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1.
Front Oncol ; 11: 733369, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34616681

RESUMO

Steroidal alkaloids contain both steroidal and alkaloid properties in terms of chemical properties and pharmacological activities. Due to outstanding biological activities such as alkaloids and similar pharmacological effects to other steroids, steroidal alkaloids have received special attention in anticancer activity recently. Substituted groups in chemical structure play markedly important roles in biological activities. Therefore, the effective way to obtain lead compounds quickly is structural modification, which is guided by structure-activity relationships (SARs). This review presents the SAR of steroidal alkaloids and anticancer, including pregnane alkaloids, cyclopregnane alkaloids, cholestane alkaloids, C-nor-D-homosteroidal alkaloids, and bis-steroidal pyrazine. A summary of SAR can powerfully help to design and synthesize more lead compounds.

2.
Chemistry ; 2021 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-34599532

RESUMO

The assembly of two tripyridinium-tricarboxylate ligands and different metal ions leads to seven isostructural MOFs, which show novel 2D®2D supramolecular entanglement featuring catenane-like interlocking of tricyclic cages. The MOFs show tripyridinium-afforded and metal-modulated photoresponsive properties. The MOFs with d 10 metal centers ( 1-Cd, 1-Zn, 2-Cd, 2-Zn) show fast and reversible photochromism and concomitant fluorescence quenching, 1-Ni displays slower photochromism but does not fluoresce, and 1-Co and 2-Co are neither photochromic nor fluorescent. We show that the network entanglement dictates donor-acceptor close contacts, which enable fluorescence originated from interligand charge transfer. The contacts also allow photoinduced electron transfer, which underlies photochromism and concomitant fluorescence response. The metal dependence in fluorescence and photochromism can be related to energy transfer through metal-centered d-d transitions. In addition, 1-Cd is demonstrated to be a potential fluorescence sensor for sensitive and selective detection of UO 2 2+ in water.

3.
Bioresour Technol ; 341: 125906, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34523564

RESUMO

This study aims to explore the impacts of the Fenton-like reaction on hydrogen peroxide, hydroxyl radicals, humic substance (HS) formation, laccase activity and microbial communities during composting to optimize composting performances. The results indicated that the activity of laccase in the presence of the Fenton-like reaction (HC) (35.92 U/g) was significantly higher than that in the control (CP) (29.56 U/g). The content of HS in HC (151.91 g/kg) was higher than that in CP (131.73 g/kg), and amides, quinones, aliphatic compounds and aromatic compounds were promoted to form HS in HC by 2D-FTIR-COS analysis. Proteobacteria contributed most greatly to AA1 at phylum level, Pseudomonas and Sphingomonas abundances increased in HC. Redundancy analysis indicated that there was a strong positive correlation among the Fenton-like reaction, laccase and HS. Conclusively, the Fenton-like reaction improved the activity of laccase, promoted the formation of HS and enhanced the quality of compost.


Assuntos
Compostagem , Substâncias Húmicas/análise , Lacase , Esterco , Solo
4.
Int J Mol Sci ; 22(18)2021 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-34576206

RESUMO

Actinobacillus pleuropneumoniae is a pathogen that infects pigs and poses a serious threat to the pig industry. The emergence of quinolone-resistant strains of A.pleuropneumoniae further limits the choice of treatment. However, the mechanisms behind quinolone resistance in A.pleuropneumoniae remain unclear. The genomes of a ciprofloxacin-resistant strain, A. pleuropneumoniae SC1810 and its isogenic drug-sensitive counterpart were sequenced and analyzed using various bioinformatics tools, revealing 559 differentially expressed genes. The biological membrane, plasmid-mediated quinolone resistance genes and quinolone resistance-determining region were detected. Upregulated expression of efflux pump genes led to ciprofloxacin resistance. The expression of two porins, OmpP2B and LamB, was significantly downregulated in the mutant. Three nonsynonymous mutations in the mutant strain disrupted the water-metal ion bridge, subsequently reducing the affinity of the quinolone-enzyme complex for metal ions and leading to cross-resistance to multiple quinolones. The mechanism of quinolone resistance in A. pleuropneumoniae may involve inhibition of expression of the outer membrane protein genes ompP2B and lamB to decrease drug influx, overexpression of AcrB in the efflux pump to enhance its drug-pumping ability, and mutation in the quinolone resistance-determining region to weaken the binding of the remaining drugs. These findings will provide new potential targets for treatment.

