Superwetting Ag/α-Fe_(2)O_(3) anchored mesh with enhanced photocatalytic and antibacterial activities for efficient water purification

Superwetting materials have drawn unprecedented attention in the treatment of oily wastewater due to their preferable anti-fouling property and selective oil/water separation.However,it is still a challenge to fabricate multifunctional and environmentally friendly materials,which can be stably applied to purify the actual complicated wastewater.Here,a Ag/Ag/α-Fe_(2)O_(3) heterostructure anchored copper mesh was intentionally synthesized using a facile two-step hydrothermal method.The resultant mesh with superhydrophilicity and underwater superoleophobicity was capable of separating various oil/water mixtures with superior separation efficiency and high permeationflux driven by gravity.Benefiting from the joint effects of the smaller band gap of Ag/α-Fe_(2)O_(3) heterojunction,inherent antibacterial capacity of Ag/α-Fe_(2)O_(3) and Ag nanoparticles,favorable conductive substrate,as well as the hierarchical structure with superwettability,such mesh presented remarkably enhanced degradation capability toward organic dyes under visible light irradiation and antibacterial activity against both Escherichia coli(E.coli)and Staphylococcus aureus(S.aureus)compared with the pure Ag/α-Fe_(2)O_(3) coated mesh.Impressively,the mesh exhibited bifunctional water purification performance,in which organic dyes were eliminated simultaneously from water during oil/water separation in onefiltration process.More importantly,this mesh behaved exceptional chemical resistance,mechanical stability and long-term reusability.Therefore,this material with multifunctional integration may hold promising potential for steady water purification in practice.

Semisynthetic Derivatives of Sissotrin Isolated from Trifolium baccarinii Chiov. (Fabaceae) and Evaluation of Their Antibacterial Activities

Starting from sissotrin (1), a natural isoflavonoid isolated from Trifolium baccarinii (Fabaceae), one new semisynthetic derivative, 6-nitrobiochanin A (1b) and two known derivatives, 8-nitrobiochanin A (1a) and 2",3",4",6"-tetraacetylsissotrin (1c) have been obtained after performing nitration and acetylation reactions. Their structures were assigned after interpretation of their spectrometric (HR-ESI-MS) and spectroscopic (NMR 1D and 2D) data and by comparison with those reported in the literature. The substrate as well as the semisynthetic derivatives were evaluated for their antibacterial activities against six strains. The results reveal that they are inactive or weakly active on the strains tested with the exception of 8-nitrobiochanin A (1a) which showed moderate activity (MIC = 62.5 μg∙mL−1) on Staphylococcus aureus ATCC 43300.

Antioxidant,Anti-inflammatory,and Antibacterial Activities of Different Extracts from Polygonum capitatum

[Objectives]To investigate the antioxidant,anti-inflammatory and antibacterial activities of different extracts(aqueous,ethanol,ethyl acetate and n-butanol extracts)of Miao medicine Polygonum capitatum.[Methods]Eleven batches of P.capitatum in Guizhou province were collected,and water,ethanol,ethyl acetate and n-butanol extracts were prepared by reflux extraction.Antioxidant activity was determined by radical scavenging capacity of 1,1 diphenyl-2-picyl hydrazine(DPPH),anti-inflammatory activity was screened by lipopolysaccharide(LPS)induced RAW264.7 cells to produce NO,and the minimum inhibitory concentration(MIC)was screened by broth microdilution method.[Results]When the concentration of ethyl acetate extract was 10 mg/L,the scavenging rate of DPPH ranged from 90%to 99%.The(MIC of the ethyl acetate extract against Staphylococcus aureus(SA),Pseudomonas aeruginosa(PA)and Escherichia coli(EC)was 0.18-0.65,0.13-0.82,and 0.15-0.78 g/L,respectively.In the anti-inflammatory activity,ethyl acetate extract inhibited NO production with inhibition rate of 70%.[Conclusions]The ethyl acetate extract and ethanol extract of Miao medicine P.capitatum have strong antioxidant,anti-inflammatory and antibacterial activities.

Synthesis and in vitro antibacterial activities of 7-(4-alkoxyimino-3-hydroxypiperidin-1-y1)quinolone derivatives

A series of novel 7-(4-alkoxyimino-3-hydroxypiperidin-1-yl)quinolone derivatives were designed,synthesized and evaluated for in vitro antibacterial activities.Compounds 8f,8g,8i and 8j with the potencies similar to or better than those of levofloxacin and IMB against Staphylococcus aureus and Staphylococcus epidermidis,worth further investigation.

