A practical reference on elevated plus maze: what it is, how it behaves, what the literature reports, and where the honest uncertainties sit.
Reviewed 2026-05-14. Anything still debated is marked as such rather than presented as settled.
Pharmacokinetic data are sparse and largely derived from animal work. After intranasal administration the peptide appears in plasma within minutes, and reported half-lives are short, on the order of minutes to tens of minutes. Degradation proceeds through ordinary proteolytic cleavage into constituent amino acids and smaller fragments. Direct evidence that intact Selank reaches brain tissue in meaningful amounts is limited, and the extent of blood-brain barrier penetration is debated. Some authors argue that fragments, not the parent peptide, carry much of the observed activity.
Published clinical work is concentrated in Russian-language journals and generally involves small samples without independent replication. Systematic reviews in English note the shortage of randomised, placebo-controlled trials and the difficulty of verifying methods from translated reports. Outcome measures vary between studies, which complicates pooling of results. Interest in the compound as a cognitive or anxiolytic agent therefore rests on a thinner evidence base than the volume of citations suggests. Replication in well-powered trials with preregistered endpoints would be needed before firm conclusions about efficacy can be drawn.
Selank is a synthetic heptapeptide developed in Russia during the 1990s. Researchers at the Institute of Molecular Genetics of the Russian Academy of Sciences designed it as a stabilized analog of tuftsin, a naturally occurring immunomodulatory tetrapeptide. The compound has been studied primarily for its reported anxiolytic and nootropic effects. It remains largely unknown in Western pharmacology and is not approved as a medicine by major regulators such as the FDA or the EMA.
The primary structure of Selank is Thr-Lys-Pro-Arg-Pro-Gly-Pro, corresponding to the molecular formula C33H57N11O9 and a monoisotopic mass of roughly 751.9 daltons. The N-terminal threonine and the arginine residue in the fourth position are shared with tuftsin, which carries the sequence Thr-Lys-Pro-Arg. The three additional residues at the C-terminus, Pro-Gly-Pro, extend the chain and are associated with greater resistance to enzymatic degradation. This extension also separates Selank from the shorter parent peptide.
| Property | Value | Notes |
|---|---|---|
| Primary route studied | Intranasal | Also examined parenterally in animal work |
| Reported plasma half-life | Minutes to tens of minutes | Values vary widely between reports |
| Main model systems | Rodent behavioural and cell assays | Human trials are few and small |
| Principal proposed targets | GABA-A receptor, GABA transaminase | Monoamine and neurotrophic pathways also reported |
| Evidence grade | Preliminary | Limited independent replication |
Laboratory work relies on standard behavioral paradigms. Rodents are tested in the elevated plus maze, open field, and passive avoidance tasks, with outcomes compared against diazepam or vehicle controls. Intranasal dosing is used most often because it bypasses first-pass metabolism, though intraperitoneal and intravenous routes also appear in published protocols. Biochemical endpoints include tissue BDNF concentrations, cytokine levels, and monoamine metabolites. Human data are limited to small Russian trials reporting reduced anxiety scores; most were not prospectively registered, and few employed independent outcome assessment.
Measuring peptide exposure inside the brain is technically difficult. Selank is degraded rapidly in plasma, and assays must separate intact peptide from fragments, which favors targeted mass spectrometry over immunoassays alone. Reported half-lives are short, on the order of minutes, so effects observed hours later are attributed to downstream signaling rather than to the parent compound. Blood-brain barrier permeability is debated and rarely quantified directly. Gaps include absent dose-response characterization, inconsistent reporting of purity, and almost no pharmacokinetic data from human participants.
Selank is studied chiefly as an animal-model anxiolytic with proposed secondary effects on memory and immune signaling. Reported mechanisms include modulation of the GABA-A receptor complex, inhibition of enkephalin-degrading enzymes, and shifts in monoamine turnover within limbic structures. Some experiments describe increased expression of brain-derived neurotrophic factor in the hippocampus after repeated dosing. No single molecular target has been confirmed, and the peptide does not bind any receptor with the selectivity typical of a conventional small-molecule drug. Mechanism therefore remains a set of hypotheses rather than an established pathway.
Proposed mechanisms center on modulation of the GABA system, but no single molecular target has been confirmed. Rodent studies report changes in GABA-A receptor expression and in the turnover of serotonin, dopamine, and norepinephrine in several brain regions. Increases in brain-derived neurotrophic factor and its receptor have also been described after repeated administration. These findings come largely from animal models, and the degree to which they describe human neurochemistry remains an open question. The mechanism is best characterized as multi-system and not fully resolved.
Pharmacokinetic data are limited. Like most short peptides, Selank is vulnerable to plasma and tissue peptidases, and its measured half-life in circulation is short, on a minutes scale. The Pro-Gly-Pro tail slows this degradation but does not eliminate it. Intranasal administration is the route described in most reports, with absorption through the nasal mucosa and a hypothesized path into the central nervous system that avoids the blood-brain barrier. Direct measurements of human brain exposure are unavailable, so distribution claims rest on inference from animal work.