5.
Micron ; 150: 103144, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34534922

RESUMO

As a potential novel superalloy, the study on the creep of high entropy alloys is of great significance. Equiatomic ratio CoCrFeMnNi with a mass of 6.7 kg was fabricated by vacuum induction levitation melting. Dendrite structure is obtained for as-cast alloy while a homogeneous equiaxed grain structure can be formed after annealing at 1273 K for 6 h. The tensile creep behavior of as-annealed alloy at 773-973 K and 50-340 MPa is systematically studied. Apparent dynamic recovery and recrystallization occur for creep at 973 K while high dislocation density can be observed for creep at 923 K and lower temperatures. Results of EDS analyses on fractured surface, stress exponent and activation energy for steady state creep rate suggest that the creep mechanism should be the dislocation viscous glide dragged by solute Mn at low stresses and low temperatures and be the dislocation climb associated with Mn diffusion at high stresses and high temperatures.

6.
Chemosphere ; 287(Pt 3): 132338, 2021 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-34563774

RESUMO

Manure fertilization contributes to crop production and sustainable agriculture by introducing large amounts of nutrients and exogenous microbes into soil. However, the contribution of exogenous microbes in shaping soil bacterial community and network structure after fertilization are still controversial. In this study, bacterial communities and network structure that received unsterilized (R + C) or sterilized (R + SC) manure fertilizers, as well as no fertilizer control (R), were characterized using high throughput sequencing. Results showed that the relative abundance of fertilizer-derived OTUs decreased from 10.4% to 4.6% after 90 days incubation, while the Bray-Curtis distance between the control and fertilization group (R + C and R + SC) gradually increased with the culture time. It can be supposed that manure fertilization altered soil bacterial communities by interfering the growth of indigenous bacteria rather than the colonization of fertilizer-derived bacteria. Network analysis showed that a subset of the fertilizer-derived OTUs identified as Xanthomonadales order and Promicromonospora, Constrictibacter genera acted as connectors between modules. They enhanced the interactions not only between soil-derived OTUs and fertilizer-derived OTUs, but also within indigenous bacteria, supported that the introduction of fertilizer-derived exogenous bacteria contributes large to soil bacterial network association. Moreover, fertilizer-derived OTUs presented to be positively correlated with soil pH, while majority soil-derived OTUs presented to be negatively correlated with various physicochemical variables (pH, DOC, NO3-, and LAP). Our study highlighted the critical role of fertilizer-derived bacteria in regulating indigenous soil microbial community and network formation after fertilization.

7.
Front Cardiovasc Med ; 8: 712524, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34527712

RESUMO

Objectives: To evaluate the effects of thoracic endovascular aortic repair (TEVAR) in descending aorta for retrograde type A aortic intramural hematoma (re-TAIMH). Methods: From January 2013 to September 2019, 65 consecutive patients diagnosed with re-TAIMH and treated by TEVAR were enrolled in this retrospective cohort study, of whom 44 patients presented with entry tear in descending aorta (Group A) and 21 with penetrating atherosclerotic ulcer (Group B). The clinical data, including baseline characteristics, adverse events, aortic remolding, and overall survival were reviewed. Results: The mean age of all the patients was 52.0 ± 8.3 years, and 54 (83.1%) patients were men. The mean maximal ascending aortic diameter (MAAD) was 43.1 ± 5.4 mm, and the mean maximal ascending aortic hematoma thickness (MAAHT) was 9.6 ± 4.7 mm. TEVAR was performed under general anesthesia in 53 (81.5%) patients, while 12 (18.5%) patients were treated under local anesthesia. There were two deaths during hospitalization (one with rupture and another with multiple organ dysfunction syndrome), and overall survival at 1, 4, and 7 years for all 65 patients was 93.8, 92.0, and 87.4%, respectively. The MAAD and MAATH decreased significantly after TEVAR (p < 0.05) in the two groups, so did the mean descending aortic diameter at the pulmonary bifurcation level. Type I endoleak, dialysis, progression to type A aortic dissection, and enlargement in MAAHT and MAAD were more common complications, which occurred in four, three, two, and two patients, respectively. Conclusion: Patients with retrograde TAIMH treated by TEVAR had a favorable prognosis including late survival and aortic remolding. However, some post-intervention complications were not negligible.

