High-Density Dual-Structure Single-Atom Pt Electrocatalyst for Efficient Hydrogen Evolution and Multimodal Sensing.

Herein, we report a high-density dual-structure single-atom catalyst (SAC) by creating a large number of vacancies of O and Ti in two-dimensional (2D) Ti3C2 to immobilize Pt atoms (SA Pt-Ti3C2). The SA Pt-Ti3C2 showed excellent performance toward the pH-universal electrochemical hydrogen evolution reaction (HER) and multimodal sensing. For HER catalysis, compared to the commercial 20 wt % Pt/C, the Pt mass activities of SA Pt-Ti3C2 at the overpotentials of ∼30 and 110 mV in acid and alkaline media are 45 and 34 times higher, respectively. More importantly, during the alkaline HER process, an interesting synergetic effect between Pt-C and Pt-Ti sites that dominated the Volmer and Heyrovsky steps, respectively, was revealed. Moreover, the SA Pt-Ti3C2 catalyst exhibited high sensitivity (0.62-2.65 µA µM-1) and fast response properties for the multimodal identifications of ascorbic acid, dopamine, uric acid, and nitric oxide under the assistance of machine learning.

Organometallic Compound Stabilizes All-Inorganic Tin-Based Perovskite Nanocrystals Against Antisolvent Post-Treatment.

The isolation and purification of all-inorganic Sn-based perovskite nanocrystals (PNCs) remain troublesome, as common antisolvents accelerate the collapse of the optically active perovskite structure. Here, we mitigate such instabilities and endow strong resistance to antisolvent by incorporating the organometallic compound zinc diethyldithiocarbamate, Zn(DDTC)2, during the solution-based synthesis of all-inorganic CsSnI3 nanocrystals. Thiourea is shown to form through the thermal-driven conversion of Zn(DDTC)2 during synthesis, which binds to un-passivated Sn sites on the crystal surface and shields it from irreversible oxidation reactions. The CsSnI3 PNCs capped with thiourea show great stability after two purification cycles using methyl acetate, with negligible change in morphology, phase, and optical properties. Moreover, the modified PNCs are resistant to other commonly used antisolvents, like ethyl acetate, 1-pentanol, and isopropanol, offering a platform to explore all-inorganic Sn-based nanocrystalline thin films and optoelectronics.

Cronobacter sakazakii lysozyme inhibitor LprI mediated by HmsP and c-di-GMP is essential for biofilm formation and virulence.

Cronobacter sakazakii poses a significant threat, particularly to neonates and infants. Despite its strong pathogenicity, understanding of C. sakazakii biofilms and their role in infections remains limited. This study investigates the roles of HmsP and c-di-GMP in biofilm formation and identifies key genetic and proteomic elements involved. Gene knockout experiments reveal that HmsP and c-di-GMP are linked to biofilm formation in C. sakazakii. Comparative proteomic profiling identifies the lysozyme inhibitor protein LprI, which is downregulated in hmsP knockouts and upregulated in c-di-GMP knockouts, as a potential biofilm formation factor. Further investigation of the lprI knockout strain shows significantly reduced biofilm formation and decreased virulence in a rat infection model. Additionally, LprI is demonstrated to bind extracellular DNA, suggesting a role in anchoring C. sakazakii within the biofilm matrix. These findings enhance our understanding of the molecular mechanisms underlying biofilm formation and virulence in C. sakazakii, offering potential targets for therapeutic intervention and food production settings.IMPORTANCECronobacter sakazakii is a bacterium that poses a severe threat to neonates and infants. This research elucidates the role of the lysozyme inhibitor LprI, modulated by HmsP and c-di-GMP, and uncovers a key factor in biofilm formation and virulence. The findings offer crucial insights into the molecular interactions that enable C. sakazakii to form resilient biofilms and persist in hostile environments, such as those found in food production facilities. These insights not only enhance our understanding of C. sakazakii pathogenesis but also identify potential targets for novel therapeutic interventions to prevent or mitigate infections. This work is particularly relevant to public health and the food industry, where controlling C. sakazakii contamination in powdered infant formula is vital for safeguarding vulnerable populations.

Cascaded partitioned phase modulation for cross-connection of orbital angular momentum mode and polarization multiplexing channels.