Syntheses,Crystal Structures and Antibacterial Activities of Schiff Base of Nickel(Ⅱ)and Copper(Ⅱ)Complexes

A new kind of Schiff base HL(HL= 1-phenyl-3-methyl-4-(p-methylbenzoyl)-5-pyrazolone with L-Leucine methyl ester) and complexes Ni L′_2·0.75C_2H_5OH·0.25H_2O,Cu L′′2(L′ = 1-phenyl-3-methyl-4-(p-methylbenzoyl)-5-pyrazolone with L-leucine ethyl,L′′ = 1-phenyl-3-methyl-4-(p-methylbenzoyl)-5-pyrazolone with L-leucine) have been synthesized and structurally determined by X-ray diffraction. For HL: crystal structure determination indicates that there are two independent HLs with different conformations in one asymmetric unit. For complex 1: the Ni(Ⅱ) ion is six-coordinated by two carbonyl oxygen atoms from pyrazolone ring,two nitrogen atoms from different HL′ and two oxygen atoms from L-Leucine ethyl ester to form a distorted octahedral geometry. For complex 2: the Cu(Ⅱ) ion is four-coordinated by one carbonyl oxygen atom from the pyrazolone ring,one nitrogen atom from HL′′,and two different carboxylic oxygen atoms from L-leucine with the same conformation to form a distorted quadrilateral geometry.

Synthesis, Crystal Structure, Antibacterial Activities and Theoretical Computation of 3-(2-Hydroxybenzly)-4-(4-isopropylbenzyl- ideneamino)-(1H)-1,2,4-triazole-5-thione

The title compound C18H18N4OS has been synthesized by the reaction of 3-(2-hydroxy- benzyl)-4-amino-(1H)-1,2,4-triazole-5-thione with 4-isopropylbenzaldehyde in ethanol and characterized by IR, 1H NMR spectra and elemental analysis. Its structure was determined by X-ray diffraction analysis. The crystal belongs to monoclinic, space group P21/c with a = 11.605(2), b = 7.401(1), c = 20.339(2) A, β = 103.05(2)°, V = 1701.8(4) ·3, Z = 4, Mr = 338.42, μ = 0.202 mm-1, Dc = 1.321 g/cm3 and F(000) = 712. The structure was solved by direct methods and refined to R = 0.0428 and wR = 0.1069. Due to the intramolecular O–H···N hydrogen bond and π-π stacking interactions between the benzene (C(1)～C(6)) and triazole rings, the two planes are essentially coplanar. Their biological activities have been measured, showing this type of compound has certain antibacterial activity for Staphylococous aureus and Bacillus subtilis. Based on the quantum chemistry calculation at the RHF/6-31G level, the frontier orbitals and electrostatic potential of the title compound were also discussed.

A New Ceramide (Rumexamide) and Other Chemical Constituents from <i>Rumex abyssinicus</i>Jacq (Polygonaceae): Isolation, Characterization, Antibacterial Activities and Chemophenetic Significance

The chemical study of Rumex abyssinicus Jacp (Polygonaceae) led to the isolation of a new ceramide named (R)-2'-hydroxy-N-[(2S,3S,4R,16E)-1,3,4-trihydroxyhexacos-16-en-2-yl]hexadecanamide (rumexamide) (1) together with sixteen known compounds: bis-(2-ethylhexyl) phthalate (2), chrysophanol (3), physcion (4), citreorosein (5), emodin (6), chrysophanein (7), physcionin (8), lupeol (9), 3β,28-dihydroxylup-20(29)-ene (10), 3β-dihydroxylup-20(29)-en-28-oic acid (11), oleanolic acid (12), ergosta-6,22-diene-3,5,8-triol (13), stigmastane-3,6-dione (14), a mixture of β-sitosterol (15) and stigmasterol (16), and stigmasterol 3-O-β-D-glucoside (17). Their structures were determined by interpretation of their spectroscopic 1D NMR (1H and 13C NMR), 2D NMR (COSY 1H-1H, HSQC and HMBC) data in conjunction with mass spectrometry (TOFESIMS and HR-TOFESIMS) and by comparison with those reported in the literature. Among all the known compounds, twelve (2, 5, 8-17) were firstly isolated from Rumex abyssinicus, seven (2, 10-14 and 17) from the genus Rumex and three (13, 14, 17) from family Polygonaceae. The in vitro antibacterial activities of extracts (MeOH, n-BuOH and EtOAc), as well as compounds 9, 11, 12, 15 + 16 and 17 against pathogenic bacteria (Staphylococcus aureus ATCC 43300, Shigella flexneri NR 518, Klebsiella pneumoniae ATCC 700603, Escherichia coli ATCC 25922), were performed using the broth microdilution method and the results show that, extracts were not active (MIC > 1000 μg/mL) while compounds were weakly or not active (MIC ≥ 500 μg/mL) against all bacteria strains. Furthermore, the chemophenetic relationships of the isolated compounds and their significances were discussed.