8.
J Microbiol Methods ; 190: 106339, 2021 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-34592373

RESUMO

Lower respiratory tract infections (LRTIs) are a leading cause of morbidity and mortality worldwide and lack a rapid diagnostic method. To improve the diagnosis of LRTIs, we established an available loop-mediated isothermal amplification (LAMP) assay for the detection of eight common lower respiratory pathogens, including Klebsiella pneumoniae, Pseudomonas aeruginosa, Acinetobacter baumannii, Staphylococcus aureus, Escherichia coli, Haemophilus influenzae, Streptococcus pneumoniae, and Moraxella catarrhalis. The whole process can be achieved within 1 h (sample to results read out). We established an extraction free isothermal system. 528 sputum samples collected from patients suspected to have LRTIs were analyzed by the system (8 tests in each sample, a total of 4224 tests) and compared with the standard culture method (SCM). The samples with inconsistent results were further verified by Sanger sequencing and High-throughput sequencing (NGS). The detection limits of the LAMP assay for the 8 pathogens ranged from 103 to 104 CFU/mL. Upon testing 528 samples, the Kappa coefficients of all pathogens ranged between 0.5 and 0.7 indicated a moderate agreement between the LAMP assay and the SCM. All inconsistent samples were further verified by Sanger sequencing, we found that the developed LAMP assay had a higher consistency level with Sanger sequencing than the SCM for all pathogens. Additionally, when the NGS was set to a diagnostic gold standard, the specificity and sensitivity of the LAMP assay for LRTIs were 94.49% and 75.00%. The present study demonstrated that the developed LAMP has high consistency with the sequencing methods. Meanwhile, the LAMP assay has a higher detection rate compared to the SCM. It may be a powerful tool for rapid and reliable clinical diagnosis of LRTIs in primary hospitals.

9.
Front Pharmacol ; 12: 720307, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34483932

RESUMO

Glioblastoma multiforme (GBM) is one of the most malignant primary tumors in humans. Despite standard therapeutic strategy with tumor resection combined with radiochemotherapy, the prognosis remains disappointed. Recently, deubiquitinating enzymes (DUBs) has been reported as potential cancer therapy targets due to their multifunctions involved in the regulation of tumorigenesis, cell cycle, apoptosis, and autophagy. In this study, we found that knockdown of ubiquitin specific protease (USP5), a family member of DUB, could significantly suppress GBM cell line U251 and DBTRG-05MG proliferation and colony formation by inducing cell cycle G1/S arrest, which was correlated with downregulation of CyclinD1 protein level. CyclinD1 had been reported to play a critical role in the tumorigenesis and development of GBM via regulating cell cycle transition. Overexpression of USP5 could significantly extend the half-life of CyclinD1, while knockdown of USP5 decreased the protein level of CyclinD1, which could be restored by proteasome inhibitor MG-132. Indeed, USP5 was found to directly interact with CyclinD1, and decrease its K48-linked polyubiquitination level. Furthermore, knockdown of USP5 in U251 cells remarkably inhibited tumor growth in vivo. Taken together, these findings demonstrate that USP5 plays a critical role in tumorigenesis and progression of GBM by stabilizing CyclinD1 protein. Targeting USP5 could be a potential therapeutic strategy for GBM.

