Improved Electrical Resistivity of Atomic-Layer-Deposited Copper Thin Films on Polyimide Substrates by an In Situ ZnO Interlayer.

The low-temperature atomic layer deposition of metal on polymer surfaces is often challenging owing to the deficiency of functional groups and reactivity. Here, the deposition of ALD-Cu employing Cu(hfac)2 and Et2Zn at a low temperature (120 °C) on polyimide (PI) substrates is improved by the utilization of an in situ ultrathin ALD-ZnO buffer layer. A conformal and continuous ALD-Cu thin film with low resistivity (6.07 µΩ cm) is fabricated on an ALD-ZnO/PI substrate. The findings demonstrate that the ALD-ZnO buffer layer provides chemisorption and a nucleation site for the initial growth of ALD-Cu. Transmission electron microscopy and energy-dispersive X-ray analysis reveal that the ALD-ZnO layer plays a buffer role in the fitness of ALD-Cu on PI substrates and its ability to elicit the formation of an ALD-ZnO nanocluster and polar surface. ALD-ZnO can be effectively utilized as a buffer layer for polymer-based ALD-metal processes, showing potential in flexible electronic applications.

Predicting Lifetime and Reliability of Porous Platinum Electrodes in Solid-State Electrolyte Sensors: An Atomic Anharmonic Theory Approach.

Solid-state electrolyte sensors operate at high temperatures for extended periods of time, which can cause internal structural deformation and degradation of material properties due to issues such as mismatched coefficients of thermal expansion. Therefore, predicting and extending the lifetime of sensors are urgent and important issue. In this study, the relationship between the damping coefficient of electrode materials and the porosity and temperature was determined using atomic anharmonic theory. A lifetime model for the porous platinum electrode was established, and the effects of porosity and anharmonic atomic vibrations on the characteristic lifetime and reliability of porous platinum electrodes were investigated. The results show that the morphology parameters of the electrode material increase nonlinearly with increasing temperature but the change is very small. The characteristic lifetime decreases sharply at first and then tends to remain constant with increasing porosity. In the case of the simple harmonic approximation, neither the characteristic lifetime nor the reliability of the electrode material changes with temperature. However, considering the anharmonic atomic vibration, the characteristic lifetime and reliability of the electrode material are smaller than those of the simple harmonic approximation, and both of them decrease with increasing temperature. The higher the temperature, the greater the difference between the results of anharmonic and harmonic, and the more significant the anharmonic effect. The reliability decreases with an increasing porosity and time.

The Diagnostic Performance of Laboratory Tests of Neurosyphilis: A Systematic Review and Network Meta-Analysis.

INTRODUCTION: The gold standard for diagnosing neurosyphilis (NS) is currently unavailable; various laboratory parameters in cerebrospinal fluid (CSF) and blood can assist in the diagnosis. METHODS: PubMed, Embase, and the Cochrane Library were searched. Studies utilizing laboratory tests to assist in the diagnosis of NS were included. The pooled indicators for diagnostic performance and their respective 95% confidence intervals (CIs) were calculated. We used the superiority index to test the superiority of a diagnostic test. RESULTS: Eleven citations were included in the study. Albumin quotient, CSF-TPHA, CSF-EIA, CSF-LDH, CSF-WBC, CSF-CXCL13, FTA-ABS, CSF-PCR, RPR, CSF-TPPA, TRUST, and CSF-venereal diseases research laboratory (VDRL) were assessed in the studies included. The pooled estimates of sensitivity, specificity, AUC of SROC and their respective 95% CIs for CSF-TPPA and CSF-VDRL were 0.97 (0.17, 1.00), 0.84 (0.62, 0.95), 0.93 (0.91, 0.95) and 0.74 (0.59, 0.85), 0.99 (0.93, 1.00), 0.94 (0.91, 0.96), respectively. CSF-TPHA demonstrated the highest relative sensitivity. CSF-VDRL manifested the highest specificity. CSF-TPHA, TRUST, CSF-VDRL, CSF-EIA, and RPR ranked in the top five laboratory tests with superiority index. CONCLUSION: CSF-TPHA, TRUST, CSF-VDRL, CSF-EIA, and RPR indicate acceptable performance in detecting NS compared to other modalities. Comprehensive diagnostic strategies still play a significant role in the diagnosis of NS.

