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Atomically thin oxide semiconductors are emerging as potential materials for their potentiality in monolithic 3D integration and sensor applications. In this study, a charge transfer method employing viologen, an organic compound with exceptional reduction potential among n-type organics, is presented to modulate the carrier concentration in atomically thin In2O3without the need of annealing. This study highlights the critical role of channel thickness on doping efficiency, revealing that viologen charge transfer doping is increasingly pronounced in thinner channels owing to their increased surface-to-volume ratio. Upon viologen doping, an electron sheet density of 6.8 × 1012cm–2is achieved in 2 nm In2O3back gate device while preserving carrier mobility. Moreover, by the modification of the functional groups, viologens can be conveniently removed with acetone and an ultrasonic cleaner, making the viologen treatment a reversible process. Based on this doping scheme, we demonstrate an n-type metal oxide semiconductor inverter with viologen-doped In2O3, exhibiting a voltage gain of 26 at VD= 5 V. This complementary pairing of viologen and In2O3offers ease of control over the carrier concentration, making it suitable for the next-generation electronic applications.

Fuzzy neural networks (FNNs) have been very successful at handling uncertainty in data using fuzzy mappings and if-then rules. However, they suffer from generalization and dimensionality issues. Although deep neural networks (DNNs) represent a step toward processing high-dimensional data, their capacity to address data uncertainty is limited. Furthermore, deep learning algorithms designed to improve robustness are either time consuming or yield unsatisfactory performance. In this article, we propose a robust fuzzy neural network (RFNN) to overcome these problems. The network contains an adaptive inference engine that is capable of handling samples with high-level uncertainty and high dimensions. Unlike traditional FNNs that use a fuzzy AND operation to calculate the firing strength for each rule, our inference engine is able to learn the firing strength adaptively. It also further processes the uncertainty in membership function values. Taking advantage of the learning ability of neural networks, the acquired fuzzy sets can be learned from training inputs automatically to cover the input space well. Furthermore, the consequent layer uses neural network structures to enhance the reasoning ability of the fuzzy rules when dealing with complex inputs. Experiments on a range of datasets show that RFNN delivers state-of-the-art accuracy even at very high levels of uncertainty. Our code is available online. https://github.com/leijiezhang/RFNN

Geometry optimization is a crucial step in computational chemistry, and the efficiency of optimization algorithms plays a pivotal role in reducing computational costs. In this study, we introduce a novel reinforcement-learning-based optimizer that surpasses traditional methods in terms of efficiency. What sets our model apart is its ability to incorporate chemical information into the optimization process. By exploring different state representations that integrate gradients, displacements, primitive type labels, and additional chemical information from the SchNet model, our reinforcement learning optimizer achieves exceptional results. It demonstrates an average reduction of about 50% or more in optimization steps compared to the conventional optimization algorithms that we examined when dealing with challenging initial geometries. Moreover, the reinforcement learning optimizer exhibits promising transferability across various levels of theory, emphasizing its versatility and potential for enhancing molecular geometry optimization. This research highlights the significance of leveraging reinforcement learning algorithms to harness chemical knowledge, paving the way for future advancements in computational chemistry.

Distributed fuzzy neural networks (DFNNs) have attracted increasing attention recently due to their learning abilities in handling data uncertainties in distributed scenarios. However, it is challenging for DFNNs to handle cases in which the local data are nonindependent and identically distributed (non-IID). In this article, we propose a federated fuzzy neural network (FedFNN) with evolutionary rule learning (ERL) to cope with non-IID issues as well as data uncertainties. The FedFNN maintains a global set of rules in a server and a personalized subset of these rules for each local client. ERL is inspired by the theory of biological evolution; it encourages rule variations while activating superior rules and deactivating inferior rules for local clients with non-IID data. Specifically, ERL consists of two stages in an iterative procedure: a rule cooperation stage that updates global rules by aggregating local rules based on their activation statuses and a rule evolution stage that evolves the global rules and updates the activation statuses of the local rules. This procedure improves both the generalization and personalization of the FedFNN for dealing with non-IID issues and data uncertainties. Extensive experiments conducted on a range of datasets demonstrate the superiority of the FedFNN over state-of-the-art methods.

