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Our Radiation Environment
Published in T. D. Luckey, Radiation Hormesis, 2020
The most common chemical reaction following the absorption of ionizing radiation by water is the formation of a cascade of free radicals which avidly seek any possible means to form stable complexes with neighboring molecules. The most reactive species in this drama are the hydroxyl ion and the hydrated electron. Many strange and unusual molecules are formed when these two come to rest. A concise explanation of different types of radiations, their energy transfer processes, and the formation of free radicals was summarized in BEIR V.58 An electron is stripped from the water molecule to produce a positively charged water molecule, H2O+, plus an electron which immediately attaches to another water molecule to form a “hydrated electron”. This free electron reacts with nearby molecules to produce strange and sometimes biologically important compounds. The ionized water and normal water react to produce the hydronium ion and the hydroxyl radical:
Site-Specific Chemical Modification of Proteins
Published in Roger L. Lundblad, Chemical Reagents for Protein Modification, 2020
Before going further it might be useful to define some terms that we will be using. When most of us think of acids we tend to think of substances such as hydrochloric acid, sulfuric acid, and acetic acid, substances which can donate protons in aqueous solution to form hydronium ions (H3O+). Likewise a base is most usually considered to be a substance (e.g., hydroxide ion — OH−) which can accept protons. In other words, by this definition a base possesses an unshared electron pair with which it can attract and hold a proton. This is the classical Bronsted definition of acids and bases. Organic chemists find it more useful to use the Lewis definition of acids and bases. Using this definition, an acid is a substance that can form a covalent bond by accepting an electron pair and a base has an unshared electron pair. Taking this a step further then, Lewis acids are electrophilic while Lewis bases are nucleophilic.
Alternate Methods for Visualizing and Constructing
Published in Patrick E. McMahon, Rosemary F. McMahon, Bohdan B. Khomtchouk, Survival Guide to General Chemistry, 2019
Patrick E. McMahon, Rosemary F. McMahon, Bohdan B. Khomtchouk
Example: Show the formation of a coordinate covalent bond between H+ and a water molecule to for the hydronium ion (H3O+).
The Warburg hypothesis and weak ELF biointeractions
Published in Electromagnetic Biology and Medicine, 2020
Among the more recent ELF experimental studies are those initiated by Grimaldi (D’Emilia et al. 2015) involving water structure. Exposing water to ICR field combinations tuned to the hydronium ion (H3O+) results in a sharply reduced pH, or equivalently, in an increase in uncoupled protons. Additionally, a series of experiments in Novikov’s laboratory (Novikov and Fesenko 2001) have probed the use of ICR signals in teasing apart various metabolic reactions. Especially interesting is that this laboratory has found it particularly useful to simultaneously apply different ICR frequencies corresponding to more than one cation by simply applying the electronic sum of the various signals. Presumably the system to which this summed signal is being applied is “smart enough” to respond to each of the ICR conditions that comprise the electronic sum. In so doing it is hoped that the system under study will correspond more faithfully to real-world biochemical changes, which occur either simultaneously or in rapid succession. In a loose comparison, the Novikov application of several ICR frequencies at once might be considered equivalent to taking a diverse group of pharmaceutically prescribed pills together.
The role of the clinical laboratory in diagnosing acid–base disorders
Published in Critical Reviews in Clinical Laboratory Sciences, 2019
Body fluids may be considered as dilute aqueous solutions. In pure water, there is a small dissociation expressed in the reaction: H2O ↔ H++OH−; in fact, it is hydronium instead of H+: 2H2O ↔ H3O++OH−. The H2O concentration in pure water is 55 mmol/L, and [H+] and [OH−] 10−7 or less [1,15]. The effect of temperature on pH of blood was established in 1948: 0.015 units decrease per degree Celsius increase [16]. In a clinical setting, the potential effect of pre-analytical temperature on sample handling and storage is probably low. Sample storage at 0° for up to 60 min showed no effect on pH whereas sample storage at 22° showed significant decrease after 30 min in one study [17].
Effects of low-level combined static and weak low-frequency alternating magnetic fields on cytokine production and tumor development in mice
Published in Electromagnetic Biology and Medicine, 2019
Elena G. Novoselova, Vadim V. Novikov, Sergey M. Lunin, Olga V. Glushkova, Tatyana V. Novoselova, Svetlana B. Parfenyuk, Sergey V. Novoselov, Maxim O. Khrenov, Evgeny E. Fesenko
Obviously, the formal correspondence to the cyclotron frequencies of the ionic forms of the molecules of free amino acids in the solution does not allow us to make conclusions about the primary mechanism of cyclotron resonance under in vivo conditions. It should be noted that these were the frequencies that produced physical effects at very small intensities (tens of nT) of the alternating magnetic field in particular, the rapid changes in ionic electrolytic current described in the earliest (Novikov, 1996; Novikov and Karnaukhov, 1997; Novikov and Zhadin, 1994; Zhadin et al., 1998) and subsequent studies (Alberto et al., 2008; Comisso et al., 2006; Del Giudice et al., 2002; Giuliani et al., 2008; Pazur, 2004). In addition, it was recently reported that weak-field (50 nT) hydronium ion cyclotron resonance at the field combination (7.84 Hz, 7.5 µT) markedly changed water structure (D’Emilia et al., 2017). This model may also explain the numerous previously observed cyclotron resonance biological couplings for cations other than hydronium by merely substituting hydrogen-bonded versions of these for hydronium in the tetrahedral structure (Liboff et al., 2017). The authors hypothesize “that the effectiveness of resonance stimulation in biological systems can be explained assuming that the radiation associated with this process may play a role in the interactions at the interface between water and living matter” (Liboff et al., 2017).When using a constant magnetic field intensity of 65 μT, the six-frequency signal was compared to the ten-frequency signal, including four additional voluntary chosen frequencies (5.57; 5.73; 6.44, and 7.60 Hz) from the testing range. Furthermore, a two-frequency signal (3.7 and 4.4 Hz) from the testing range was used in several experiments.