Because underwater and low-light images have different characteristics, there are few methods to jointly improve the visibility of these images. This paper proposes a de-hazing and enhancement method ...for underwater and low-light images to describe the two types of images uniformly. Multi-scale retinex color recovery (MSRCR) and guided filtering methods are used for de-hazing; the proposed method of white balance fusion global guided image filtering (G-GIF), effectively solve the problems of dim light, color distortion, and loss of edge details. Experiments show that compared with other methods, this method can effectively solve the image exposure, and at the same time, it can better protect and enhance the image’s color saturation and edge texture details, thus achieving a very good visual effect.
Polyelectrolytes with abundant ionizable groups always possess excellent adsorption capacity for metal ions. However, these polymer chains are limited for direct application, resulting from lacking a ...fixed shape. In this paper, polypropylene (PP) fibers decorated with high-density polyacrylic acid (PAA) brushes were prepared using modified ultraviolet-induced graft technology and used as an efficient adsorbent for recovering rare-earth elements from wastewater. The preparation conditions for the degree of grafting were optimized with the response surface methodology mode. After grafting, apparent expansion happened to the fibers, and scanning electron microscopy images indicated that the fiber diameter increased from 48 to 175 μm along with the increase of the degree of grafting. By means of attaching one end of PAA chains onto the PP substrate, the free end would be exposed to the surrounding medium, which leads to a huge number of highly accessible adsorption sites and further guaranteed us with a fast adsorption–desorption rate and larger adsorption capacity. Adsorption could reach above 85% of the maximum adsorption capacity, with a magnitude of 435.19 mg·g–1 within 5 min toward a model rare-earth element Ce3+. Isotherm and kinetic analyses were also undertaken. Moreover, the recycling experiment suggested that the adsorbent taken with almost 100% desorption efficiency could be reproduced robustly for several cycles. In addition, the modified PP fiber can be considered as potential column packing because it exhibits higher adsorption capacity and desorption efficiency than commercial D113 and DL001 resins.
•Downshift is effective in improving the energy efficiency of electric vehicles.•Energy improvement of downshift varies with vehicle speed and brake strength.•The designed nonlinear sliding mode ...observer is accurate in estimating bake torque.•The proposed resembling PWM method is practical to regulate hydraulic pressure.•The effect of downshift on braking safety and comfort can be restrained by control.
Downshift during regenerative braking helps to improve the energy efficiency of electric vehicles. Two main problems are involved in the downshift process. One is the determination of optimal downshift point, and the other is the cooperative control of regenerative braking and hydraulic braking. In order to achieve a systemic solution to these problems, a hierarchical control strategy is brought forward for an electric vehicle with a two-speed automated mechanical transmission. For the upper controller, an off-line calculation and on-line look-up table method is adopted to obtain the optimal downshift point, and a series regenerative braking distribution strategy is designed. For the medium controller, a nonlinear sliding mode observer is designed to obtain the actual hydraulic brake torque. For the lower controller, cooperative control of regenerative braking and hydraulic braking is given to ensure brake safety during downshift process, and a resembling pulse width modulation method is proposed to regulated the hydraulic brake torque. Simulation results and hardware-in-loop test show that the proposed algorithm is effective in improving the energy efficiency of electric vehicles.
Automatic clutch control is critical in automated manual transmission systems because clutch actions have a significant influence on the vehicle performance, including safety, comfort, reliability, ...and shifting quality. However, clutch control is a challenging problem due to nonlinearity of throw-out force and uncertainty in clutch wear. For precise position control of the clutch, this study proposes a control scheme using model predictive control method with the correction of clutch wear based on the estimation of resistance torque. First, a novel and detailed clutch model is introduced, mainly including a driven plate model and a diaphragm spring model. Next, through theoretical analysis of the clutch model and the experimental data of a real clutch, the characteristics of the nonlinear throw-out force are obtained with different clutch wear situations. Then, a reliable clutch actuator is designed, whose model is also built to analyze its dynamics. At last, an automatic clutch controller is designed, and in order to apply it in clutch control unit for real-time control, it is simplified to reduce the online computing burden. The results both of simulations and bench experiments show that the proposed control scheme has a satisfying control performance.
Salinity and alkalinity are among the important factors affecting the distribution, survival, growth and physiology of aquatic animals. Chinese sea bass (
) is an important aquaculture fish species ...in China that can widely adapt to diverse salinities from freshwater (FW) to seawater (SW) but moderately adapt to highly alkaline water (AW). In this study, juvenile
were exposed to salinity change (SW to FW) and alkalinity stress (FW to AW). Coordinated transcriptomic responses in
gills were investigated and based on the weighted gene co-expression network analysis (WGCNA), 8 and 11 stress-responsive modules (SRMs) were identified for salinity change and alkalinity stress, respectively, which revealed a cascade of cellular responses to oxidative and osmotic stress in
gills. Specifically, four upregulated SRMs were enriched with induced differentially expressed genes (DEGs) for alkalinity stress, mainly corresponding to the functions of "extracellular matrix" and "anatomical structure", indicating a strong cellular response to alkaline water. Both "antioxidative activity" and "immune response" functions were enriched in the downregulated alkaline SRMs, which comprised inhibited alkaline specific DEGs, revealing the severely disrupted immune and antioxidative functions under alkalinity stress. These alkaline-specific responses were not revealed in the salinity change groups with only moderately inhibited osmoregulation and induced antioxidative response in
gills. Therefore, the results revealed the diverse and correlated regulation of the cellular process and stress response in saline-alkaline water, which may have arisen through the functional divergence and adaptive recruitment of the co-expression genes and will provide vital insights for the development of
cultivation in alkaline water.