Synthesis, Characterization and Antibacterial Activities of Polydentate Schiff Bases, Based on Salicylaldehyde

Three Schiff bases L1, L2 and L3 were synthesized by condensing salicylaldehyde with 4-aminoantipyrine, ethylendiamine and 2-aminophenol respectively and subsequently characterized by various physicochemical investigations. All the three compounds were screened for their In-vitro antibacterial activity against two gram positive bacteria, Staphylococcus aureus (S.A), Staphylococcus epidermidis (S.E) and two gram negative bacteria Klebsiella pneumoniae (K.P) and Pseudomonas aeruginosa (P.A) by agar diffusion method. On comparing the results obtained with the activity of commercially available antibiotics such as Ciprofloxacin and Chloramphenicol, the newly synthesized compounds showed comparable antibacterial activities. The solvent methanol exhibit activity against all bacterial species with IZs ranging from 8 ± 0.25 to 17 ± 0.29 mm while the standard antibiotics Ciprofloxacin and Chloramphenicol exhibited an activities with IZs varying from 21.3 ± 0.31 to 28.3 ± 0.32 and 26.3 ± 0.24 mm to 32.3 ± 0.23 mm, respectively. However, the newly synthesized Schiff bases L1, L2 and L3 showed IZs ranging from 7.4 ± 0.23 to 32.5 ± 0.14, 3 ± 0.57 to 12 ± 0.28 and 10 ± 0.20 to 32 ± 0.36 respectively. Among the Schiff bases, L3 showed the activity (32 ± 0.36) against S.E and P.A which is higher than the activity of standard antibiotics Ciprofloxacin and Chloramphenicol against the same bacterial strains. The results obtained revealed that all the synthesized Schiff bases exhibit appreciable antibacterial activity against all the bacteria species which potentially makes them, to apply as wide range antibacterial drugs, after further in-vivo cytotoxicity investigations. Their activity can also be further modified by changing the functionality of precursors for Schiff base condensation.

Synthesis and Antibacterial Activities of New 2-(Benzylthio)pyrimidines and 2-(Benzimidazolylmethylthio)pyrimidines Derivatives

A series of 2-(benzylthio)pyrimidines (6a-l) and 2-(benzimidazolylmethylthio)-pyrimidines derivatives (6m and 6n) analogues of ethyl 2-(benzylthio)-6-methyl-4-phenyl-1,4-dihydropyrimidine-5-carboxylates and ethyl 2-(((1H-benzimidazol-2-yl)methyl)thio)-6-methyl-4-phenyl-1,4-dihydropyri-midine-5-carboxylates were prepared and evaluated for antibacterial activity. These compounds were obtained by condensation of 2-thiopyrimidines (4) with benzyl halides or 2-(chloromethyl)-1H-benzimidazole (5) in the presence of a base. All compounds were characterized by 1H, 13C and HRMS spectra. Out of fourteen, only eight compounds were screened against multi-resistant strains of Escherichia coli and Staphylococcus aureus. The results revealed that all of them were found to possess significant antibacterial activity against the germs tested. Compounds 6c, 6d, 6h and 6m were more active on S. aureus and compounds 6h and 6m more active on E. coli.

