background: this study aimed to compare intermittent intravenous (iv) pantoprazole and ranitidine for control of gastric acid secretion and the possible prevention of upper gastrointestinal bleeding (ugib) in critical care patients. methods: this was a randomized, double blind clinical trial study of iv pantoprazole (40 mg every12 hour) or intermittent iv ranitidine (50 mg bolus every 8 hour) i...

This study investigated the effect of simulated acid rain (SAR) (heavy: pH 2.5; moderate: pH 4.0; and control: pH 5.6) stress on the growth and net photosynthetic rate (Pn) of five tree species, namely Castanopsis sclerophylla, Cinnamomum camphora, Manglietia fordiana, Pinus massoniana, and Elaeocarpus glabripetalus. Results showed variable responses to SAR with different pH values depending on...

Alkaline soils comprise 30% of the earth and have low plant-available iron (Fe) concentration, and can cause iron deficiency chlorosis (IDC). IDC causes soybean yield losses of $260 million annually. However, it is not known whether molecular responses to IDC are equivalent to responses to low iron supply. IDC tolerant and sensitive soybean lines provide a contrast to identify specific factors ...

Acid–base regulation is one of the most tightly regulated physiological processes among vertebrates, and the specific mechanisms and patterns of acid– base regulation in fish have been investigated for decades, although primarily on a few species of teleosts and elasmobranchs. The most common response observed in fish during short-term (up to 96 h) exposure to hypercarbia (elevated environmenta...

This study investigated features of the acid tolerance response (ATR) in Lactobacillus casei ATCC 334. To optimize ATR induction, cells were acid adapted for 10 or 20 min at different pH values (range, 3.0 to 5.0) and then acid challenged at pH 2.0. Adaptation over a broad range of pHs improved acid tolerance, but the highest survival was noted in cells acid adapted for 10 or 20 min at pH 4.5. ...

Cells of Sinorhizobium meliloti WSM419 showed an adaptive acid-tolerance response when grown at pH 5.8 instead of pH 7.0. Increasing concentrations of calcium in the exposure medium significantly decreased the death rate of WSM419 cells under conditions of acid stress (pH 4.0). The effect of calcium on survival at pH 4.0 however, appears unconnected to exopolysaccharide (EPS), since a strain wi...

_ _ Acid deposition has aroused concern about aquatic organisms in soft water lakes and streams, as the loss of indigenous species is commonly observed when pH decreases. This literature review was initiated to intensively examine the distribution of invertebrates with respect to pH, in order to define the tolerance limits of various species in acidified waters and predict how acidification wou...

Understanding how declining seawater pH caused by anthropogenic carbon emissions, or ocean acidification, impacts Southern Ocean biota is limited by a paucity of pH time-series. Here, we present the first high-frequency in-situ pH time-series in near-shore Antarctica from spring to winter under annual sea ice. Observations from autonomous pH sensors revealed a seasonal increase of 0.3 pH units....