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Superlattices-a periodic stacking of two-dimensional layers of two or more materials-provide a versatile scheme for engineering materials with tailored properties1,2. Here we report an intrinsic heterodimensional superlattice consisting of alternating layers of two-dimensional vanadium disulfide (VS2) and a one-dimensional vanadium sulfide (VS) chain array, deposited directly by chemical vapour deposition. This unique superlattice features an unconventional 1T stacking with a monoclinic unit cell of VS2/VS layers identified by scanning transmission electron microscopy. An unexpected Hall effect, persisting up to 380 kelvin, is observed when the magnetic field is in-plane, a condition under which the Hall effect usually vanishes. The observation of this effect is supported by theoretical calculations, and can be attributed to an unconventional anomalous Hall effect owing to an out-of-plane Berry curvature induced by an in-plane magnetic field, which is related to the one-dimensional VS chain. Our work expands the conventional understanding of superlattices and will stimulate the synthesis of more extraordinary superstructures.
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Diketopiperazine alkaloids have proven the most abundant heterocyclic alkaloids up to now, which usually process diverse scaffolds and rich biological activities. In our search for bioactive diketopiperazine alkaloids from marine-derived fungi, two novel diketopiperazine alkaloids, penipiperazine A (1) and its biogenetically related new metabolite (2), together with a known analogue neofipiperzine C (3), were obtained from the strain Penicillium brasilianum. Their planar structures and absolute configurations were elucidated by extensive spectroscopic analyses, 13C NMR calculation, Marfey's, ECD, and ORD methods. Compound 1 featured a unique 6/5/6/6/5 indole-pyrazino-pyrazino-pyrrolo system, and its plausible biogenetic pathway was also proposed. Additionally, compounds 1-3 have been tested for their inflammatory activities. 1 and 2 significantly inhibited the release of NO and the expression of related pro-inflammatory cytokines on LPS-stimulated RAW264.7 cells, suggesting they could be attracting candidate for further development as anti-inflammatory agent. KEY POINTS: ⢠A novel diketopiperazine alkaloid featuring a unique 6/5/6/6/5 indole-pyrazino-pyrazino-pyrrolo system was isolated from the marine fungus Penicillium brasilianum. ⢠The structure of 1 was elucidated by detailed analysis of 2D NMR data, 13C NMR calculation, Marfey's, ECD, and ORD methods. ⢠Compounds 1 and 2 significantly inhibited the release of NO and the expression of related pro-inflammatory cytokines on LPS-stimulated RAW264.7 cells.
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Alcaloides , Penicillium , Dicetopiperazinas/farmacologia , Lipopolissacarídeos , Fungos , Alcaloides/química , Indóis , Anti-Inflamatórios/farmacologia , Citocinas , Estrutura Molecular , Alcaloides Indólicos/farmacologia , Alcaloides Indólicos/químicaRESUMO
There are many kinds of agricultural pathogenic fungi, which may belong to pathogenic fungi in different species, such as Fusarium, Alternaria, Colletotrichum, Phytophthora, and other agricultural pathogens. Pathogenic fungi from different sources are widely distributed in agriculture, which threaten the lives of crops around the world and caused great damage to agricultural production and economic benefits. Due to the particularity of the marine environment, marine-derived fungi could produce natural compounds with unique structures, rich diversities, and significant bioactivities. Since marine natural products with different structural characteristics could inhibit different kinds of agricultural pathogenic fungi, secondary metabolites with antifungal activity could be used as lead compounds against agricultural pathogenic fungi. In order to summarize the structural characteristics of marine natural products against agricultural pathogenic fungi, this review systematically overview the activities against agricultural pathogenic fungi of 198 secondary metabolites from different marine fungal sources. A total of 92 references published from 1998 to 2022 were cited. KEY POINTS: ⢠Pathogenic fungi, which could cause damage to agriculture, were classified. ⢠Structurally diverse antifungal compounds from marine-derived fungi were summarized. ⢠The sources and distributions of these bioactive metabolites were analyzed.