Antibacterial Activities of the Ethanolic Extract of <i>Crateva adansonii</i>DC. (Capparidaceae) Harvested in Dassa-Zoumèin Central Bénin

Objective: The present was initiated to study the antibacterial properties of the Crateva adansonii DC extract on germs commonly identified in skin and digestive infections in Benin as well as the reversion of resistance to these aforementioned germs. Method: The bacteria’s sensitivity test to extracts was carried out by the microdilution method in liquid medium as well as the MIC and the reversion of bacterial resistance. For the determination of the MBC, this technique is used coupled with spreading on agar medium. Results: The results show an antibacterial activity of the extract with MICs between 0.625 - 5 mg/ml. The CMB of Enterococcus faecalis ATCC 29212 is 2.5 mg/ml while that of Methicillin-resistant Staphylococcus aureus and Staphylococcus epidermidis CIP 8039 is 5 mg/ml. The reversion of bacterial resistance has shown a synergy of action between our extract and conventional antibiotics.

Antibacterial Activities of <i>Psidium guajava</i>(Guava) and <i>Velvet tamarin</i>(Icheku) Local Chewing Sticks on <i>Streptococcus mutans</i>Isolated from Human Mouth

Globally dental diseases are mainly caused by Streptococcus mutans, it is one of the leading causative agents of dental caries worldwide, because of its resistance to conventional antibacterial agents, alternative therapies are used to control resistance of oral pathogens. This research was done to determine the antibacterial activities of Psidium guajava (guava) and Velvet tamarin (Icheku) chewing sticks on Streptococcus mutans isolated from the oral cavity. The study was conducted in Owerri Imo State Nigeria during November-December period. Phytochemical analysis of the plant extracts was done using appropriate techniques. The procedure used for antimicrobial susceptibility test was disk diffusion method. Serial dilutions of Psidium guajava (guava) and Velvet tamarind (Icheku) extracts were prepared, Muller-Hinton media was used to put together the extract of serial dilutions of Psidium guajava (guava) and Velvet tamarin (Icheku) and a microbiological procedure were used for visually determining the minimum inhibitory concentration as well as minimum bactericidal concentration. Phytochemical evaluation of the plants’ extracts revealed that it contains saponins, tannins, alkaloid, steriods, glycosides and phenol. The results obtained from the antibacterial susceptibility testing of the extracts against Streptococcus mutans showed that the zones of inhibition recorded ranged from 18 mm to 27 mm. Ethanol (Soxhlet) extract of Icheku twig showed no zone of inhibition on the isolated organism. The ethanol (soxhlet) extract of the individual Psidium guajava (guava) and Velvet tamarin (Icheku) has a better antibacterial effect when compared to their aqueous extracts and combined forms. Psidium guajava (Guava) and Velvet tamarin (Icheku) twigs are made up of composite that is active against S. mutans and can be used in oral hygiene. There is a need for further investigation on the plant extracts as the rural poor make use of it because it is cheap, readily available and the rich also use it once they are in the village mostly in Eastern Nigeria. Similarly chewing sticks has been reported to be practiced by 90 of rural population in Nigeria.

Engineering Antibacterial Activities and Biocompatibility of Hyperbranched Lysine-based Random Copolymers

Antimicrobial peptides(AMPs)have been considered as an alternative to small molecule antibiotics since they are difficult to develop antimicrobial resistance.Hyperbranched polylysine(HPL),an AMP mimics,has gained attention due to its broad-spectrum antibacterial activities,but it also suffers from high toxicity.Here we report a facile strategy to engineer the toxicity of HPL by copolymerizing lysine(K)with a hydrophobic amino acid,e.g.,alanine(A),tryptophan(W)or phenylalanine(F),to afford hyperbranched random copolymers.These copolymers have comparable antibacterial activities to HPL while their cytotoxicities and in vivo toxicities are lowered when the type and content of hydrophobic amino acid and the size of copolymers are optimized.The G.mellonella infection model demonstrates that the copolymers are effective against the S.aureus infection in vivo.The copolymers kill the bacteria through the disruption of cell membranes and the bacteria do not develop resistance to the copolymers.

