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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. [ABSTRACT FROM AUTHOR]

In conclusion, the finding that tumor genetics, pathology, and location are significantly correlated with language reorganization in brain tumor patients might contribute to the choice of the optimal surgical procedure and timing. Against this background, Pasquini et al. described a retrospective investigation of 405 patients with left-hemispheric tumors and 49 patients with right-hemispheric tumors as controls [[2]]. 8895248 2 Pasquini L, Yildirim O, Silveira P. Effect of tumor genetics, pathology, and location on fMRI of language reorganization in brain tumor patients. In terms of the effect of tumor location on language reorganization, significant associations exist between the frontal LI, Broca LI, and tumor involvement of Broca's area (BA). [Extracted from the article]

In this work, amorphous praseodymium-doped In-Sn-Zn-O (ITZO-Pr) thin-film transistors (TFTs) were fabricated with improved negative-bias illumination stress (NBIS) stability under different radio frequency (RF) magnetron sputtering powers. The optimized ITZO-Pr TFTs presented field effect mobility ($\boldsymbol {\mu }_{\text{FE}}$) of 20.9 cm $^{2}\cdot {}\text{V}^{-1}\cdot {}\text{s}$ −1, steep subthreshold (SS) of 0.27 V/dec, and small threshold voltage shift (${\Delta } {V}_{\text{th}} = -2.12$ V) under NBIS (−20 V, 3600 s). All Pr-doped devices exhibited a reduction in light responsivity of more than one order of magnitude compared with ITZO TFTs. Moreover, after Pr doping, relaxation processes of photoelectrons changed and then the activation energy (${E}_{\text{a}}$) of light-induced electrons relaxation decreased, which enhanced the NBIS stability of ITZO TFTs effectively. [ABSTRACT FROM AUTHOR]

High-field-effect-mobility InSnZnO thin-film transistors (TFTs) are prepared through Al-induced microstructure regularization (AIMR) at an annealing temperature lower to 400 °C. Spherical crystalline particles are distributed throughout the back channel near the Al layer, while an amorphous phase still represents the front channel but with enhanced microstructure ordering. Especially, the packing density is distinctly increased, and oxygen vacancies are largely reduced. The optimized TFT exhibits excellent performance with a steep sub-threshold swing of 0.18 V/dec, a high on/off current ratio of 2.5 × 108, a threshold voltage of −0.21 V, and a small threshold voltage shift of −0.24 V under negative bias stress (−20 V, 3600 s), especially a remarkable field-effect mobility boosted to 53.2 cm2/V s compared to 19.1 cm2/V s for the TFT without the Al layer. After Al removal, the TFT performance shows no obvious degradation, implying good compatibility of the AIMR technique to the current device process. [ABSTRACT FROM AUTHOR]

Amorphous gallium oxide (a-GaO x) thin films are fabricated via magnetron sputtering at room temperature by regulating the substrate bias voltage (V s) in a wide range (0 ~ -184 V). The effect of V s on the performance of a-GaO x films and their photodetector devices, such as the chemical composition, optical, morphological, and electrical properties, are systematically investigated. It's found that both the refractive index and the film relative mass density are highly dependent on the Ga/O ratio that can be effectively modified by the V s. And the subband trap density or/and microvoid defects in a-GaO x films can be largely reduced under a well-selected V s. The deep-ultraviolet photodetectors based on the optimized a-GaO x thin films show a responsivity of nearly 13 A/W with an ultrahigh UV/vis. rejection ratio. The research suggests that substrate bias voltage may be a feasibly subsidiary method for low-temperature magnetron sputtering technology with respect to the quality control of a-GaO x films. [ABSTRACT FROM AUTHOR]

P-type Cu-Sn-I thin films with different Sn contents (CSn) were fabricated in air via a simple and low-cost spin-coating method. Sn additive facilitates the amorphization of CuI, and a complete amorphous phase of Cu-Sn-I film is achieved at CSn =15%. With increasing CSn, the optical bandgap increases and refractive index decreases, probably due to the influence of Sn-additive on both the electronic structure and phase state of the films. The air-processed Sn-free CuI films show p-type conduction with hole mobility and a concentration of 17.3 cm2/V−1 s−1 and 1.1 × 1019 cm−3, and an increasing trend of resistivity is observed along with a large drop in hole concentration during the Sn-inspired amorphization process. Moreover, transparent Cu-Sn-I/IGZO p–n junctions were constructed, exhibiting the optimum rectifying characteristic at CSn = 15% with a forward-to-reverse ratio of 6.2 × 103. [ABSTRACT FROM AUTHOR]