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Produtos Biológicos , Fusarium , Antifúngicos/farmacologia , Antifúngicos/metabolismo , Produtos Biológicos/metabolismo , Fungos/metabolismo , Alternaria/metabolismo , Fusarium/metabolismoRESUMO
Aquatic pathogens, including Vibrio, Edwardsiella, Pseudomonas, and Aeromonas, which could result in bacterial diseases to aquaculture, have seriously threatened the world aquaculture production. Marine-derived fungi, which could produce novel secondary metabolites with significant antibacterial activity, may be an important source for finding effective agents against aquatic pathogens. In this review, a systematically overview of the harm of several aquatic pathogens, and 134 antibacterial secondary metabolites against aquatic pathogens from 13 genera of marine-derived fungi, were summarized and concluded. The aim of this review is to find out the relationships between activity and structural type, between bioactive compounds and their hosts, and so on. Altogether, 95 references published during 1997-2021 were cited. KEY POINTS: â¢Aquatic pathogens, which could result in bacterial diseases to aquaculture, were described. â¢Marine fungal metabolites with activities against aquatic pathogens were summarized. â¢The distributions of these bioactive marine fungal metabolites were analyzed.
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Antibacterianos , Organismos Aquáticos , Antibacterianos/metabolismo , Aquicultura , Organismos Aquáticos/metabolismoRESUMO
Three new polyketides, eutyketides A and B (1 and 2) and cytosporin X (3), along with four known compounds (4-7), were obtained from the marine-derived fungus Eutypella scoparia. The planar structures of 1 and 2 were elucidated by extensive HRMS and 1D and 2D NMR analyses. Their relative configurations of C-13 and C-14 were determined with chemical conversions by introducing an acetonylidene group. The absolute configurations of 1-3 were determined by comparing their experimental electronic circular dichroism (ECD) data with their computed ECD results. All of the isolated compounds were tested for their anti-inflammatory activities on lipopolysaccharide-induced nitric oxide production in RAW 264.7 macrophages. Compounds 5 and 6 showed stronger anti-inflammatory activities than the other compounds, with the inhibition of 49.0% and 54.9% at a concentration of 50.0 µg/mL, respectively.
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Ascomicetos , Policetídeos , Anti-Inflamatórios/farmacologia , Ascomicetos/química , Estrutura Molecular , Policetídeos/químicaRESUMO
Pressure-induced non-molecular phases of polymeric nitrogen have potential applications in the field of energetic materials. Here, through a structural search method combined with first-principles calculations, we have predicted four novel nitrogen-rich aluminum nitrides C2/m-AlN6, Cm-Al2N7, C2-Al2N7 and P1-AlN7. Nitrogen atoms polymerize into infinite chains in C2/m-AlN6, C2-Al2N7 and P1-AlN7 structures and form N3 chains and N4 rings in Cm-Al2N7. C2/m-AlN6 is stable in the pressure range from 30 to 80 GPa and Cm-Al2N7, C2-Al2N7 and P1-AlN7 are metastable in the pressure ranges of 35-65, 65-80 and 41-80 GPa, respectively. The present study predicts that C2/m-AlN6 has a superconducting transition temperature of 18.9 K at 0 GPa and can be quenched and recovered under ambient conditions. The energy densities of C2/m-AlN6, Cm-Al2N7, C2-Al2N7 and P1-AlN7 compounds are expected to be 4.80, 4.59, 5.46 and 5.59 kJ g-1, respectively, due to their high nitrogen content, indicating that they have potential to be high-energy density materials. The calculated Vickers hardness of C2/m-AlN6, Cm-Al2N7, Cm-Al2N7 and P1-AlN7 is 43.86, 39.32, 63.96 and 33.58 GPa, respectively, showing that the novel nitrogen-rich aluminum nitrides are potential superhard materials as well. This study may encourage further experimental exploration of high N content superhard or high-energy density nitrides.