Theoretical Study on the Influence of the Anharmonic Effect on the Ionic Conductivity and Thermal Stability of 8 mol% Yttria-Stabilized Zirconia Solid Electrolyte Material.

YSZ is a promising material for resistive memory devices due to its high concentration of oxygen vacancies, which provide the high anion migration rates crucial for the manifestation of resistance switching in metal oxides. Therefore, investigating the ionic conductivity of YSZ is an important issue. The ionic conductivity and thermal stability of 8 mol% YSZ were studied using the theories and methods of solid-state physics and physical chemistry. The impact of anomalous atomic vibrations on the material was also explored, and the variation in the ion vibration frequency, electrical conductivity, and thermal stability coefficient of electrical conductivity with temperature was obtained. The results show that the ion conductivity of an 8 mol% YSZ solid electrolyte increases nonlinearly with temperature, with a smaller increase at lower temperatures and a larger increase at higher temperatures. Considering the anharmonic effect of ion vibrations, the electrolyte conductivity is higher than the result of the harmonic approximation, and the anharmonic effect becomes more significant at higher temperatures. Our research fills the gap in the current literature regarding the theoretical non-harmonic exploration of the ion conductivity and thermal stability factor of YSZ solid electrolytes. These results provide valuable theoretical guidance for the development and application of high-performance YSZ resistive memory devices in high-temperature environments.

Flexible but Refractory Single-Crystalline Hyperbolic Metamaterials.

The fabrication of flexible single-crystalline plasmonic or photonic components in a scalable way is fundamentally important to flexible electronic and photonic devices with high speed, high energy efficiency, and high reliability. However, it remains a challenge. Here, we have successfully synthesized flexible single-crystalline optical hyperbolic metamaterials by directly depositing refractory nitride superlattices on flexible fluorophlogopite-mica substrates with magnetron sputtering. Interestingly, these flexible hyperbolic metamaterials show dual-band hyperbolic dispersion of dielectric constants with small dielectric losses and high figures of merit in the visible to near-infrared ranges. More importantly, the optical properties of these nitride-based flexible hyperbolic metamaterials show remarkable stability during 1000 °C heating or after being bent 1000 times. Therefore, the strategy developed in this work offers an easy and scalable route for fabricating flexible, high-performance, and refractory plasmonic or photonic components, which can significantly expand the applications of current electronic and photonic devices.

Addressing the Conflict between Mobility and Stability in Oxide Thin-film Transistors.

Amorphous oxide semiconductor thin-film transistors (AOS TFTs) are ever-increasingly utilized in displays. However, to bring high mobility and excellent stability together is a daunting challenge. Here, the carrier transport/relaxation bilayer stacked AOS TFTs are investigated to solve the mobility-stability conflict. The charge transport layer (CTL) is made of amorphous In-rich InSnZnO, which favors big average effective coordination number for all cations and more edge-shared structures for better charge transport. Praseodymium-doped InSnZnO is used as the charge relaxation layer (CRL), which substantially shortens the photoelectron lifetime as revealed by femtosecond transient absorption spectroscopy. The CTL and CRL with the thickness suitable for industrial production respectively afford minute potential barrier fluctuation for charge transport and fast relaxation for photo-generated carriers, resulting in transistors with an ultrahigh mobility (75.5 cm2 V-1 s-1 ) and small negative-bias-illumination-stress/positive-bias-temperature-stress voltage shifts (-1.64/0.76 V). The design concept provides a promising route to address the mobility-stability conflict for high-end displays.

Neuropsychological Features in Patients with General Paresis of the Insane at an Early Stage.