10.
Adv Mater ; : e2105049, 2021 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-34510587

RESUMO

Breaking the bottleneck of hydrogen oxidation/evolution reactions (HOR/HER) in alkaline media is of tremendous importance for the development of anion exchange membrane fuel cells/water electrolyzers. Atomically dispersed active sites are known to exhibit excellent activity and selectivity toward diverse catalytic reactions. Here, a class of unique Rh2 Sb nanocrystals with multiple nanobranches (denoted as Rh2 Sb NBs) and atomically dispersed Rh sites are reported as promising electrocatalysts for alkaline HOR/HER. Rh2 Sb NBs/C exhibits superior HER performance with a low overpotential and a small Tafel slope, outperforming both Rh NBs/C and commercial Pt/C. Significantly, Rh2 Sb NBs show outstanding HOR performance of which the HOR specific activity and mass activity are about 9.9 and 10.1 times to those of Rh NBs/C, and about 4.2 and 3.7 times to those of Pt/C, respectively. Strikingly, Rh2 Sb NBs can also exhibit excellent CO tolerance during HOR, whose activity can be largely maintained even at 100 ppm CO impurity. Density functional theory calculations reveal that the unsaturated Rh sites on Rh2 Sb NBs surface are crucial for the enhanced alkaline HER and HOR activities. This work provides a unique catalyst design for efficient hydrogen electrocatalysis, which is critical for the development of alkaline fuel cells and beyond.

11.
J Am Chem Soc ; 143(36): 14464-14469, 2021 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-34473484

RESUMO

An organophosphorus-catalyzed method for the synthesis of unsymmetrical hydrazines by cross-selective intermolecular N-N reductive coupling is reported. This method employs a small ring phosphacycle (phosphetane) catalyst together with hydrosilane as the terminal reductant to drive reductive coupling of nitroarenes and anilines with good chemoselectivity and functional group tolerance. Mechanistic investigations support an autotandem catalytic reaction cascade in which the organophosphorus catalyst drives two sequential and mechanistically distinct reduction events via PIII/PV═O cycling in order to furnish the target N-N bond.

12.
Anesthesiology ; 135(5): 930-931, 2021 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-34554194
13.
Langmuir ; 37(39): 11429-11446, 2021 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-34559540

RESUMO

The creeping-flow theory describing evolution and steady-state shape of two-dimensional ionic-conductor drops under the action of surface tension and the subcritical (in terms of the electric Bond number) electric field imposed in the substrate plane is developed. On the other hand, the experimental data are acquired for drops impacted or softly deposited on dielectric surfaces of different wettability and subjected to an in-plane subcritical electric field. Even though the experimental situation involves viscous friction of drops with the substrates and wettability-driven motion of the contact line, the comparison to the theory reveals that it can accurately describe the steady-state drop shape on a non-wettable substrate. In the latter case, the drop is sufficiently raised above the substrate, which diminishes the three-dimensional effects, making the two-dimensional description (lacking the no-slip condition at the substrate and wettability-driven motion of the contact line) relevant. Accordingly, it is demonstrated how the subcritical electric field deforms the initially circular drops until an elongated steady-state configuration is reached. In particular, the surface tension tends to round off the non-circular drops stretched by the electric Maxwell stresses imposed by the electrodes. A more pronounced substrate wettability leads to more elongated steady-state configurations observed experimentally than those predicted by the two-dimensional theory. The latter cases reveal significant three-dimensional effects in the electrically driven drop stretching. In the supercritical electric fields (corresponding to the supercritical electric Bond numbers), the electrical stretching of drops predicted by the present linearized two-dimensional theory results in splitting into two separate droplets. This scenario is corroborated by the predictions of the fully nonlinear results for similar electrically stretched bubbles in the creeping-flow regime available in the literature as well as by the present experimental results on a substrate with slip.

14.
Vet Res ; 52(1): 120, 2021 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-34526128

RESUMO

Gyrovirus 3 (GyV3), the third novel emerging species of the genus Gyrovirus of the Anelloviridae family, has been described in multiple hosts. Epidemiologically, there are suggestions that GyV3 is associated with diarrhea/proventriculitis, however, no direct causal evidence exists between GyV3 infection and specific clinical diseases. Herein, we infected special pathogen-free (SPF) chickens with GyV3, and then assessed the pathogenicity and tissue tropism. The results revealed that GyV3 induced persistent infection characterized by diarrhea, aplastic anemia, immunosuppression, and persistent systemic lymphocytic inflammation. Clinically, the infected chickens presented ruffled feathers, diarrhea, anemia, and weight loss. Aplastic anemia was characterized by progressive depletion of hematopoietic cells in the bone marrow, immunosuppression was associated with atrophy of the thymus, spleen, and bursa of Fabricious, progressive lymphocytic inflammations were characterized by proventriculitis, adrenalitis, pancreatitis, hepatitis, nephritis, and bronchitis. Viral loads of GyV3 in tissues exhibited "M", "N", "W" or "V" type dynamic changes. The highest level of viral loads was reported in bone marrow at 7dpi, followed by the adrenal gland at 2 dpi, the sciatic nerve at 7 dpi, and bile at 35 dpi. The bone marrow and kidney demonstrate the strongest immunostaining of GyV3-VP1 antigen and were suggested as the target tissues of GyV3. Collectively, GyV3 is an immunosuppressive pathogenic virus that targets the bone marrow and kidney in chickens. Exploring the pathogenicity and tissue tropism of GyV3 will guide the basic understanding of the biology of GyV3 and its pathogenesis in chickens.