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A new method for the rapid determination of the metabolites oxalate and citrate in urine samples was based on capillary electrophoresis and capacitively coupled contactless conductivity detection coupled with solid-phase extraction. The detection cell for capacitively coupled contactless conductivity detection was improved with a smaller inner volume (1.5 nL), reduced noise (0.2â¼0.5 mV) and better reproducibility and durability. Under optimal conditions, oxalate and citrate can achieve baseline separation within 4 min and the detection limits (S/N = 3) for oxalate and citrate are about 44 and 244 ng/mL, respectively. The overall recovery is between 80.0 and 89.2%. This method offers a better choice for quantitative analysis of strong anions such as oxalate and citrate in diagnostic testing associated with human diseases.
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Ácido Cítrico/isolamento & purificação , Ácido Cítrico/urina , Eletroforese Capilar/métodos , Oxalatos/isolamento & purificação , Oxalatos/urina , Extração em Fase Sólida/métodos , Condutividade Elétrica , Eletroforese Capilar/instrumentação , Humanos , Limite de DetecçãoRESUMO
Two new kinds of alanine-substituted calix[4]arene stationary phases of 5,11,17,23-p-tert-butyl-25,27-bis(l-alanine-methylester-N-carbonyl-methoxy)-26,28-dihyroxycalix[4]arene-bonded silica gel stationary phase (BABS4) and 5, 11, 17, 23-p-tert-butyl-25,26,27,28-tetra(l-alanine-methylester-N-carbonyl-methoxy)-calix[4]arene-bonded silica gel stationary phase (TABS4) were prepared and characterized in the present study. They were compared with each other and investigated in terms of their chromatographic performance by using polycyclic aromatic hydrocarbons, disubstituted benzene isomers, and mono-substituted benzenes as solute probes. The results indicated that both BABS4 and TABS4 exhibited multiple interactions with analytes. In addition, the commonly used Tanaka characterization protocol for the evaluation of commercially available stationary phases was applied to evaluate the properties of these two new functionalized calixarene stationary phases. The Tanaka test results were compared with Zorbax Eclipse XDB C18 and Kromasil phenyl columns, respectively. BABS4 has stronger hydrogen-bonding capacity and ion-exchange capacity than TABS4, and features weaker hydrophobicity and hydrophobic selectivity. Both of them behave similarly in stereoselectivity. Both BABS4 and TABS4 are weaker than C18 and phenyl stationary phases in hydrophobicity and hydrophobic selectivity.
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A low-protein diet (LPD) has become an important way to delay the progression of chronic kidney disease (CKD) and to delay the need for dialysis. A review of the literature reveals the low-protein diet's influence on the course of chronic kidney disease. An artificial low-protein food, wheat starch, for example, can not only increase the high-quality protein intake ratio, but can ensure adequate energy intake on a low-protein diet while meeting the nutritional needs of the body, effectively reducing the burden on the damaged kidneys. The purpose of this review is to provide a reference for the clinical implementation of diet and nutrition therapy in patients with chronic kidney disease.
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Dieta com Restrição de Proteínas , Progressão da Doença , Insuficiência Renal Crônica , Humanos , Dieta com Restrição de Proteínas/métodos , Insuficiência Renal Crônica/dietoterapia , Insuficiência Renal Crônica/terapia , Proteínas Alimentares/administração & dosagemRESUMO
The administration of drugs resident to counteract fluid washout has received considerable attention. However, the fabrication of a biocompatible system with adequate adhesion and tissue penetration capability remains challenging. This study presents a cell membrane-inspired carrier at the subcellular scale that facilitates interfacial adhesion and tissue penetration to improve drug delivery efficiency. Both chitosan oligosaccharide (COS) and oleic acid (OA) modified membranes exhibit a high affinity for interacting with the negatively charged glycosaminoglycan layer, demonstrating that the zeta potential of the carrier is the key to determining spontaneous penetration and accumulation within the bladder tissue. In vivo modeling has shown that a high surface charge significantly improves the retention of the drug carrier in the presence of urine washout. Possibly due to charge distribution, electric field gradients, and lipid membrane softening, the high positive surface charge enabled the carriers to penetrate the urinary bladder barrier and/or enter the cell interior. Overall, this study represents a practical and effective delivery strategy for tissue binders.