Multi-dimensional orbital angular momentum (OAM) mode multiplexing provides a promising route for enlarging communication capacity and establishing comprehensive networks. While multi-dimensional multiplexing has gained advancements, the cross-connection of these multiplexed channels, especially involving modes and polarizations, remains challenging due to the needs for multi-mode interconversion and on-demand polarization control. Herein, we propose an OAM mode-polarization cross-transformation solution via cascaded partitioned phase modulation, which enables the divergently separated OAM modes to be independently phase-imposed within distinct spatial regions, leading to the synergistic conversion operation of mode and polarization channels. In demonstrations, we implemented the cross-connection of three OAM modes and two polarization multiplexed channels, achieving the mode purity that exceeds 0.951 and polarization contrast up to 0.947. The measured mode insertion losses and polarization conversion losses are below 3.42 and 3.54 dB, respectively. Consequently, 1.2 Tbit/s quadrature phase shift keying signals were successfully exchanged, yielding the bit-error-rates close to 10-6. Incorporating with increased partitioned phase treatments, this approach shows promise in accommodating massive mode-polarization multiplexed channels, which hold the potential to augment networking capability of large-scale OAM mode multiplexing communication networks.

Revealing the heterogeneous catalytic kinetics of PtRu nanocatalysts at the single particle level.

Comparison of the structural features and catalytic performance of bimetallic nanocatalysts will help to develop a unified understanding of structure-reaction relationships. The single-molecule fluorescence technique was utilized to reveal the differences in catalytic kinetics among PtRu bimetallic nanocatalysts and Pt and Ru monometallic nanocatalysts at the single particle level. The results show that bimetallic nanocatalysts have higher apparent rate constants and desorption rate constants relative to monometallic nanocatalysts, which leads to their higher catalytic activity. At the single particle level, bimetallic nanocatalysts have a wider distribution of apparent rate constants, suggesting that bimetallic nanocatalysts have higher activity heterogeneity relative to monometallic nanocatalysts. By investigating the relationship between the reaction rate and the rate of dynamic activity fluctuations, it was found that spontaneous surface restructuring and reaction-induced surface restructuring of nanoparticles occurred. The surface of bimetallic nanoparticles restructured faster, which made the bimetallic nanocatalysts more active. These findings provide new insights into the design of highly active bimetallic nanocatalysts.

Wide-angle camouflage detectors by manipulating emissivity using a non-reciprocal metasurface array.

Camouflage detectors that can detect incoming radiation from any angle without being detected are extremely important in stealth, guided missile, and heat-seeking missile industries. In order to accomplish this, the absorption and emission processes must be manipulated simultaneously. However, Kirchhoff's fundamental law suggests that absorption and emission are always in the same direction α(θ) = ε(θ), i.e., absorption and emission are reciprocal. This means that the emission from the detector always points back to the source, for example towards a laser source in a guided missile. Thus, detector emission serves as a complementary measure to hide an object. Here, we present a novel camouflage detector that uses a nonreciprocal metasurface array to independently detect the direction of the incoming radiation as well as manipulate its emissivity response. This is accomplished by using a magneto-optical material called indium arsenide (InAs), which breaks Lorentz reciprocity and Kirchhoff's fundamental law such that α(θ) ≠ ε(θ). This design results in the following absorption and emission: α(θ) = ε(-θ). Nine metasurfaces were designed, optimized, and operated at different incident angles from +50° to -50° at a wavelength of 13 µm. Furthermore, by keeping all metasurfaces in a pixilated array form, one could make a device that works over the full ±50° range. Potentially, this array of nonreciprocal metasurfaces can be used to fabricate thermal emitters or solar-harvesting systems.

Evolution and advances in endovascular mechanical thrombectomy of cerebral venous sinus thrombosis.

Cerebral venous sinus thrombosis (CVST) is a rare type of stroke and standard treatment involves anticoagulation. However, for some special CVST patients who are ineligible for anticoagulation or refractory to conservative treatment, endovascular treatment (EVT) may be an effective option. Mechanical thrombectomy (MT) is a commonly used treatment. Compared with anticoagulation treatment alone, MT may result in additional procedure-related complications, however, many studies have shown that it has a high rate of vessel recanalization and lower incidence of related complications in arterial large vessel occlusion stroke. In addition, the applicability of MT in children, patients with deep cerebral thrombosis, and patients with bleeding before treatment has been reported. MT combined with intravascular thrombolysis (IVT) and other multimodal therapeutic strategies, also has a good curative effect, and further research is needed to compare and optimize different treatment strategies. Owing to the low incidence of CVST, randomized controlled clinical trials with a large sample size to explore the safety and effectiveness of MT are scarce. In addition, devices specifically designed for cerebral venous sinus and effective endovascular therapies are currently not well-established. This article summarizes different endovascular instruments and multimodal therapies for cerebral venous thrombosis. We also discuss the limitations, prospects, prognostic factors, and applications in special cases of interventional thrombectomy.

