On the objectivity of mathematical description of ion transport processes using general temporal Caputo and Riemann-Liouville fractional partial derivatives

2022 ◽  
Vol 156 ◽  
pp. 111802
Author(s):  
Agneta M. Balint ◽  
Stefan Balint ◽  
Adrian Neculae
2010 ◽  
Vol 299 (1) ◽  
pp. R92-R100 ◽  
Author(s):  
Jens Berger ◽  
Martin Hardt ◽  
Wolfgang G. Clauss ◽  
Martin Fronius

A thin liquid layer covers the lungs of air-breathing vertebrates. Active ion transport processes via the pulmonary epithelial cells regulate the maintenance of this layer. This study focuses on basolateral Cl− uptake mechanisms in native lungs of Xenopus laevis and the involvement of the Na+/K+/2 Cl− cotransporter (NKCC) and HCO3−/Cl− anion exchanger (AE), in particular. Western blot analysis and immunofluorescence staining revealed the expression of the NKCC protein in the Xenopus lung. Ussing chamber experiments demonstrated that the NKCC inhibitors (bumetanide and furosemide) were ineffective at blocking the cotransporter under basal conditions, as well as under pharmacologically stimulated Cl−-secreting conditions (forskolin and chlorzoxazone application). However, functional evidence for the NKCC was detected by generating a transepithelial Cl− gradient. Further, we were interested in the involvement of the HCO3−/Cl− anion exchanger to transepithelial ion transport processes. Basolateral application of DIDS, an inhibitor of the AE, resulted in a significantly decreased the short-circuit current (ISC). The effect of DIDS was diminished by acetazolamide and reduced by increased external HCO3− concentrations. Cl− secretion induced by forskolin was decreased by DIDS, but this effect was abolished in the presence of HCO3−. These experiments indicate that the AE at least partially contributes to Cl− secretion. Taken together, our data show that in Xenopus lung epithelia, the AE, rather than the NKCC, is involved in basolateral Cl− uptake, which contrasts with the common model for Cl− secretion in pulmonary epithelia.


Physiology ◽  
1988 ◽  
Vol 3 (3) ◽  
pp. 97-99
Author(s):  
M Wiederholt

The cornea and lens of the eye are avascular transparent tissues that allow almost unimpeded transmission of light to the retina. The transparency of the cornea is a function of hydration, which in turn is affected by electrolyte transport processes across the cellular barriers.


Physiology ◽  
2017 ◽  
Vol 32 (5) ◽  
pp. 367-379 ◽  
Author(s):  
Julian L. Seifter ◽  
Hsin-Yun Chang

Clinical assessment of acid-base disorders depends on measurements made in the blood, part of the extracellular compartment. Yet much of the metabolic importance of these disorders concerns intracellular events. Intracellular and interstitial compartment acid-base balance is complex and heterogeneous. This review considers the determinants of the extracellular fluid pH related to the ion transport processes at the interface of cells and the interstitial fluid, and between epithelial cells lining the transcellular contents of the gastrointestinal and urinary tracts that open to the external environment. The generation of acid-base disorders and the associated disruption of electrolyte balance are considered in the context of these membrane transporters. This review suggests a process of internal and external balance for pH regulation, similar to that of potassium. The role of secretory gastrointestinal epithelia and renal epithelia with respect to normal pH homeostasis and clinical disorders are considered. Electroneutrality of electrolytes in the ECF is discussed in the context of reciprocal changes in Cl−or non Cl−anions and [Formula: see text].


Science ◽  
1978 ◽  
Vol 199 (4332) ◽  
pp. 994-996 ◽  
Author(s):  
R. Izatt ◽  
N. Izatt ◽  
B. Rossiter ◽  
J. Christensen ◽  
B. Haymore

2013 ◽  
Vol 309 ◽  
pp. 358-365 ◽  
Author(s):  
Béla Illés ◽  
Gabriella Bognár

A fast and efficient way of handling and storing components, raw materials, semi-finished and finished products play a significant role in the development of transport, storage and distribution design within the supply chain. One of the most important issues in storage and transport processes is the formation of unit loads. Our main goal is to give a mathematical description of a model involving the major factors of the unit load formation. The optimization process is exhibited applying the determined objective functions and constraints related to the basic tasks.


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