collagen comes up often in conversation and rarely with the context attached. Here we lay out the basics in order, then work through the practical considerations.
Updated 2026-01-22. Numbers and descriptions here follow the published literature rather than marketing material.
Collagen peptides are short chains of amino acids produced by hydrolyzing collagen extracted from animal connective tissues. The hydrolysis process breaks the native triple helix into smaller fragments, typically through enzymatic or chemical treatment. Sources include bovine hide, porcine skin, fish scales, and poultry cartilage; the resulting material is water-soluble and can be dried into a powder. Commercial production often uses controlled temperature and pH to achieve a consistent average molecular mass. The degree of hydrolysis influences the peptide size distribution and functional properties.
The amino acid profile of collagen peptides is distinctive, with glycine, proline, and hydroxyproline together accounting for a large fraction of residues. Glycine appears at nearly every third position in the original collagen sequence, a pattern partly retained in shorter peptides. Hydroxyproline is formed by post-translational modification of proline and serves as a marker for collagen-derived material. Unlike many proteins, collagen peptides contain little or no tryptophan and low levels of cysteine.
Most commercial collagen peptides derive from bovine hide, porcine skin, fish skin, or poultry cartilage, with fish sources often having lower thermal stability. Their amino acid profile is distinctive: glycine appears at roughly every third residue in the parent collagen triple helix, and proline and hydroxyproline are abundant. Collagen itself lacks tryptophan and is low in several essential amino acids, so collagen peptides are not a complete protein source. Source tissue and processing can influence peptide length, amino acid composition, color, odor, and mineral content.
Hydrolysis conditions determine the peptide size profile, which in turn affects solubility, viscosity, taste, and behavior in formulations. Products may contain free amino acids, di- and tripeptides, and larger fragments up to tens of kilodaltons. Average molecular weight is often reported, but the distribution is more informative because two materials with the same average can differ in peptide profile. Ultrafiltration, spray drying, and ion exchange may be used to standardize the final powder. The relationship between specific peptide sequences and measured effects remains an active area of study.
Collagen peptides are short protein fragments produced by breaking down native collagen, the main structural protein in skin, bone, tendon, and cartilage. The term usually refers to hydrolyzed collagen, a mixture of peptides rather than a single defined molecule. Enzymatic or chemical hydrolysis cleaves peptide bonds, lowering molecular weight and improving water solubility relative to intact collagen. Commercial material is commonly described by average molecular weight, source tissue, and extent of hydrolysis rather than by a unique sequence.
| Property | Value | Notes |
|---|---|---|
| Appearance | White to off-white powder | May vary with source and processing |
| Solubility | Soluble in water | Forms clear to slightly hazy solutions |
| Typical molecular mass | 2,000–10,000 Da | Depends on degree of hydrolysis |
| Common synonyms | Collagen hydrolysate; hydrolyzed collagen | Not identical to gelatin |
| Primary amino acids | Glycine, proline, hydroxyproline | Together often exceed 50% of residues |
. These are the number of people in the susceptible, infected and removed categories at time equals zero. If the SIR model is assumed to hold at all times, these initial conditions are not independent. Subsequently, the flow model updates the three variables for every time point with set values for
=== January === 1 January – A driver runs over two police officers on a foot patrol in Nelson, killing one and injuring the other. A 32-year-old man is arrested. 3 January: A 32-year old man is charged with the murder of Nelson police officer Senior Sergeant Lyn Fleming. Biosecurity New Zealand launches a major biosecurity operation after an oriental fruit fly is detected in South Auckland. Thousands attend a vigil in Nelson for slain police officer Lyn Fleming. Air New Zealand flight NZ677 from Auckland to Dunedin is cancelled due to a phone threat, affecting 170 passengers. 4 January – Interislander and Bluebridge cancel a total of seven ferry crossings in response to rough weather conditions in the Cook Strait. 5 January – Interislander and Bluebridge cancel five ferry crossings in response to continuing rough weather in the Cook Strait. 6 January: The Desert Road closes for two months of repairs. Interislander and Bluebridge suspend ferry crossings due to rough weather in the Cook Strait. 8 January – Over 2,070 customers in the Kaipara District experience internet outages after a digger damages the main fibre optic cable between Whangārei and Dargaville. 9 January: In response to significant public interest, New Zealand Parliament's justice select committee extends the submission deadline for the Treaty Principles Bill to 1pm on 14 January. A fire engulfs 20 hectares (49 acres) of scrubland in Whangārei, leading to the evacuation of two houses.
