The metabolic regulation mechanism of gallic acid on biogenic amines and nitrosamines in reduced-nitrite Chinese fermented sausages: A perspective of metabolomics and metagenomics.

Reducing nitrites tends to increase the accumulation of hazardous biogenic amines (BAs) in Chinese fermented sausages (CFSs). Gallic acid (GA) has emerged as a potential alternative to reduce nitrite usage and control BAs. This study explored how GA inhibits BAs and nitrosamines accumulation in reduced-nitrite CFSs. Results demonstrated that combining 0.05% (w/w) GA with reduced nitrite effectively curbed BAs and N-nitrosodimethylamine, decreasing total BA from 271.48 to 125.46 mg/kg. Fifty-one metabolites associated with the metabolism of BAs and N-nitrosodimethylamine were identified. GA boosted Lactococcus while reducing spoilage bacteria and Macrococcus. This dual regulation suppressed BAs and dimethylamine accumulation by regulating amino acids and trimethylamine pathways. Consequently, GA achieved an 89.86% reduction in N-nitrosodimethylamine by decreasing the key precursors like putrescine, dimethylamine, and nitrite. These findings offer new insights into utilizing GA and similar plant polyphenols to manage BAs and nitrosamines in meat products with reduced nitrite usage.

Preparation of a (Ca,Sr,Ba)ZrO3 Crucible by Slip Casting for the Vacuum Induction Melting of NiTi Alloy.

Vacuum induction melting is a more energy-efficient process for the preparation of a titanium alloy with good homogeneity and low cost. But the crucial problem for this technology is in developing a crucible refractory with high stability. In the present work, a novel (Ca,Sr,Ba)ZrO3 crucible was prepared by slip casting and its performance in melting NiTi alloy was studied. The results showed that a single solid solution was formed with a homogeneous distribution of metal elements after sintering at 1500 °C. It was found that the total content of oxygen and nitrogen remaining in the TiNi alloy after melting in the (Ca,Sr,Ba)ZrO3 crucible was 0.0173 wt.%, which fulfills the ASTM standard on biomedical TiNi alloys. The good resistance of the (Ca,Sr,Ba)ZrO3 crucible to molten NiTi has a relationship with the sluggish diffusion effect of high-entropy ceramics. This study provides insights into the process of designing highly suitable crucible material for melting a NiTi alloy.

Improved encapsulation effect and structural properties of whey protein isolate by dielectric barrier discharge cold plasma.

The whey protein isolate (WPI) was modified by dielectric barrier discharge cold plasma (DBD) in order to improve its encapsulation efficiency of rutin. In this work, the effect of DBD treatment on structure and physicochemical properties of WPI and the interaction between DBD-treated WPI and rutin were investigated. The results showed that the structural change of WPI leaded to the exposure of internal hydrophobic groups, increasing the interaction site with rutin. The encapsulation efficiency of DBD-treated WPI (30 kV, 30 s) on rutin was improved by 12.42 % compared with control group. The results of multispectral analysis showed that static quenching occurred in the process of interaction between DBD-treated and rutin, hydrogen bond and van der Waals force were the main forces between them. Therefore, DBD treatment can be used as a method to improve the encapsulation efficiency of WPI on hydrophobic active substances.

Rumen-protected lysine supplementation improved amino acid balance, nitrogen utilization and altered hindgut microbiota of dairy cows.

