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Global circulation and liquid back mixing adversely affect the continuous production of a multistage internal airlift loop reactor. A contraction-expansion guide vane (CEGV) is proposed and combined with a two-stage internal loop airlift reactor (TSILALR) to suppress the liquid back mixing between stages. A computational fluid dynamics (CFD) simulation is conducted to evaluate the performance of the CEGV in the TSILALR. The bubble size distribution and turbulent flow properties in the TSILALR are considered in the CFD simulation by using the population balance model and RNG k-ε turbulence model. The CFD model is validated against the experimental results. The deviations in the gas holdup and mean bubble diameter between the simulation and experimental results are less than 8% and 6%, respectively. The streamlines, flow pattern, bubble size distribution, and axial liquid velocity in the TSILALRs with and without the CEGV at superficial velocities of 0.04 and 0.08 m/s are obtained by CFD simulation. It has been shown that the CEGV generated local circulation flows at each stage instead of a global circulation flow in the TSILALR. The average global gas holdup in the TSILALR with a CEGV increased up to 1.98 times. The global gas holdup increased from 0.045 to 0.101 and the average axial velocity in the riser decreased from 0.314 to 0.241 m/s when the width of the CEGV increased from 50 to 75 mm at the superficial gas velocity of 0.08 m/s.

Searching for one-dimensional (1D) nanostructure with ferromagnetic (FM) half-metallicity is of significance for the development of miniature spintronic devices. Here, based on the first-principles calculations, we propose that the 1D CrN nanostructure is a FM half-metal, which can generate the fully spin-polarized current. The ab initio molecular dynamic simulation and the phonon spectrum calculation demonstrate that the 1D CrN nanostructure is thermodynamically stable. The partially occupied Cr-d orbitals endow the nanostructure with FM half-metallicity, in which the half-metallic gap (Δs) reaches up to 1.58 eV. The ferromagnetism in the nanostructure is attributed to the superexchange interaction between the magnetic Cr atoms, and a sizable magnetocrystalline anisotropy energy (MAE) is obtained. Moreover, the transverse stretching of nanostructure can effectively modulate Δs and MAE, accompanied by the preservation of half-metallicity. A nanocable is designed by encapsulating the CrN nanostructure with a BN nanotube, and the intriguing magnetic and electronic properties of the nanostructure are retained. These novel characteristics render the 1D CrN nanostructure as a compelling candidate for exploiting high-performance spintronic devices.

BACKGROUND Hyperphosphatemia, hypocalcemia, and elevation of parathyroid hormone (PTH) are typical abnormalities of uremic patients with Secondary hyperparathyroidism (SHPT). However, metabolic imbalance associated with SHPT is not well understood. METHODS A total of 15 SHPT patients with an intact parathyroid hormone (iPTH) level > 600 pg/mL were set as preoperative (PR) group, 15 age- and gender-matched controls who had undergone parathyroidectomy plus forearm transplantation because of hyperparathyroidism and achieved an iPTH level

Background Chlorpyrifos (CPF) is one of the most widely used organophosphorus pesticides globally and can accumulate in the kidney. Researchers have confirmed the regulatory functions of long non-coding ribonucleic acid (lncRNA) in the kidney. However, very few studies have examined the effects of prenatal CPF exposure or lncRNA on kidney development. Methods High-throughput ribonucleic acid (RNA) sequencing was performed on embryonic kidneys obtained at E12.5, E14.5, E16.5, and E18.5 of prenatal CPF-exposed mice and the dimethyl sulfoxide (DMSO) control mice. A weighted gene co-expression network analysis (WGCNA) and a functional enrichment analysis were applied to construct a lncRNA-messenger ribonucleic acid (mRNA) network and screen targeted genes. These strategies were used to select the modules and genes correlated with prenatal CPF exposure in mouse kidney development. Results A gene ontology (GO) analysis revealed that the hub mRNAs linked to prenatal CPF exposure were mainly involved in the extracellular matrix and collagen degradation. Prss1, Prss2, and Prss3 were the most significantly upregulated mRNAs, and all had strong connections to lncRNAs Gm28760, Gm28139, and Gm26717. Additionally, we analyzed the lncRNA-mRNA network at different developmental kidney stages after prenatal CPF exposure. The results showed that kidney development was blocked at E12.5, which led to ectopic proximal tubule formation at E18.5. Conclusions In summary, the RNA-sequencing and weighted gene co-expression network analyses showed that molecular phenotype changes occur in kidney development in a prenatal CPF exposure mouse model.

