. The following entry endeavors to explore various formulations of the genealogical method.
  • 2.4K
  • 12 Sep 2025
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