The large amount of data is one challenge in electroencephalogram (EEG) analysis, in which the channel Two Dimensional (2-D), time One Dimensional (1-D), and spectral (1-D) are generally considered. Convolutional neural networks (CNNs) have drawn much attention for automatic feature learning in various fields. Meanwhile, many studies have demonstrated integration from multiple sources and decisions could boost performance. However, CNN for EEG analysis usually involves millions of parameters, which easily leads to overfitting. A new model of a multistream Three Dimensional (3-D) CNN with parameter sharing is proposed for EEG. Two EEG data sets: 1) the lane-keeping task (LKT) data set and 2) sleep data set are applied. For the LKT data set, the proposed multistream 3-D CNN with parameter sharing model achieves 0.5486 root-mean-square error (RMSE), showing improvement by at least 2.77% compared to the other approaches. In the sleep data set, the error rate of the proposed model was 24.65%, showing at least 10.28% improvement in performance compared to the other methods. The lower RMSE and error rate show that the multistream 3-D CNN with parameter sharing model efficiently extracts significant features from EEG data. Moreover, the sharing mechanism even reduces the risk of overfitting and the number of parameters by comprehending common representations among multiple streams.

ObjectivesSodium-glucose cotransporter-2 inhibitors (SGLT2i) reduce heart failure (HF) in at-risk patients and may possess antitumour effects. We examined the effect of SGLT2i on HF and mortality among patients with cancer and diabetes.MethodsThis was a retrospective propensity score-matched cohort study involving adult patients with type 2 diabetes mellitus diagnosed with cancer between January 2010 and December 2021. The primary outcomes were hospitalisation for incident HF and all-cause mortality. The secondary outcomes were serious adverse events associated with SGLT2i.ResultsFrom a total of 8640 patients, 878 SGLT2i recipients were matched to non-recipients. During a median follow-up of 18.8 months, SGLT2i recipients had a threefold lower rate of hospitalisation for incident HF compared with non-SGLT2i recipients (2.92 vs 8.95 per 1000 patient-years, p=0.018). In Cox regression and competing regression models, SGLT2i were associated with a 72% reduction in the risk of hospitalisation for HF (HR 0.28 (95% CI: 0.11 to 0.77), p=0.013; subdistribution HR 0.32 (95% CI: 0.12 to 0.84), p=0.021). The use of SGLT2i was also associated with a higher overall survival (85.3% vs 63.0% at 2 years, p<0.001). The risk of serious adverse events such as hypoglycaemia and sepsis was similar between the two groups.ConclusionsThe use of SGLT2i was associated with a lower rate of incident HF and prolonged overall survival in patients with cancer with diabetes mellitus.

TiO2nanostructures (NSs) doped with varying Fe concentrations are synthesized using the sol-gel process, followed by annealing in 1 atm environment at 470 ℃ for 3 h. Anatase TiO2crystal structure and defect levels are characterized using XRD, HRTEM, SEM-EDS, XPS, Raman, EPR, PL, and TR-PL techniques. Remarkably, the addition of approximately 4 wt% Fe dopant had no discernible impact on the crystal structure of the anatase TiO2. Furthermore, energy levels including VO, Tii∙∙∙, Fe3+/Fe2+, Fe3+/Fe4+, and Ti3+/Ti4+are identified. The optical band-gap of TiO2is reduced from 3.077 to 2.352 eV and its carrier lifetime is extended from 6.53 ns to 9.12 ns with Fe contents ranging from 0 to approximately 2 wt%. The CO2photoreduction results demonstrate that Fe-doped TiO2outperforms commercial TiO2(P25) in terms of the photoreduction rate. Particularly, TiO2NSs doped with 2 wt% Fe exhibit the highest CO2photoreduction rates, yielding approximately 35.19×102and 66.84×102μmol‧g1‧min1of CO and CH4, respectively; thereby surpassing P25 by factors of 1.26 and 3.1, respectively. Therefore, Fe-doping can reduce the optical band-gap and extend the carrier lifetime of TiO2photocatalysts, resulting in superior CO2photoreduction capabilities. Moreover, the significance of electrons in the CO2photoreduction process, as evidenced by the findings from the EPR spectrum and CO2photoreduction, underscores the importance of an appropriate Fe content, such as 2 wt% used in this study, for enhancing the photoreduction abilities and potential applications of TiO2in CO2photoreduction.