Disturbed intrauterine development increases the risk of renal disease. Various studies have reported that Notch signalling plays a significant role in kidney development and kidney diseases. A disintegrin and metalloproteinase domain 10 (ADAM10), an upstream protease of the Notch pathway, is also reportedly involved in renal fibrosis. However, how ADAM10 interacts with the Notch pathway and causes renal fibrosis is not fully understood. In this study, using a prenatal chlorpyrifos (CPF) exposure mouse model, we investigated the role of the ADAM10/Notch axis in kidney development and fibrosis. We found that prenatal CPF‐exposure mice presented overexpression of Adam10, Notch1 and Notch2, and led to premature depletion of Six2+ nephron progenitors and ectopic formation of proximal tubules (PTs) in the embryonic kidney. These abnormal phenotypic changes persisted in mature kidneys due to the continuous activation of ADAM10/Notch and showed aggravated renal fibrosis in adults. Finally, both ADAM10 and NOTCH2 expression were positively correlated with the degree of renal interstitial fibrosis in IgA nephropathy patients, and increased ADAM10 expression was negatively correlated with decreased kidney function evaluated by serum creatinine, cystatin C, and estimated glomerular filtration rate. Regression analysis also indicated that ADAM10 expression was an independent risk factor for fibrosis in IgAN. © 2020 The Authors. The Journal of Pathology published by John Wiley & Sons, Ltd. on behalf of The Pathological Society of Great Britain and Ireland.

Acute rejection (AR) can lead to allograft dysfunction following renal transplantation, despite immunosuppressive treatments. Accumulating evidence points out a role for epigenetic modification in immune responses. However, the mechanism and contribution of DNA methylation in allograft survival remain unclear. In this study, we followed up patients who successively experienced end‐stage renal disease, renal transplantation with allograft function or dysfunction, and hemodialysis. Peripheral blood mononuclear cells were collected at different time points for analysis of the DNA methylation. Epigenetic modifier analysis was also performed to explore its effect of methylation in a mouse model of AR. Compared with the allograft‐stable cohort, patients who experienced AR‐induced allograft dysfunction demonstrated more changes in methylation patterns. Pathway analysis revealed that the hypermethylated areas in the allograft dysfunction group were associated with genes related to the mechanistic target of rapamycin (mTOR) signaling pathway. Moreover, in the mouse AR model, treatment with the DNA methyltransferase inhibitor—decitabine regulated the Th1/2/17/regulatory T cell (Treg cell) immune response via its demethylating role in the suppressing the activity of the mTOR pathway, which ultimately ameliorated renal allograft‐related inflammatory injuries. These results revealed that changes in methylation accompany AR‐induced allograft dysfunction after renal transplantation. Epigenetics may provide new insights into predicting and improving allograft survival., Whole‐genome bisulfite sequencing explores epigenetic changes in renal transplant recipients, revealing enhanced hypermethylation of genes enriched in immune‐related pathways.

Intact parenchyma cells were successfully isolated from potato tuber and chemically cross-linked with 5–12 wt.% sodium trimetaphosphate/sodium tripolyphosphate for investigating the effect of cross-linking on the structural characteristics and enzyme susceptibility of starch encapsulated within the cell walls. The results indicated that both starch and cell wall polysaccharides were cross-linked, and the swelling power of starch was significantly decreased with increasing degree of cross-linking. The cross-linking reaction also significantly reduced the rate and extent of starch digestion in both intact and disrupted cells after cooking. In addition, the cell-wall barrier effect on starch digestion increased with the degree of cross-linking, due probably to that limited starch swelling and pectin solubilization during cooking process partially protected cell wall integrity and thus decreased cell wall permeability. Overall, the study suggests that chemically cross-linking of cell wall polysaccharides can slow down the in vitro starch digestion of cooked potato foods.