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Quitosana , Lipossomos , Sistemas de Liberação de Medicamentos , Portadores de FármacosRESUMO
Small-diameter tissue-engineered vascular grafts (sdTEVGs) have garnered significant attention as a potential treatment modality for vascular bypass grafting and replacement therapy. However, the intimal hyperplasia and thrombosis are two major complications that impair graft patency during transplantation. To address this issue, we fabricated the covalent-organic framework (COF)-based carbon monoxide (CO) nanogenerator-and co-immobilized with LXW-7 peptide and heparin to establish a multifunctional surface on TEVGs constructed from acellular blood vessels for preventing thrombosis and stenosis. The cell-adhesive peptide LXW-7 could capture endothelial-forming cells (EFCs) to promote endothelialization, while the antithrombotic molecule heparin prevented thrombus formation. The reactive oxygen species (ROS)-triggered CO release suppressed the adhesion and activation of macrophages, leading to the reduction of ROS and inflammatory factors. As a result, the endothelial-to-mesenchymal transition (EndMT) triggered by inflammation was restricted, facilitating the maintenance of the homeostasis of the neo-endothelium and preventing pathological remodeling in TEVGs. When transplanted in vivo, these vascular grafts exhibited negligible intimal hyperplasia and remained patent for 3 months. This achievement provided a novel approach for constructing antithrombotic and anti-hyperplastic TEVGs.
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OBJECTIVE: To develop the method of gas chromatography-mass spectrometry (GC-MS) for simultaneous determination of 15 herbicides in blood. METHODS: 2ml of blood in vitro were sampled, concentrated and extracted with dichloromethane, reconstant with methanol agents of Gulonic acid lactone solution, and detected by GC-MS. RESULTS: Experimental results show that diazinon, atrazine, prometryn, methyl parathion, butachlor, bifenthrin at 4-80 microg/L, phorate, malathion, 2,4-D butyl ester, chlordane, fenpropathrin at 10-200 microg/L, alpha-endosulfan, beta-endosulfan, cyhalothrin at 20-400 microg/L, dimethoate at 40-800 microg/L, with good linear response. The correlation coefficient (r2) were between 0.998-1.000, respectively. The recovery of all analysts averaged between 56%-128% in blood samples. The detection limits of all compounds between 0.05 and 1.00 microg/L. The lower limit of quantification between 0.20 and 3.001 microg/L. CONCLUSION: The methods is apply to detect the content of analysts in blood samples.