Background Hyperoxaluria and increased calcium oxalate stone formation occur after Roux-en-Y gastric bypass (RYGB) surgery for morbid obesity. The etiology of this hyperoxaluria is unknown. We ...hypothesized that after bariatric surgery, intestinal hyperabsorption of oxalate contributes to increases in plasma oxalate and urinary calcium oxalate supersaturation. Methods We prospectively examined oxalate metabolism in 11 morbidly obese subjects before and 6 and 12 months after RYGB ( n = 9) and biliopancreatic diversion-duodenal switch (BPD-DS) ( n = 2). We measured 24-hour urinary supersaturations for calcium oxalate, apatite, brushite, uric acid, and sodium urate; fasting plasma oxalate; 72-hour fecal fat; and increases in urine oxalate following an oral oxalate load. Results Six and 12 months after RYGB, plasma oxalate and urine calcium oxalate supersaturation increased significantly compared with similar measurements obtained before surgery (all P ≤ .02). Fecal fat excretion at 6 and 12 months was increased ( P = .026 and .055, 0 vs 6 and 12 months). An increase in urine oxalate excretion after an oral dose of oxalate was observed at 6 and 12 months (all P ≤ .02). Therefore, after bariatric surgery, increases in fecal fat excretion, urinary oxalate excretion after an oral oxalate load, plasma oxalate, and urinary calcium oxalate supersaturation values were observed. Conclusion Enteric hyperoxaluria is often present in patients after the operations of RYGB and BPD-DS that utilize an element of intestinal malabsorption as a mechanism for weight loss.
As lower vertebrates, teleost species could be affected by dynamic aquatic environments and may respond to environmental changes through the hypothalamus–pituitary–gonad (HPG) axis to ensure their ...normal growth and sexual development. Chinese sea bass (Lateolabrax maculatus), euryhaline marine teleosts, have an extraordinary ability to deal with a wide range of salinity changes, whereas the salinity decrease during their sex-maturation season may interfere with the HPG axis and affect their steroid hormone metabolism, resulting in abnormal reproductive functioning. To this end, in this study, 40 HPG axis genes in the L. maculatus genome were systematically characterized and their copy numbers, phylogenies, gene structures, and expression patterns were investigated, revealing the conservation of the HPG axis among teleost lineages. In addition, freshwater acclimation was carried out with maturing male L. maculatus, and their serum cortisol and 11-ketotestosterone (11-KT) levels were both increased significantly after the salinity change, while their testes were found to be partially degraded. After salinity reduction, the expression of genes involved in cortisol and 11-KT synthesis (cyp17a, hsd3b1, cyp21a, cyp11c, hsd11b2, and hsd17b3) showed generally upregulated expression in the head kidneys and testes, respectively. Moreover, cyp11c and hsd11b2 were involved in the synthesis and metabolism of both cortisol and 11-KT, and after salinity change their putative interaction may contribute to steroid hormone homeostasis. Our results proved the effects of salinity change on the HPG axis and steroidogenic pathway in L. maculatus and revealed the gene interactions involved in the regulation of steroid hormone levels. The coordinated interaction of steroidogenic genes provides comprehensive insights into steroidogenic pathway regulation, as well as sexual development, in teleost species.
Kidney stones are a risk factor for chronic kidney disease (CKD), which, in turn, is a risk factor for myocardial infarction (MI). The objective of this study was to determine whether kidney stones ...associate with an increased risk for MI. We matched 4564 stone formers (1984 through 2003) on age and gender with 10,860 control subjects among residents in Olmsted County, Minnesota. We identified incident MI by diagnostic codes and validated events by chart review through 2006. We used diagnostic codes to determine incidence of kidney stones and presence of comorbidities (CKD, hypertension, diabetes, obesity, dyslipidemia, gout, alcohol dependence, and tobacco use). During a mean of 9 years of follow-up, stone formers had a 38% (95% confidence interval 7 to 77%) increased risk for MI, which remained at 31% (95% confidence interval 2% to 69%) after adjustment for CKD and other comorbidities. In conclusion, kidney stone formers are at increased risk for MI, and this risk is independent of CKD and other risk factors.
We examined the effect of a controlled diet and two probiotic preparations on urinary oxalate excretion, a risk factor for calcium oxalate kidney stone formation, in patients with mild hyperoxaluria. ...Patients were randomized to a placebo, a probiotic, or a synbiotic preparation. This tested whether these probiotic preparations can increase oxalate metabolism in the intestine and/or decrease oxalate absorption from the gut. Patients were maintained on a controlled diet to remove the confounding variable of differing oxalate intake from food. Urinary oxalate excretion and calcium oxalate supersaturation on the controlled diet were significantly lower compared with baseline on a free-choice diet. Neither study preparation reduced urinary oxalate excretion nor calcium oxalate supersaturation. Fecal lactobacilli colony counts increased on both preparations, whereas enterococcal and yeast colony counts were increased on the synbiotic. Total urine volume and the excretion of oxalate and calcium were all strong independent determinants of urinary calcium oxalate supersaturation. Hence, dietary oxalate restriction reduced urinary oxalate excretion, but the tested probiotics did not influence urinary oxalate levels in patients on a restricted oxalate diet. However, this study suggests that dietary oxalate restriction is useful for kidney stone prevention.
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