Multimorbidity, healthy lifestyle, and the risk of cognitive impairment in Chinese older adults: a longitudinal cohort study.

BACKGROUND: Evidence on the association between multimorbidity and cognitive impairment in Chinese older population is limited. In addition, whether a healthy lifestyle can protect cognitive function in multimorbid older population remains unknown. METHODS: A total of 6116 participants aged ≥ 65 years from the Chinese Longitudinal Healthy Longevity Survey were followed up repeatedly. The number of coexisting chronic diseases was used for assessing multimorbidity and cardiometabolic multimorbidity. Three lifestyle statuses (unhealthy, intermediate, and healthy) were defined based on a lifestyle score covering smoking, alcohol drinking, body mass index, outdoor activities, and dietary pattern. Cognitive impairment was defined as the Mini-Mental State Examination score < 24. A modified Poisson regression model with robust error variance was used to assess the associations between multimorbidity, healthy lifestyle, and cognitive impairment. RESULTS: During a median follow-up period of 5.8 years, 1621 incident cases of cognitive impairment were identified. The relative risk (RR) of cognitive impairment associated with heavy multimorbidity burden (≥ 3 conditions) was 1.39 (95% confidence interval: 1.22-1.59). This association declined with age, with RRs being 3.08 (1.78-5.31), 1.40 (1.04-1.87), and 1.19 (1.01-1.40) in subjects aged < 70 years, ≥ 70 and < 80 years, and ≥ 80 years, respectively (P for interaction = 0.001). Compared to unhealthy lifestyle, a healthy lifestyle was related to an approximately 40% reduced risk of cognitive impairment regardless of multimorbidity burden. Among the 5 lifestyle factors assessed, daily outdoor activities and a healthy dietary pattern showed convincing protective effects on cognitive function. CONCLUSIONS: The relationship between multimorbidity and cognitive impairment is age-dependent but remains significant in the population aged 80 years or older. A healthy lifestyle may protect cognitive function regardless of the multimorbidity burden. These findings highlight the importance of targeting individuals with heavy multimorbidity burden and promoting a heathy lifestyle to prevent cognitive impairment in Chinese older population.

Safety and Tolerability of Direct Ischemic Postconditioning Following Thrombectomy for Acute Ischemic Stroke.

BACKGROUND: Experimental studies have demonstrated the neuroprotection of ischemic postconditioning (IPostC) in acute ischemic stroke by attenuating ischemia-reperfusion injury. This study aimed to investigate the safety and tolerability of direct IPostC in both a dog model and patients with acute ischemic stroke treated with thrombectomy. METHODS: The study involved 2 parts. First, IPostC was induced by repeated balloon inflation and deflation in dogs, where a low-pressure balloon was navigated to the anterior spinal artery, and 4 cycles of 5-minute ischemia followed by 5-minute reperfusion were performed. Vascular injuries were assessed using angiography and vascular tissue specimens. Then, a 3+3 dose-escalation trial was conducted in patients with acute ischemic stroke following successful thrombectomy recanalization. Patients received direct IPostC with ischemia and reperfusion durations in progressive increments of 0, 1, 2, 3, 4, and 5 minutes ×4 cycles. Major adverse responses were defined as vessel perforation, rupture, dissection, reocclusion, severe vasospasm, thrombotic events, and rupture of the balloon. RESULTS: IPostC was investigated in 4 dogs. No vessel perforation or rupture, dissection, or vasospasm was observed under the angiography. Only 1 vessel experienced mild injury between the intima and the internal elastic membrane detected on a histopathologic slide. Then, 18 patients were recruited. The duration of IPostC was progressively escalated with no major response happened. No patient experienced agitation, discomfort, or other tolerability issues. Five patients (27.8%) experienced any intracranial hemorrhage after thrombectomy, and 1 (5.6%) was symptomatic. At 3-month follow-up, no patient died, and 9 patients (50%) achieved functional independence. CONCLUSIONS: Direct IPostC inducing by 4 cycles of 5-minute ischemia followed by 5-minute reperfusion is safe, feasible, and tolerable in patients with acute ischemic stroke treated with thrombectomy. Further investigations are needed to determine the safety and preliminary efficacy of direct IPostC. REGISTRATION: URL: https://www. CLINICALTRIALS: gov; Unique identifier: NCT05153655.