Clinical evidence comes mainly from small studies conducted in Russia, several of which were open-label or lacked robust blinding. Reported outcomes include lower anxiety scores, changes in attention measures, and effects on asthenic states following illness. Sample sizes are typically in the tens of participants, and independent replication outside the region is scarce. Reviews published in English generally note the limited methodological quality of the underlying trials. Whether the compound produces clinically meaningful effects under rigorous conditions remains unresolved.
Animal studies have examined behaviour in tests of anxiety, memory retention and stress response, and several report changes in neurotrophic or neurotransmitter-related markers. The human evidence base is much smaller, consisting mainly of short trials conducted in Russia with limited reporting in English-language journals. Sample sizes are modest and outcome measures vary between studies, so the findings are best described as preliminary. Independent replication under modern trial standards has not been widely reported.
Outside its country of origin the compound is generally handled as a research chemical rather than an approved medicine. No regulatory approval from the United States Food and Drug Administration or the European Medicines Agency has been granted for human use. Identity and purity are normally checked by reverse-phase high-performance liquid chromatography, with mass spectrometry used to confirm the molecular mass. Lyophilised material is stored cold and desiccated, and repeated freeze-thaw cycles are avoided.
Published work on this peptide almost always uses intranasal delivery, with drops or a spray applied to the nasal mucosa. Some animal experiments have used subcutaneous or intraperitoneal injection, and a smaller number have compared routes directly. Oral administration is not a focus of the literature, because short peptides of this size are broken down by digestive enzymes and cross intestinal barriers poorly. How much of an intranasal dose reaches the bloodstream intact in humans remains an open question.
Maggot debridement therapy (also known as MDT, larval therapy, or simply maggot therapy) is a type of biotherapy involving the introduction of live, disinfected maggots into non-healing skin and soft-tissue wounds of a human or other animal for the purpose of cleaning out the necrotic tissue within a wound (debridement), and disinfection. There is evidence that maggot therapy may help with wound healing.
Because of the short duration of elagolix in the body, the activation of the GnRHR by GnRH is not fully blocked throughout the day with once-daily administration of elagolix. As a result, gonadotropin and sex hormone levels are only partially suppressed when elagolix is taken once per day. In addition, the degree of suppression can be dose-dependently adjusted as needed, for instance with higher-dose twice-daily administration to achieve greater hormonal suppression. Because of its short duration in the body, the effects of elagolix are rapidly reversible upon discontinuation. In addition, due to its partial and incomplete suppression of estradiol levels, the side effects of elagolix, such as hot flashes and decreased BMD, are lower than with first-generation GnRH modulators.
Over its history as a food, the main uses of honey are in cooking, baking, desserts, as a spread on bread, as an addition to various beverages such as tea, and as a sweetener in some commercial beverages. Due to its energy density, honey is an important food for virtually all hunter-gatherer cultures in warm climates, with the Hadza people ranking honey as their favorite food. Honey hunters in Africa have a mutualistic relationship with certain species of honeyguide birds.
Sources: en.wikipedia.org
A third, only marginally related concept was proposed in 1923 by Gilbert N. Lewis, which includes reactions with acid–base characteristics that do not involve a proton transfer. A Lewis acid is a species that accepts a pair of electrons from another species; in other words, it is an electron pair acceptor. Brønsted acid–base reactions are proton transfer reactions while Lewis acid–base reactions are electron pair transfers. Many Lewis acids are not Brønsted–Lowry acids. Contrast how the following reactions are described in terms of acid–base chemistry:
α-neptunium takes on an orthorhombic structure, resembling a highly distorted body-centered cubic structure. Each neptunium atom is coordinated to four others and the Np–Np bond lengths are 260 pm. It is the densest of all the actinides and the fifth-densest of all naturally occurring elements, behind only rhenium, platinum, iridium, and osmium. α-neptunium has semimetallic properties, such as strong covalent bonding and a high electrical resistivity, and its metallic physical properties are closer to those of the metalloids than the true metals. Some allotropes of the other actinides also exhibit similar behaviour, though to a lesser degree. The densities of different isotopes of neptunium in the alpha phase are expected to be observably different: α-235Np should have density 20.303 g/cm3; α-236Np, density 20.389 g/cm3; α-237Np, density 20.476 g/cm3. β-neptunium takes on a distorted tetragonal close-packed structure. Four atoms of neptunium make up a unit cell, and the Np–Np bond lengths are 276 pm. γ-neptunium has a body-centered cubic structure and has Np–Np bond length of 297 pm. The γ form becomes less stable with increased pressure, though the melting point of neptunium also increases with pressure. The β-Np/γ-Np/liquid triple point occurs at 725 °C and 3200 MPa.
