A practical reference on nootropic: what it is, how it behaves, what the literature reports, and where the honest uncertainties sit.
This page was last updated on 2025-08-01 and is reviewed periodically as new material appears.
Development is attributed to researchers at the Institute of Molecular Genetics in Moscow during the early 1980s, building on earlier Soviet work with ACTH fragments. Russian regulatory approval followed for intranasal use, and the compound has remained commercially available there for decades. Most published human data originate from Russian and, later, some Eastern European clinical reports, which are not always accessible in English translation. Outside that region the material is generally handled as a research chemical rather than a licensed medicine.
Regulatory status differs sharply between jurisdictions. In Russia the peptide is registered as a prescription nasal preparation, while agencies such as the United States Food and Drug Administration have not approved it for any indication. Products sold elsewhere are typically labeled for laboratory research only, and such labels shift responsibility for safe handling to the purchaser. Because the same name covers pharmaceutical-grade nasal drops and bulk research powder, identity and purity documentation becomes the main practical concern when comparing sources.
Reported pharmacological work centers on neurotrophic signaling, including changes in BDNF and NGF expression in hippocampal tissue in animal models. Human data come largely from studies conducted in Russia, and how well those results generalize to other populations remains an open question. Regulatory status differs sharply by jurisdiction: Semax is a registered prescription medicine in Russia, while it holds no approved marketing status in the United States or the European Union. Outside such jurisdictions it is generally handled as a research chemical, which affects both documentation and quality expectations.
Semax is a synthetic heptapeptide whose sequence is Met-Glu-His-Phe-Pro-Gly-Pro. It was developed as a fragment analog of adrenocorticotropic hormone, modeled specifically on the ACTH(4-10) region. The first four residues reproduce that fragment, while a Pro-Gly-Pro tripeptide is appended at the C-terminus. Work on the compound originated in Russia, where it entered clinical use as an intranasal preparation. Its sequence places it among short regulatory peptides studied for effects on the central nervous system rather than on the adrenal axis.
The C-terminal Pro-Gly-Pro extension is not incidental. Proline-rich tails are known to resist several common peptidases, and the published literature attributes the longer half-life of Semax, relative to unmodified ACTH fragments, to this feature. The modification also removes the melanocyte-stimulating and corticosteroidogenic activity that characterizes longer ACTH-derived sequences. Because the molecule is small and hydrophilic, it is typically formulated as an aqueous solution for intranasal or parenteral delivery. Acetylation or amidation at the termini appears in closely related research peptides and shifts the mass by a fixed increment.
| Property | Value | Notes |
|---|---|---|
| Chemical class | Synthetic heptapeptide (ACTH fragment analog) | Not a steroid; does not belong to the melanocortin agonist drugs by marketing category |
| Molecular formula | C37H51N9O10S (commonly cited) | Reported values vary slightly with salt and counter-ion content |
| Appearance | White to off-white lyophilized powder | A single batch may appear as a loose cake or fluffy solid |
| Solubility | Freely soluble in water and aqueous buffer | Stock solutions are usually prepared in sterile water or saline |
| Typical storage | −20 °C or below, desiccated and protected from light | Seal opened vials promptly to limit moisture uptake |
The parent fragment ACTH(4-10) carries the sequence Met-Glu-His-Phe-Arg-Trp-Gly. Semax replaces the arginine and tryptophan positions with a proline-glycine-proline tail, giving Met-Glu-His-Phe-Pro-Gly-Pro. That change removes residues associated with adrenal stimulation, so the peptide does not drive cortisol release the way full ACTH does. This distinction shapes how the compound is grouped in the literature, where it sits with neuropeptides and peptide neuromodulators rather than with corticosteroids.
Regulatory status varies sharply by country. Semax is registered for medical use in Russia, where it appears in formularies as a nasal solution, and it also holds registration in a small number of neighbouring states. It has no approval from the United States Food and Drug Administration or the European Medicines Agency, and it is not a scheduled controlled substance in most jurisdictions. Elsewhere it circulates mainly as laboratory material, so purity documentation comes from suppliers rather than from a national pharmacopoeia.
Semax is a synthetic heptapeptide with the sequence Met-Glu-His-Phe-Pro-Gly-Pro. It was derived from the ACTH(4-10) fragment, a short segment of adrenocorticotropic hormone that lacks the hormonal activity associated with the full-length peptide. Researchers at the Institute of Molecular Genetics in Moscow developed the compound during the 1980s. It has been registered as a pharmaceutical product in Russia and several neighbouring countries, where it is supplied as a nasal solution, and it is also sold internationally as a research chemical.