New Antibacterial Dihydropyrones Induced by Co-Culture of Penicillium crustosum PRB-2 and Penicillium citrinum HDN11-186

Two new dihydropyrones,rhytismatones C(1)and D(2),and a known compound,penicillenol A1(3),were isolated from the co-culture broth of the deep-sea-derived fungus Penicillium crustosum PRB-2 and Suaeda salsa-derived endophytic fungus Peni-cillium citrinum HDN11-186.Their structures were elucidated through comprehensive analysis of nuclear magnetic resonance(NMR)spectra and mass spectra.The absolute configurations of new compounds were determined by calculating the electronic circular di-chroism(ECD)spectrum.UPLC-MS data showed that compounds 1–3 could only be detected in the media of co-culture,suggesting new biosynthetic pathways were activated in the co-cultured fungi.Compound 1 showed obvious antibacterial activities against Pro-teus sp.MMBC-1002 and Bacillus subtilis MMBC-1004 with minimum inhibitory concentration(MIC)both at 25μmolL^(-1).

Molecular Characterization and Antibacterial Activity of a G-Type Lysozyme in Yellow Drum(Nibea albiflora)

Lysozyme(EC3.2.1.17)plays an important role in the immune response;as a nonspecific immune factor,it can resist causative agents.Lysozyme can be divided into c-type and g-type in fish.In a previous study,through genome-wide association analysis,the g-type lysozyme gene,which is named NaLyg in yellow drum(Nibea albiflora),was found to be a key candidate gene for disease resistance in response to Vibrio harveyi infection.The cDNA of NaLyg was 1025 bp,including four exons and three introns,and its open reading frame(ORF)had a full-length of 582 bp,encoding 193 amino acids.NaLyg was found to be conserved during evolution through bioinformatic analyses.The NaLyg protein possessed a sugar binding domain and three catalytic sites,including Glu71,Asp84 and Asp101.Quantitative qRT-PCR results confirmed that NaLyg gene mRNA was visibly increased after V.harveyi infection.The NaLyg protein purified by prokaryotic expression killed some gram-negative bacterial pathogens by inducing cell wall destruction,including V.harveyi,Aeromonas hydrophila and Edwardsiella tarda.Moreover,the NaLyg protein killed two gram-positive bacteria,Bacillus subtilis and Staphylococcus aureus.Taken together,the experimental results suggested that the NaLyg protein of N.albiflora played an important role in fighting bacterial infections.

Preparation and antibacterial activities of metal complexes of norfloxacin

The metal complexes of norfloxacin were prepared, and their structures were characterized using spectroscopic techniques like IR, 1H NMR, UV, atomic absorption, and CHN analysis. The solubility, melting point, and conductance measurements were also performed. These studies suggested that norfloxacin formed complexes with the metals utilizing carbonyl oxygen atom of the ring and carboxylic group oxygen atom. The antibacterial activities of these metal complexes against 14 different Gram-positive and Gram-negative microorganisms were studied by the disk susceptibility method. It was observed that the complexes of norfloxacin with magnesium, calcium, cobalt, nickel, and copper showed improved activity compared with the stated drug.

Novel 18β-glycyrrhetinic acid amide derivatives show dual-acting capabilities for controlling plant bacterial diseases through ROS-mediated antibacterial efficiency and activating plant defense responses

Natural products have long been a crucial source of,or provided inspiration for new agrochemical discovery.Naturally occurring 18β-glycyrrhetinic acid shows broad-spectrum bioactivities and is a potential skeleton for novel drug discovery.To extend the utility of 18β-glycyrrhetinic acid for agricultural uses,a series of novel 18β-glycyrrhetinic acid amide derivatives were prepared and evaluated for their antibacterial potency.Notably,compound 5k showed good antibacterial activity in vitro against Xanthomonas oryzae pv.oryzae(Xoo,EC50=3.64 mg L–1),and excellent protective activity(54.68%)against Xoo in vivo.Compound 5k induced excessive production and accumulation of reactive oxygen species in the tested pathogens,resulting in damaging the bacterial cell envelope.More interestingly,compound 5k could increase the activities of plant defense enzymes including catalase,superoxide dismutase,peroxidase,and phenylalanine ammonia lyase.Taken together,these enjoyable results suggested that designed compounds derived from 18β-glycyrrhetinic acid showed potential for controlling intractable plant bacterial diseases by disturbing the balance of the phytopathogen’s redox system and activating the plant defense system.