BACKGROUND This study aimed to explore the features of cognitive impairment in patients with neurosyphilis at the early stage of mild cognitive impairment (MCI). MATERIAL AND METHODS A total of 18 patients with asymptomatic neurosyphilis (ANS), 19 patients with neurosyphilis at the MCI stage (neurosyphilis-MCI), and 15 patients with neurosyphilis at the dementia stage (neurosyphilis-dementia) were enrolled. Cognitive function was evaluated using comprehensive rating scales. Tests of syphilis in blood and cerebrospinal fluid (CSF) were conducted, and white blood cell (WBC) counts and protein levels in CSF were measured. RESULTS Overall cognitive function and individual cognitive domains, including memory, language, visuospatial skill, and attention/executive function, were all significantly impaired in the neurosyphilis-MCI group compared with the ANS group, and were further impaired in the neurosyphilis-dementia group. Although there was no difference in serum rapid plasma regain (RPR) titer among the 3 groups, the number of patients with serum RPR titer ≥1: 32 in the neurosyphilis-MCI group was much higher than that in the ANS group. CSF RPR positive rate in the neurosyphilis-MCI group was significantly higher than that in the ANS group. The WBC count, protein level, and the rate of elevated protein level or increased WBC count in CSF did not differ among the 3 groups. CONCLUSIONS The feature of cognitive impairment of neurosyphilis-MCI patients displayed multiple-domain amnestic MCI. Perhaps there were extensive brain areas involved at the early stage, and a continuous neuroinflammatory process was through the different stages of neurosyphilis. Early diagnosis and treatment are very important for preventing the progression of general paresis of the insane.

Ultrafast changes in effective permittivity of hyperbolic metamaterials and related multi-resonance-induced ultrafast process excited by femtosecond pulses.

Hyperbolic metamaterials (HMMs) exhibit rich optical nonlinear responses for the epsilon-near-zero (ENZ) and anisotropy. In this study, we extract the time-dependent change in the effective permittivity of an Ag nanorod array under femtosecond pulses pumping around its ENZ wavelength. The transmittance and transient absorption spectra measured by s- and p-polarizations are used in the extraction process. We experimentally confirm the existence of an ultrafast recovery process with a relaxation time of 0.24 ps in the transient absorption spectra. The calculation based on the extracted nonlinear effective permittivity indicates that the ultrafast signal originates from the superposition of two slower recovery processes, with relaxation times of 0.74 ps and 1.19 ps, respectively. The results indicate that when the responses of two nonlinear processes have different signs and recovery speeds, their superposition may cause faster signal recovery in the combined process than in the two individual processes.

Effect of Preparation Method on the Catalytic Performance of HZSM-5 Zeolite Catalysts in the MTH Reaction.

A kind of nano-ZSM-5 zeolite crystal was synthesized by the hydrothermal method, and HZSM-5 zeolite powder was obtained via acid exchange. By using pseudoboehmite as a binder, a series of HZSM-5 zeolite catalysts for methanol-to-hydrocarbons (MTH) were prepared through adjusting the binder content between 20 and 50% in addition to the molding method of wet extrusion and mechanical mixing. XRD, 27Al NMR, SEM-EDS, ICP, low-temperature N2 adsorption and desorption, NH3-TPD, Py-FTIR, FT-IR, TG and elemental analyses were used to characterize the properties of fresh catalysts and coke-deposited catalysts. Then, MTH catalytic performance was evaluated in a continuous-flow fixed-bed reactor. The characterization and evaluation results showed that the addition of dilute nitric acid during the molding process increased the amount of moderate-strength acid and formed a hierarchical pore distribution, which helped to reduce the reaction ability of cracking, aromatization and hydrogen transfer, improve the diffusion properties of the catalyst and slow down the coke deposition rate. The catalyst with a binder content of 30% made by wet extrusion with dilute nitric acid had the best performance, whose activity stability of MTH increased by 96 h, higher than other catalysts, and the coke deposition rate was slower, which was due to the most suitable distribution of acid strength and B/L ratio as well as the most obvious hierarchical pore structure.