Long Non-Coding RNA LPP-AS2 Plays an Anti-Tumor Role in Thyroid Carcinoma by Regulating the miR-132-3p/OLFM1 Axis.

The cancer-promoting function of the long non-coding RNA (lncRNA) LPP-AS2 has been documented in different cancers. Nonetheless, its role in thyroid carcinoma (THCA) remains unestablished. Reverse transcription quantitative polymerase chain reaction and Western blotting were conducted to estimate the expressions of lncRNA LPP-AS2, miR-132-3p, and OLFM1. The THCA cells' functions were assessed through CCK8 assays, Transwell invasion assays, scratch wound-healing migration assays, and quantification of caspase-3 activity. The in vivo assays were also implemented to assess tumor growth. Luciferase reporter and RNA immuno-precipitation assay (RIPA) experiments were executed to elucidate the interactions of miR-132-3p with lncRNA LPP-AS2 and OLFM1. THCA tissues and cells exhibited poor lncRNA LPP-AS2 and OLFM1 expressions and a robust expression of miR-132-3p. Overexpressing lncRNA LPP-AS2 constrained THCA cell proliferation, migration, and invasion and improved caspase-3 activity. The anti-tumor function of lncRNA LPP-AS2 was also validated in vivo. miR-132-3p had an interplay with lncRNA LPP-AS2 and OLFM1. Functionally, overexpressing miR-132-3p promoted the malignant THCA cell phenotypes. However, that tumor promotion was abolished by the additional overexpression of lncRNA LPP-AS2. The in vitro experiments also demonstrated that the repressive effect of OLFM1 overexpression on THCA cell malignant action could be offset by the miR-132-3p mimic. lncRNA LPP-AS2 impedes THCA progression via the miR-132-3p/OLFM1 axis. Our findings contribute a potential strategy in interfering with THCA progression.

A Plasmonic Fluor-Lightened Microneedle Array Enables Ultrasensitive Multitarget Whole Blood Diagnosis of Anemia in A Paper Origami-Based Device.

This work reports a portable, origami-type paper device with a plasmonic fluor-labeled microneedle sensing module for the multiplexed quantification of anemia biomarkers in whole blood. Sequential steps, including serum separation, target enrichment, and multiplexed readout by a gel imager, are rapidly accomplished with the flexible and highly integrated device. The microneedle array enabled efficient sampling of trace targets from ng mL-1 to pg mL-1 level. Combined with the plasmonic fluor label, the signal is improved by ≈7.6 folds compared with the flat substrate-based assay. The device is applied to simultaneously quantify hemoglobin (Hb), ferritin, folic acid (FA), and vitamin B12 (VB12 ), which are four anemia biomarkers distributed in different environments with different concentration ranges. Featured by the small sample volume (150 µL), short assay time (20 min), low cost (2 $), robust stability, and user-friendliness, the device is promising for the rapid and accurate diagnosis of anemia in real practice.

hsa_circ_0000285 facilitates thyroid cancer progression by regulating miR-127-5p/CDH2.

Thyroid cancer (THCA) is a leading endocrine cancer and becomes the fifth most commonly diagnosed malignancy in females. It is confirmed that circular RNAs (circRNAs) perform regulatory potencies in the pathological progress of THCA. Our purpose was to certify the trait of hsa_circ_0000285 (circ_0000285) and investigate its modulatory mechanism in THCA progression. We identified the expression profile of hsa_circ_0000285 in THCA by conducting qRT-PCR assay. Therewith, the potential of hsa_circ_0000285 in THCA development was determined with a set of functional experiments, including CCK-8, wound healing assay, Western blot, and xenograft model. The molecular mechanism underlying hsa_circ_0000285 was investigated with bioinformatic analysis, RIP and dual-luciferase reporter experiments. As opposed to normal samples and cells, hsa_circ_0000285 level was overtly increased in THCA specimens and cells. The downregulation of hsa_circ_0000285 weakened the proliferative and migratory capacity of THCA cells and promoted cell apoptosis. In addition, hsa_circ_0000285 silence suppressed the tumor growth of xenograft model mice in vivo. Notably, we demonstrated that hsa_circ_0000285 might target miR-127-5p/CDH2 axis in THCA. Afterward, our findings manifested that miR-127-5p attenuation blocked the function of hsa_circ_0000285 depletion in THCA cells. In the final step, CDH2 was proven to mediate the repressive potency of miR-127-5p in the malignant behaviors of THCA. Mechanistically, hsa_circ_0000285 induced the development of THCA via functioning as a competing endogenous RNA (ceRNA) of miR-127-5p to enhance CDH2 expression, which provided a new perspective for THCA therapy.