The proposed mechanism centres on neurotrophic signalling rather than direct receptor activation. Semax is reported to increase expression of brain-derived neurotrophic factor and nerve growth factor in several brain regions, and to shift the balance between excitatory and inhibitory neurotransmitter systems. Interaction with melanocortin receptors has been suggested because of the parent ACTH fragment. Many of these findings come from rodent studies, and the extent to which they translate to human physiology remains an open question.
== Further reading == Strudwick, Patrick (4 January 2014). "Crisis in South Africa: The shocking practice of 'corrective rape' – aimed at 'curing' lesbians". The Independent. Archived from the original on 1 July 2014. Retrieved 23 July 2014.
=== The "flow" === In the 1970s Csikszentmihalyi started to study flow, a state of absorption where one's abilities are well-matched to the demands at-hand. Flow is characterized by intense concentration, loss of self-awareness, a feeling of being perfectly challenged (neither bored nor overwhelmed), and a sense "time is flying". Flow is intrinsically rewarding; it can also assist in the achievement of goals (e.g., winning a game) or improving skills (e.g., becoming a better chess player). Anyone can experience flow, in different domains, such as play, creativity, and work. Flow is achieved when the challenge of the situation meets one's personal abilities. A mismatch of challenge for someone of low skills results in a state of anxiety; insufficient challenge for someone highly skilled results in boredom. The effect of challenging situations means that flow is often temporarily exciting and variously stressful, but this is considered eustress, which is also known as "good" stress. Eustress is arguably less harmful than chronic stress, although the pathways of stress-related systems are similar. Both can create a "wear and tear" effect; however, the differing physiological elements and added psychological benefits of eustress might well balance any wear and tear experienced. Csikszentmihalyi identified nine indicator elements of flow: 1. Clear goals exist every step of the way, 2. Immediate feedback guides one's action, 3. There is a balance between challenges and abilities, 4. Action and awareness are merged, 5. Distractions are excluded from consciousness, 6.
Wallace Michael Shawn (born November 12, 1943) is an American actor, essayist, and writer. He is known for playing Vizzini in The Princess Bride (1987), Mr. Hall in Clueless (1995), and Dr. John Sturgis in Young Sheldon (2017–2024), and for voicing Rex the Dinosaur in the Toy Story franchise (1995–2026). Shawn also appeared in The Bostonians (1984), Prick Up Your Ears (1987), Scenes from the Class Struggle in Beverly Hills (1989), Vanya on 42nd Street (1994), The Haunted Mansion (2003), The Incredibles (2004), Southland Tales (2006), The Double (2013), and Marriage Story (2019). He appeared in six Woody Allen films including Manhattan (1979), Radio Days (1987), and Rifkin's Festival (2020). His television work includes recurring roles as Arnie Ross in Taxi (1978-1983), Jeff Engels in The Cosby Show (1987–1991), Grand Nagus Zek in Star Trek: Deep Space Nine (1993–1999), Cyrus Rose in Gossip Girl (2008–2012), and Father Frank Ignatius in Evil (2022–2024). Shawn is also a playwright; his plays include the Obie Award–winning Aunt Dan and Lemon (1985), The Designated Mourner (1996), Grasses of a Thousand Colors (2008), and What We Did Before Our Moth Days (2026). With Andre Gregory, he wrote and starred in the 1981 drama My Dinner with Andre. He played the title role in A Master Builder (2013), a film adaptation of Henrik Ibsen's 1892 play. Haymarket Books published his books Essays (2009) and Night Thoughts (2017).