This study was conducted to evaluate the effects of dietary crude protein (CP) and rumen-protected lysine (RPL) supplementation on lactation performance, amino acid (AA) balance, nitrogen (N) utilization and hindgut microbiota in dairy cows. Treatments were in a 2 × 2 factorial arrangement, and the main effects were CP concentration (16% vs. 18%) and RPL supplementation (with or without RPL at 40 g/cow per day). Forty cows were randomly allocated to 4 groups: low-CP diet (LP), low-CP diet plus RPL (LPL), high-CP diet (HP), high-CP diet plus RPL (HPL). The experiment was conducted for 8 weeks. Results showed that RPL increased the dry matter intake (P < 0.01), milk protein yield (P = 0.04) and energy corrected milk (P = 0.04), and tended to increase milk fat yield (P = 0.06) and fat corrected milk (P = 0.05). Cows in the HP group tended to have higher milk urea N (P = 0.07). Plasma concentrations of Arg, Ile, Lys, Met, Pro, total essential AA and total nonessential AA were increased by RPL (P < 0.05). The total essential AA, total nonessential AA and most AA (except Ile, Phe, Gly and Pro) were increased in the HP group (P < 0.05). N excretion was increased in the HP group through an increase in urea N excretion (P < 0.01) and an upward trend in plasma urea N (P = 0.07). In addition, RPL tended to increase milk protein N secretion (P = 0.08), milk N (P = 0.07) and microbial protein synthesis (P = 0.06), and decreased plasma urea N (P < 0.001). In the hindgut, the bacterial community were different between the LP and LPL groups (P < 0.01). The probiotic abundances of Christensenellaceae_R-7_group and Acinetobacter were increased by RPL (P = 0.03 and 0.03, respectively). The pathogenic abundances of Clostridium_sensu_stricto_1 (P < 0.001) and Turicibacter (P < 0.01) were decreased by RPL. In conclusion, supplementing RPL with low dietary CP could balance AA supply and increase milk protein yield, resulting in an improvement in N utilization efficiency, and altered the composition of the hindgut microbiota to favor the lactation performance of dairy cows.

Design Strategies for Perovskite-Type High-Entropy Oxides with Applications in Optics.

It is essential and challenging to develop advanced ceramic materials with thermal stability and high reflectivity for optical fields. Encouragingly, recent breakthroughs and significant advances in high-entropy ceramics have made high-entropy oxides a potential candidate material for optical applications. Therefore, in this study, we analyzed the effect of lattice distortion on the design of high-reflectivity, high-entropy oxides using first-principles calculations and aberration-corrected microscopy. In order to optimize the optical properties of the materials, a series of novel perovskite-type high-entropy oxides, (LaxK0.4-xCa0.2Sr0.2Ba0.2)TiO3+δ (x = 0.1, 0.15, 0.2, 0.25, 0.3), were designed and synthesized using solid-state sintering based on the charge conservation principle and bond energy principle. When the content of La in the A-site element was 30%, the optical reflectivity reached 94% by suppressing the oxygen vacancy. Furthermore, we have successfully prepared a series of coatings by air spraying based on the regulation of the mass ratio of resin and powder. Compared to the uncoated substrate, the backside temperature can be reduced by 41%. This work provides a feasible design route with the first clear guidelines for highly reflective high-entropy ceramic materials and enables highly stable material design in multielement spaces.

Color stability and degradation kinetics of anthocyanins in mulberry stirred yoghurt fermented by different starter cultures.

To evaluate the storage stability of anthocyanin in stirred yoghurt, mulberry juice and different starter cultures (S) were added into milk to investigate the color stability and degradation kinetics of anthocyanin. The result showed that the redness value decreased, while the brightness value increased, and the anthocyanin content decreased significantly from 1.47 ~ 1.86 to 1.01 ~ 1.19 mg/g. The degradation kinetics followed a first-order reaction. Principal component analysis showed that S2 and S6 were correlated with anthocyanins, S8 and S4 were correlated with a*. At the later stage, S4, S8 were correlated with a*, while S2, S4, S6 were correlated with anthocyanins. At 28th day, the anthocyanin content of S4 was 1.14 mg/g, which was not the highest, but the total score was the highest. Therefore, S4 was the best choice when the storage period is 28 days. This study provided technical support for the selection of a better starter for stirring yoghurt. Supplementary Information: The online version contains supplementary material available at 10.1007/s10068-023-01271-8.

Intestinal Barrier Protective Study of Jujube Peel Polyphenols/Zein Complexes by a Combined Caco-2 Cell and Caenorhabditis elegans Model: A Perspective of Proteomics.

Jujube peels have been recognized as a promising resource of several bioactive ingredients. The main composition of jujube peel polyphenols (JPP) has been identified as rutin, kaempferol-3-O-rutinosid, and salicylic acid. The JPP/zein complexes, whose bioavailability reached 69.73% ± 5.06% in vitro, have been formed successfully. The Caco-2 cell and Caenorhabditis elegans (C. elegans) models have been combined to detect the intestinal barrier protective effect of JPP and its complexes. Results showed that JPP/zein complexes contain better protection capability than JPP in both models. In the Caco-2 cell model, the complex relieved intestinal barrier damage by regulating the tight junction proteins. Moreover, the lysosome pathway has been activated, further regulating immune responses and lipid transportation, improving the barrier function of C. elegans after incubation with JPP/zein complexes according to the proteomics study. This work provides new insights into intestinal barrier protection with bioactive compounds.

