This is a working overview of circadian rhythm, written for readers who want more than a one-paragraph summary but less than a textbook.
This page was last updated on 2026-03-01 and is reviewed periodically as new material appears.
Regulatory treatment of SR9009 reflects its investigational status. The compound has no approved human therapeutic indication, and sports authorities prohibit its use. It appears on anti-doping lists as a non-approved substance or metabolic modulator, depending on the list version. Products sold online as research chemicals are not quality-controlled medicines, so their identity and purity can differ from the label. Such products may also contain unlisted compounds, which complicates both testing and safety assessment.
Scientific discussion of SR9009 often separates animal evidence from human anecdote. Rodent studies provide controlled data on endurance, metabolism, and gene expression, but they use specific strains, doses, and treatment durations. Human reports are mostly uncontrolled and cannot establish cause and effect. Open questions include oral bioavailability, tissue distribution, metabolic stability, and long-term effects. Review articles generally call for more rigorous pharmacokinetic and safety research before any clinical use could be considered.
Analytical methods for SR9009 typically rely on liquid chromatography coupled with tandem mass spectrometry. The technique can separate the parent compound from related substances and detect low concentrations in biological matrices. Urine and blood are common samples in anti-doping testing, while in vitro studies may use cell culture media. Rapid metabolism and low expected concentrations make method validation important for reliable identification. Exact metabolite patterns can vary by species and are not fully mapped.
SR9009 is a synthetic small molecule studied as a REV-ERB agonist. REV-ERBα and REV-ERBβ are nuclear receptors that help regulate circadian rhythms and metabolic gene expression. The compound was identified in academic screening efforts to find synthetic ligands for these receptors. In cell and animal studies, SR9009 alters transcription of genes involved in lipid and glucose metabolism, and it can shift circadian behavior. It is not an approved therapeutic agent.
Mechanistically, SR9009 binds the ligand-binding domain of REV-ERBα/β and enhances recruitment of corepressor complexes. This represses target genes rather than activating them. Because REV-ERB proteins normally compete with ROR proteins at shared response elements, the net effect depends on tissue and timing. Researchers use SR9009 to probe how nuclear receptor signaling links the clock to metabolism, inflammation, and muscle biology. Findings are largely preclinical, and the precise contribution of each receptor subtype remains under study.
| Property | Value | Notes |
|---|---|---|
| Regulatory status | Not approved for human use | Investigational status in most countries |
| Sports status | Prohibited by WADA | Classified as non-approved or metabolic modulator |
| Common analytical method | LC-MS/MS | Used for trace detection in biological samples |
| Typical test matrices | Urine and blood | Sample choice depends on testing program |
| Human trial data | None published | Effects and safety are not established |
Physicochemical behavior influences handling. SR9009 is described as a solid with limited aqueous solubility, so organic solvents such as dimethyl sulfoxide or ethanol are common in research stock solutions. Aqueous dilution can produce precipitates if the organic content is too low. Light, heat, and repeated freeze-thaw cycles may affect stability. Storage recommendations usually specify a desiccated freezer environment protected from light, but exact stability data depend on the formulation and matrix.
Detection in biological samples can be complicated by rapid metabolism and low circulating concentrations. Some studies report phase I and phase II metabolites, and analytical methods may need to target those species in addition to the parent compound. Immunoassays are not broadly available, so mass spectrometry remains the main confirmatory approach. For anti-doping testing, laboratories look for SR9009 and its metabolites using validated LC-MS methods. Open questions include how long metabolites remain detectable and how different routes of administration alter detection windows.
In laboratory settings, SR9009 is typically characterized by liquid chromatography–mass spectrometry (LC-MS) or high-performance liquid chromatography with ultraviolet detection (HPLC-UV). These methods can confirm identity and estimate purity, but they require reference standards for accurate quantification. Because SR9009 is not a licensed pharmaceutical, no harmonized pharmacopeial monograph exists. Laboratories often validate in-house methods for matrices such as plasma, urine, or cell culture media. Sample preparation may involve protein precipitation or liquid-liquid extraction before analysis.