That night, an Israeli airstrike on a car in the Beqaa Valley killed two members of the Islamic Group. Targeted assassinations continued the same week with an Israeli airstrike on a car in the village of Kfar Dajjal which killed a Hezbollah member and seriously wounded three children in a nearby school bus. In response, Lebanon issued a formal complaint to the United Nations Security Council. On 25 May, an Israeli airstrike on a truck near the Syrian town of al-Qusayr killed two Hezbollah members. Later that day, a car bombing in Damascus killed a Syrian Army officer with ties to Hezbollah. On 26 May, an Israeli airstrike on a house in Aitaroun killed two Hezbollah members. On the same day, another Hezbollah member was killed, as was another person, following an airstrike on a motorcycle in Naqoura. Later, an airstrike on another motorcycle in Ayta ash Shab killed two civilians. An airstrike on a third motorcycle, in Hula, killed two Hezbollah members and wounded two other people. Two civilians were killed in strikes on the village of Yaroun. On 1 June, an Israeli airstrike on a house in Aadloun killed a civilian and wounded four others. Later that evening, two Israeli airstrikes on a house in Ain Qana killed a Hezbollah member and wounded another person. The next day, an Israeli airstrike on a motorcycle in Hula killed two civilians. On 3 June, a pair of Israeli airstrikes on Naqoura killed two Hezbollah members. Another airstrike, this time on a car near the village of Kauthariyet El Rez, killed another Hezbollah member.
High-level waste (HLW) is produced by nuclear reactors and the reprocessing of nuclear fuel. The exact definition of HLW differs internationally. After a nuclear fuel rod serves one fuel cycle and is removed from the core, it is considered HLW. Spent fuel rods contain mostly uranium with fission products and transuranic elements generated in the reactor core. Spent fuel is highly radioactive and often hot. HLW accounts for over 95% of the total radioactivity produced in the process of nuclear electricity generation but it contributes to less than 1% of volume of all radioactive waste produced in the UK. Overall, the 60-year-long nuclear program in the UK up until 2019 produced 2150 m3 of HLW. The radioactive waste from spent fuel rods consists primarily of cesium-137 and strontium-90, but it may also include plutonium, which can be considered transuranic waste. The half-lives of these radioactive elements can differ quite extremely. Some elements, such as cesium-137 and strontium-90 have half-lives of approximately 30 years. Meanwhile, plutonium has a half-life that can stretch to as long as 24,000 years. The amount of HLW worldwide is increasing by about 12,000 tonnes per year. A 1000-megawatt nuclear power plant produces about 27 tonnes of spent nuclear fuel (unreprocessed) every year. For comparison, the amount of ash produced by coal power plants in the United States is estimated at 130,000,000 t per year and fly ash is estimated to release 100 times more radiation than an equivalent nuclear power plant.
Sources: en.wikipedia.org
== Names == Dapagliflozin is the international nonproprietary name (INN), and the United States Adopted Name (USAN). The fixed-dose combination product, dapagliflozin/metformin extended-release, is sold under the brand name Xigduo XR. In July 2016, the fixed-dose combination of saxagliptin and dapagliflozin was authorized for medical use in the European Union and is sold under the brand name Qtern. The combination drug was approved for medical use in the United States in February 2017, where it also is sold under the brand name Qtern. In May 2019, the fixed-dose combination of dapagliflozin, saxagliptin, and metformin hydrochloride as extended-release tablets was approved in the United States to improve glycemic control in adults with type 2 diabetes when used in combination with diet and exercise. The FDA granted the approval of Qternmet XR to AstraZeneca. The combination drug was authorized for use in the European Union in November 2019, and is sold under the brand name Qtrilmet.
==== Natural analogues ==== Natural analogues of nicotine, often found in plants or other biological sources, include anabasine (from Anabasis aphylla), anatabine (from tobacco), arecoline (from betel nut), cotinine (major metabolite of nicotine), cytisine (from Laburnum species), and epibatidine (from frog skin), among others.
== Part II: Spatial Models and Biomedical Applications == Part II of Mathematical Biology focuses on pattern formation and applications of reaction-diffusion equations. Topics include: predator-prey interactions, chemotaxis, wound healing, epidemic models, and morphogenesis.
=== Homemade water filters === Water filters can be made on-site using local materials such as sand and charcoal (e.g. from firewood burned in a special way). These filters are sometimes used by soldiers and outdoor enthusiasts. Due to their low cost they can be made and used by anyone. The reliability of such systems is highly variable. Such filters can do little, if anything, to mitigate germs and other harmful constituents and can give a false sense of security that the water so produced is potable. Water processed through an improvised filter should undergo secondary processing such as boiling to render it safe for consumption.