Thermal Stability, Optical and Electrical Properties of Substoichiometric Molybdenum Oxide.

Substoichiometric molybdenum oxide ceramics have aroused widespread interest owing to their promising optical and electrical performance. In this work, the thermal stability and decomposition mechanism of Mo9O26 and Mo4O11 at 700-1000 °C and 700-1100 °C were investigated, respectively. Based on this information, MoOx (2 < x < 3) bulk ceramics were prepared by spark plasma sintering (SPS). The results show that Mo9O26 is stable up to 790 °C in an argon atmosphere. As the temperature rises, it decomposes into Mo4O11. Mo4O11 can exist stably at 830 °C, beyond which it will convert to MoO2. The MoOx ceramic bulks with four different components (MoO2.9, MoO2.8, MoO2.7 and MoO2.6) were successfully sintered by SPS, and their relative density was greater than 96.4% as measured by the Archimedes principle. The reflectivity of MoOx ceramic bulk is low and only 6.3% when the composition is MoO2.8. The resistivity increases from 10-3 to 10-1 Ωcm with the increase in the O/Mo atomic ratio x. In general, the thermal stability information provides a theoretical basis for the processing of MoOx materials, such as the sintering of the MoOx target. The optical and electrical properties show that MoOx is a low-reflective conductive oxide material with great photoelectric application value.

Insight into the self-assembly behavior of α-zein by multi-spectroscopic and molecular simulations: An example of combination with the main component of jujube peel pigments - Rutin.

Zein has been widely used as a kind of carrier material for its self-assembly capability, while the mechanism of this process is still elusive. Rutin, one of the flavonoids, has been confirmed as the main ingredient of pigments in jujube peels. In this work, the binding mechanism in the zein/rutin complexes has been systematically studied by using multi-spectroscopic methods and molecular simulations. Results have shown that the encapsulation efficiency of complexes has researched the maximum, 67.30 % ± 1.50 %, when the concentration of rutin is 60 µM. Furthermore, the spherical morphology of complexes has been provided by microstructure characterization. Multi-spectroscopic indicated that a static quenching, alongside strong affinity, occurred in the process of interaction. Hydrophobic interaction has been further proven as the main force in zein/rutin complexes from the results of molecular dynamics simulation. This work is vital to fully utilize zein for the delivery of bio-compounds.

Effects of hydrogen peroxide and l-tryptophan on antioxidative potential, apoptosis, and mammalian target of rapamycin signaling in bovine intestinal epithelial cells.

Amino acids are primarily absorbed in the ruminant small intestine, and the small intestine is a target organ prone to oxidative stress, causing intestinal disfunction. Previous study suggested that l-Trp could benefit intestinal function and production performance. This study aimed to explore the effects of l-Trp on hydrogen peroxide (H2O2)-induced oxidative injury in bovine intestinal epithelial cells (BIEC) and the potential mechanism. The effects of l-Trp on cell apoptosis, antioxidative capacity, AA transporters, and the mammalian target of rapamycin (mTOR) signaling pathway were evaluated in BIEC treated with 0.8 mMl-Trp for 2 hours combined with or without H2O2 induction. In addition, to explore whether the effects of 0.8 mMl-Trp on oxidative stress were related to mTOR, an mTOR-specific inhibitor was used. The percentage of apoptosis was measured using flow cytometry. The relative gene abundance and protein expression in BIEC were determined using real-time PCR and Western blot assay, respectively. Results showed l-Trp at 0.4 and 0.8 mM enhanced the cell viability, and it was inhibited by l-Trp at 6.4 mM. l-Tryptophan at 0.4, 0.8, and 1.6 mM remarkably decreased the percentage of apoptosis and enhanced antioxidative capacity in H2O2-mediated BIEC. Moreover, l-Trp at 0.8 mM increased the relative gene abundance and protein expression of antioxidative enzymes and AA transporters, and the mTOR signaling pathway. The mTOR inhibitor lowered the protein expression of large neutral amino acid transporter 1, but the inhibition of mTOR did not alter the activities of catalase and superoxide dismutase or protein expression of alanine-serine-cysteine transporter 2 with or without H2O2 induction. l-Tryptophan increased catalase and superoxide dismutase activities in H2O2-mediated BIEC, although not with a present mTOR inhibitor. l-Tryptophan increased the protein expression of large neutral amino acid transporter 1 and alanine-serine-cysteine transporter 2 in H2O2-mediated BIEC with or without the presence of an mTOR inhibitor. The present work suggested that l-Trp supplementation could alleviate oxidative injury in BIEC by promoting antioxidative capacity and inhibiting apoptosis, and the mTOR signal played vital roles in the alleviation.