Anion polyacrylamide (APAM) fouling towards anion exchange membrane (AEM) during electrodialysis (ED) of industrial effluent draws recent attention. The fouling dynamics was herein investigated via different approaches in monitoring the variation of the solution and membrane properties. The results showed that conductivity and pH variation is less sensitive than electrochemical signals via transmembrane electric potential (TMEP) and electrochemical impedance spectroscopy (EIS) focusing on micro-scale variation occurred on/near the membrane interface. Initially, the deposition of APAM caused few current transfer limitations as supported by the plateau region for the TMEP profile. Further building-up of APAM fouling gradually hindered the current transfer, resulting into an increased TMEP due to the formation of gel layer on AEM and/or blockage of free volume. Later, the water splitting indicated by an obvious pH variation in dilute and concentrate occurred, which may further accelerate the fouling via modifying the particle size of APAM. EIS successfully distinguished the electrochemical property of membrane bulk and boundary layer, implying the internal fouling is largely responsible for the increased membrane resistance. Future work is suggested to further clarify the external and internal fouling on ion exchange membrane (IEM) and investigate effective fouling mitigation methods in ED.

Economic optimization is an important engineering aspect of modern distillation. A screening-clustering assisted kriging optimization (SCAKO) method is proposed herein to optimize the economics of the distillation process. The SCAKO consists of a kriging surrogate model, an expected improvement sampling approach, a screening-clustering operation, and a quantum-behaved particle swarm optimization algorithm. The main feature of the SCAKO method is the combination of an effective search domain contraction approach and the kriging surrogate model. The insignificant sampled points are deleted from the dataset, and the remaining sampled points are divided into a series of clusters. The search domain is then divided into several sub-domains according to the information of the points in the clusters. Kriging surrogate model is constructed to represent the variation trend of the optimization objective in each sub-domain. Case studies were performed to validate the computational effectiveness and efficiency of the SCAKO.

A multiscale model for simulating the hydrodynamic behavior of catalytic bale packings has been proposed. This model combines computational fluid dynamics (CFD) and macroscopic calculation. At small scale calculation, the CFD model includes 3-D volume-of-fluid (VOF) simulation within representative elementary unit (REU) under unsteady-state conditions. The REU constitutes gauze and catalyst domain, and porous media model is applied. At large scale calculation, a new mechanistic model deduced from the unit network model is employed. Based on liquid split proportion from small scale calculation, liquid distribution of the entire bale packing can be predicted. To evaluate different packing design, three common bale arrangements, i.e. one-bale, nine-bales and seven-bales, are compared. The area-weighted Christiansen uniformity coefficient is introduced to assess the distribution performance. A comparison between simulation and experimental results is made to validate the multiscale model. The present methodology is proved to be effective to analysis and design of catalytic distillation columns.

The response technique was employed to investigate the axial and radial dispersion characteristics of the liquid phase in modular catalytic structured packing (MCSP) reaction elements. Residence time distribution (RTD) experiments were performed at ambient temperature and atmospheric pressure. A two-dimensional dispersion model was solved analytically to determine the axial and radial dispersion coefficients and the dynamic liquid holdup from the RTD curves. Three different reaction elements containing Winpak packing sheets, Mellapak packing sheets, or only catalytic particles were employed. The radial dispersion coefficient in these structures is approximately 1–2 orders of magnitude higher than the axial dispersion coefficient. The axial and radial dispersion coefficients in the Winpak elements are greater than those in the other structures. Thus, it can be concluded that the liquid dispersion characteristics in the Winpak elements are satisfactory. These measured dispersion coefficients enable the reli...