15.
iScience ; 24(9): 102990, 2021 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-34485869

RESUMO

Utilizing high-pressure to modulate optical properties, such as thermoreflectance (dR/dT), over a wide range has received much attention. Nevertheless, how the pressure exerts on the complex dielectric constant and finally on dR/dT remains elusive. Here, we perform a thoroughly experimental and theoretical investigation on dR/dT of Al nano-film from 0 to 25 GPa. The dR/dT values exhibit a sine-like pressure-dependence, with the zero-crossing appearing at around 6 GPa. These special phenomena are well explained from electron transition viewpoints. The first-principles calculations show that the energy difference of parallel bands is enlarged from 1.45 to 2 eV, thereby increasing the threshold for electron transitions. The lifted threshold changes the optical absorption rates of Al and the density of states of the electrons involving interband transitions; finally, the resulting dR/dT exhibits such a pressure-dependent behavior. Our findings provide a deep insight on pressure-induced electronic transitions and photon-electron interactions in metals.

17.
Appl Environ Microbiol ; 87(20): e0133921, 2021 09 28.
Artigo em Inglês | MEDLINE | ID: mdl-34347514

RESUMO

Permafrost soils store approximately twice the amount of carbon currently present in Earth's atmosphere and are acutely impacted by climate change due to the polar amplification of increasing global temperature. Many organic-rich permafrost sediments are located on large river floodplains, where river channel migration periodically erodes and redeposits the upper tens of meters of sediment. Channel migration exerts a first-order control on the geographic distribution of permafrost and floodplain stratigraphy and thus may affect microbial habitats. To examine how river channel migration in discontinuous permafrost environments affects microbial community composition, we used amplicon sequencing of the 16S rRNA gene on sediment samples from floodplain cores and exposed riverbanks along the Koyukuk River, a large tributary of the Yukon River in west-central Alaska. Microbial communities are sensitive to permafrost thaw: communities found in deep samples thawed by the river closely resembled near-surface active-layer communities in nonmetric multidimensional scaling analyses but did not resemble floodplain permafrost communities at the same depth. Microbial communities also displayed lower diversity and evenness in permafrost than in both the active layer and permafrost-free point bars recently deposited by river channel migration. Taxonomic assignments based on 16S and quantitative PCR for the methyl coenzyme M reductase functional gene demonstrated that methanogens and methanotrophs are abundant in older permafrost-bearing deposits but not in younger, nonpermafrost point bar deposits. The results suggested that river migration, which regulates the distribution of permafrost, also modulates the distribution of microbes potentially capable of producing and consuming methane on the Koyukuk River floodplain. IMPORTANCE Arctic lowlands contain large quantities of soil organic carbon that is currently sequestered in permafrost. With rising temperatures, permafrost thaw may allow this carbon to be consumed by microbial communities and released to the atmosphere as carbon dioxide or methane. We used gene sequencing to determine the microbial communities present in the floodplain of a river running through discontinuous permafrost. We found that the river's lateral movement across its floodplain influences the occurrence of certain microbial communities-in particular, methane-cycling microbes were present on the older, permafrost-bearing eroding riverbank but absent on the newly deposited river bars. Riverbank sediment had microbial communities more similar to those of the floodplain active-layer samples than permafrost samples from the same depth. Therefore, spatial patterns of river migration influence the distribution of microbial taxa relevant to the warming Arctic climate.