Proteomic analysis reveals the mechanism of green regulation in garlic puree induced by purple light stress.

Greening is an undesirable appearance in garlic puree during processing. Our previous study indicated that purple light could induce the greening changes in garlic. In order to investigate the mechanism of green regulation in garlic puree, purple light-induced greening and nongreening garlic puree were used as materials to investigate the differentially expressed proteins (DEPs) by sodium dodecyl-sulfate polyacrylamide gel electrophoresis and data-independent acquisition (DIA) technology. The results showed that a total of 186 DEPs were detected by DIA, with 73 DEPs were up-regulated in greening garlic puree and 113 of them were down-regulated in greening garlic puree. Most DEPs were belonged to 20 functional categories, and mainly participated in post-translational modification and transport of proteins, molecular chaperones (12.93%) and signal transduction mechanisms (10.20%), energy production and transformation (6.80%), carbohydrate transport and metabolism (5.44%) and amino acid transport and metabolism (4.08%), indicating that the biological metabolic pathway, metabolic direction, and metabolic strength efficiency significantly changed in garlic puree after greening. Besides, the physiological and biochemical experiments showed that purple light significantly induced the γ-glutathione transpeptidase activity and prompted the conversion of thiosulfinate into garlic green pigment. This study explained the general molecular mechanism of greening changes of garlic puree in response to purple light. Practical Application Greening is an undesirable appearance in garlic puree during processing, which deteriorate the qualities of garlic. This study provides a comprehensive understanding of green regulation in garlic puree based on proteomics analysis.

Enhanced extraction of bioactive natural products using ultrasound-assisted aqueous two-phase system: Application to flavonoids extraction from jujube peels.

The ultrasound-assisted aqueous two-phase extraction (UA-ATPE) was employed to develop an effective technique for the extraction of flavonoids from jujube peels (JPs). The extraction conditions were further optimized as K2HPO4 35% (w/w), ethanol 20% (w/w), solid-liquid ratio 1:30 g/mL (w/v), ultrasonic power 200 W, and extraction time 50 min. Moreover, rutin, quercetin 3-ß-d-glucoside, and kaempferol-3-O-rutinosid were identified as the main flavonoids by UPLC-MS/MS. Finally, the extraction mechanism of UA-ATPE was explored, which is salting out effect, hydrogen bonding, van der Waals force, and ultrasound promoted the mass transfer of solvent to cells of JPs, then extraction behavior occurred. The mechanical destruction of JPs cells by ultrasound also further accelerated the release of flavonoids. Flavonoids were captured by W/W emulsion in the bottom phase and distributed to the top phase. Overall, this study proposes a green and clean method, UA-ATPE, to extract flavonoids from JPs, while revealing the mechanism of UA-ATPE.

LncRNA NEAT1 promoted MPP+­induced ferroptosis via regulating miR­150­5p/BAP1 pathway in SK­N­SH cells.