Background: The brain's dynamic spontaneous neural activity and dynamic functional connectivity (dFC) are both important in supporting cognition, but how these two types of brain dynamics evolve and co-evolve in subjective cognitive decline (SCD) and mild cognitive impairment (MCI) remain unclear. The aim of the present study was to investigate recurrent and concurrent patterns of two types of dynamic brain states correlated with cognitive decline. Methods: The present study analyzed resting-state functional magnetic resonance imaging data from 62 SCD patients, 75 MCI patients, and 70 healthy controls (HCs). We used the sliding-window and clustering method to identify two types of recurrent brain states from both dFC and dynamic regional spontaneous activity, as measured by dynamic fractional amplitude of low-frequency fluctuations (dfALFF). Then, the occurrence frequency of a dFC or dfALFF state and the co-occurrence frequency of a pair of dFC and dfALFF states among all time points are extracted for each participant to describe their dynamics brain patterns. Results: We identified a few recurrent states of dfALFF and dFC and further ascertained the co-occurrent patterns of these two types of dynamic brain states (i.e., dfALFF and dFC states). Importantly, the occurrence frequency of a default-mode network (DMN)-dominated dFC state was significantly different between HCs and SCD patients, and the co-occurrence frequencies of a DMN-dominated dFC state and a DMN-dominated dfALFF state were also significantly different between SCD and MCI patients. These two dynamic features were both significantly positively correlated with Mini-Mental State Examination scores. Conclusion: Our findings revealed novel fMRI-based neural signatures of cognitive decline from recurrent and concurrent patterns of dfALFF and dFC, providing strong evidence supporting SCD as the transition phase between normal aging and MCI. This finding holds potential to differentiate SCD patients from HCs via both dFC and dfALFF as objective neuroimaging biomarkers, which may aid in the early diagnosis and intervention of Alzheimer's disease. [ABSTRACT FROM AUTHOR]

Amorphous Ga2O3:CdO thin films and their thin-film transistor (TFT) photodetectors were fabricated via a simple and low-cost spin-coating method. The film optical bandgap and TFT electrical parameters can be effectively regulated via changing the Cd content. The optimized Ga2O3:CdO TFT photodetector exhibited a responsivity of 2.17 A/W and a high UV/vis. rejection of 1.88 × 104 under 260 nm at small working biases, which are comparable or even superior to the recently reported results. Systematic comparison between metal-semiconductor-metal- and TFT-type photodetectors further confirmed that our TFT photodetectors had superior detective performance and lower electrical power consumption. [ABSTRACT FROM AUTHOR]

Dielectrics fabrication on rough substrates, always leading to microstructural defects and detrimental dielectric properties eventually, is a great challenge for academic endeavors in this field. We report here on self-flattening AlO x :Y dielectric thin films processed by a facile aqueous solution method. The obtained AlO x :Y dielectrics are dense, large-area uniform, and amenable to accurate control of film thickness by repeating the deposition cycles. In particular, an atomically smooth surface with a RMS of 0.10 nm was realized for the AlO x :Y film with a thickness of 14.5 nm on Si wafer, yielding a low leakage current density of 7.9 × 10-8 A cm-2@2 MV/cm, a dielectric constant of 8.8 @100 Hz, and an attenuated dielectric dispersion property. The interactions between pre-baked YO x underlayer and later-dropped AlO x precursor were comprehensively investigated, in order to understand the film growth mechanism and the origin of self-flattening effect. Fortunately, this self-flattening effect is also applicable to other substrates. A RMS of 0.81 nm was achieved on ITO glasses, and the height distribution profile of the film surface was found to follow symmetric Gaussian distribution. This preparation routine was also examined by device verification in the fully-transparent thin-film transistors. The combination of ease of preparation and attractive physical properties would provide a green-route solution platform for dielectric synthesis, for interface engineering, and for well-performed devices on rough substrates. [ABSTRACT FROM AUTHOR]

