● The availability of PD-anammox was investigated with higher NO 3 ––N concentration. ● NO 3 ––N concentration affects NO 3 ––N accumulation during denitrification. ● COD concentration is determinant ...for N removal pathways in PD-anammox process. ● The synergy/competition mechanisms between denitrifiers and anammox was explored.
Partial denitrification-anammox (PD-anammox) is an innovative process to remove nitrate (NO 3 ––N) and ammonia (NH 4 +–N) simultaneously from wastewater. Stable operation of the PD-anammox process relies on the synergy and competition between anammox bacteria and denitrifiers. However, the mechanism of metabolic between the functional bacteria in the PD-anammox system remains unclear, especially in the treatment of high-strength wastewater. The kinetics of nitrite (NO 2 ––N) accumulation during denitrification was investigated using the Michaelis-Menten equation, and it was found that low concentrations of NO 3 ––N had a more significant effect on the accumulation of NO 2 ––N during denitrification. Organic matter was a key factor to regulate the synergy of anammox and denitrification, and altered the nitrogen removal pathways. The competition for NO 2 ––N caused by high COD concentration was a crucial factor that affecting the system stability. Illumina sequencing techniques demonstrated that excess organic matter promoted the relative abundance of the Denitratesoma genus and the nitrite reductase gene nirS, causing the denitrifying bacteria Denitratisoma to compete with Cadidatus Kuenenia for NO 2 ––N, thereby affecting the stability of the system. Synergistic carbon and nitrogen removal between partial denitrifiers and anammox bacteria can be effectively achieved by controlling the COD and COD/NO 3 ––N.
An imbalance between T helper 17 (Th17) and T regulatory (Treg) cell subsets contributes to the pathogenesis of diabetic kidney disease (DKD). However, the underlying regulatory mechanisms that cause ...this imbalance are unknown. Serum/glucocorticoid‐regulated kinase 1 (SGK1) has been suggested to affect Th17 polarization in a salt‐dependent manner, and sodium/glucose cotransporter 2 inhibitors (SGLT2i) have been demonstrated to regulate sodium‐mediated transportation in the renal tubules. This study aimed to evaluate the potential benefits of dapagliflozin (Dap) on DKD, as well as its influence on shifting renal T‐cell polarization and related cytokine secretion. We treated male db/db mice with Dap or voglibose (Vog) and measured blood and kidney levels of Th17 and Treg cells using flow cytometry. We found that Th17 cells were significantly increased, while Treg cells were significantly decreased in diabetic mice. Moreover, Dap suppressed the polarization of Th17/Treg cells by inhibiting SGK1 in diabetic kidneys, and this was accompanied by attenuation of albuminuria and tubulointerstitial fibrosis independent of glycemic control. Taken together, these results demonstrate that the imbalance of Th17/Treg cells plays an important role in the progression of DKD. Moreover, Dap protects against DKD by inhibiting SGK1 and reversing the T‐cell imbalance.
An imbalance between Th17 and Treg cell subsets contributes to the pathogenesis of diabetic kidney disease. We found that Th17 cells were increased, while Treg cells were decreased in diabetic mice. Dapagliflozin suppressed the polarization of Th17/Treg cells by inhibiting SGK1 in diabetic kidneys, and this was accompanied by attenuation of albuminuria and tubulointerstitial fibrosis independent of glycemic control.
