Common gastrointestinal investigations and psychological concerns
Simon R. Knowles, Laurie Keefer, Antonina A. Mikocka-Walus in Psychogastroenterology for Adults, 2019
pH (acid) monitoring with a thin, flexible tube in the oesophagus and stomach measures the amount and duration of acid exposure. The higher the acidity value, the lower the pH values. pH monitoring is considered the gold standard for diagnosing reflux disease. To perform the test, a technician gently inserts a small, flexible pH probe through the nose, into the oesophagus, with pH sensors sitting in the stomach and just above the lower oesophageal sphincter (near the junction between the oesophagus and stomach). The probe is left there for 24 hours, and patients are asked to record their symptoms during that time and also to log when they eat, sleep, drink, etc., so symptoms and other events can be matched with episodes of oesophageal acidification to generate a “symptom association probability” score. At the end of the test, the probe is removed and the information from the monitoring device is collected for interpretation. Matching symptoms and acidity helps determine whether reflux is the cause for patients’ symptoms or not. Preparation for the test is similar to that of oesophageal manometry and often carried out on the same day. Medications that reduce acid secretion generally need to be stopped three days before the test.
Effects of Food Processing, Storage, and Cooking on Nutrients in Plant-Based Foods
Nicole M. Farmer, Andres Victor Ardisson Korat in Cooking for Health and Disease Prevention, 2022
When using a wet-cooking method, it is important to consider the type of vegetable to decide whether to cook covered or uncovered. White vegetables such as onions, cauliflower, and potatoes contain pigments called flavones, and these pigments retain their color in acidic conditions and may turn yellow in alkaline water. Thus, preserving natural acids or adding acid to white vegetables is helpful. White vegetables may be cooked with the lid on to keep some of the natural acids in the cooking water. Alternatively, a very small amount of acid, such as vinegar or lemon juice, may be added. Cook for a short period of time, and cool quickly to prevent white pigments from turning gray.
Biochemical Contributors to Exercise Fatigue
Peter M. Tiidus, Rebecca E. K. MacPherson, Paul J. LeBlanc, Andrea R. Josse in The Routledge Handbook on Biochemistry of Exercise, 2020
Anaerobic metabolism results in accumulation of lactate ions and H+, mainly due to glycogen breakdown, and of creatine ions and Pi, due to PCr breakdown. Lactate and creatine ions have no major impact on force production (54, 68), whereas increased cytoplasmic concentrations of both H+ and Pi can inhibit myofibrillar contractile function. Traditionally, the acidosis accompanying “lactic acid” accumulation was considered the major cause of acute fatigue, but this viewpoint is challenged by many studies where acidosis has been shown to be of limited importance (10, 22, 61, 62, 93). Instead increased Pi is proposed to be the dominant cause of the impaired myofibrillar force production during acute fatigue (1, 17, 90). However, this topic remains controversial, with a major unresolved issue being whether or not the force-reducing effects of elevated Pi in fatigue are amplified by the concomitant acidosis (28, 86).
The relationship between the Hammett acidity and the decomposition of cefotaxime sodium in the solid state
Published in Drug Development and Industrial Pharmacy, 2020
Bashar M. Altaani, Khouloud A. Alkhamis, Shaima’a Abu Baker, Razan Haddad
In dilute solutions, the acidity is described by the regular pH scale. The use of this scale in highly concentrated solutions is not valid. Hammett proposed an acidity function that can be used in highly concentrated solutions. This function is based on the use of indicator molecules. The Hammett function [19–20] for acidic indicator is shown below: H is the proton activity, f is the indicator activity coefficient and A– and HA are the deprotonated and protonated indicator species respectively. The Hammett acidity function is dependent on the proton activity of the system and on the medium polarity which is expressed in the aforementioned equation by the ratio of the activity coefficients of the ionized to the unionized species of the probe [6]. The application of the Hammett acidity function was extended to solid systems [5,10,13]. Indicators were used to evaluate solid-state acidity using diffuse reflectance spectroscopy. In this method, the ionization of an indicator in solutions is measured using UV-VIS spectroscopy. The data are then used to construct a calibration curve. The same indicator is then added to solid samples and the ionization is measured using diffuse reflectance spectroscopy. The solid-state acidity is then determined from the calibration curves that were previously constructed.
Appraisal of heavy metal toxicity in surface water with human health risk by a novel approach: a study on an urban river in vicinity to industrial areas of Bangladesh
Published in Toxin Reviews, 2021
Ram Proshad, Saiful Islam, Tanmoy Roy Tusher, Dan Zhang, Sujan Khadka, Jianing Gao, Satyajit Kundu
The physicochemical parameters along with the heavy metal concentrations in the surface water of the Rupsa river is presented in Table 1. The values of all the studied water quality parameters including pH, EC, and heavy metal (Cr, Ni, Cu, As, Cd and Pb) concentrations were found to be higher during the winter season as compared to the values obtained during the summer season. The mean pH was observed as 7.97 ± 0.052 and 8.07 ± 0.053 during the summer and the winter season, respectively, while the pH values were ranged from 7.53 to 8.76 during the summer and from 7.62 to 8.87 during the winter season (Table 1). The pH value represents the acidity or alkalinity of the water (Ravikumar ET AL. 2013). A pH value ranged between 6 and 8.5 indicates a productive water body (Garg ET AL. 2010), whereas the water with a low pH value is considered to be corrosive and can adversely affect the skin and eyes (Li ET AL. 2017). The observed pH values in this study indicated that the river water is productive and suitable for human consumption. Islam ET AL. (2018a) observed the mean water pH of Rupsa river as 8.5, ranged from 8.1 to 9.0 during a hydrological year 2016–2017, which was slightly higher than the mean pH value of 8.2 calculated for the whole hydrological year considered in this study regardless of the seasonal variations. Ali ET AL. (2016) studied the water quality of Karnaphuli river, one of the major coastal rivers in Bangladesh, and also found similar result like present study.
Assessment of trace element toxicity in surface water of a fish breeding river in Bangladesh: a novel approach for ecological and health risk evaluation
Published in Toxin Reviews, 2022
Md. Refat Jahan Rakib, Yeasmin Nahar Jolly, Bilkis Ara Begum, Tasrina Rabia Choudhury, Konika Jannat Fatema, Md. Saiful Islam, Mir Mohammad Ali, Abubakr M. Idris
Mean values of physical–chemical parameters of surface water samples from Halda River, Bangladesh are shown in Table 1. The pH of the aquatic systems is an important indicator of the water quality and the extent pollution in the watershed areas. It is the indicator of acidic or alkaline condition of water status. The standard for any purpose in-terms of pH is 6.5–8.5, in that respect; the mean value of pH in this study is 6.02 which indicates slightly acidic water. The pH value represents the acidity or alkalinity of the water (Ravikumar et al. 2013). A pH value ranged between 6 and 8.5 indicates a productive water body (Garg et al.2010), whereas the water with a low pH value is considered to be corrosive and can adversely affect the skin and eyes (Li et al.2017). APHA (2012) stated that industrial or municipal waste materials played a significant role in increasing or decreasing pH of the adjacent water body. Moreover, activities like bathing, washing, and latrines along water bodies related to fluctuations of water pH (Islam et al.2018a). Biochemical and chemical reactions are influenced by the pH (Manjare et al. 2010). Ali et al. (2016) studied the water quality of Karnaphuli River, one of the major coastal rivers in Bangladesh, and also found similar result of this study.
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