• The sizes of Al-doped ZnO@SnO 2 can be effectively controlled by SnO 2 precursors. • Al-doped ZnO@SnO 2 heteronanowires exhibited the higher photocatalytic performance. • Al-doped ZnO@SnO 2 @Ag heteronanowires revealed higher SERS enhancement and reusability. • The SERS substrate also exhibited very low detection limit for R6G and amoxicillin. Bi-functional Al-doped ZnO@SnO 2 heteronanowires systematically analyzed as high-performance substrates for photocatalytic and surface-enhanced Raman scattering (SERS) applications. For the photocatalytic application, the Al-doped ZnO@SnO 2 heteronanowires can exhibit highly efficient and reusable photocatalysts in the photodecomposition of rhodamine 6G solution under low-powered UV-light irradiation, which ascribed to improve the inhabitation of electron–hole pairs recombination and higher surface active sites. For the SERS application, Al-doped ZnO@SnO 2 heteronanowires revealed suitable geometry to deposit Ag nanoparticles with higher density and more hot spots in three-dimensional structures, which can provide high SERS enhancement, low detection limit (amoxicillin 10−10 M), high reproducibility, and stability. [ABSTRACT FROM AUTHOR]

Quantum thermodynamics is emerging both as a topic of fundamental research and as a means to understand and potentially improve the performance of quantum devices1–10. A prominent platform for achieving the necessary manipulation of quantum states is superconducting circuit quantum electrodynamics (QED)11. In this platform, thermalization of a quantum system12–15can be achieved by interfacing the circuit QED subsystem with a thermal reservoir of appropriate Hilbert dimensionality. Here we study heat transport through an assembly consisting of a superconducting qubit16capacitively coupled between two nominally identical coplanar waveguide resonators, each equipped with a heat reservoir in the form of a normal-metal mesoscopic resistor termination. We report the observation of tunable photonic heat transport through the resonator–qubit–resonator assembly, showing that the reservoir-to-reservoir heat flux depends on the interplay between the qubit–resonator and the resonator–reservoir couplings, yielding qualitatively dissimilar results in different coupling regimes. Our quantum heat valve is relevant for the realization of quantum heat engines17and refrigerators, which can be obtained, for example, by exploiting the time-domain dynamics and coherence of driven superconducting qubits18,19. This effort would ultimately bridge the gap between the fields of quantum information and thermodynamics of mesoscopic systems. The state of a superconducting circuit qubit governs the photonic heat flow through an integrated assembly, constituting a quantum heat valve that provides a testbed for exploring quantum thermodynamics in a circuit quantum electrodynamics setting.

ABSTRACTThis study has investigated the influence of physiographic factors upon the probability of slide occurrence in the Kaoping River Basin. According to previous literature, statistical tests, and physical mechanisms, three physiographic factors (slope steepness, the dip slope ratio, and the time-dependent landslide ratio) were significantly related to slide occurrence. These were combined with hydrological factors (cumulative rainfall) to establish an assessment model for estimating the probability of slide occurrence using logistic regression. The model’s overall accuracy in the training and validation stages was about 81%. Overall, 20 randomly selected historical rainfall events were employed for verification, including 10 events each with and without slide occurrence. The results showed that the model accuracy was approximately 80%, if the probability threshold Pshis set to be 0.5.This assessment model can assist in prediction of slide occurrence and the proposed subsequent engineering measures or vegetation restoration is often able to reduce the landslide ratio and the probability of slide occurrence. After landform changes, the model’s physiographic factors can be updated to adjust the rainfall threshold for slide occurrence. Given an appropriate cumulative rainfall and an acceptable risk of slide occurrence, the model can identify priority regions for slide prevention.