Free nerve ending A type of unencapsulated nerve ending that detects pain, temperature, and crude touch. These are the most common type of cutaneous receptors. Frontal lobe A region of the cerebral cortex involved in decision-making, planning, motor function, problem-solving, and aspects of personality. Located at the front of each cerebral hemisphere. Frontal eye fields A region in the frontal lobe involved in voluntary eye movements and visual attention. It plays a role in saccadic control and visual tracking. Functional connectivity A measure of how different brain regions interact during rest or tasks, often assessed using fMRI or EEG by examining correlations in activity over time. Functional magnetic resonance imaging (fMRI) A neuroimaging technique that measures brain activity by detecting changes in blood oxygenation (BOLD signal). It is used to study brain function in real time. Fusiform gyrus A brain region located in the temporal and occipital lobes involved in high-level visual processing, including facial recognition and object categorization. Fusiform face area (FFA) A specialized part of the fusiform gyrus that responds selectively to faces. It is often studied in the context of prosopagnosia (face blindness) and visual expertise.
Anhalt is now part of the state of Saxony-Anhalt. Baden is now part of Baden-Württemberg. Braunschweig is now part of Lower Saxony. Lippe is now part of North Rhine-Westphalia. Lübeck is now part of Schleswig-Holstein. Mecklenburg-Schwerin and Mecklenburg-Strelitz are now parts of Mecklenburg-Vorpommern. Oldenburg is now part of Lower Saxony, with its former exclaves now belonging to their neighbouring states of Rhineland-Palatinate and Schleswig-Holstein. Prussia was divided among the states of Berlin, Brandenburg, Lower Saxony, North Rhine-Westphalia, Rhineland-Palatinate, Saxony-Anhalt and Schleswig-Holstein. The erstwhile Prussian provinces of Brandenburg, Saxony, Schleswig-Holstein and Hanover formed the core of the states of Brandenburg, Saxony-Anhalt, Schleswig-Holstein and Lower Saxony, respectively. The Prussian provinces of Westphalia and Rhineland contributed most territory to the state of North Rhine-Westphalia, and Rhineland province contributed about half of the territory of the state of Rhineland Palatinate. Most of the Prussian province of Hesse-Nassau was merged with the existing state of Hesse. Some territories bordering other states were annexed to the bordering state. Also, Prussia had exclaves that were surrounded by other states. These became part of their surrounding states. All states, except Bavaria, now have territory of the former Free State of Prussia. Other former Prussian territories lying east of the rivers Neisse and Oder were lost in 1945 and are now part of Poland or Russia.
Sources: en.wikipedia.org
=== Psychiatric disorders === Serotonin plays an important role in numerous physiological conditions. 5-HT2 receptor antagonists have long been known, but recently 5-HT2 receptor agonists are becoming promising agents in the development for new antipsychotic drugs. Historically, most pharmacological research on antipsychotic drugs have concentrated on the 5-HT2A receptor subtype. However, recent studies show that agonist activity on 5-HT2A receptors can cause hallucination. Comparison of SSRIs and the 5-HT2C receptor agonists showed that the agonists decreased immobility time and increased swimming time in the FST (forced swim test) in rats in a manner comparable to SSRIs. In the 1990s 5-HT2C receptors have received more attention as many studies have shown that selective 5-HT2C receptor agonists may be more suited in the treatment for psychotic indications. A 5-HT2C agonist may be expected to reduce positive symptoms of schizophrenia by reducing dopamine release in the mesolimbic dopamine pathway. Vabicaserin (SCA-136) is a 5-HT2C agonist that has shown promise in preliminary testing for the treatment of schizophrenia.
Since the missile approached the target as it climbed, each of these intersections would be closer to the target. Taking several of these, in turn, the trajectory of the missile could be determined to some degree of accuracy, and air raid warnings sent to likely areas. Success in this task was aided by the missile fuselage profile, which acted as an excellent quarter-wave reflector for 12 m band HF radar. RAF Fighter Command was also informed of the launch in an effort to attack the sites. However, the German launch convoys were motorized, well camouflaged and highly mobile, making them extremely difficult to find and attack. The only known claim was made when Supermarine Spitfire pilots of No. 602 Squadron RAF squadron came across a V-2 rising from a wooded area, allowing a quick shot of unknown result.