The experiment was conducted in a solar greenhouse to determine the optimum irrigation frequency and quantity for cucumber under subsurface drip irrigation based on evaporation from a 20
cm diameter ...pan (
E
p) placed above the crop canopy. Two irrigation intervals (
I1: 4-day and
I2: 8-day) and three plant-pan coefficients (
K
cp1: 0.6;
K
cp2: 0.8 and
K
cp3: 1.0) were compared. Crop evapotranspiration (ET) and fruits yield increased with the increasing of irrigation water. The
K
cp3 treatments had the highest yield, while
K
cp2 had the highest irrigation water use efficiency (IWUE) and water use efficiency (WUE) values in both irrigation intervals. The yields of
K
cp2 treatments decreased only 4.87% and 5.93% in both intervals though total irrigation water decreased 14.3% compared to
K
cp3 treatment. Irrigation water amount significantly (
P
<
0.01) and positively affected the fruit number and fruit water content, whereas significantly and negatively affected the soluble sugar (SS), Vitamin C (Vc) and free amino acid (FAA) content in fruits. In conclusion,
I2
K
cp2 (0.8
E
p with 8-day interval) was the optimum irrigation schedule for cumber plants grown in solar greenhouse under subsurface drip irrigation in arid and semi-arid areas that are in lack of water resources.
Today large space structures are in focus of attention of engineers and designers of rocket and space equipment. In ground-based experiments, it is not always possible to carry out complex tests of ...large space structure functionality. Therefore, the development of mathematical models describing properly the transformable structure dynamics when they opened from the densely packed transport state to the operating position in the orbit becomes very important. To determine the stress-strain state of the frame elements when it is unfolding the shape of the framework is taken at the moments when relative velocities of the adjacent sections are maximal. Supposed, that at these moments the frame elements are getting on the stops limiting their relative angular displacements, and the structure behaves as an elastic rod with specified characteristics. Numerical analysis of the stress-strain state in the framework is carried out by means of a finite element model. Therefore, the represented mathematical model can be effectively used to predict the functional suitability of such transformable space structures already on the early stages of their development.
Large space structures are carried into space orbits in a folded densely packed position, whereas putting them into working position refers to the process of structure deployment. The ground-based ...deployment tryout appears to be extremely expensive, therefore, when developing deployable structures, methods that combine the ground-based tests of physical models of the structure and carrying out of mathematical experiments using designed models for calculation, which appropriately show how the structure behaves during the tests, have their special place. Simulation of such structures deployment during the ground-based tests is performed using as an example a physical model of the circle load-bearing folding frame with diameter of 4 m. A comparison of the results of calculations and the relevant ground-based tests findings helps clarify characteristics of the stops, which are used in the designed models for calculation. Using the designed models for calculation and the clarified stops characteristics, simulation of deployment of the physical model of the structure in the outer space environment is performed.
In this study, we designed and successfully synthesized the Pt/polyoxometalate/hollow carbon sphere (Pt/POM/HCS) tri-component nanoparticles (NPs) by a pollution-free, efficient, and convenient ...method. HCSs with outstanding chemical stability and conductivity are self-generated by acid etching and calcination of silica spheres synthesized by a hard template method. HCSs have a hollow internal structure that provides specific three-dimensional storage space, and can increase the surface area. The mesoporous system is beneficial to providing numerous mass transfer passageways and immobilizing NPs. In addition, we introduced a “double gain strategy”, by taking advantage of POMs as reducing and bridging agents, to achieve the loading of ultrafine Pt NPs on the surface of HCSs. Pt NPs have excellent stability and unique electrocatalytic activity. As a result of the synergistic effect of HCSs and ultrafine Pt NPs, the electrochemical sensing of adrenaline exhibits high-performance catalytic activity, sensitivity, suitable linearity range (0.16 μM−1.195 mM), and low limit of detection (57.5 nM, S/N = 3), excellent stability, and reproducibility. The developed platform is a sensitive and effective adrenaline electrical sensing platform with broad practical application prospects.
We designed and successfully synthesized the Pt/POM/HCS tri-component nanoparticles by a pollution-free and convenient method, and further constructing a relatively accurate, practical, and efficient electrochemical sensor for rapid adrenaline detection. Display omitted
•Decoration of HCSs with ultrafine Pt NPs using POM by a “double gain strategy” strategy.•Pt/POM/HCS have been developed as an efficient electrochemical sensing for adrenaline.•The novel Pt/POM/HCS will hold promise in development of electrode materials.