Abnormal biochemical alteration such as unbalanced reactive oxygen species (ROS) levels has been considered as a potential disease-specific trigger to deliver therapeutics to target sites. However, in view of their minute variations in concentration, short lifetimes, and limited ranges of action, in situ generation of ROS with specific manipulations should be more effective for ROS-responsive drug delivery. Here we present a new delivery nanoplatform for photodynamic therapy (PDT) with on-demand drug release regulated by light irradiation. Rose bengal (RB) molecules, which exhibit a high yield of ROS generation, were encapsulated in a mixture of chitosan (CTS), poly(vinyl alcohol) (PVA), and branched polyethylenimine (bPEI) with hydrophobic iron oxide nanoparticles through an oil-in-water emulsion method. The as-prepared magnetic nanoclusters (MNCs) with a tripolymer coating displayed high water dispersibility, efficient cellular uptake, and the cationic groups of CTS and bPEI were effective for RB loading through electrostatic interaction. The encapsulation efficiency of RB in MNCs could be further improved by increasing the amount of short bPEI chains. During the photodynamic process, controlled release of the host molecules (i.e., RB) or guest molecules (i.e., paclitaxel) from the bPEI-based nanoplatform was achieved simultaneously through a photooxidation action sensitized by RB. This approach promises specific payload release and highly effective PDT or PDT combined therapy in various cancer cell lines including breast (MCF-7 and multidrug resistant MCF-7 subline), SKOV-3 ovarian, and Tramp-C1 prostate. In in vivo xenograft studies, the nanoengineered light-switchable carrier also greatly augments its PDT efficacy against multidrug resistant MCF-7/MDR tumor as compared with free drugs. All the above findings suggest that the substantial effects of enhanced drug distribution for efficient cancer therapy was achieved with this smart nanocarrier capable of on demand drug release and delivery, thus exerting its therapeutic activity to a greater extent.

The Industrial Technology Research Institute has developed a 30 kWthmoving bed chemical looping system for hydrogen production. Methane is supplied as a fuel to the reducer, and steam is supplied to the oxidizer to produce hydrogen. An iron-based oxygen carrier is used circulating between the reactors. In this study, the mechanical strength, attrition rate, and conversion rate of the oxygen carrier were tested at two Fe2O3levels of content (40 and 60 wt %) calcined at temperatures of 1100 and 1300 °C. The oxygen carrier with the lower iron content presented the higher conversion rate of 72% at both calcination temperatures. The mechanical strength (170.5 N) and attrition rate (0.3%) of the oxygen carrier with a low Fe2O3content were higher at the higher calcination temperature. Further, the oxygen carriers were circulated in the 30 kWthmoving bed chemical looping system under ambient and high-temperature conditions. The oxygen carrier with two Fe2O3content levels (40 and 60 wt %) at the calcination temperature of 1200 °C was employed in the attrition rate test conducted in the chemical looping system. Under the ambient temperature conditions, the average attrition rate of the oxygen carrier with a lower Fe2O3content was lower (0.16%) than that of the oxygen carrier with a higher Fe2O3content (0.24%). Moreover, the test results show the operating temperature has a lower level of influence on the attrition rate of the oxygen carrier.