Nalin Chandra Wickramasinghe (born 20 January 1939) is a Sri Lankan-born British mathematician and astronomer. His research interests include the interstellar medium, infrared astronomy, light scattering theory, applications of solid-state physics to astronomy, the early Solar System, comets, astrochemistry, the origin of life and astrobiology. A student and collaborator of Fred Hoyle, the pair worked jointly for over 40 years as the most famous proponents of a non-mainstream version of panspermia, the proposal that life was seeded (or continues to be seeded) on Earth through space-based processes. In 1974 they proposed that some dust in interstellar space matched the spectral characteristics of freeze-dried bacteria, which was largely ignored at its publishing while the ubiquity of polycyclic aromatic hydrocarbons explains the apparent match. Wickramasinghe has advanced numerous fringe claims, including the argument that various outbreaks of illnesses on Earth are of extraterrestrial origins, including the 1918 flu pandemic and certain outbreaks of polio and mad cow disease. For the 1918 flu pandemic they proposed that cometary dust brought the virus to Earth simultaneously at multiple locations—a view dismissed by experts on this pandemic. Claims connecting terrestrial disease and extraterrestrial pathogens have been rejected by the scientific community. Wickramasinghe has written more than 40 books about astrophysics and related topics; he has made appearances on radio, television and film, and he writes online blogs and articles.
==== Medical records ==== Police searches of Letby's home recovered sensitive medical documents, including nursing handover sheets, resuscitation records and blood‑gas printouts. A total of 257 sheets were found, 21 of which related to infants she was later accused of harming. Letby told the court that she often forgot to remove paperwork from her pockets after shifts and described herself as someone who "collect[ed] paper". She also said she had been unable to destroy the documents, although a paper shredder was found in her home.
Norepinephrine is the main neurotransmitter used by the sympathetic nervous system, which consists of about two dozen sympathetic chain ganglia located next to the spinal cord, plus a set of prevertebral ganglia located in the chest and abdomen. These sympathetic ganglia are connected to numerous organs, including the eyes, salivary glands, heart, lungs, liver, gallbladder, stomach, intestines, kidneys, urinary bladder, reproductive organs, muscles, skin, and adrenal glands. Sympathetic activation of the adrenal glands causes the part called the adrenal medulla to release norepinephrine (as well as epinephrine) into the bloodstream, from which, functioning as a hormone, it gains further access to a wide variety of tissues. Broadly speaking, the effect of norepinephrine on each target organ is to modify its state in a way that makes it more conducive to active body movement, often at a cost of increased energy use and increased wear and tear. This can be contrasted with the acetylcholine-mediated effects of the parasympathetic nervous system, which modifies most of the same organs into a state more conducive to rest, recovery, and digestion of food, and usually less costly in terms of energy expenditure. The sympathetic effects of norepinephrine include:
Sources: en.wikipedia.org
=== Other Latin American and Caribbean === Prime Minister of Trinidad and Tobago Kamla Persad-Bissessar praised the US attack and encouraged more operations against drug traffickers, saying: "The pain and suffering the cartels have inflicted on our nation is immense. I have no sympathy for traffickers; the US military should kill them all violently." Raising concerns that the bodies washing ashore won't be investigated, and placing Trinidad and Tobago at odds with other CARICOM members, she supports the strikes, saying: "I much prefer seeing drug and gun traffickers blown to pieces than seeing hundreds of our citizens murdered each year because of drug-fueled gang violence." The family of one of the Trinidad missing said due process was not given and accused Trump of "killing poor people". Colombian president Gustavo Petro said that attacking the boat occupants in drug interdictions rather than capturing them amounted to murder. On 11 November, Petro announced he would suspend sharing of intelligence with the US while strikes on vessels continued; Efecto Cocuyo reported that Colombian Ministers of Defense and of the Interior stated on 13 November that Colombia would continue cooperating with the US. When asked whose side he was on, Brazilian president Luiz Inácio Lula da Silva said he was on the side of peace, favored negotiations, and that US forces in the Caribbean had become a source of tension.