Chitosan (CS) dielectrics are in favor of packed CuI films with tiny grains on them under a robust ambient conditions, and hence facilitate transparent and flexible p-type CuI thin-film transistors with high mobility and on/off current ratio. Complementary inverters based on the CuI transistors demonstrate a voltage gain over 20. [Display omitted] • Flexible/transparent p-Type CuI TFTs are constructed, with μ FE up to 65 cm2V−1s−1 and I on / I off of 104. • Chitosan dielectrics facilitate easy coating of high-quality CuI films under permissive conditions. • Complementary inverters are demonstrated by combining p-type CuI and n -type ITO TFTs. High-performance transparent and low-process-temperature p-type devices are essential for portable and 'invisible' electronics. In this work, high-performance p-channel copper iodide (CuI) thin-film transistors (TFTs) with a bottom-gate structure are achieved via replacing traditional SiO 2 dielectric with Chitosan (CS, a kind of solid polymer electrolytes), with the threshold voltage down to −0.35 V, field-effect mobility (μ FE) up to 60 cm2V−1s−1 and on/off current ratio (I on / I off) beyond 103. The CuI films spin-coated on CS-dielectrics in the air with high humidity have smoother surface morphology, tinier grains, higher packing density and hence a higher μ FE , in sharp contrast with the SiO 2 case. In addition, the CuI films on CS-dielectrics demonstrate a work function ∼ 0.1 eV lower than that on SiO 2 , which implies a smaller hole concentration and higher I on / I off. And the low process temperature (<50 °C) facilitates the achievement of flexible and transparent CuI TFTs with μ FE and I on / I off comparable to those on rigid InSnO (ITO) glass. Furthermore, complementary inverters composed of p-type CuI and n -type ITO TFTs are demonstrated with clear inverting characteristics and voltage gain of over 20. [ABSTRACT FROM AUTHOR]

The anisotropic carrier trapping behaviors was demonstrated for ambipolar tin monoxide (SnO) thin-film transistors (TFTs). On one hand, the TFTs exhibited good stability with almost no changes in transfer characteristics under negative gate-bias stress (NGBS). On the other, under positive gate-bias stress (PGBS), the transfer curves presented parallel and positive shift with no degradation in field-effect mobility and subthreshold voltage swing. The stress-time evolution of the turn-on voltage shift, induced by different positive stress voltages and temperatures, could be described by the stretched exponential model. The relaxation time was extracted to be 1.6 × 10 4 s at room temperature with activation energy of 0.43 eV, indicating that the ambipolar SnO TFTs under PGBS approach the stability of amorphous indium-gallium-zinc oxide based TFTs. [ABSTRACT FROM AUTHOR]

In this work, nitrogen‐doped zinc‐tin‐oxygen (ZnSnO:N) optoelectronic synaptic thin film transistors (TFTs) with superior visible light response are fabricated. Nitrogen doping narrows the bandgap of ZnSnO, which in turn broadens the absorption spectrum. Additionally, the reduction of non‐radiative centers in the channel layer prolongs the lifetime of the photogenerated electrons, resulting in enhancements to the photo response throughout the visible region. Optoelectronic synaptic devices based on ZnSnO:N TFTs can accurately replicate synaptic behaviors, including short‐term plasticity (STP) and long‐term plasticity (LTP). Furthermore, the ZnSnO:N optoelectronic synaptic TFT‐based array has the potential to improve image contrast. The ZnSnO:N TFT exhibits a considerable improvement in both visible light photosensitivity and synaptic plasticity. [ABSTRACT FROM AUTHOR]

The pathophysiology of coronasomnia remains unclear. This study aimed to investigate changes in white matter (WM) microstructure and inflammatory factors in patients with sleep disorders (SD) characterized by poor sleep quantity, quality, or timing following coronavirus disease 2019 (COVID-19) infection in the acute phase (within one month) and whether these changes could be recovered at 3-month follow-up. 29 acute COVID-19 patients with SD (COVID_SD) and 27 acute COVID-19 patients without SD (COVID_NonSD) underwent diffusion tensor imaging (DTI), tested peripheral blood inflammatory cytokines level, and measured Pittsburgh Sleep Quality Index (PSQI), and matched 30 uninfected healthy controls. Analyzed WM abnormalities between groups in acute phase and explored its changes in COVID_SD at 3-month follow-up by using tract-based spatial statistics (TBSS). Correlations between DTI and clinical data were examined using Spearman partial correlation analysis. Both COVID_SD and COVID_NonSD exhibited widespread WM microstructure abnormalities. The COVID_SD group showed specific WM microstructure changes in right inferior fronto-occipital fasciculus (IFOF) (lower fractional anisotropy [FA]/axial diffusivity [AD] and higher radial diffusivity [RD]) and left corticospinal tract (CST) (higher FA and lower RD) and higher interleukin-1β (IL-1β) compared with COVID_NonSD group. These WM abnormalities and IL-1β levels were correlated PSQI score. After 3 months, the IFOF integrity and IL-1β levels tended to return to normal accompanied by symptom improvement in the COVID_SD relative to baseline. Abnormalities in right IFOF and left CST and elevated IL-1β levels were important neurophenotypes correlated with COVID_SD, which might provide new insights into the pathogenesis of neuroinflammation in SD patients induced by COVID-19. • TBSS identified the specific WM changes in right IFOF and left CST at acute phase COVID-19 patients with SD. • Higher IL-1β level was identified in the acute COVID-19 patients with SD. • The right IFOF and IL-1β level tended to return to normal accompanied by sleep symptoms improvement after 3 months in the acute COVID-19 patients with SD. [ABSTRACT FROM AUTHOR]