Laboratory studies often administer SR9009 by injection because oral absorption appears poor in rodents. Reported pharmacokinetic properties include rapid metabolism and low systemic exposure after oral dosing. Human pharmacokinetic data are sparse, so absorption, distribution, metabolism, and excretion in people are not well defined. Some research explores related REV-ERB compounds with improved drug-like properties. Regulatory approval for any REV-ERB agonist as a human medicine has not been granted to date.
SR9009 is a synthetic small molecule studied as an agonist of the nuclear receptors REV-ERBα and REV-ERBβ, also called NR1D1 and NR1D2. These receptors help regulate circadian rhythms and metabolic gene programs. The compound was developed for laboratory research, not as an approved therapeutic. Its identity is distinct from steroid hormones and selective androgen receptor modulators. Scientific interest centers on how REV-ERB activation changes gene expression in cells and animal models.
At the molecular level, SR9009 binds the ligand-binding domain of REV-ERB and strengthens recruitment of corepressor proteins such as NCoR and HDAC3. This increases repression of target genes, including Bmal1 and other clock-controlled and metabolic genes. In rodent studies, such changes have been linked to altered lipid handling, glucose metabolism, and energy expenditure. The precise chain of events between receptor binding and whole-body effects remains an active area of research. Findings in animals do not automatically translate to humans.
Regulatory agencies have not approved SR9009 for human therapeutic use. It is typically sold as a research chemical with labels stating that it is not for human consumption. The World Anti-Doping Agency prohibits the substance in sport, generally under the category of non-approved substances. Customs and national laws may restrict importation, sale, or possession. Product quality and legal status can vary by country and vendor, and therapeutic claims are not permitted in regulated advertising because the compound lacks approval.
Several misconceptions surround SR9009. It is often described as a SARM, a steroid, or an exercise pill, but its known target is the REV-ERB receptor family. Rodent studies have examined exercise capacity and metabolic markers, yet human outcomes remain unproven. Oral bioavailability appears low in animals, and human pharmacokinetics are not well characterized. Online products may contain impurities or different compounds, so identity and purity testing are important for research use.
Pharmacokinetic data for SR9009 are limited in published literature. Some reports indicate low oral bioavailability and rapid clearance in animals, which complicates interpretation of exposure and effect. Researchers often use injected routes in preclinical work to achieve measurable systemic levels. Analytical studies rely on mass spectrometry to detect the parent compound and its metabolites. Questions about tissue distribution, active metabolites, and long-term consequences remain open. Species differences in metabolism can affect observed half-life and target engagement.
SR9009 is a synthetic small molecule studied as an agonist of the nuclear receptors REV-ERBα and REV-ERBβ. These receptors help regulate circadian rhythms and metabolic gene expression. In laboratory experiments, SR9009 binds these receptors and alters transcription of genes involved in lipid handling, glucose metabolism, and mitochondrial function. It is not a naturally occurring compound and has no approved therapeutic use. Research interest stems from its ability to modify energy metabolism in cells and animal models.
Like PAH metabolites, acrolein is also an electrophilic alkylating agent and permanently binds to the DNA base guanine, by a conjugate addition followed by cyclization into a hemiaminal. The acrolein-guanine adduct induces mutations during DNA copying and thus causes cancers in a manner similar to PAHs. However, acrolein is 1000 times more abundant than PAHs in cigarette smoke and can react without metabolic activation. Acrolein has been shown to be a mutagen and carcinogen in human cells. The carcinogenicity of acrolein has been difficult to study by animal experimentation, because it has such a toxicity that it tends to kill the animals before they develop cancer. Generally, compounds able to react by conjugate addition as electrophiles (so-called Michael acceptors after the Michael reaction) are toxic and carcinogenic, because they can permanently alkylate DNA, similarly to mustard gas or aflatoxin. Acrolein is only one of them present in cigarette smoke; for example, crotonaldehyde has been found in cigarette smoke. Michael acceptors also contribute to the chronic inflammation present in diseases brought about by smoking. Nitrosamines are a group of carcinogenic compounds found in cigarette smoke but not in uncured tobacco leaves. Nitrosamines form on flue-cured tobacco leaves during the curing process through a chemical reaction between nicotine and other compounds contained in the uncured leaf and various oxides of nitrogen found in all combustion gases. Switching to indirect fire curing has been shown to reduce nitrosamine levels to less than 0.1 parts per million.