As widely reported, dysregulated ferroptosis is closely associated with Parkinson's disease (PD) progression. The goal of the present study was to probe the roles of long non­coding RNA (lncRNA) nuclear enriched assembly transcript 1 (NEAT1) in regulating ferroptosis in PD. PD cell model was constructed by subjecting SK­N­SH cells to 1­methyl­4­phenylpyridinium (MPP+) for 24 h. The RNA levels of NEAT1, miRNA (miR)­150­5p, and BRCA1­associated protein 1 (BAP1) were evaluated using qRT­PCR. The protein levels of glutathione peroxidase 4 (GPX4), BAP1, and solute carrier family 7 member 11 (SLC7A11) were determined using western blot. Cell viability was assessed using 3­(4,5­dimethylthiazolyl2)­2, 5­diphenyltetrazolium bromide (MTT) assay. In addition, fluorescent probe 2,7­dichlorodihydrofluorescein diacetate (DCFH­DA) was employed to determine the ROS level. Moreover, the levels of GSH, MDA, and Fe2+ were also measured. Finally, the interactions among NEAT1, miR­150­5p, and BAP1 were identified by dual luciferase reporter gene assay, and/or RIP assay. Upregulated NEAT1 was observed in PD cell model. Knockdown of NEAT1 elevated viability and GSH level in PD cell model and reduced ROS, MDA, and Fe2+ levels. Moreover, NEAT1 functioned as a sponge to suppress miR­150­5p expression. Moreover, miR­150­5p overexpression suppressed ferroptosis in PD cell model. We subsequently found that miR­150­5p regulated SLC7A11 expression by directly binding to BAP1. miR­150­5p inhibition or BAP1 overexpression mitigated the anti­ferroptosis effect meditated by sh­NEAT1. Taken together, knockdown of NEAT1 mitigated MPP+­induced ferroptosis through regulating BAP1/SLC7A11 axis by sponging miR­150­5p, indicating the potential of NEAT1 as a promising therapeutic target for PD.

Heavy Mn-doped CsPbBr3nanocrystals synthesized by high energy ball milling with high stability.

CsPbX3(X = Cl, Br, I) semiconductor nanocrystals (NCs) have excellent optical and photoelectric properties, and are potential core materials for various photoelectric devices. However, the toxicity of Pb and instability have been the key limitations to application of NCs. Herein, using MnBr2and MnBr2·4H2O as manganese sources, heavy Mn-doped CsPbBr3(Mn:CsPbBr3) NCs are synthesized by high-energy ball grinding, which avoids high temperature, a large number of polar solvents and atmosphere protection required in traditional liquid phase methods. However, when MnBr2·4H2O is used as the raw material, infinite solid solution doping can be achieved, and the synthesized Mn:CsPbBr3NCs show smaller particle size, stronger PL intensity and stability. The reason is that presence of crystal water plays a similar role to wet milling in the ball milling process, and can promote the passivation effect of oleylamine (OAm) on nanocrystal defects and the connection between them. In addition, a simple, easy-operating and beneficial to commercial production method for the preparation of Mn:CsPbBr3NCs/EVA flexible films is proposed, which can effectively improve the stability of Mn:CsPbBr3NCs. This study is expected to provide an effective way for the synthesis and stability improvement of CsPbX3NCs doped with different ions.

Jujube peel polyphenols synergistically inhibit lipopolysaccharide-induced inflammation through multiple signaling pathways in RAW 264.7 cells.

Jujube has great potential as food and traditional drugs in several countries. To study the anti-inflammatory influence of jujube peel polyphenols in lipopolysaccharide (LPS) induced RAW 264.7 cells through mitogen-activated protein kinase (MAPK), nuclear factor-kappa B (NF-κB) and nuclear erythroid 2-related factor 2 (Nrf2) signaling pathways. In this study, the phenolic composition of polyphenols in jujube peel was analyzed using LC-MS/MS, and which was confirmed that the main polyphenols were p-coumaric acid, catechin and rutin. Meanwhile, jujube peel polyphenols attenuated the generation of TNF-α, IL-1ß, IL-6, NO and PGE2 by inhibiting MAPK and NF-κB signaling pathways. Additionally, jujube peel polyphenol activate Nrf2 from the cytoplasm to the nucleus, regulate antioxidant enzymes and pro-inflammatory cytokines, and reduce oxidative stress and inflammatory responses. Results obtained from this study suggest that jujube peel polyphenols may alleviate oxidative stress and inflammation by inhibiting MAPK and NF-κB and activating Nrf2 signaling pathways. Furthermore, jujube peel polyphenols have a synergistic effect in the treatment of LPS-induced inflammatory in RAW 264.7 cells. In conclusion, this study not only reveals the mechanism by which jujube peel polyphenols inhibit LPS-induced inflammation in RAW 264.7 cells, but also provides guidance for the development of new anti-inflammatory drugs.

Ultrasound-assisted adsorption/desorption of jujube peel flavonoids using macroporous resins.