A Self-Bleaching Electrochromic Mirror Based on Metal Organic Frameworks.

Metal-organic frameworks (MOFs) are considered to be the most promising positive anode materials to store charge for electrochromic devices. Nevertheless, a detailed mechanism of the electrochemical and ions storage process has not yet been revealed. Herein, the electrochemical mechanism of the highly porous ZIF-67 films and the electrochromic performance of electrochromic mirrors constructed from ZIF-67 and WO3 electrodes were investigated. The mechanism of the charge storage was revealed in the kinetic analysis of the Li-ion behavior based on the cyclic voltammetry curves and electrochemical impedance spectra. Impressively, the electrochromic mirrors with the self-bleaching effect and self-discharge behavior showed a unique electrochromic performance, such as a high coloration efficiency of 16.47 cm2 C-1 and a maximum reflectance modulation of 30.10% at 650 nm. This work provides a fundamental understanding of MOFs for applications in electrochromic devices and can also promote the exploration of novel electrode materials for high-performance reflective electrochromic devices.

Extraction and control of permittivity of hyperbolic metamaterials with optical nonlocality.

Metal nanorod arrays exhibit hyperbolic dispersion and optical nonlocality under certain conditions. Therefore, their optical behaviors can hardly be expressed by incident-angle-independent effective permittivity. Here we extract effective permittivity of silver nanorod arrays with diameters of 4 nm, 12 nm, and 20 nm by polarized transmission method in the visible range. The incident angles are chosen from 20° to 60° to study the influence of optical nonlocality on permittivity. We demonstrate how the diameter of the nanorods can control the effective permittivity beyond the effective medium theory. The results suggest that the effective permittivity gradually loses its accuracy as the diameter increases due to the optical nonlocality. Our experiment verifies that ultrathin nanorod arrays can resist the fluctuations caused by changes in incident angle. We also extract k-dependent effective permittivity of nanorods with larger diameters.

Clinical Manifestations, Fluid Changes and Neuroimaging Alterations in Patients with General Paresis of the Insane.

PURPOSE: We aim to study the clinical manifestations, fluid changes and neuroimaging alterations in patients with general paresis of the insane (GPI). METHODS: A total of 119 patients suffering from GPI recruited in Beijing Ditan Hospital, Capital Medical University from 2010 to 2020 were retrospectively analyzed. RESULTS: In 119 GPI patients, 103 cases (86.6%) were male. Misdiagnosed rate was up to 83.2%, schizophrenia and mood disorders were the most common misdiagnosed diseases. Duration from symptom onset to the final confirmed diagnosis was 10.4±12.9 months. The main clinical manifestations included cognitive impairment (114 cases, 95.8%) and neuropsychiatric symptoms (107 cases, 90.0%). The cognitive domains including the delayed recall, visuospatial/executive function and language ability indicated by MoCA score were damaged severely. Rapid plasma regain (RPR) of all GPI patients was 100% positive in serum and 89.9% positive in cerebral spinal fluid (CSF). The white blood cell (WBC) number in CSF was between 6 and 50/µL in 73 GPI patients (61.3%). The protein level was between 45.1 and 70mg/dL in 47 cases (39.5%). In the 110 cases, 96 cases (87.3%) were abnormal indicated by cerebral atrophy mostly located in the anterior brain and abnormal signals distributed in various regions of the brain mostly in the frontal lobe and temporal lobe. CONCLUSION: The symptoms of GPI were complex and easy to misdiagnose. The clinicians were still short of vigilance for neurosyphilis. We should expand serologic testing for syphilis especially in patients with cognitive impairment and neuropsychiatric symptoms. We suggest syphilis curricula in the training program of the clinicians especially for neurologist and psychiatrist.

Correlations of apathy with clinical symptoms of Alzheimer's disease and olfactory dysfunctions: a cross-sectional study.