DNA profiling is also used successfully to positively identify victims of mass casualty incidents, bodies or body parts in serious accidents, and individual victims in mass war graves, via matching to family members. DNA profiling is also used in DNA paternity testing to determine if someone is the biological parent or grandparent of a child with the probability of parentage is typically 99.99% when the alleged parent is biologically related to the child. Usually DNA sequencing are carried out after birth, but there are new methods to test paternity while a mother is still pregnant.
In 2008, Russia began a cyber attack on the Georgian government website, which was carried out along with Georgian military operations in South Ossetia. In 2008, Chinese "nationalist hackers" attacked CNN as it reported on Chinese repression on Tibet. Hackers from Armenia and Azerbaijan have actively participated in cyberwarfare as part of the Nagorno-Karabakh conflict, with Azerbaijani hackers targeting Armenian websites and posting Ilham Aliyev's statements. Jobs in cyberwarfare have become increasingly popular in the military. All four branches of the United States military actively recruit for cyber warfare positions. In a 2024 study on the use of military cyber operations during the Russo-Ukrainian War, Frederik A. H. Pedersen and Jeppe T. Jacobsen concluded that cyber operations in warfare may only be impactful on the tactical and operational levels in a war's beginning, when cyber and non-cyber operations can be aligned and complex cyber weapons can be prepared before war breaks out, as well as cumulatively on a strategic level.
Sources: en.wikipedia.org
Narrated by actress Nicola Duffett, directed by Gary Johnstone, produced by Paul Wilmshurst 18 September Coral Grief, 50 million years ago, northern Italy was under water; David Bellwood of James Cook University; David Barnes of the Australian Institute of Marine Science; biologist Garry Russ; the Florida Reef and Craig Quirolo; a 1970 episode of Four Corners (Australian TV program); Peter Moran and Sea star wasting disease; Peter Isdale and Bette Willis; biologist Angel Alcala of Silliman University, who was Secretary of Environment and Natural Resources from 1992–95; Peter Harrison of the National Marine Science Centre, Australia; geochemist Michael Gagan of the Australian National University.
The trivial (non-systematic) name for alkanes is "paraffins". Together, alkanes are known as the "paraffin series". Trivial names for compounds are usually historical artifacts. They were coined before the development of systematic names, and have been retained due to familiar usage in industry. Cycloalkanes are also called naphthenes. Branched-chain alkanes are called isoparaffins. "Paraffin" is a general term and often does not distinguish between pure compounds and mixtures of isomers, i.e., compounds of the same chemical formula, e.g., pentane and isopentane.
The lightweight chain of a bicycle with derailleur gears can snap (or rather, come apart at the side-plates, since it is normal for the "riveting" to fail first) because the pins inside are not cylindrical, they are barrel-shaped. Contact between the pin and the bushing is not the regular line, but a point which allows the chain's pins to work its way through the bushing, and finally the roller, ultimately causing the chain to snap. This form of construction is necessary because the gear-changing action of this form of transmission requires the chain to both bend sideways and to twist, but this can occur with the flexibility of such a narrow chain and relatively large free lengths on a bicycle. Chain failure is much less of a problem on hub-geared systems since the chainline does not bend, so the parallel pins have a much bigger wearing surface in contact with the bush. The hub-gear system also allows complete enclosure, a great aid to lubrication and protection from grit.
Logan Roy's character was heavily influenced both by powerful real-world figures and prior performances in Shakespearean dramas by Cox. Opposite to his children's privileged upbringing, Logan comes from a working-class background, with Cox describing him as coming from "a different generation and has a different set of values." Cox has noted that portraying Logan gave him the habit of frequently using profanity in his everyday life. In contrast to the vigorous routine done by his co-star Jeremy Strong, Cox has dismissed the concept of method acting in preparation for his roles, calling it "bollocks."