The work explored the process of ultrasound-assisted adsorption/desorption to efficiently purify jujube peel flavonoids (JPFs) using macroporous resins (MRs). The impact of ultrasound power and temperature on the adsorption/desorption features of JPFs on MRs were studied. The maximum adsorption (80.21 ± 2.11 mg/g) /desorption (76.22 ± 1.68 mg/g) capacity of total flavonoids content were obtained. The pseudo-second-order kinetic and Freundlich isotherm models better described the whole process of ultrasound-assisted adsorption. The adsorption process was spontaneous, physical, and dominated by multilinear intraparticle diffusion. Ultrasound mainly enhanced the adsorption capacity by strengthening the formation of hydrogen bonds and increasing the surface roughness of MRs. Besides, the principal individual flavonoid ((+)-Catechin, (-)-Epicatechin, Rutin, Quercetin-3-O-robinobioside) content of JPFs in ultrasound treatment was 2-3 times that of shaking treatment, and biological activities were significantly increased. Overall, as a low-cost green technology, ultrasound can improve the properties of MRs and better purify JPFs.

Age-dependent alteration in metabolism of vitamin B6 , neurotransmitters, and amino acids after 4'-O-methylpyridoxine administration in rats.

4'-O-methylpyridoxine (MPN), a recognized antivitamin B6 compound, is a potentially poisonous substance found in Ginkgo biloba L. In this work, the effects of MPN on the metabolism of vitamin B6 , neurotransmitters, and amino acids were compared in the plasma and brain of young and adult rats under various administration times. Results showed that the contents of MPN residues in the plasma and brain of young rats were 12.72 and 14.76 µM higher than adult rats, respectively. Moreover, the levels of 5-hydroxytryptamine and dopamine in the brain of young rats have decreased by 13.78% and 7.19%, respectively, compared with the control group, at 2 h after MPN administration. Furthermore, the principal component analysis revealed that MPN was an important contributor to the amino acid composition in the brain of young rats. These results suggest that age may lead to different toxic effects of MPN. PRACTICAL APPLICATION: 4'-O-methylpyridoxine is primarily responsible for poisoning due to overconsumption of Ginkgo biloba seeds. This study will provide an exploratory understanding of the age-dependent toxicity of 4'-O-methylpyridoxine.

In vivo toxicity assessment of 4'-O-methylpyridoxine from Ginkgo biloba seeds: Growth, hematology, metabolism, and oxidative parameters.

4'-O-methylpyridoxine (MPN), a recognized antivitamin B6 compound, is a potentially poisonous substance found in Ginkgo biloba seeds and leaves. In this work, the body weights, histopathological changes, plasma vitamin B6 (VB6), biochemical parameters, oxidative stress responses, and amino acids of rats were investigated after intragastric administration of MPN for 15 days. Results showed that intragastric administration of 50 mg/kg BW MPN caused pathological changes in the brain and heart tissues of rats. Administration of 10 mg/kg and 30 mg/kg BW MPN can significantly increase VB6 analogs in the plasma of rats, such as pyridoxal-5'-phosphate, pyridoxal. Results of biochemical parameters indicated that MPN can damage brains and hearts by changing the enzyme activity of these organs. These results suggest that consumption of Ginkgo biloba seeds for the long term, even in a small quantity, may lead to poisoning.

A highly durable CoOx/N-doped graphitized-nano-diamond electrocatalyst for oxygen reduction reaction.

Oxygen reduction reaction (ORR) occupies a pivotal position in fuel cell applications, and it is a challenge to obtain highly durable ORR catalysts. Herein, porous cobalt oxide microsphere growing at the surface of on nitrogen-doped graphitized-nano-diamond (CoOx/N-GND) was prepared using hydrothermal and subsequent heat treatment process. Porous cobalt oxide of high specific surface area could expose more surface Co2+that act as active sites than bulk one does. The doping of nitrogen also promotes the catalytic activity. Besides, nano-diamond (ND) ofsp3hybrid structure was used as an electronic conduction carriers of ultrahigh stability to improve the durability of catalytic composite. Prepared CoOx/N-GND shows a satisfactory half-wave potential of 0.82 V (versus RHE), which is close to that of Pt/C (0.85 V), an excellent methanol tolerance and a lower activity loss after 5000 cycles. These merits inspire the application of CoOx/N-GND as the cathode of Zn-air battery and the battery performance was evaluated in this work. In general, this work highlights an innovate approach to design and prepare highly durable catalyst.