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In view of problems that there are frequency and phase errors in extracting voltage synchronization signals of DSOGI-PLL with multiple harmonics or DC bias in mine grid, an improved DSOGI-PLL was proposed to improve DSOGI-PLL from three aspects: frequency regulation, DC bias and harmonic detection.Frequency adaptive adjustment unit is constructed to automatically adjust resonant frequency of DSOGI-PLL through real-time monitoring of frequency change of mine power grid, so as to realize frequency adaptive function of DSOGI-PLL, which can improve accuracy of frequency detection and optimize dynamic response performance.Integral feedback compensation is applied to the second-order generalized integrator-quadrature signals generator(SOGI-QSG) to remove the influence of direct-current component on the test results.Cross feedback structure of multiple DSOGIs in parallel is proposed. In this structure, the input signal of each DSOGI does not contain harmonic components detected by other DSOGIs, which weakens influence of each harmonic component on each other. Matlab simulation results show that the improved DSOGI-PLL can complete accurate detection and tracking lock of frequency and phase angle of the grid voltage when the mine grid voltage has serious interference.

Low Pt utilization and intense carbon corrosion of cathode catalysts is a crucial issue for high‐efficiency proton exchange membrane fuel cells due to the highly demanded long‐term durability and less acquisition/application cost. Herein, structurally tunable graphitized mesoporous carbon (GMC) is obtained by direct high‐temperature pyrolysis and in situ‐controlled mesopore formation; the structure‐optimized GMC1300‐1800 exhibits a mesopore size of 7.54 nm and enhanced corrosion resistance. Functionalized GMC1300‐1800 is loaded with small‐sized Pt nanoparticles (NPs) (1.5 nm) uniformly by impregnation method to obtain Pt/GMC1300‐1800 and form an "internal platinum structure" to avoid sulfonic acid groups poisoning as well as ensure O2/proton accessibility. Hence, the electrochemically active surface area (ECSA) of Pt/GMC1300‐1800 reaches 106.1 m2 g−1Pt, while mass activity and specific activity at 0.9 V are 2.1 and 1.4 times those of commercial Pt/C, respectively. Notably, the ECSA decay is less than 17% for both 30 000 cycles' accelerated durability tests (ADTs) of Pt attenuation and carbon attenuation. Accordingly, the optimized mesoporous structure of GMC1300‐1800 significantly decreases the coverage of sulfonic acid groups on Pt NPs, leading to the highest peak power density in the single‐cell test. Density functional theory calculations demonstrate the synergistic effect between graphitization and mesoporosity on enhancing the accessibility and durability of the catalysts. [ABSTRACT FROM AUTHOR]

An 8-week growth trial was conducted to evaluate the effects of dietary arginine (Arg) levels on growth, gut morphology, oxidation resistance and immunity of hybrid grouper (Epinephelus fuscoguttatus ♀ ×Epinephelus lanceolatus ♂) juveniles. Seven isoenergetic (1465 kJ (350 kcal)/100-g DM), isoproteic (53·5 % of DM) and isolipidic (7 % of DM) experimental diets were formulated to contain graded Arg levels ranging from 1·9 to 4·7 % (dry weight) at approximately 0·5 % increments. Each diet was randomly assigned to triplicate groups of 16 juvenile fish (average initial body weight: 11·7 (sd 0·1) g) and was administered twice daily (08.00 and 16.00 hours). After the growth trial, all remaining fish were fed their prescribed diets for 2 d and then exposed to 4·5 mg Cu2+/l water for 36 h. Results showed that growth performance and feed utilisation of experimental fish were significantly affected by different dietary Arg levels. Weight gain % (WG%) of fish was increased as dietary Arg increased, reaching a peak value at 3·8 % dietary Arg level, and when dietary Arg level increased to 4·7 % WG% was reduced. Fish fed 1·9 and 2·2 % dietary Arg levels had higher daily feed intake compared with fish fed other dietary Arg levels. Feed conversion ratios in fish fed 1·9, 2·2, 2·7 and 4·7 % dietary Arg levels were higher than those in fish fed 3·1, 3·8 and 4·1 % dietary Arg levels. Protein efficiency ratio and protein productive value (PPV) increased with an increase in dietary Arg, up to a peak value at 3·8 % dietary Arg level, above which these parameters declined. On the basis of quadratic regression analysis of weight gain % (WG%) or PPV against dietary Arg levels, the optimal dietary Arg requirement for hybrid grouper was estimated to be 3·65 %. Fish fed 3·8 % dietary Arg had higher whole-body and muscle protein contents compared with fish fed other dietary Arg levels. Fish fed 3·8 and 4·1 % dietary Arg levels had higher levels of mRNA for insulin-like growth factor-I and target of rapamycin in the liver compared with fish fed other dietary Arg levels. Hepatic S6 kinase 1 mRNA expression in fish fed 3·8 % dietary Arg level was higher than that in fish fed any of the other dietary Arg levels. Gut morphology, hepatic antioxidant indices and immune indices in serum and head kidney were significantly influenced by dietary Arg levels. In conclusion, the optimal dietary Arg requirement for hybrid grouper was estimated to be 3·65 %, and suitable dietary Arg supplementations improved gut morphology and oxidation resistance of hybrid grouper. [ABSTRACT FROM AUTHOR]