BACKGROUND: Apathy is one of the most common symptoms of Alzheimer's disease (AD), however, correlations of apathy with demographic variables, cognitive functions, neuropsychiatric symptoms, activity of daily living and olfactory functions in AD patients are still lacking comprehensive investigations. METHODS: This is a cross-sectional study. Total 124 typical AD patients were consecutively recruited from April 2014 to April 2017. In 124 AD patients, 47 cases (37.9%) were male and 77 cases were female; patients' age were 43-93 years with an average of 68 years. Patients were divided into AD with apathy (AD-A) and AD with no apathy (AD-NA) groups according to the score of Modified Apathy Evaluation Scale, then were evaluated cognitive functions, neuropsychiatric symptoms and activity of daily living, and tested olfactory functions. Above variables were compared between AD-A and AD-NA groups. Further correlation analyses and linear regression analysis were performed between apathy and above variables. RESULTS: Compared with AD-NA group, global cognitive level, verbal memory, verbal fluency and activity of daily living were significantly compromised in AD-A group (P < 0.002); depression and agitation were severely displayed in AD-A group (P < 0.002). Apathy was negatively correlated with global cognitive function, verbal memory, verbal fluency and activity of daily living (P < 0.05). There was no significant difference of olfactory functions between the two groups (P > 0.002), and correlations between apathy and olfactory threshold, olfactory identification and global olfactory function were significant (P < 0.05) but quite weak (|r| < 0.3). Further linear regression analysis showed that only verbal fluency and instrumental activities of daily living were independently associated with apathy. CONCLUSIONS: Independent correlations among apathy, verbal fluency and instrumental activities of daily living in AD patients might be related to the common brain area involved in their pathogeneses.

Cerebrospinal Fluid Cytokines in Patients with Neurosyphilis: The Significance of Interleukin-10 for the Disease.

The aim of this study was to examine the cerebrospinal fluid (CSF) concentrations of proinflammatory and anti-inflammatory cytokines in neurosyphilis (NS), analyze the differences between asymptomatic NS (ANS) and symptomatic NS (SNS), and explore the diagnostic value of these cytokines. We enrolled 45 patients with a diagnosis of NS, including 18 patients with ANS and 27 patients with SNS, whose cerebrospinal fluid (CSF) samples were collected before penicillin therapy. Twelve patients with syphilis but non-NS (NNS) were also included. We measured the CSF levels of interleukin- (IL-) 1ß, IL-4, IL-6, IL-10, IL-17A, IL-21, and tumor necrosis factor- (TNF-) α; the CSF levels of the microglial activation marker soluble triggering receptor expressed on myeloid cells 2 (sTREM2); and the CSF levels of the neuronal injury marker neurofilament light proteins (NFL) using the human cytokine multiplex assay or ELISA. Of the measured cytokines in the CSF, only IL-10 levels were significantly increased in NS patients compared to NNS patients (p < 0.001). In a subgroup analysis, the CSF levels of IL-10 were significantly elevated in SNS patients compared to ANS and NNS patients (p = 0.024 and p < 0.001, respectively). The CSF IL-10 levels had a significant correlation with the markers of microglial activation and neuronal injury, and they also correlated with CSF rapid plasma reagin (RPR) titer, CSF white blood cell (WBC) count, and CSF protein concentration. The areas under the ROC curve (AUC) of CSF IL-10 in the diagnosis of NS and ANS were 0.920 and 0.891, respectively. The corresponding sensitivities/specificities were 86.7%/91.7% and 83.3%/91.7%, respectively. Therefore, the excessive production of IL-10 might facilitate bacterial persistent infection, play an important role in the pathogenesis of NS, and associate with the progression of the disease. CSF IL-10 concentration had a useful value in the diagnosis of NS, especially in ANS.

Clinical features and brain structural changes in magnetic resonance imaging in Alzheimer's disease patients with apathy.