18.
J Phys Chem B ; 125(34): 9860-9869, 2021 09 02.
Artigo em Inglês | MEDLINE | ID: mdl-34428041

RESUMO

Poly-NIPAm microgel particles with two different cross-linking densities were prepared with the classical batch polymerization process. These particles were adsorbed onto modified silica surfaces, and their nanomechanical properties were measured by means of atomic force microscopy. It was found that these particles have a hard core-soft shell structure both below and above the volume transition temperature. The core-shell-like structure appears due to a higher reaction rate of the cross-linker compared to that of the monomer, leading to depletion of cross-linker in the shell region. The microgel beads with lower average cross-linking density were found to be less stiff below the volume transition temperature than the microgel with higher cross-linking density. Increasing the temperature further to just above the volume transition temperature led to lower stiffness of the more highly cross-linked microgel compared to its less cross-linked counterpart. This effect is explained with the more gradual deswelling with temperature for the more cross-linked microgel particles. This phenomenon was confirmed by dynamic light scattering measurements in the bulk phase, which showed that the larger cross-linking density microgel showed a more gradual collapse in aqueous solution as the temperature was increased.


Assuntos
Microgéis , Resinas Acrílicas , Géis , Temperatura
19.
Curr Microbiol ; 78(10): 3686-3695, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34406433

RESUMO

Aflatoxin B1 (AFB1) contamination in feed and food seriously threatens the healthy growth of animals and humans, and it may lead to huge economic losses in livestock and poultry production. Therefore, screening of high-efficient AFB1-degrading bacteria is necessary to ensure the safety of feed and food. The study aims to isolate and characterize bacteria from various sources to explore its AFB1 degradation potential. Fifteen bacterial were obtained using a medium containing coumarin as the sole carbon source; only one strain showed a good-degrading ability in culture media by adding AFB1 and it was selected for further studies. A gram-negative and spore-forming, designated E1, was identified as Paenibacillus pabuli, with the highest sequence similarity to P. pabuli NBRC13638T (98.97%). The growth of the strain E1 was observed under 22-47 °C, pH 5.5-9.5 and NaCl concentration 0-6% (w/v), with optimum growth at 37 °C, pH 7.5 and 1% NaCl. The biodegradation characteristics of object strain were detected by high performance liquid chromatography (HPLC). The degradation ratio of AFB1 reached 55% at 24 h and 70.2% at 48 h. After 96 h, the degradation rate of AFB1 reached 85.9%. The active degradation components were present in the cell-free supernatant of strain E1, and the degradation ratio of AFB1 reached 80.0% after 96 h. It is the first report that genus Paenibacillus could degrade AFB1. Moreover, E1 has highly adaptable to diverse environmental conditions. It will be a potential candidate for biodegradation of mycotoxins in feed and food.


Assuntos
Aflatoxina B1 , Paenibacillus , Animais , Biodegradação Ambiental , Meios de Cultura , Humanos , Paenibacillus/genética
20.
Chem Asian J ; 2021 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-34431617

RESUMO

The construction of a heterogeneous nanocatalyst with outstanding catalytic performance via an environmentally benign and cost-effective synthetic category has long been one of the challenges in nanotechnology. Herein, we synthesized highly efficient and low-cost mesoporous morphology-dependent CuO/CeO2 -Rods and CuO/CeO2 -Cubes catalysts by employing a green and multifunctional polyphenolic compound (tannic acid) as the stabilizer and chelating agent for 4-nitrophenol (4-NP) reduction reaction. The CuO/CeO2 -Rods exhibited excellent performance, of which the activity was 3.2 times higher than that of CuO/CeO2 -Cubes. This can be connected with the higher density of oxygen vacancy on CeO2 -Rods (110) than CeO2 -Cubes (100), the oxygen vacancy favors anchoring CuO species on the CeO2 support, which promotes the strong interaction between finely dispersed CuO and CeO2 -Rods at the interfacial positions and facilitates the electron transfer from BH4 - to 4-NP. The synergistic catalytic mechanism illustrated that 4-NP molecules preferentially adsorbed on the CeO2 , while H2 from BH4 - dissociated over CuO to form highly active H* species, contributing to achieving efficient hydrogenation of 4-NP. This study is expected to shed light on designing and synthesizing cost-effective and high-performance nanocatalysts through a greener synthetic method for the areas of catalysis, nanomaterial science and engineering, and chemical synthesis.

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