The Li-ion battery recycling rate is often misconstrued to be 5%, in reality, insufficient research exists to determine the exact figure. The European Union estimates 49% of portable batteries sold were collected for recycling in 2023, whilst the UK estimates 45% as of 2026. New EU legislation requires 70% of collected Li-ion battery material to be recovered through recycling by 2031, which must include recovery rates of 80% for lithium and 95% for cobalt, nickel, and manganese; however, no recycled lithium has re-entered the EU as of 2023. These measures aim to aid sustainability efforts and reduce pressure on raw material extraction, as demand for lithium and cobalt is expected to increase 8-fold by 2040, far exceeding current production capabilities. Most research focuses on the recovery of active materials, especially lithium which is a critical raw material; however, through advanced recycling techniques and more sustainable design considerations, electrolytes, binders, and separators can also be recycled. Recycling is a multi-step process, starting with the storage of batteries before disposal, followed by manual testing, disassembling, and finally the chemical separation of battery components. Re-use of the battery is preferred over complete recycling as there is less embodied energy in the process. As these batteries are a lot more reactive than classical vehicle waste like tire rubber, there are significant risks to stockpiling used batteries.
=== Objectives === Recovery point objective (RPO): The point in time that the restarted infrastructure will reflect, expressed as "the maximum targeted period in which data (transactions) might be lost from an IT service due to a major incident". Essentially, this is the roll-back that will be experienced as a result of the recovery. The most desirable RPO would be the point just prior to the data loss event. Making a more recent recovery point achievable requires increasing the frequency of synchronization between the source data and the backup repository. Recovery time objective (RTO): The amount of time elapsed between disaster and restoration of business functions. Data security: In addition to preserving access to data for its owners, data must be restricted from unauthorized access. Backups must be performed in a manner that does not compromise the original owner's undertaking. This can be achieved with data encryption and proper media handling policies. Data retention period: Regulations and policy can lead to situations where backups are expected to be retained for a particular period, but not any further. Retaining backups after this period can lead to unwanted liability and sub-optimal use of storage media. Checksum or hash function validation: Applications that back up to tape archive files need this option to verify that the data was accurately copied.
Sources: en.wikipedia.org
== External links == "Formylpeptide Receptors: FPRL1". IUPHAR Database of Receptors and Ion Channels. International Union of Basic and Clinical Pharmacology. This article incorporates text from the United States National Library of Medicine, which is in the public domain.
D-amino-acid transaminase (EC 2.6.1.21) is an enzyme originally characterised from bacteria that catalyzes several reversible chemical reactions that interconvert specific D-amino acids and α-ketoglutaric acid with the corresponding α-keto acid and D-glutamic acid. For example, it can use D-alanine as a substrate:
In November 2022, Cerebras announced a partnership with Cirrascale Cloud Services to provide a flat-rate "pay-per-model" compute time for its Cerebras AI Model Studio. In November 2022, the National Energy Technology Laboratory (NETL) set milestones using Cerebras products. In November 2022, Argonne National Laboratory won the 2022 Gordon Bell Special Prize for COVID-19 research by using the CS-2 as well as products from Nvidia and Hewlett-Packard to transform large language models to analyze and predict variants of SARS-CoV-2. In July 2023, G42 agreed to pay around $100 million to purchase the first of potentially nine supercomputers from Cerebras. The first computer, Condor Galaxy 1 (CG-1), is capable of 4 quintillion floating-point operations per second (4 exaflops) of compute and contains 54 million cores. In November 2023, the second computer, the Condor Galaxy 2 (CG-2), was announced, with similar specifications as the CG-1. In March 2024, the companies broke ground on the Condor Galaxy 3 (CG-3), which can reach 8 exaFLOPs of performance and contains 58 million AI-optimized cores. In August 2023, Cerebras, the Mohamed bin Zayed University of Artificial Intelligence, and G42 subsidiary Inception launched Jais, a large language model. In March 2024, Cerebras introduced Wafer Scale Engine (WSE-3) architecture, a 5nm-based chip hosting 4 trillion transistors and 900,000 AI-optimized cores, and the basis for the CS-3. It has twice the performance of CS-2. The CS-3 was named to the list of the "best inventions of 2024" by Time.
Sources: en.wikipedia.org
Reports describe modulation of GABA signalling, changes in monoamine turnover and effects on neurotrophic factor expression. These observations come mainly from animal and cell studies. A single unifying mechanism has not been demonstrated.
The peptide enters plasma rapidly and is broken down by ordinary proteases into amino acids and shorter fragments. Reported half-lives are short. Whether meaningful amounts of the intact molecule reach the brain is an open question.
Most clinical reports are small, published in Russian and not independently replicated. English-language reviews highlight the absence of large randomised trials. Conclusions about efficacy should be treated as provisional.
Selank is a synthetic heptapeptide designed as a stabilized analog of the natural tetrapeptide tuftsin. It has been investigated mainly for anxiolytic and cognitive effects. It is not an approved pharmaceutical in most countries.