Sources: en.wikipedia.org
In the 2010s, Ells tried to diversify the company by creating or acquiring several subsidiaries. These subsidiaries offered very different cuisines compared to their parent company. Examples include soul food (Soul Daddy), Asian cuisine (ShopHouse Southeast Asian Kitchen), pizza (Pizzeria Locale), and burgers (Tasty Made). In 2023, Chipotle had also tried incorporating California-inspired bowls into the Farmesa Fresh Eatery concept. The few test locations were not a financial success, and all concepts were discontinued. In 2011, Steve Ells was a judge for the TV show America's Next Great Restaurant and investor of ANGR Holdings, the company that would launch the winning concept's restaurants. Chipotle agreed to purchase Ells' investment in ANGR at his cost, provide support for ANGR operations, and invest a total of $2.3 million in cash contributions. The winning concept, Soul Daddy, was quickly closed after operating for eight weeks. In September 2011, Chipotle opened an Asian fast-casual concept restaurant named ShopHouse Southeast Asian Kitchen in Washington, D.C. The company said the new restaurant "would follow the Chipotle service format and its focus on 'food with integrity' in ingredients". Chipotle's plan was to start with only one store and see how the restaurant worked out before expanding the concept. On July 29, 2016, the company announced the opening of its first Tasty Made burger restaurant in the fall.
=== Anatomy === The blood-brain barrier protects the brain by restricting the ability of large molecules to cross the barrier between the blood, CSF, and interstitial fluid of the brain. ICV injection circumvents this barrier, to be able to deliver drugs to the CSF. An ICV device is implanted under the scalp, into the subgaleal space where it is then connected to the ventricles with an outlet catheter. This allows for repeated doses of the drug without having to re-puncture the scalp. Production of CSF is at a rate of about .3 mL/minute and occurs at the ependymal and parenchymal regions and the choroid plexus. Up to 80 percent of CSF production comes from the choroid plexus, which is present within the lateral, third, and fourth ventricles. The choroid is lined with epithelium with tight junctions at the ventricular side of the cells. This comprises the blood-CSF barrier. Whereas the blood-brain barrier is made up of vascular endothelium in capillary beds throughout the CNS parenchyma.
==== Blood-borne stimuli ==== Peptide hormones have important influences upon the hypothalamus, and to do so they must pass through the blood–brain barrier. The hypothalamus is bounded in part by specialized brain regions that lack an effective blood–brain barrier; the capillary endothelium at these sites is fenestrated to allow free passage of even large proteins and other molecules. Some of these sites are the sites of neurosecretion - the neurohypophysis and the median eminence. However, others are sites at which the brain samples the composition of the blood. Two of these sites, the SFO (subfornical organ) and the OVLT (organum vasculosum of the lamina terminalis) are so-called circumventricular organs, where neurons are in intimate contact with both blood and CSF. These structures are densely vascularized, and contain osmoreceptive and sodium-receptive neurons that control drinking, vasopressin release, sodium excretion, and sodium appetite. They also contain neurons with receptors for angiotensin, atrial natriuretic factor, endothelin and relaxin, each of which important in the regulation of fluid and electrolyte balance. Neurons in the OVLT and SFO project to the supraoptic nucleus and paraventricular nucleus, and also to preoptic hypothalamic areas. The circumventricular organs may also be the site of action of interleukins to elicit both fever and ACTH secretion, via effects on paraventricular neurons. It is not clear how all peptides that influence hypothalamic activity gain the necessary access.
Sources: en.wikipedia.org
It is a short synthetic peptide built from seven amino acids: methionine, glutamic acid, histidine, phenylalanine and three prolines. The sequence derives from the 4-10 fragment of adrenocorticotropic hormone with an added proline-glycine-proline tail. No plant or animal extract is involved; the material is produced by solid-phase peptide synthesis.
It was developed in the Soviet Union during the early 1980s by groups at the Institute of Molecular Genetics in Moscow. Russian approval for intranasal use followed, and it has been marketed there since. Western laboratories encountered it mainly through translated literature and, later, through online research-chemical trade.
It holds a Russian registration as a prescription nasal product but has no approval from the European Medicines Agency or the United States Food and Drug Administration. Buyers outside Russia usually receive material sold strictly for laboratory research. That distinction matters because research-grade and pharmaceutical-grade products carry different documentation and testing expectations.
The sequence is Met-Glu-His-Phe-Pro-Gly-Pro, a seven-residue peptide. The first four residues correspond to the ACTH(4-10) fragment, and Pro-Gly-Pro is added at the C-terminus. N-acetylated versions also appear in the literature and differ in mass.