Aim: Chondrosarcoma is difficult to treat because of resistance to conventional chemotherapy and radiotherapy. This study evaluated the effects of ethanol in combination with doxorubicin in chondrosarcoma cells.Materials& Methods: JJ012, was treated with doxorubicin alone or in combination with ethanol. Effects on cellular proliferation, migration, invasion, apoptosis, and the cell cycle were evaluated.Results: Treatment of JJ012 cells with 100 mM ethanol and doxorubicin resulted in reduced cell growth, invasion, and migration. In addition, doxorubicin uptake into the nucleus was enhanced and p53 mRNA expression was upregulated in JJ012 cells.Conclusion: Ethanol combined with doxorubicin increased doxorubicin uptake in the nucleus and enhanced the effects of doxorubicin in JJ012 cells. [ABSTRACT FROM AUTHOR]

An 8-week growth trial was conducted to study the effects of different corn starch levels on growth and feed utilization of juvenile hybrid grouper (male Giant GrouperEpinephelus lanceolatus× female Brown-marbled GrouperE. fuscoguttatus). Five isonitrogenous (48% crude protein, dry weight basis) and isolipidic (10% crude lipid, dry weight basis) diets were formulated to contain 0, 7, 14, 21, or 28% corn starch, respectively. Each dietary treatment had three replicates. Groups of 22 hybrid grouper juveniles (average initial weight, 2.74 g/fish) were stocked into small floating cages (120 cm long × 70 cm wide × 50 cm high). Triplicate groups of fish were fed each dietary treatment twice daily (0800 and 1600 hours) to apparent satiation. Water quality was monitored daily. Weight gain (WG) of hybrid grouper displayed no significant differences among all experimental groups. Fish fed 0% corn starch had significantly higher daily protein intake than fish fed 7, 14, 21, and 28% corn starch. The feed conversion ratio (FCR) and daily feed intake (FI) were significantly higher in fish fed diets with 0% corn starch, but FCR and FI were not observed to vary among fish fed any of the other experimental diets. Fish fed 0% corn starch had a lower protein efficiency ratio (PER) than fish fed other experimental diets, and the differences were significant when compared with fish fed 21% or 28% corn starch. Intraperitoneal fat (IPF) ratios did not show significant variations among all experimental treatments. The hepatosomatic index (HSI) of fish fed 0% corn starch were significantly lower than that of fish fed 14, 21, and 28% corn starch. Whole-body moisture, protein, lipid, and ash contents as well as muscle moisture, protein, and lipid contents showed no significant differences among all experimental groups. Hepatic glycogen content increased as dietary corn starch level increased. Fish fed the diet with no corn starch had more protein content in the liver than fish fed 14, 21, or 28% corn starch. Generally, supplementations of 7–28% dietary corn starch could reduce dietary protein input and improve feed utilization of hybrid grouper without negatively affecting their growth. Received May 22, 2015; accepted December 1, 2015 [ABSTRACT FROM PUBLISHER]