To realize a finger positioning device, as called “virtual mouse,” to replace a touchpad, touchscreen, or even real mouse, current positioning technologies cannot achieve a sufficient resolution, a compact volume, and a simple detection algorithm simultaneously. For this problem, using a light‐emitting diode source, two lens arrays, and two light sensors, we design and implement a virtual mouse prototype. The optical architecture is carefully determined for a compact volume, a sufficient resolution, and a high detection accuracy. Corresponding to a compact system volume of 3.1 mm (thickness) × 4.5 mm (length) × 2, a theoretical resolution higher than 25 pixels per inch (ppi) can be obtained over a working area of 10 cm × 10 cm. Experiments are also implemented, in which a mean detection error of 0.24 cm that corresponds to approximately two distinguishable points, and a minimal resolution of 26 ppi over the whole working area are verified. If the system thickness is relaxed to 25 mm, a resolution higher than 200 ppi can be achieved. The proposed virtual mouse, which is simple enough and potential to be extended for three‐dimensional position detection, can be integrated with a flat panel display to achieve a compact display application that can interact with users. A virtual mouse using lens arrays and light sensors is proposed for finger positioning. Experiments verify a high resolution of 26 ppi over a working area of 10 cm × 10 cm. The system volume is as compact as 3.1 mm (thickness) × 4.5 mm (length) × 2, while multiple imaging paths guarantee an acceptable accuracy of approximately two distinguishable points.

The desirable features for a portable 3D display include displaying 2D and 3D images without resolution degradation for multiple users, a 2D/3D switchable functionality, and, in particular, a compact volume. To produce a portable 3D display with these desirable features, we propose here a multi-user 3D film combined with a side-emission backlight system that has a directional-sequential light distribution. According to the simulation and experimental results, the multi-user 3D film successfully uses an inverted trapezoid structure to separate the rays of each light source and increases the number of observers from one to three. Additionally, the specification of the inverted trapezoid structure can be determined via equations for different designated viewing positions of the side observer and for the ratio of light intensities for the central and side observers.

Introduction:Patients with cancer face a heightened risk of cardiovascular (CV) events and mortality. Sodium-glucose cotransporter 2 inhibitors (SGLT2i) reduce CV events in at-risk patients and may possess antitumor effects. Therefore, we examined the effect of SGLT2i on CV events and mortality among patients with cancer and diabetes.Methods:This was a retrospective propensity score-matched cohort study conducted at two tertiary referral centers in Taiwan. We included all adult patients with type 2 diabetes mellitus diagnosed with cancer between January 2010 and December 2021. The primary outcomes were hospitalization for incident heart failure (HF) and all-cause mortality. The secondary outcomes were a composite of myocardial infarction, ischemic stroke, and cardiac arrhythmias, and serious adverse events associated with SGLT2i.Results:From a total of 8640 patients, 878 SGLT2i-recipients were matched to non-recipients. During a median follow-up period of 18.8 months, SGLT2i recipients had a lower rate of hospitalization for incident HF compared with non-SGLT2i recipients (2.92 vs. 8.95 per 1000 patient-years, p=0.018). In both Cox regression and competing regression models, SGLT2i were associated with a 70% reduction in the risk for hospitalization for incident HF (HR, 0.28 [95% CI: 0.11-0.77], p = 0.013; SHR, 0.32 [95% CI: 0.12-0.84], p = 0.021). The use of SGLT2i was associated with a higher overall survival (85.3% vs. 63.0% at 2 years, p<0.001). The risk of myocardial infarction, ischemic stroke, cardiac arrhythmias, and serious adverse events such as hypoglycemia, urosepsis, and sepsis was similar between the SGLT2i and non-SGLT2i cohorts.Conclusions:The use of SGLT2i was associated with a lower rate of hospitalization for incident HF and prolonged overall survival in cancer patients with diabetes mellitus.

A simple hydrothermal method with titanium tetraisopropoxide (TTIP) as a precursor and triethanolamine (TEOA) as a chelating agent enabled growth in the presence of a base (diethylamine, DEA) of anatase titania nanocrystals (HD1–HD5) of controlled size. DEA played a key role to expedite this growth, for which a biphasic crystal growth mechanism is proposed. The produced single crystals of titania show octahedron-like morphology with sizes in a broad range of 30–400 nm; a typical, extra large, octahedral single crystal (HD5) of length 410 nm and width 260 nm was obtained after repeating a sequential hydrothermal treatment using HD3 and then HD4 as a seed crystal. The nanocrystals of size ∼30 nm (HD1) and ∼300 nm (HD5) served as active layer and scattering layer, respectively, to fabricate N719-sensitized solar cells. These HD devices showed greater VOCthan devices of conventional nanoparticle (NP) type; the overall device performance of HD attained an efficiency of 10.2% power conversion at a total film thickness of 28 μm, which is superior to that of a NP-based reference device (η = 9.6%) optimized at a total film thickness of 18–20 μm. According to results obtained from transient photoelectric and charge extraction measurements, this superior performance of HD devices relative to their NP counterparts is due to the more rapid electron transport and greater TiO2potential.