Plasmonic Photoelectrocatalysis in Copper-Platinum Core-Shell Nanoparticle Lattices.

This paper reports that strongly coupled bimetallic core-shell nanoparticle arrays show photoelectrocatalytic activity for hydrogen evolution reactions (HER). We fabricated large-area Cu-Pt nanoparticle lattices by combining top-down lithography and solution-based chemistry. These coupled lattices support two different types of plasmon modes, localized surface plasmons from individual particles and surface lattice resonances (SLRs) from the 2D lattice, that increased HER catalytic activity under white-light illumination up to 60%. Comparing photoelectrocatalytic performances of the two plasmon modes at different wavelength ranges, we found that SLRs had two-fold activity enhancement over that from localized surface plasmons.

Integrating Rh Species with NiFe-Layered Double Hydroxide for Overall Water Splitting.

NiFe-layered double hydroxide (LDH) is thought of as a promising bifunctional water-splitting catalyst, owing to its excellent performances for alkaline oxygen evolution reactions (OERs). However, it shows extremely poor activity toward hydrogen evolution reactions (HERs) due to the weak hydrogen adsorption. We demonstrated that the integration of Rh species and NiFe-LDH can dramatically improve its HER kinetics without sacrificing the OER performance. The Rh species were initially integrated into NiFe-LDH as oxidized dopants and metallic clusters (< 1 nm). In 1 M KOH electrolyte, an overpotential of 58 mV is needed to catalyze 10 mA cm-2 HER current density. Furthermore, this catalyst only requires 1.46 V to drive an electrolyzer at 10 mA cm-2. A strong interaction between metallic Rh clusters and NiFe hydroxide during the HER process is revealed. The theoretical calculation shows the Rh ions replace Fe ions as the major active sites that are responsible for OERs.

Current risk factors for HIV infection among blood donors in seven Chinese regions.

BACKGROUND: In China, there is a rising concern on the increasing trends of HIV infections in high-risk groups, who make blood donations that might potentially challenge the blood safety. Analyses on current risk factors for HIV infection among Chinese blood donors are urgently needed for developing effective strategies to defer high-risk donors and to warrant the safety of the blood supply. STUDY DESIGN AND METHODS: We recruited 313 HIV-positive and 762 HIV-negative donors from seven study sites in China and evaluated donor demographic characteristics, current medical and behavioral risk factors associated with HIV infection in a case-control survey. Univariable analyses examined the relationship between HIV infection and donor and donation characteristics, medical and behavioral risks, living conditions, and lifestyles. Multivariable logistic regression analyses evaluated the association between selected individual risks and HIV infection. Regression tree analysis was used to select covariates correlated with both HIV infection and individual risks and thus need to be controlled for in logistic regression models. RESULTS: Being a man who has sex with men was associated with the highest odds of HIV infection. Not using a condom, having sex with HIV-infected individuals, having sex partners with sexually transmitted diseases (STDs), having more than two concurrent sex partners, or having an STD were all associated with more than five times higher odds of having HIV. Having remunerated sex was associated with a 2.4 increased odds of having HIV infection. CONCLUSION: High-risk sexual behaviors were among the major risks for HIV infection among Chinese blood donors.

Metal-organic framework derived Co3Se4@Nitrogen-doped porous carbon as a high-performance anode material for lithium ion batteries.

In this paper, Co3Se4 nanoparticles embedded in nitrogen-doped porous carbon polyhedra are synthesized via a facile one-step thermal selenization, using zeolitic imidazolate framework-67 (ZIF-67) as the template. The electrochemical properties of the fabricated nanocomposite are evaluated for use as anodes for lithium ion batteries and found to exhibit a specific capacity (950 mAh g-1 at 0.2 C) and excellent cyclic stability (899 mAh g-1 at 1 C after 1000 cycles). Both are much higher than those of the state-of-the-art Co-Se based nanocomposites. This extraordinary lithium storage is attributed to the synergetic effect between the Co3Se4 nanocrystals and nitrogen-doped porous carbon framework, and is believed to offer a potential candidate anode material for next-generation lithium ion batteries.

