New biomaterial regrows damaged cartilage in joints
Northwestern University scientists have developed a new bioactive material that successfully regenerated high-quality cartilage in the knee joints of a large-animal model.
Aug 5, 2024
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Northwestern University scientists have developed a new bioactive material that successfully regenerated high-quality cartilage in the knee joints of a large-animal model.
Aug 5, 2024
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Researchers at UT Southwestern Medical Center have discovered that a diet free of the amino acid tryptophan can effectively halt the growth of liver cancer in mice. Their findings, published in Nature Communications, offer ...
Aug 1, 2024
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A new paper published in the journal Proceedings of the National Academy of Sciences shows how an amino acid may hold the secrets of oral cancers.
Jul 30, 2024
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Seaweed, the colorful macroalgae that grows in the ocean, is a food source for marine life and humans. Each type of seaweed has a unique set of nutrients and can boost vitamin and mineral intake if eaten regularly.
Aug 3, 2024
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A new study from the University of Michigan Health Rogel Cancer Center finds that giving a fatty acid inhibitor alongside chemotherapy could improve the treatment efficacy for patients with brain metastases from triple negative ...
Jul 30, 2024
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In a study published in Life Science Alliance, Texas A&M AgriLife Research scientists found that decreasing folate intake can support healthier metabolisms in aging animal models, challenging the conventional belief that ...
Aug 2, 2024
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Recent research has shown that our diet plays a crucial role in maintaining not just our physical well-being, but also our brain health. A diet high in sugars and processed foods can weaken brain function and negatively impact ...
Aug 5, 2024
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Don't use a chemical peel to help rejuvenate your skin unless it's done under the supervision of a trained professional, the U.S. Food and Drug Administration has advised.
Aug 1, 2024
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An acid (from the Latin acidus/acēre meaning sour) is a substance which reacts with a base. Commonly, acids can be identified as tasting sour, reacting with metals such as calcium, and bases like sodium carbonate. Aqueous acids have a pH of less than 7, where an acid of lower pH is typically stronger, and turn blue litmus paper red. Chemicals or substances having the property of an acid are said to be acidic.
Common examples of acids include acetic acid (in vinegar), sulfuric acid (used in car batteries), and tartaric acid (used in baking). As these three examples show, acids can be solutions, liquids, or solids. Gases such as hydrogen chloride can be acids as well. Strong acids and some concentrated weak acids are corrosive, but there are exceptions such as carboranes and boric acid.
There are three common definitions for acids: the Arrhenius definition, the Brønsted-Lowry definition, and the Lewis definition. The Arrhenius definition states that acids are substances which increase the concentration of hydronium ions (H3O+) in solution. The Brønsted-Lowry definition is an expansion: an acid is a substance which can act as a proton donor. Most acids encountered in everyday life are aqueous solutions, or can be dissolved in water, and these two definitions are most relevant. The reason why pHs of acids are less than 7 is that the concentration of hydronium ions is greater than 10−7 moles per liter. Since pH is defined as the negative logarithm of the concentration of hydronium ions, acids thus have pHs of less than 7. By the Brønsted-Lowry definition, any compound which can easily be deprotonated can be considered an acid. Examples include alcohols and amines which contain O-H or N-H fragments.
In chemistry, the Lewis definition of acidity is frequently encountered. Lewis acids are electron-pair acceptors. Examples of Lewis acids include all metal cations, and electron-deficient molecules such as boron trifluoride and aluminium trichloride. Hydronium ions are acids according to all three definitions. Interestingly, although alcohols and amines can be Brønsted-Lowry acids as mentioned above, they can also function as Lewis bases due to the lone pairs of electrons on their oxygen and nitrogen atoms.
This text uses material from Wikipedia, licensed under CC BY-SA