ATP-binding cassette transporter A1 (ABCA1) plays a crucial role in exporting cholesterol from macrophages, a function relevant to its involvement in the prevention of atherosclerosis. Quercetin, one of flavonoids, has been described to reduce atherosclerotic lesion formation. This study is aimed to investigate the effect of quercetin on regulation of ABCA1 expression and to explore its underlying mechanisms in macrophages. The results show that quercetin markedly enhanced cholesterol efflux from macrophages in a concentration-dependent manner, which was associated with an increase in ABCA1 mRNA and protein expression. Remarkably, quercetin is able to stimulate the phosphorylation of p38 by up to 234-fold at 6 h via an activation of the transforming growth factor β-activated kinase 1 (TAK1) and mitogen-activated kinase kinase 3/6 (MKK3/6). Inhibition of p38 with a pharmacological inhibitor or small hairpin RNA (shRNA) suppressed the stimulatory effects of quercetin on ABCA1 expression and cholesterol efflux. Moreover, knockdown of p38 reduced quercetin-enhanced ABCA1 promoter activity and the binding of specificity protein 1 (Sp1) and liver X receptor α (LXRα) to the ABCA1 promoter using chromatin immunoprecipitation assays. These findings provide evidence that p38 signaling is essential for the regulation of quercetin-induced ABCA1 expression and cholesterol efflux in macrophages.

We review systematically the kinetic characterisation of electron transport and charge recombination in dye-sensitised solar cells (DSSC) using both temporally resolved and frequency-domain techniques. For the temporally resolved approach, charge extraction (CE), transient-photocurrent decay (TCD) and transient-photovoltage decay (TVD) methods are introduced in detail; for the frequency-domain approach, techniques involving electrochemical impedance spectroscopy (EIS), intensity-modulated photocurrent spectroscopy (IMPS) and intensity-modulated photovoltage spectroscopy (IMVS) are presented in detail. The TCD and TVD data are obtained under short-circuit and open-circuit conditions, respectively, and the electron diffusion coefficients and electron lifetimes are extracted from fitting the decay curves accordingly; the IMPS/IMVS results are the counterparts of the TCD/TVD results in the frequency domain. Even though the EIS results are readily acquired, an accurate interpretation of the data requires an appropriate model to determine the internal features of the device. This review provides an account of each technique about its operating principle, experimental setup and data analysis. As case studies for each technique, examples are given to rationalise the observed potential shift, decay coefficients of electron transport and of charge recombination in relation to the corresponding photovoltaic performance of the device.

An organic–organic blend thin film has been synthesized through the solution deposition of a triblock copolymer (Pluronic P123, EO20–PO70–EO20) and polystyrene (PS), which is called P123–PS for the blend film whose precursor solution was obtained with organic additives. In addition to having excellent insulating properties, these materials have satisfied other stringent requirements for an optimal flexible device: low-temperature fabrication, nontoxic, surface free of pinhole defect, compatibility with organic semiconductors, and mechanical flexibility. Atomic force microscope measurements revealed that the optimized P123–PS blend film was uniform, crack-free, and highly resistant to moisture absorption on polyimide (PI) substrate. The film was well-adhered to the flexible Au/Cr/PI substrate for device application as a stable insulator, which was likely due to the strong molecular assembly that includes both hydrophilic and hydrophobic effects from the high molecular weights. The contact angle measurements for the P123–PS surface indicated that the system had a good hydrophobic surface with a total surface free energy of approximately 19.6 mJ m–2. The dielectric properties of P123–PS were characterized in a cross-linked metal–insulator–metal structured device on the PI substrate by leakage current, capacitance, and dielectric constant measurements. The P123–PS film showed an average low leakage current density value of approximately 10–10A cm–2at 5–10 MV cm–1and large capacitance of 88.2 nF cm–2at 1 MHz, and the calculated dielectric constant was 2.7. In addition, we demonstrated an organic thin-film transistor (OTFT) device on a flexible PI substrate using the P123–PS as the gate dielectric layer and pentacene as the channel layer. The OTFT showed good saturation mobility (0.16 cm2V–1s–1) and an on-to-off current ratio of 5 × 105. The OTFT should operate under bending conditions; therefore flexibility tests for two types of bending modes (tensile and compressive) were also performed successfully.

