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2021 ◽  
pp. 66-74
Author(s):  
N. O. Appazov ◽  
B. M. Bazarbayev ◽  
T. Assylbekkyzy ◽  
B. M. Diyarova ◽  
S. A. Kanzhar ◽  
...  

This paper presents the results of research on obtaining biochar from agricultural plant waste such as rice husk and straw. The selection of the optimal conditions for thermolysis, such as the duration and temperature of the process, has been conducted. The thermolysis products are characterized for iodine adsorption activity, cumulative water pore volume, and for bulk density. The porous structure of the obtained products has been studied by scanning electron microscopy. Based on the results of the research conducted, it has been found that biochars obtained from husk and straw with a thermolysis duration of 30 minutes have low iodine sorption characteristics and water pore volumes. With an increase in the duration of thermolysis, the sorption characteristics improve, the optimal for the husk is the thermolysis duration of 60 minutes at a temperature of 500°C, and for straw, the optimal thermolysis duration is 60 minutes at a temperature of 300°C. The best option is biochar obtained from rice straw at a duration of 60 minutes and a thermolysis temperature of 300°C, having an iodine adsorption activity of 54.61%, a cumulative water pore volume of 0.941 cm3/g and a bulk density of 169.29 g/dm3. The obtained biochars from rice husk and straw have been studied by scanning electron microscopy at 4300 and 5000 times magnification, and they have a developed porous structure. According to the literature, it is known that biochar can also be used as a renewable energy source. Research has been carried out to determine the calorific value of the obtained biochars. To compare the calorific value of rice husk, straw and the obtained biochars, their heating values have been determined on a calorimeter. The highest heating value has a biochar obtained from husk at a duration of 60 minutes and at a thermolysis temperature of 400°C with a value of 17.520 kJ/g, the optimal for biochar obtained from straw is a duration of 60 minutes and a thermolysis temperature of 400°C with a value of 16.451 kJ/g. The experimental data obtained make it possible to use the obtained biochar from rice straw in the future as a biofertilizer to improve the characteristics of soils, as well as to use biochar obtained from rice husk to produce renewable fuel.


2021 ◽  
Vol 311 ◽  
pp. 110680
Author(s):  
M. Fleury ◽  
T. Chevalier ◽  
R. Jorand ◽  
I. Jolivet ◽  
B. Nicot

2020 ◽  
Vol 41 (Supplement_2) ◽  
Author(s):  
V Montiel ◽  
R Bella ◽  
L Michel ◽  
E Robinson ◽  
J.C Jonas ◽  
...  

Abstract Background Pathological remodeling of the myocardium has long been known to involve oxidant signaling, but so far, strategies using systemic anti-oxidants have generally failed to prevent it. Aquaporins are a family of transmembrane water channels with thirteen isoforms currently known. Some isoforms have been implicated in oxidant signaling. AQP1 is the most abundant aquaporin in cardiovascular tissues but its specific role in cardiac remodeling remains unknown. Purpose We tested the role of AQP1 as a key regulator of oxidant-mediated cardiac remodeling amenable to targeted pharmacological therapy. Methods We used mice with genetic deletion of Aqp1 (and wild-type littermate), as well as primary isolates from the same mice and human iPSC/Engineered Heart Tissue to test the role of AQP1 in pro-hypertrophic signaling. Human cardiac myocyte-specific (PCM1+) expression of AQP's and genes involved in hypertrophic remodeling was studied by RNAseq and bioinformatic GO pathway analysis. Results RNA sequencing from human cardiac myocytes revealed that the archetypal AQP1 is a major isoform. AQP1 expression correlates with the severity of hypertrophic remodeling in patients with aortic stenosis. The AQP1 channel was detected at the plasma membrane of human and mouse cardiac myocytes from hypertrophic hearts, where it colocalizes with the NADPH oxidase-2 (NOX2) and caveolin-3. We show that hydrogen peroxide (H2O2), produced extracellularly, is necessary for the hypertrophic response of isolated cardiac myocytes and that AQP1 facilitates the transmembrane transport of H2O2 through its water pore, resulting in activation of oxidant-sensitive kinases in cardiac myocytes. Structural analysis of the amino acid residues lining the water pore of AQP1 supports its permeation by H2O2. Deletion of Aqp1 or selective blockade of AQP1 intra-subunit pore (with Bacopaside II) inhibits H2O2 transport in mouse and human cells and rescues the myocyte hypertrophy in human induced pluripotent stem cell-derived engineered heart muscle. This protective effect is due to loss of transmembrane transport of H2O2, but not water, through the intra-subunit pore of AQP1. Treatment of mice with clinically-approved Bacopaside extract (CDRI08) inhibitor of AQP1 attenuates cardiac hypertrophy and fibrosis. Conclusion We provide the first demonstration that AQP1 functions as an aqua-peroxiporin in primary rodent and human cardiac parenchymal cells. We show that cardiac hypertrophy is mediated by the transmembrane transport of H2O2 through the AQP1 water channel. Our studies open the way to complement the therapeutic armamentarium with specific blockers of AQP1 for the prevention of adverse remodeling in many cardiovascular diseases leading to heart failure. Funding Acknowledgement Type of funding source: Public grant(s) – National budget only. Main funding source(s): FRS-FNRS, Welbio