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•Four electron transfer pathways in Fe(II)-mediated PD/anammox system were proposed.•Fe(II) stimulated autotrophic denitrification, increased narb gene related to NAFO.•Fe(II) ...enhanced cATP and enzymes synthesis, boosting metabolic activities.•Fe(II) enhanced electron transfer system and electron transfer mediators secreting.•Fe(II)-mediated PD/anammox achieved stable operation with NRR of 5.88 g N/L/d.
This study effectively coupled anammox and mixotrophic denitrification at a high nitrogen load rate of 6.84 g N/L/d with 40 mg/L Fe(II). Fe(II) enhanced the activity of nitrate reductase, nitrite reductase, and hydrazine dehydrogenase enzymes, facilitating accelerated ATP synthesis. Through electrochemical experiments, interspecies electron transfer processes in coupled system were explored. Fe(II) promoted flavin mononucleotide secretion, enhancing electron-donating and electron-accepting capacity by 2.8 and 1.3 times, respectively. Fe(II) triggered the enrichment of autotrophic denitrifying bacteria (Azospira and Hydrogenophaga), transitioning from single organic nutrient to mixotrophic denitrification. Meanwhile, Fe(II) increased Candidatus_Kuenenia abundance from 35.2 % to 49.0 %, establishing the competitive advantage of anammox bacteria over completed denitrifying bacteria (Comamonas). The synergistic interactions between anammox and various denitrification pathways achieved a nitrogen removal rate of 5.88 g N/L/d, with anammox contribution rate of 88.3 %. This study provides insights into broadening the application of partial denitrification /anammox and electron transfer in multi-bacterial coupling systems.
The start-up of a relatively high nitrogen load PD/Anammox in an EGSB reactor was achieved through strategies of bioaugmentation, mass transfer enhancement, and COD/NO3−-N control, with NRR of ...5.2 g N/L/d. Longitudinal heterogeneity in EGSB reactor induced divergent nitrogen conversion pathways and enriched different functional microorganisms between stratified sludge. Along the elevation of the reactor, the proportion of removed nitrogen through anammox increased continuously from bottom, middle and up, which were 65.0 %, 79.8 %, and 84.1 %, respectively, consistent with the trend of ex-situ activities calculated with Gompertz model. The bottom zone played a role in mixed nitrogen conversion to provide NO2−-N accumulation and nitrogen removal, with higher abundance of Thauera, Denitratisoma and Ignavibacterium. The middle part was enriched Candidatus_Kuenenia (12.51 %), and up inhibited completed denitrification, together forming the anammox dominant zone. The proposed functional zones in the EGSB reactor provided approaches for the optimisation of high-load PD/Anammox systems.
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•Functional zones of PD/Anammox in EGSB reactor was explored for the first time.•Bottom zone contributed the highest removal as mixed nitrogen conversion zone.•Candidatus Kuenenia was enriched in the middle zone (12.51 %).•The lack of COD inhibited completed denitrification in the up zone.•Proportion of removed nitrogen through anammox increased along the elevation.
Cadmium (Cd) is a common heavy metal pollutant in the environment, and the widespread use of products containing Cd compounds in industry has led to excessive levels in the environment, which enter ...the animal body through the food chain, thus seriously affecting the reproductive development of animals. Related studies have reported that Cd severely affects spermatogonia development and spermatogenesis in animals. In contrast, the reproductive toxicity of Cd in males and its mechanism of action have not been clarified. Therefore, this paper reviewed the toxic effects of Cd on germ cells, spermatogonia somatic cells and hypothalamic-pituitary-gonadal axis (HPG axis) of male animals and its toxic action mechanisms of oxidative stress, apoptosis and autophagy from the perspectives of cytology, genetics and neuroendocrinology. The effects of Cd stress on epigenetic modification of reproductive development in male animals were also analyzed. We hope to provide a reference for the in-depth study of the toxicity of Cd on male animal reproduction.
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