The liquid crystal lenses system, which could be electrically controlled easily for autostereoscopic 2D/3D switchable display was proposed. The High-Resistance liquid crystal (HRLC) lens utilized less controlled electrodes and coated a high-resistance layer between the controlled-electrodes was proposed and was used in this paper. Compare with the traditional LC lens, the HR-LC Lens could provide smooth electric-potential distribution within the LC layer under driving status. Hence, the proposed HR-LC Lens had less circuit complexity, low driving voltage, and good optical performance also could be obtained. In addition, combining with the proposed driving method called dual-directional overdriving method, the above method could reduce the switching time by applying large voltage onto cell. Consequently, the total switching time could be further reduced to around 2second. It is believed that the LC lens system has high potential in the future.

Low-resistivity TiSi2nanowires were synthesized on silicon with TiF4precursor and without catalysts. The growth was found to follow vapor−solid mechanism. The single crystalline nanowires are of C54−TiSi2phase with the diameters and lengths being 20−50 nm and 1−2 micrometers, respectively. The field emission properties of the TiSi2nanowires were measured, and the turn on voltage is 8 V/μm when the current density attained 1 μA/cm2. The field enhancement factor is about 800 with the measured work function of 4.6 eV. In addition, long term stability of field emission was found. The resistivity of the TiSi2nanowire was measured to be 30 μΩ cm by the two-probe measurement. The metallic TiSi2nanowires exhibited a failure current density of as high as 3 × 108A/cm2. The low resistivity, high failure current density, and high field emission stability of the TiSi2nanowires indicate that they are potentially applicable in the interconnecting electronic architectures and silicon-based field emission devices.

Two-dimensional (2D) inverse opal ZnO nanorod networks exhibiting a photonic crystal band gap have been grown by an aqueous chemical method with nanosphere lithography at low temperatures. The 2D ZnO photonic crystals with band gap at the green light emission region have been successfully fabricated for the first time. The presence of the photonic band gap was inferred from the reflection spectra and confirmed by the photonic band calculation. The ZnO nanorod networks exhibit prominent blue shift at UV emission and almost no green emission attributed to singly ionized oxygen vacancies. The combination of aqueous chemical growth and nanosphere lithography provides a large-scale, facile, and low-cost fabrication method at low temperatures, which shall be of significant value for practical applications of the grown photonic crystals.

Bat-shaped nanorods (nanobats) of Ti5Si4were grown on titanium foil by a vapor and condensation method without catalysts. The average diameter of the heads and the tails of the nanobats as well as the length of the nanobats are 25, 15, and 350 nm, respectively. The resistivity of the Ti5Si4nanobat was measured to be 348 Ωμ·cm. Excellent field emission properties were found with the turn-on voltage of the Ti5Si4nanobats at the current density of 1 μA/cm2being 1.47 V/μm and field amplification factor being as high as 1350. The possession of remarkable field emission properties indicates that the Ti5Si4nanobats may be applicable as emitters in flat panel display and vacuum microelectronic devices.