BACKGROUND: Apathy is common in Alzheimer's disease (AD) patients. However, its relation with other clinical symptoms in AD and brain structural changes in magnetic resonance imaging is unclear. RESULTS: Compared with AD with no apathy group, cognitive function and activities of daily living were significantly impaired and neuropsychiatric symptoms were obviously presented in AD with apathy group (P<0.05). The frequency of Apolipoprotein E genotypes was not significantly different (P>0.05). Correlation analyses and multiple linear analyses revealed that thickness of left temporal pole and volume of posterior corpus callosum were significantly and negatively correlated with Modified Apathy Estimation Scale score in AD patients (P<0.05). CONCLUSIONS: Apathy with AD is positively correlated with cognitive impairment, neuropsychiatric symptoms and poor activities of daily living. Atrophy of left temporal pole and posterior corpus callosum presented by MRI is positively related with apathy of AD. METHODS: In this study, 137 AD patients were recruited and divided into AD with apathy group and AD with no apathy group according to Modified Apathy Estimation Scale score. We evaluated patients' cognitive function, neuropsychiatric symptoms and activities of daily living, detected the frequency of Apolipoprotein E genotypes and measured cortical thickness and volume by magnetic resonance imaging (MRI).

Increased CSF Soluble TREM2 Concentration in Patients With Neurosyphilis.

Objective: To explore cerebrospinal fluid (CSF) levels of soluble triggering receptor expressed on myeloid cells 2 (sTREM2) and neurofilament light proteins (NFL) in patients with neurosyphilis (NS). Methods: We enrolled 71 NS patients (41 early-NS and 30 late-NS patients) and 20 syphilis but non-NS patients whose CSF samples were collected. The CSF levels of the microglial activation biomarker sTREM2 and neuronal injury biomarker NFL were measured using ELISA. Results: CSF sTREM2 levels were significantly higher in NS patients compared to those in syphilis/non-NS patients (p < 0.001). In a subgroup analysis, the CSF sTREM2 levels elevated significantly in late-NS patients than those in early-NS patients (p < 0.001). The CSF sTREM2 levels in early-NS group were also significantly higher than those in syphilis/non-NS group (p = 0.024). Like CSF sTREM2, similar differences between groups were also found in CSF NFL. There was a moderate correlation between CSF sTREM2 and CSF NFL (r = 0.406, p < 0.001) in NS group. Conclusions: CSF sTREM2 levels elevated in NS and peaked at the late stage, suggesting that CSF sTREM2 may be a useful marker to quantify microglia activation in NS and may play a role in the progression of NS. The positive correlation between CSF sTREM2 and CSF NFL indicates a linkage between microglial activation and neuronal injury in NS.

Clinical and Laboratory Characteristics of Symptomatic and Asymptomatic Neurosyphilis in HIV-Negative Patients: A Retrospective Study of 264 Cases.

A retrospective study was performed to compare the differences in clinical and laboratory features of asymptomatic neurosyphilis (ANS) and symptomatic neurosyphilis (SNS). A total of 264 HIV-negative inpatients with neurosyphilis were enrolled from Beijing Ditan Hospital and Beijing Tiantan Hospital between January 2014 and May 2018, including 110 SNS and 154 ANS. The SNS group had more patients in males, older median age and without antisyphilis treatment than ANS group (P<0.001, P<0.001, and P<0.001, respectively). The laboratory findings showed that the SNS group had higher pretreatment serum rapid plasma regain (RPR) titer, current serum RPR titer, cerebrospinal fluid (CSF) white blood cell (WBC) counts, CSF protein concentrations, and higher positive CSF RPR rate than those in the ANS group (P=0.011, P<0.001, P<0.001, P<0.001, and P<0.001, respectively). The multivariate logistic regression analysis revealed that male (OR=2.833, P=0.009), age≥45 years (OR=3.611, P=0.001), without antisyphilis treatment (OR=0.247, P<0.001), higher current serum RPR titer (OR=1.373, P=0.022), positive CSF RPR (OR=4.616, P<0.001), and higher CSF protein concentration (OR=1.017, P=0.026) were independent risk predictors for SNS. Therefore, clinical and laboratory features between SNS and ANS are quietly different. Male gender, age≥45 years, and lack of antisyphilis treatment are risk factors for SNS. The elevated level of serum RPR titer, CSF protein concentration, and CSF RPR titer may indicate the development of neurosyphilis and the aggravation of neurological symptoms.