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Cromatografia Gasosa-Espectrometria de Massas/métodos , Resíduos de Praguicidas/sangue , Atrazina/sangue , Diazinon/sangue , Humanos , Prometrina/sangueRESUMO
OBJECTIVE: Efficacy and safety of five common surgical treatments for lower calyceal (LC) stones were assessed for LC stones 20 mm or less. METHODS: A systematic literature search was conducted up to June 2020 using PubMed, EMBASE, and Cochrane Library. The study has been registered in PROSPERO, CRD42021228404. Randomized controlled trials evaluating the efficacy and safety of five common surgical treatments for LC stones were collected, including percutaneous nephrolithotomy (PCNL), mini-PCNL (MPCNL), ultramini-PCNL (UMPCNL), extracorporeal shock wave lithotripsy (ESWL), and retrograde intrarenal surgery (RIRS). Heterogeneity among studies was assessed by using global inconsistency and local inconsistency. Both pooled odds ratio, along with 95% credible interval (CI) and the surface under the cumulative ranking curve values were calculated to assess the outcomes, paired comparisons of efficacy and safety of five treatments. RESULTS: Nine peer-reviewed randomized controlled trials, comprising 1674 patients in recent 10 years, were included. Heterogeneity tests showed no statistical significance, and a consistency model was chosen, respectively. The order of surface under the cumulative ranking curve values for efficacy was as follows: PCNL (79.4), MPCNL (75.2), UMPCNL (66.3), RIRS (29), and eSWL (0). For safety: eSWL (84.2), UMPCNL (82.2), RIRS (52.9), MPCNL (16.6), and PCNL (14.1). CONCLUSION: In the current study, all five treatments are both effective and safe. Many factors must be considered to choose surgical treatments for LC stones 20 mm or less; the results that we separate conventional PCNL into PCNL, MPCNL, and UMPCNL make the questions even more controversial. However, relative judgments are still needed to be used as reference data in clinical management. For efficacy, PCNL>MPCNL>UMPCNL>RIRS>ESWL, ESWL is statistically inferior to the other four treatments, respectively. RIRS is statistically inferior to PCNL and MPCNL, respectively. For safety, ESWL>UMPCNL>RIRS>MPCNL>PCNL, ESWL is statistically superior to RIRS, MPCNL, and PCNL, respectively. RIRS is statistically superior to PCNL. We cannot reach conclusions about which surgical treatment is the best choice for all patients with LC stones 20 mm or less; therefore, tailored treatments based on individual patients still demand more attention than ever before for both patients and urologists.
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Cálculos Renais , Litotripsia , Nefrolitotomia Percutânea , Nefrostomia Percutânea , Humanos , Metanálise em Rede , Cálculos Renais/cirurgia , Nefrolitotomia Percutânea/métodos , Razão de Chances , Resultado do Tratamento , Nefrostomia Percutânea/efeitos adversosRESUMO
OBJECTIVE: The efficacy and safety of minimally invasive nephrolithotomy (MPCNL) versus retrograde intrarenal surgery (RIRS) was assessed for lower calyceal (LC) stones. METHODS: Our team conducted a systematic literature search up to December, 2022, using PUBMED, EMBASE and the Cochrane Library. The study was registered in PROSPERO, CRD 42021247197. Randomized controlled trials evaluating the efficacy and safety of MPCNL versus RIRS for LC stones were collected. Heterogeneity among the studies was assessed using the χ 2 test based on the Q and I2 tests. Pooled effect sizes were calculated using a fixed model if I2 is less than 50%; otherwise, a random-effects model was chosen. The primary outcomes were the 3-month stone-free rate (3SFR) and total complications, while the secondary outcomes were the operating time, hospital stay, haemoglobin reduction, bleeding, postoperative fever and complications with the Clavien-Dindo system. A subgroup analysis of 10-20 mm LC stones was also designed. RESULTS: A total of 7 peer-reviewed trials comprising 711 patients were identified. No statistical differences were observed in the heterogeneity results of the 3SFR or total complications ( P >0.1, I2 < 50%). Compared with RIRS, MPCNL had an unfavourable safety profile, resulting in total complications [odds ratio (OR): 1.87 (95% CI: 1.05, 3.33); P =0.03], haemoglobin reduction [OR: 0.81 (95% CI: 0.15, 1.47); P =0.02] and complications with Grade I [OR: 5.52 (95% CI: 1.34, 22.83); P =0.02] but an improved efficacy and 3SFR [OR: 2.43 (95% CI: 1.48, 3.97); P =0.0004]. As for the 10-20 mm LC stones, compared with RIRS, MPCNL also had an unfavourable safety profile, resulting in total complications [OR: 2.47 (95% CI: 1.20, 5.07); P =0.01], complications with Grade I [OR: 4.97 (95% CI: 0.99, 25.01); P =0.05] and an increased hospital stay [OR: 2.46 (95% CI: 2.26, 2.66); P =0.00001] but an improved efficacy and 3SFR {OR: 3.10 (95% CI: 1.61, 5.99); P =0.0008]. The efficacy effect of MPCNL and safety effect of RIRS were nearly equal for both stones sized less than 20 mm (number needed to treat = 17, number needed to harm = 20) and stones sized 10-20 mm (number needed to treat = 20, number needed to harm = 13). No statistical difference was found between the MPCNL and RIRS groups for the rest of outcomes. CONCLUSION: Both MPCNL and RIRS are safe and effective management methods. Moreover, compared with RIRS, MPCNL had an unfavourable safety profile but improved efficacy for LC stones of ≤20 mm or 10-20 mm, and the differences were statistically significant. The relative profit of efficacy of MPCNL was similar to the relative profit of safety of RIRS.