The development of materials of ultralow high-temperature thermal conductivities for applications in high-temperature thermal insulations has become increasingly more important than ever in view of the ever worsening issues of fossil energy depletion and global warming that call for more demanding energy-saving practices. In this study, a new class of opacified monolithic aerogels of ultralow high-temperature thermal conductivities was developed for thermal insulation applications at high temperatures. Carbon nanofibers were successfully incorporated into the mesoporous network of silica aerogels at concentrations as high as 20 wt % through an accelerated-gelation sol−gel process to enhance the dimensional stability of the silica aerogels and to suppress the thermal radiations that become dominant at high temperatures, to achieve an ultralow thermal conductivity of 0.050 W/m-K at 500 °C, whereas maintaining a thermal stability above 500 °C (much better than the conventional high-temperature thermal insulation materials: 0.3 W/m-K at 500 °C for glass fibers, 0.1 W/m-K at 527 °C for alumina fused brick, and 1.7 W/m-K at 527 °C for sillimante).

Supercapacitive properties of Co/ZnCo oxide composite with a core–shell nanostructure (Co3O4/ZnCo2O4) prepared directly onto a nickel foam substrate by a two-step hydrothermal method were investigated. The synthesized core–shell structure consisted of some ∼40–100 nm in thick flaky ZnCo2O4deposits coated onto the surface of Co3O4nanorods measuring ∼150 nm in diameter. The specific capacitance value of the Co3O4/ZnCo2O4core–shell nanostructure synthesized by hydrothermal at 130 °C for a ZnCo2O4deposition time of 2 h can attain 1804 F g−1at a scan rate of 5 mV s−1. Furthermore, the core–shell structured electrode still exhibited a relatively good capacitance retention of more than 93% after 3000 CV cycles due to the superior structural support of Co3O4scaffolds. The Co3O4/ZnCo2O4core–shell structure exhibits excellent electrochemical performances and, as such, is one of the more promising active materials in pseudocapacitor applications.

A new strategy to introduce metallic dopant into ZnO structures by a wet chemical reaction is presented. Single-crystal Er-doped ZnO flower-like structures have been synthesized on ZnO-coated silicon substrate by a low temperature hydrothermal process. The Er-doped ZnO structures exhibit promising 1.54 μm photoluminescence emission for optoelectronic communication. The successful doping has been confirmed by the X-ray diffraction, transmission electron microscopy, X-ray photoemission spectroscopy and photoluminescence measurements. The achievement to introduce Er dopants into ZnO flower-like structures by the time- and cost-effective wet chemical reaction at low temperature for the first time has vast potential to scale up for possible applications. The photoluminescence properties are significantly improved compared to that reported in the literature for the Er-doped nanowires and thin films and shall be much more applicable in optical and communication devices. The flower-like structures are expected to be advantageous in serving as a multi-directional infrared emitters and/or detectors. (© 2008 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

The helix 69 (H69) region of the large subunit (28S) rRNA of Homo sapiens contains five pseudouridine (Psi) residues out of 19 total nucleotides (26%), three of which are universally or highly conserved. In this study, the effects of this abundant modified nucleotide on the structure and stability of H69 were compared with those of uridine. The role of a loop nucleotide substitution from A in bacteria (position 1918 in Escherichia coli 23S rRNA) to G in eukaryotes (position in 3734 in H. sapiens) was also examined. The thermodynamic parameters were obtained through UV melting studies, and differences in the modified and unmodified RNA structures were examined by 1H NMR and circular dichroism spectroscopy. In addition, a [1,3-15N]Psi phosphoramidite was used to generate H69 analogs with site-specific 15N labels. By using this approach, different Psi residues can be clearly distinguished from one another in 1H NMR experiments. The effects of pseudouridine on H. sapiens H69 are consistent with previous studies on tRNA, rRNA, and snRNA models in which the nucleotide offers stabilization of duplex regions through PsiN1H-mediated hydrogen bonds. The overall secondary structure and base-pairing patterns of human H69 are similar to the bacterial RNA, consistent with the idea that ribosome structure and function are highly conserved. Nonetheless, pseudouridine-containing RNAs have subtle differences in their structures and stabilities compared to the corresponding uridine-containing analogs, suggesting possible roles for Psi such as maintaining translation fidelity.

No relevant conflicts of interest to declare.