The use of catalytic distillation (CD) in chemical production has gained popularity in recent years, as it results in minimized installation costs and increased efficiency. However, the design of suitable modular catalytic structured packing (MCSP) for CD processes remains a challenge. This paper presents a novel MCSP named Winpak-C. The hydraulic performance of Winpak-C is investigated in a 400-mm diameter column with an air-water system. Predictive models for the pressure drop and liquid holdup are proposed, which provide reasonably close predictions. The models describe the gas loading point, which reflects the transition from the liquid loading regime to the unstable flooding regime. Further, a visual experiment is performed to determine the maximum liquid load of the catalyst-containing bags, and the flow behaviours around the liquid load point are described. In addition, a tracer method is employed to determine the liquid residence time distribution (RTD). The Peclet number and axial dispersion coefficient deduced from RTD curves are discussed and compared with those for traditional MCSP. This study on the hydraulics of Winpak-C is significant for the design and scale-up of CD processes.

A recently designed packing sheet Winpak was assembled with catalysts in a modular catalytic structured packing (MCSP) column. A combined mesoscale–microscale methodology was used to analyze and determine the pressure drop mechanism in the MCSP. The proposed methodology differentiates the pressure drop into six different principles, which was determined and compared using computational fluid dynamics (CFD). The three major causes are gas flow confluence and diffluence through the packing windows, the sudden change in the effective gas channel area and the wall effect. Inspired by constructal theory, the height of packing sheets loaded with catalysts was reduced, which resulted in a less abrupt gas channel contraction and expansion at the packing layer junction and more favorable for the undisturbed gas flow. The optimized overall pressure drop was reconstructed in Fluent and was validated by both dry and irrigated packing experiments. Furthermore, irrigated packing experiments were also conducted. Result ...

Rationale: Atrial fibrillation (AF) contributes significantly to morbidity and mortality in elderly and hypertensive patients and has been correlated to enhanced atrial fibrosis. Despite a lack of direct evidence that fibrosis causes AF, reversal of fibrosis is considered a plausible therapy. Objective: To evaluate the efficacy of the antifibrotic hormone relaxin (RLX) in suppressing AF in spontaneously hypertensive rats (SHR). Methods and Results: Normotensive Wistar-Kyoto (WKY) and SHR were treated for 2 weeks with vehicle (WKY+V and SHR+V) or RLX (0.4 mg/kg per day, SHR+RLX) using implantable mini-pumps. Hearts were perfused, mapped optically to analyze action potential durations, intracellular Ca 2+ transients, and restitution kinetics, and tested for AF vulnerability. SHR hearts had slower conduction velocity (CV; P P P P P + current density, I Na (≈2-fold in 48 hours) in human cardiomyocytes derived from inducible pluripotent stem cells (n=18/18; P Conclusions: RLX treatment suppressed AF in SHR hearts by increasing CV from a combination of reversal of fibrosis and hypertrophy and by increasing I Na . The study provides compelling evidence that RLX may provide a novel therapy to manage AF in humans by reversing fibrosis and hypertrophy and by modulating cardiac ionic currents.

The calcium pump SERCA2a (sarcoplasmic reticulum calcium ATPase 2a), which plays a central role in cardiac contraction, shows decreased expression in heart failure (HF). Increasing SERCA2a expression in HF models improves cardiac function. We used direct cardiac delivery of adeno-associated virus encoding human SERCA2a (AAV6-hSERCA2a) in HF and normal canine models to study safety, efficacy, and the effects of immunosuppression. Tachycardic-paced dogs received left ventricle (LV) wall injection of AAV6-hSERCA2a or solvent. Pacing continued postinjection for 2 or 6 weeks, until euthanasia. Tissue/serum samples were analyzed for hSERCA2a expression (Western blot) and immune responses (histology and AAV6-neutralizing antibodies). Nonpaced dogs received AAV6-hSERCA2a and were analyzed at 12 weeks; a parallel cohort received AAV-hSERCA2a and immunosuppression. AAV-mediated cardiac expression of hSERCA2a peaked at 2 weeks and then declined (to ∼50%; p

More and more enterprises are willing to use gift cards for product promotion. In this paper, we assume that the consumer utility function is a nonlinear utility function based on the previous research. We describe consumers' purchasing behavior without a spending constraint from the perspective of consumers' utility and develop a model to derive the optimal purchase amount threshold, gift card value under single gift card and two gift cards. In a certain extent, this paper makes up for the lack of gift cards in the theoretical research.