Broadband hyperbolic metamaterial covering the whole visible-light region.

Nanowire-based hyperbolic metamaterials (HMMs) with rich optical dispersion engineering capabilities are promising for use in miniaturization devices, such as nanophotonic chips and circuits. Herein, based on a one-step and template-free sputtering method, we are capable of precisely tuning the microstructural parameters of Ag nanowires (with a diameter <10 nm) in silica matrix, offering plenty of opportunities to perform hyperbolic dispersion engineering. Thus, the effective plasma frequency of the designed HMMs was shifted into the near-ultraviolet region (∼350 nm), leading to a broadband hyperbolic dispersion feature covering the whole visible-light region. This demonstration could pave the way for the development of metamaterial-based flat lenses, deep-subwavelength waveguiding, and broadband perfect absorbers and sensing, etc.

Electrochromism of Nanocrystal-in-Glass Tungsten Oxide Thin Films under Various Conduction Cations.

The nanocrystal-in-glass (nanocrystals embedded amorphous matrix) tungsten oxide (WO3) thin films with a nanoporous characteristic were prepared via an electron beam evaporation technique. The e-beam evaporated WO3 thin films present a fast colored/bleached time of 16/11, 16/14, and 12/12 s, a large optical modulation of 92, 91, and 87% at 633 nm, and a high coloration efficiency of 61.78, 62.04, and 67.59 cm2 C-1 in Li+, Na+, and Al3+ electrolytes, respectively. On one hand, the improved electrochromic performance is mainly attributed to the short diffusion distance and buffering effect in the host matrix, which facilitates the ion insertion/extraction and alleviates the structural collapse of the framework. On the other, owing to the strong electrostatic interactions between the trivalent cations and the host, the WO3 thin films in Al3+ possess a shallow diffusion depth and long cycle life. The individual contribution from the capacitance- or diffusion-controlled process is comprehensively demonstrated. Pseudocapacitive behavior in the nanocrystal-in-glass WO3 thin films is in favor of fast kinetics response and sound cycling stability. Our work offers an in-depth insight of the electrochromic mechanism for nanocrystal-in-glass WO3 thin films in various electrolytes and sheds light on the fundamental principle in the electrochromic devices.

A Flexible Caterpillar-Like Gold Nanoparticle Assemblies with Ultrasmall Nanogaps for Enhanced Dual-Modal Imaging and Photothermal Therapy.

Gold nanoparticle (AuNP) assemblies (GNAs) have attracted attention since enhanced coupling plasmonic resonance (CPR) emerged in the nanogap between coupling AuNPs. For one dimensional GNAs (1D-GNAs), most CPR from the nanogaps could be easily activated by electromagnetic waves and generate drastically enhanced CPR because the nanogaps between coupling AuNPs are linearly distributed in the 1D-GNAs. The reported studies focus on the synthesis of 1D-GNAs and fundamental exploration of CPR. There are still problems which impede further applications in nanomedicine, such as big size (>500 nm), poor water solubility, and/or poor stability. In this study, a kind of 1D flexible caterpillar-like GNAs (CL-GNAs) with ultrasmall nanogaps, good water solubility, and good stability is developed. The CL-GNAs have a flexible structure that can randomly move to change their morphology, which is rarely reported. Numerous ultrasmall nanogaps (<1 nm) are linearly distributed along the structure of CL-GNAs and generate enhanced CPR. The toxicity assessments in vitro and vivo respectively demonstrate that CL-GNAs have a low cytotoxicity and good biocompatibility. The CL-GNAs can be used as an efficient photothermal agent for photothermal therapy, a probe for Raman imaging and photothermal imaging.