In a Kendrick mass analysis, the Kendrick mass defect is plotted as function of nominal Kendrick mass for ions observed in a mass spectrum. Ions of the same family, for example the members of an alkylation series, have the same Kendrick mass defect but different nominal Kendrick mass and are positioned along a horizontal line on the plot. If the composition of one ion in the family can be determined, the composition of the other ions can be inferred. Horizontal lines of different Kendrick mass defect correspond to ions of different composition, for example degree of saturation or heteroatom content. A Kendrick mass analysis is often used in conjunction with a Van Krevelen diagram, a two- or three- dimensional graphical analysis in which the elemental composition of the compounds are plotted according to the atomic ratios H/C, O/C, or N/C.
== Company history == The company traces its roots to William Lines, Inc., which began as a shipping business founded by William Chiongbian on December 13, 1945, in Cebu City. He named one of its first vessels, the MV Victoriano, after his father; the ship made its maiden voyage serving the routes from Cebu to Tagbilaran, Bohol, and Siquijor, then to Plaridel and Ozamiz. The company was later incorporated on May 26, 1949. From the 1970s to the 1990s, the company introduced several flagship vessels, including MV Cebu City (1972), MV Doña Virginia (1980), and MV Sugbu (1989), and grew to become one of the largest shipping companies in the Philippines during that period. In the 1990s, William Lines introduced the Mabuhay Series, comprising the company's largest and most luxurious vessels, designed to compete with rival fleets, including Sulpicio Lines and Aboitiz's SuperFerry ships. The first ship of the series, the Wilines Mabuhay 1, was acquired from Japan and was part of the well-known Sunflower series of vessels. Subsequently, William Lines added more ships to the Mabuhay Series, including Mabuhay 2, 3, 5, and 6. In December 1995, William Lines acquired the assets of Gothong Lines and Aboitiz Shipping Corporation through a ₱5.68 billion share-swap deal, issuing new William Lines shares to the two companies in exchange for their shipping properties. The merger consolidated the operations of the three shipping firms, forming William, Gothong and Aboitiz Inc. (WG&A), which became the largest domestic shipping company in the Philippines.
Semen can be used successfully almost indefinitely after cryopreservation in a sperm bank. The longest reported successful storage is 22 years. It can be used for sperm donation where the recipient wants the treatment in a different time or place or as a means of preserving fertility for men undergoing vasectomy or treatments that may compromise their fertility, such as chemotherapy, radiation therapy or surgery.
However, some in the Japanese archaeological community remain skeptical about the presence of cattle in Japan during the Yayoi period, and there is a persistent view that they were brought to Japan from the Korean peninsula by the toraijin, a group of people who came to Japan in the mid-5th century during the Kofun period. At the Nango-Ōhigashi site in Gose City, Nara Prefecture, excavations revealed cow bones believed to date back to the 5th century. At the Funamiya Kofun Tumulus (late 5th century) in Asago City, Hyōgo Prefecture, pieces of a cow-shaped haniwa (clay figurine), believed to be the oldest in Japan, have been excavated. In addition, a cow-shaped haniwa was excavated from the Hashida No. 1 Tumulus in Tawaramoto Town, Shiki-gun, Nara Prefecture in the first half of the 6th century, and was designated as an Important Cultural Property of Japan in 1958. On the other hand, recent genetic studies have shown that Wagyu and Korean cattle (Hanwoo and others) differ greatly in their genetic information. Livestock cattle are divided into two major lineages: northern lineage cattle (Bos taurus) and Indian lineage cattle (Bos indicus), and both Wagyu and Korean cattle belong to the northern lineage and do not contain Indian lineage such as Zebu cattle. However, in terms of mitochondrial DNA haplogroups, haplogroup T4 (East Asian type) is predominant in the Wagyu (Japanese Black) at about 65%, while haplogroup T3 (European type) is predominant in Korean cattle at 66–83%.
Sources: en.wikipedia.org
Gelatin is partially hydrolyzed collagen that forms a gel in water, while collagen peptides are more extensively hydrolyzed into shorter chains that remain soluble and do not gel at typical concentrations. Both derive from animal connective tissue, but their functional properties differ.
No, native collagen has a triple-helical structure and is insoluble in water, whereas hydrolysis disrupts this structure to yield shorter peptide chains. The resulting peptides are water-soluble and have different physical behavior.
Bovine and porcine skin and bone are common sources, as are fish skin and scales. Each source yields a distinct amino acid profile, particularly in hydroxyproline content, which can affect analytical results.
Collagen peptides are water-soluble fragments formed when collagen is hydrolyzed into shorter chains. They are sold as powders or liquids and are distinct from intact collagen and from gelatin, though all three share a similar amino acid composition.