Fluoride-Induced Dynamic Surface Self-Reconstruction Produces Unexpectedly Efficient Oxygen-Evolution Catalyst.

The oxygen-evolution reaction (OER) is a key process in water-splitting systems, fuel cells, and metal-air batteries, but the development of highly active and robust OER catalyst by simple methods is a great challenge. Here, we report an in situ dynamic surface self-reconstruction that can dramatically improve the catalytic activity of electrocatalysts. A fluoride (F-)-incorporating NiFe hydroxide (NiFe-OH-F) nanosheet array was initially grown on Ni foam by a one-step hydrothermal method, which requires a 243 mV over-potential (η) to achieve a 10 mA cm-2 current density with a Tafel slope of 42.9 mV dec-1 in alkaline media. After the surface self-reconstruction induced by fluoride leaching under OER conditions, the surface of NiFe-OH-F was converted into highly mesoporous and amorphous NiFe oxide hierarchical structure, and the OER activity at Î· = 220 mV increases over 58-fold. The corresponding η at 10 mA cm-2 decreases to 176 mV with an extreme low Tafel slope of 22.6 mV dec-1; this performance is superior to that of the state-of-the-art OER electrocatalysts.

FMO1 gene expression independently predicts favorable recurrence-free survival of classical papillary thyroid cancer.

Aim: To examine the expression profile of FMO1 in papillary thyroid cancer (PTC) and its prognostic value in recurrence-free survival (RFS). Methods: A retrospective analysis was performed using data from the Cancer Genome Atlas and Human Protein Atlas. Results: The most frequent variants of PTC had decreased FMO1 expression compared with their respective adjacent normal tissues. However, even under the best cut-off model, high FMO1 expression was only significantly associated with better RFS in classical PTC (p < 0.001), but not in other two variants. High FMO1 expression independently predicted favorable RFS (hazard ratio: 0.202; 95% CI: 0.084-0.487; p < 0.001) in classical PTC. Conclusion: High FMO1 expression might serve as a biomarker that independently predicts favorable RFS in classical PTC patients.

Phase Transformation of GeO2 Glass to Nanocrystals under Ambient Conditions.

Theoretically, the accomplishment of phase transformation requires sufficient energy to overcome the barriers of structure rearrangements. The transition of an amorphous structure to a crystalline structure is implemented traditionally by heating at high temperatures. However, phase transformation under ambient condition without involving external energy has not been reported. Here, we demonstrate that the phase transformation of GeO2 glass to nanocrystals can be triggered at ambient conditions when subjected to aqueous environments. In this case, continuous chemical reactions between amorphous GeO2 and water are responsible for the amorphous-to-crystalline transition. The dynamic evolution process is monitored by using in situ liquid-cell transmission electron microscopy, clearly revealing this phase transformation. It is the hydrolysis of amorphous GeO2 that leads to the formation of clusters with a size of ∼0.4 nm, followed by the development of dense liquid clusters, which subsequently aggregate to facilitate the nucleation and growth of GeO2 nanocrystals. Our finding breaks the traditional understanding of phase transformation and will bring about a significant revolution and contribution to the classical glass-crystallization theories.

The Electrochemical Response of Single Crystalline Copper Nanowires to Atmospheric Air and Aqueous Solution.

In this paper, single crystalline copper nanowires (CuNWs) have been electrochemically grown through anodic aluminum oxide template. The environmental stability of the as-obtained CuNWs in both 40% relative humidity (RH) atmosphere and 0.1 m NaOH aqueous solution has been subsequently studied. In 40% RH atmosphere, a uniform compact Cu2 O layer is formed as a function of exposure time following the logarithmic law and epitaxially covers the CuNW surfaces. It is also found that the oxide layers on CuNWs are sequentially grown when subjected to the cyclic voltammetry measurement in 0.1 m NaOH solution. An epitaxially homogeneous Cu2 O layer is initially formed over the surface of the CuNW substrates by solid-state reaction (SSR). Subsequently, the conversion of Cu2 O into epitaxial CuO based on the SSR takes place with the increase of applied potential. This CuO layer is partially dissolved in the solution forming Cu(OH)2 , which then redeposited on the CuNW surfaces (i.e., dissolution-redeposition (DR) process) giving rise to a mixed polycrystalline CuO/Cu(OH)2 layer. The further increase of applied potential allows the complete oxidation of Cu2 O into CuO to form a dual-layer structure (i.e., CuO inner layer and Cu(OH)2 outer layer) with random orientations through an enhanced DR process.