Sources: en.wikipedia.org
=== Peak width definition === In the peak width definition, the value of ΔM is the width of the peak measured at a specified fraction of the peak height, for example 0.5%, 5%, 10% or 50%. The latter is called the full width at half maximum (FWHM).
Illegal efforts to weaponize methaqualone have occurred. During the 1980s, the apartheid regime in South Africa ordered the covert manufacture of a large amount of methaqualone at the front company Delta G Scientific Company, as part of a secret chemical weapons program known as Project Coast. Methaqualone was given the codename MosRefCat (Mossgas Refinery Catalyst). Details of this activity came to light during the 1998 hearings of the post-apartheid Truth and Reconciliation Commission.
=== Selected articles === Vom Saal, F. S., Akingbemi, B. T., Belcher, S. M., Birnbaum, L. S., Crain, D. A., Eriksen, M., ... & Zoeller, R. T. (2007). Chapel Hill bisphenol A expert panel consensus statement: integration of mechanisms, effects in animals and potential to impact human health at current levels of exposure. Reproductive Toxicology, 24(2), 131–138. LeBlanc G.A. (2007). Crustacean endocrine toxicology: a review. Ecotoxicology, 16, 61–81. Camp A. A., Yun J., Chambers S. A., Maher H. H., LeBlanc G. A. (2020). Involvement of glutamate and serotonin transmitter systems in male sex determination in Daphnia pulex. Journal of Insect Physiology. 121: doi.org/10.1016/j.jinsphys.2020.104015. Xu, X., Zhou, G., Lei, K., LeBlanc, G. A., & An, L. (2020). Phthalate esters and their potential risk in PET bottled water stored under common conditions. International Journal of Environmental Research and Public Health, 17(1), 141. Ford, A. T., & LeBlanc, G. A. (2020). Endocrine disruption in invertebrates: A survey of research progress. Environmental Science & Technology, 54(21), 13365–13369. Morthorst J.E, Holbech H., De Croze N., Mattiessen P., & LeBlanc G.A. (2022). Thyroid-like hormone signaling in invertebrates and its potential role in initial screening of thyroid hormone system disrupting chemicals. Integrative Environmental Assessment & Management. 18:62-82.
Periodontal pocket formation Gingival ulceration and suppuration Destruction of the alveolar bone and periodontal ligament Tooth mobility, drifting and eventual loss Because bone loss makes its first appearance in the advanced lesion, it is equated with periodontitis, while the first three lesions are classified as gingivitis in levels of increasing severity. The advanced lesion is no longer localized to the area around the gingival sulcus but spreads apically as well as laterally around a tooth and perhaps even deep into the gum tissue papilla. There is a dense infiltrate of plasma cells, other lymphocytes and macrophages. The clusters of perivascular plasma cells still appears from the established lesion. Bone is resorbed, producing scarring and fibrous change.
== Pharmacology == Lorazepam has anxiolytic, sedative, hypnotic, amnesic, anticonvulsant, and muscle relaxant properties. It is a high-potency and an intermediate-acting (10–20 hour half-life) benzodiazepine, and its uniqueness, advantages, and disadvantages are largely explained by its pharmacokinetic properties (poor water and lipid solubility, high protein binding and anoxidative metabolism to a pharmacologically inactive glucuronide form) and by its high relative potency (lorazepam 1 mg is equal in effect to diazepam 10 mg). The biological half-life of lorazepam is 10–20 hours.
Sources: en.wikipedia.org
No. It is an investigational compound without approved therapeutic indications. It is sold for research purposes only in many jurisdictions.
Sports authorities prohibit it because it is not approved for human use and has potential performance-enhancing effects. It appears on anti-doping lists under non-approved or metabolic modulator categories.
Detection usually uses liquid chromatography-tandem mass spectrometry. The method targets the parent compound or its metabolites in urine or blood.
SR9009 is a synthetic compound investigated as an agonist of the nuclear receptors REV-ERBα and REV-ERBβ. It is used in preclinical research on circadian rhythm and metabolism. It is not an approved drug.