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Cálculos Renais , Nefrostomia Percutânea , Humanos , Cálculos Renais/cirurgia , Nefrotomia , Tempo de Internação , Hemoglobinas , Resultado do Tratamento , Nefrostomia Percutânea/métodosRESUMO
A new withanolide, talasteroid (1), and a known steroid (2), along with eight meroterpenoids (3-10), were obtained from the rice culture of the marine-derived fungus Talaromyces stollii HBU-115. The structure of 1 including its absolute configuration was determined by extensive 1 D and 2 D NMR spectroscopy, and single-crystal X-ray diffraction analysis. Compound 1 represents the first withanolide featuring a 4-substituted 2,3-dimethyl-2-butenolide ring in the side chain. The isolated compounds were evaluated for their antimicrobial and antioxidant activities.
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Diabetic cystopathy (DCP) is one of the most common and troublesome urologic complications of diabetes mellitus, characterized by chronic low-grade inflammatory response. However, the correlation between inflammation and disease progression remains ambiguous and effective drugs interventions remain deficient. Herein, during 12-week study, 48 male Sprague-Dawley rats were randomly assigned to four groups: negative control (NC), NC treated with aspirin (NC+Aspirin), DCP, and DCP treated with aspirin (DCP+Aspirin). Type 1 diabetes mellitus was established by intraperitoneal injection of streptozotocin (65 mg/kg). After 2 weeks modeling, the rats in treatment groups received daily oral aspirin (100 mg/kg/d). After 10 weeks of treatment, aspirin ameliorated pathological weight loss and bladder weight increase in diabetic rats, accompanied by a 16.5% decrease in blood glucose concentrations. H&E, Masson, immunohistochemistry and transmission electron microscopy revealed that a dilated bladder with thickened detrusor smooth muscle (DSM) layer, inflammatory infiltration, fibrosis and ultrastructural damage were observed in diabetic rats, which were obviously ameliorated by aspirin. The dynamic investigations at 4, 7 and 10 weeks revealed inflammation gradually increased as the disease progresses. After 10 weeks of treatment, the expression of TNF-α, IL-1ß, IL-6, and NF-κB has been decreased to 78%, 39.7%, 44.1%, 33.3% at mRNA level and 67.6%, 76.7%, 71.4%, 67.1% at protein level, respectively (DCP+Aspirin vs. DCP, p < 0.01). Aspirin partially restored the increased expression of inflammatory mediators in bladder DSM of diabetic rats. The study provided insight into long-term medication therapies, indicating that aspirin might serve as a potential strategy for DCP treatment.