Antibacterial activities of a novel Cu-bearing high-entropy alloy against multi-drug-resistant Acinetobacter baumannii and Staphylococcus aureus

Acinetobacter baumannii and methicillin-resistant Staphylococcus aureus(MRSA)are two prevalent pathogens and have developed high resistant to most antibiotics.Therefore,it is a pressing need to develop a new method to inhibit the spread of drug-resistant bacteria.Copper containing high-entropy alloy(HEA,Al0.4CoCr-CuFeNi)is a new kind of alloy material,which shows extensive antibacterial activity and mechanical properties in our previous research.This study further develops another HEA(CoCrCuFeNi)and evaluates its resistance against gram-negative A.baumannii and Gram-positive MRSA.The antibacterial tests show that the antibacterial rate of the HEA toward both bacteria reached nearly 99%,far better than the traditional copper-bearing 304 stainless steel(304 Cu-SS).The biofilm observation shows that the HEA could not only kill the planktonic bacteria,but also effectively inhibit the formation of biofilm.These data demonstrate that CoCrCuFeNi HEA possesses effective antibacterial and antibiofilm activities,making it a potential candidate for using in hospital,food industry,and domestic kitchens.

Antibacterial and antiparasitic activities analysis of a hepcidinlike antimicrobial peptide from Larimichthys crocea

As an economically important marine fish,the large yellow croaker Larimichthys crocea suffered from marine white spot disease caused by the ectoparasite Cryptocaryon irritans in recent years.This disease not only could result in physiological damage,but also lead to secondary bacterial invasion.Reports indicated some AMPs(antimicrobial peptides)were of antiparasitic activity to C.irritans.Hepcidin-like(Lc-HepL)was one of the significant differential expression genes excavated from the transcriptome following a challenge with C.irritans.In this study,we characterized this AMP’s bioactivity based on the levels of mRNA and protein.After challenged by C.irritans,qRT-PCR showed Lc-HepL was significantly upregulated in six tissues,including gill,muscle,liver,head kidney and spleen during theront infection,trophont falling off,and secondary bacterial invasion stages,which implicated a role Lc-HepL played in the immune defense against C.irritans and secondary bacterial infection.Recombinant Lc-HepL(rLc-HepL)was induced and purified successfully.rLc-HepL exhibited antibacterial activity to certain bacteria in a dose-and time-dependent manners.Anti-C.irritans activity was explored for the first time and found it could cause the theronts membrane rupture and contents leakage.These results provided the first evidence that Lc-HepL had strong antiparasitic activity against marine fish ectoparasites C.irritans theronts.Together,data indicated that Lc-HepL might be an important component in the innate immune system against C.irritans and has the potential to be employed in future drug development.

In vitro degradation,photo-dynamic and thermal antibacterial activities of Cu-bearing chlorophyllin-induced Ca-P coating on magnesium alloy AZ31

Surgical failures,caused by postoperative infections of bone implants,are commonly met,which cannot be treated precisely with intravenous antibiotics.Photothermal therapy(PTT)and photodynamic therapy(PDT)have attracted widespread attention due to their non-invasive antibacterial effects on tissues and no bacterial resistance,which may be an excellent approach to solve infections related to bone implants for biodegradable magnesium alloys.Herein,a sodium copper chlorophyllin(SCC)with a porphyrin ring induced Ca-P coating was prepared on AZ31 magnesium alloy via layer-by-layer(LbL)assembly.The morphology and composition of the samples were characterized through field emission scanning electron microscope(FE-SEM)with affiliated energy dispersive spectrometer(EDS),X-ray diffractometer(XRD),and Fourier infrared spectrometer(FTIR)and X-ray photoelectron spectrometer(XPS)as well.Potentiodynamic polarization,electrochemical impedance spectroscopy(EIS)and hydrogen evolution experiments were employed to evaluate the corrosion behavior of the samples.Atomic absorption spectrophotometer was used to measure Cu elemental content of different immersion periods.Cytocompatibility and antibacterial performance of the coatings were probed using in vitro cytotoxicity tests(MTT assay),live/dead cell staining and plate counting method.The results showed that the obtained(Ca-P/SCC)10 coating exhibited good corrosion resistance,antimicrobial activity(especially under 808 nm irradiation)and biocompatibility.The antibacterial rates for E.coli and S.aureus were 99.9%and 99.8%,respectively;and the photothermal conversion efficiency was as high as 42.1%.Triple antibacterial mechanisms including photodynamic,photothermal reactions and copper-ions release were proposed.This coating exhibited a promising application for biodegradable magnesium alloys.