2020 ◽  
Vol 12 (564) ◽  
pp. eaay2176
Author(s):  
Virginie Montiel ◽  
Ramona Bella ◽  
Lauriane Y. M. Michel ◽  
Hrag Esfahani ◽  
Delphine De Mulder ◽  
...  

Pathological remodeling of the myocardium has long been known to involve oxidant signaling, but strategies using systemic antioxidants have generally failed to prevent it. We sought to identify key regulators of oxidant-mediated cardiac hypertrophy amenable to targeted pharmacological therapy. Specific isoforms of the aquaporin water channels have been implicated in oxidant sensing, but their role in heart muscle is unknown. RNA sequencing from human cardiac myocytes revealed that the archetypal AQP1 is a major isoform. AQP1 expression correlates with the severity of hypertrophic remodeling in patients with aortic stenosis. The AQP1 channel was detected at the plasma membrane of human and mouse cardiac myocytes from hypertrophic hearts, where it colocalized with NADPH oxidase-2 and caveolin-3. We show that hydrogen peroxide (H2O2), produced extracellularly, is necessary for the hypertrophic response of isolated cardiac myocytes and that AQP1 facilitates the transmembrane transport of H2O2 through its water pore, resulting in activation of oxidant-sensitive kinases in cardiac myocytes. Structural analysis of the amino acid residues lining the water pore of AQP1 supports its permeation by H2O2. Deletion of Aqp1 or selective blockade of the AQP1 intrasubunit pore inhibited H2O2 transport in mouse and human cells and rescued the myocyte hypertrophy in human induced pluripotent stem cell–derived engineered heart muscle. Treatment of mice with a clinically approved AQP1 inhibitor, Bacopaside, attenuated cardiac hypertrophy. We conclude that cardiac hypertrophy is mediated by the transmembrane transport of H2O2 by the water channel AQP1 and that inhibitors of AQP1 represent new possibilities for treating hypertrophic cardiomyopathies.


2018 ◽  
pp. 84-88
Author(s):  
N. F. Chistyakova

The article deals with the analysis of the chemical composition of pore solutions pressed from terrigenous rocks at pressures of 5-10-15-400 atm. Particular attention is paid to sulfate and hydrocarbonate ions of relict water - pore solutions - indicators of the realization of the oil and gas potential of rocks containing dispersed organic matter of subaquatic origin at the stage of catagenesis.


2017 ◽  
Vol 33 (2) ◽  
pp. 234-242 ◽  
Author(s):  
Bing Bu ◽  
Dechang Li ◽  
Jiajie Diao ◽  
Baohua Ji

Soft Matter ◽  
2016 ◽  
Vol 12 (5) ◽  
pp. 1601-1609 ◽  
Author(s):  
Alice Berthaud ◽  
François Quemeneur ◽  
Maxime Deforet ◽  
Patricia Bassereau ◽  
Françoise Brochard-Wyart ◽  
...  

Aquaporin 0 (AQP0) is a transmembrane protein specific to the eye lens, involved as a water carrier across the lipid membranes. We propose here a new method based on GUV spreading to measure the water permeability of membrane and single functional water pore. We also demonstrate that truncated AQP0 do not conduct water.


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