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Diabetes Mellitus Experimental , Diabetes Mellitus Tipo 1 , Masculino , Animais , Ratos , Ratos Sprague-Dawley , Aspirina/farmacologia , Aspirina/uso terapêutico , Diabetes Mellitus Experimental/complicações , Diabetes Mellitus Experimental/tratamento farmacológico , Inflamação/tratamento farmacológicoRESUMO
Ligand-mediated interface control has been broadly applied as a powerful tool in constructing asymmetric multicomponent nanoparticles (AMNP), and induces the anisotropic growth with fine-tuning morphology, composition, plasmonic property and functionality. As a new kind of AMNP, the synthesis of Janus Au-Ag nanoparticles with tunable negative surface curvature is still a challenge. Here, we demonstrate that the synergistic surface energy effects between gold nanodumbbells (Au NDs) with a negative surface curvature and 4-mercaptobenzoic acid (4-MBA) can direct the site-selective growth of anisotropic silver domains on gold nanodumbbells (Au NDs@Ag NPs). By adjusting the 4-MBA concentration-dependent interfacial energy, the Au NDs@Ag NPs could be continuously tuned from dumbbell-like core-shell structures, to L-shaped Janus, and then rod-like core-shell structures with directional and asymmetric spatial distributions of resizable Ag domains by site-selective growth. Based on the calculation results of discrete dipole approximation (DDA) method, it has been found that the Au NDs@Ag L-shaped Janus NPs with Ag island domains created polarization orientation-dependent plasmonic extinction spectra and hot spots around the negatively curved waist and Ag domains. The L-shaped Janus Au NDs@Ag NPs exhibited significantly plasmonic spectrum properties with four apparent LSPR peaks that cover from visible to near-infrared range and higher surface-enhanced Raman scattering (SERS) activity compared with the original Au NDs. The best SERS enhancement factor of 1.41 × 107 was achieved. This synergistic surface energy effect-based method involving the asymmetric growth of silver coating on gold nanoparticles with negatively curved surface presents a new method to design and fabricate nanometer optical devices based on asymmetric multicomponent nanoparticles.
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Electrical stimulation is an effective strategy for facilitating wound healing. However, it is hindered by unwieldy electrical systems. In this study, a light-powered dressing based on long-lived photoacid generator (PAG)-doped polyaniline composites is used, which can generate a photocurrent under visible light irradiation to interact with the endogenous electric field and facilitate skin growth. Light-controlled proton binding and dissociation result in oxidation and reduction of the polyaniline backbone, inducing charge transfer to generate a photocurrent. Due to the rapid intramolecular photoreaction of PAG, a long-lived proton-induced localized acidic environment is formed, which protects the wound from microbial infection. In summary, a simple and effective therapeutic strategy is introduced for light-powered and biocompatible wound dressings that show great potential for wound treatment.
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Prótons , Cicatrização , Compostos de Anilina , BandagensRESUMO
Nitrogen-rich compounds containing polynitrogen are attractive candidates for high-energy-density materials. In this work, using first-principles calculations and a particle swarm optimization structural search method, four novel nitrogen-rich structures are predicted at high pressures, i.e., two ZnN3phases with the same space groupP1 (low-pressure phase LP-ZnN3and high-pressure phase HP-ZnN3),Cmm2-ZnN5andPcc2-ZnN6, the energy density are estimated to be 1.41 kJ g-1, 1.88 kJ g-1, 4.07 kJ g-1, and 2.60 kJ g-1, respectively. LP-ZnN3(54-72 GPa) and HP-ZnN3(above 72 GPa) have the lowest enthalpies in all known ZnN3phases, and the N6chains in LP-ZnN3polymerize into infinite nitrogen chains in HP-ZnN3at 72 GPa, showing a narrow-band-gap-semiconductor to metallic phase transition. Interestingly,P1-ZnN3has a superconducting transition temperature of 6.2 K at 50 GPa and 16.3 K at 100 GPa. InCmm2-ZnN5andPcc2-ZnN6, nitrogen atoms polymerize into three-dimensional network structures and network layers under high pressures. Those predicted structures may enrich the phase diagram of high-pressure zinc nitrides, and provide clues for synthesis and exploration of novel stable polymeric nitrogen.