For the phenomenon that currently the calculations of the health protection zone and the atmospheric environment protection zone co -- existed in petrochemical enterprises, this paper compared their calculation methods, principles implementation etc., and analyzed the deficiencies and limitations of the standards for both zone's calculations. With a fertilizer plant for example, and choosing NH3 as the characteristic pollutants, the health protection zone and atmospheric environment protection zone was calculated respectively in this paper. The result showed that the health protection zone was 600 m calculated by the standard method and 400 m by the formula method. However, the health protection zone was 450 m calculated by the atmospheric environment protection zone calculation model. Based on the theory concentration of NH3 which were calculated by AER-MOD model in three zones, the optimum health protection one should be 450 m. It was verified by on -- site monitoring data that the reasonable protective zone was 450 m. It is more scientific and reasonable to calculate the health protection zone by atmospheric environment protection zone calculation model for petrochemical enterprises. [ABSTRACT FROM AUTHOR]

Acidic seawater electrolysis offers significant advantages in high efficiency and sustainable hydrogen production. However, in situ electrolysis of acidic seawater remains a challenge. Herein, a stable and efficient catalyst (SPTTPAB/IrO 2 ) is developed by coating iridium oxide (IrO 2 ) with a microporous conjugated organic framework functionalized with sulfonate groups (-SO 3 H) to tackle these challenges. The SPTTPAB/IrO 2 presents a -SO 3 H concentration of 5.62 × 10 -4  mol g -1 and micropore below 2 nm numbering 1.026 × 10 16  g -1 . Molecular dynamics simulations demonstrate that the conjugated organic framework blocked 98.62% of Cl - in seawater from reaching the catalyst. This structure combines electron conductivity from the organic framework and proton conductivity from -SO 3 H, weakens the Cl - adsorption, and suppresses metal-chlorine coupling, thus enhancing the catalytic activity and selectivity. As a result, the overpotential for the oxygen evolution reaction (OER) is only 283 mV@10 mA cm -2 , with a Tafel slope of 16.33 mV dec -1 , which reduces 13.8% and 37.8% compared to commercial IrO 2 , respectively. Impressively, SPTTPAB/IrO 2 exhibits outstanding seawater electrolysis performance, with a 35.3% improvement over IrO 2 to 69 mA cm -2 @1.9 V, while the degradation rate (0.018 mA h -1 ) is only 24.6% of IrO 2 . This study offers an innovative solution for designing high-performance seawater electrolysis electrocatalysts., (© 2024 The Author(s). Advanced Science published by Wiley‐VCH GmbH.)

Purpose: Optic nerve head (ONH) atrophy is frequently associated with hydrocephalic conditions. Cerebrospinal fluid (CSF)-containing meninges form a subarachnoid space that terminates at the ONH, which physically impacts it. This study aims to characterize optic neuropathy in congenital hydrocephalic mice with genetic disruption of the Ccdc13 gene., Methods: The ccdc13 germline knockout mice were generated. The hydrocephalus phenotype and subarachnoid space surrounding the optic nerve were evaluated using routine histology and Evans blue stain. Optic neuropathy was examined with immunohistochemistry and transmission electron microscopy (TEM). Axon transport was indicated by cholera toxin subunit B (CTB) fluorescence conjugate. Retinal function was evaluated by electroretinography (ERG), and Ccdc13 expression was revealed by a knock-in Gfp reporter., Results: Ccdc13 mutant mice manifested hydrocephalus at birth. ONH displacement, or negative cupping, and enlarged subarachnoid space at the optic terminus occurred as early as 1 month after birth. Intraocular pressure (IOP) was normal. Optic neuropathy was first observed at the ONH, followed by a distal-to-proximal progression of optic nerve pathology indicated by alteration of axonal ultrastructure and deposition of unphosphorylated neurofilament heavy chain. Anterograde axonal transport was also hampered. Retinal ganglion cell (RGC) function was compromised as early as postnatal day 21 (P21), along with reduced neurofilament heavy chain expression. Optic neuropathy caused by disruption of Ccd13 was non-cell autonomous, stemming from hydrocephalus with presumed high intracranial pressure (ICP), which physically impacts the ONH by increasing the translaminar pressure gradient., Conclusions: We provided knowledge of optic neuropathy from a congenital mouse model for hydrocephalus. The hydrocephalus in mice could damage the ONH by increasing the translaminar pressure gradient and negative cupping, leading to impairment in axoplasmic transport and RGC pathology. Our findings highlight the importance of the interplay between IOP and ICP in the development of glaucoma.