To investigate the level of plasma interleukin 37 (IL-37) and explore the clinical significance of IL-37 in patients with active pulmonary tuberculosis (ATB).ELISA was used to detect the level of plasma IL-37 from 30 patients with ATB, 15 patients who had been treated for ATB, and 21 healthy volunteers as controls.The level of plasma IL-37 in patients with ATB was significantly higher than that in healthy controls. The monitoring on the 15 patients showed that plasma IL-37 was reduced after treatment for ATB. The level of plasma IL-37 in patients with anti-Mycobecterium tuberculosis antibody positive or sputum smear positive were higher than that in patients with anti-Mycobecterium tuberculosis antibody negative or sputum smear negative for Mycobecterium tuberculosis, and the level was negatively correlated with the number of white blood cells in peripheral blood.The patients with ATB present with significantly increased level of plasma IL-37, which might be an indicator of curative effect in ATB.

To investigate the role of serum soluble triggering receptor expressed on myeloid cells-1 (sTREM-1) in patients with active pulmonary tuberculosis (ATB) and explore its clinical significance.The study included 78 cases of ATB patients and 40 cases of healthy volunteers from Dongguan Hospital for Chronic Diseases. Peripheral blood neutrophils and monocytes were counted by automated hematology analyzer. Serum sTREM-1 levels were detected by ELISA, and then the relevance with neutrophils and monocytes were analyzed by Pearson correlation test, respectively.The absolute numbers of neutrophils and monocytes, and the levels of serum sTREM-1 were higher in ATB patients than those in normal controls. In smear positive patients, the absolute numbers of neutrophils and monocytes, and the levels of serum sTREM-1 were higher than those in smear negative patients. The absolute numbers of neutrophils and monocytes, and the levels of serum sTREM-1 decreased in ATB patients after anti-TB drug treatments. Serum sTREM-1 level ≥ 528.14 pg/mL was very useful to diagnosis the smear positive ATB, and the accuracy was 100%. Pearson correlation test revealed that the absolute numbers of neutrophils and monocytes were both positively correlated to the levels of serum sTREM-1.High serum levels of sTREM-1 may be of high value for early warning and prediction of poor prognosis in ATB patients.

Although tuberculous pleurisy (TP) presumably involves a hypersensitivity reaction, there is limited evidence indicating overreactive effector responses of γδ T cells and αβ T cells and their interrelation with Foxp3+ Tregs in pleural and other compartments. We found that TP induced reciprocal representations of Foxp3+ Tregs and Mtb phosphoantigen-specific Vγ2Vδ2 T cells in different anatomic compartments. Patients with TP exhibited appreciable numbers of “proliferating” Ki-67+ Vγ2Vδ2 T cells in the airway where Foxp3+ Tregs were not dominant, whereas striking increases in Foxp3+ Tregs in the blood and pleural compartments coincided with low frequencies of Vγ2Vδ2 T cells. Interestingly, anti-tuberculosis chemotherapy control of Mtb infection in patients with TP reversed reciprocal representations of Foxp3+ Tregs and proliferating Vγ2Vδ2 T cells. Surprisingly, despite high-level Foxp3+ Tregs, TP appeared to drive overreactive responses of IFN-γ-producing Vγ2Vδ2, CD4+CD25+, and CD8+CD25+ T effector subpopulations, whereas IL-22-producing Vγ2Vδ2 T cells increased subtly. Th1 effector responses were sustained despite remarkable declines in Foxp3+ Tregs at 1 mo after the treatment. Overreactive T effector responses of Mtb-reactive γδ T cells, αβ CD25+CD4+, and CD25+CD8+ T cell subpopulations appear to be immune features for TP. Increased Foxp3+ Tregs might be responsive to overreactive TP but unable to influence T effector responses despite having an inverse relation with proliferating Vγ2Vδ2 T cells.