The exploration of bionic neuromorphic chips, capable of processing sensory data in a human‐like manner, is both a trend and a challenge. There is a strong demand for phototransistors that offer broadband in‐sensor adaptability. This study introduces a bioinspired vision sensor based on InP quantum dots (QDs)/InSnZnO hybrid phototransistors. This novel design combines the excellent electrical transportation features of oxide semiconductors with the superior optoelectronic response of InP QDs. The resulting hybrid devices exhibit exceptional gate controllability and a robust visible‐light response. These characteristics enable the emulation of multiple functions of the human visual system and the accommodation of varying light intensity environments. Furthermore, the phototransistor array successfully replicates the scotopic and photopic adaptation recognition behaviors of the human retina. Notably, the device demonstrates faultless competency in image processing, achieving an impressive 93% accuracy for digit recognition. These findings contribute to the advancement of bionic neuromorphic chips and offer promising opportunities for future developments in the bioinspired visual system. [ABSTRACT FROM AUTHOR]

Optoelectronic synapse, well coupling the optical and electrical signals in one device, is an important building block in neuromorphic hardware library. Herein, optoelectronic synaptic devices are demonstrated based on a unique amorphous oxide semiconductor (InGaCdO [IGCO]) that can be spiked by broadband light signals from ultraviolet to near‐infrared region, approaching the wavelength of 1000 nm. These optically stimulated synaptic devices are based on the conventional bottom‐gate thin‐film transistor (TFT) configuration, providing the beneficial process/structural compatibility with the flat‐panel display industry. The IGCO TFTs, showing an ultrahigh field‐effect mobility up to 106 cm2 V−1 s−1, can well simulate a series of basic synaptic functionalities via changing the pulse intensity, number, and frequency. The device plasticity originates from the dynamic ionization and neutralization of oxygen vacancy‐related defects. Also, the mechanism underlying this dynamic process is discussed in detail, verifying that oxygen vacancy can turn to its ionized state by directly absorbing a photon having enough energy or with the aid of holes. The relatively higher carrier mobility, smaller bandgap, and larger activation energy of oxygen vacancy for the IGCO together facilitate the achievement of broadband optoelectronic synaptic devices. [ABSTRACT FROM AUTHOR]

Separative extended-gate AlGaAs/GaAs high electron mobility transistor (HEMT) biosensors based on the capacitance change strategy are proposed and fabricated. The working mechanism underlying this strategy is clearly clarified via examining the capacitance evolution on biorecognition and the capacitance matching issue between the HEMT and the sensing pad. The fabricated biosensors demonstrate a good linear current/voltage response to a label-free prostate-specific antigen (PSA) target over a broad concentration range of 100 fg/ml to 10 ng/ml in both 0.1× and 1× phosphate buffered saline solutions. Specifically, the sensitivity variation approaches 8.7% dec−1 at the critical concentration level of 2–8 ng/ml that enters the normal PSA region in the human body. The advantages of high sensitivity, low-cost, and convenience of usage make the proposed HEMT biosensors potential candidates for prostate cancer diagnosis. [ABSTRACT FROM AUTHOR]

Today, the earnest need for earth-abundant and environmentally friendly thermoelectric materials has revealed the importance of semiconductor metal oxides in order to eliminate the barrier towards their wide-ranging use in industrial applications. In the present work, we demonstrate the synthesis of p-type tin oxide thin films on quartz glass and Si substrates by using electron beam evaporation technique followed by rapid thermal annealing process at 200 °C for 20 min in Ar-atmosphere. Annealing-induced structural, electrical, optical and thermoelectric properties of pristine and annealed SnO thin films are primarily studied. The compositional and structural analysis of SnO films are performed by using X-Ray Diffraction, Scanning Electron Microscope as well as Atomic Force Microscope. Moreover, the mechanism of thermoelectric transportation at different measurement temperatures is deeply inspected via thermoelectric measurements. The Seebeck coefficient, carrier concentration and hole mobility in conjunction with the development of thin film nanostructures are discussed, predominantly. The optimal annealing may tune structural, electro-optic and thermoelectric properties of SnO films for the commercial-level maturity of thermoelectric devices for energy applications. • Synthesis of high quality p-type SnO thin films by e-beam evaporation method. • Phase stability can be achieved by optimal annealing of tin oxide thin films. • Electrical resistivity and mobility affects the thermoelectric properties. • Optimal annealing reduces the crystal imperfections and band-tail states in SnO films. • The air-annealing induces the phase transition in SnO x thin films. [ABSTRACT FROM AUTHOR]

Plasmonic structural colors, arising from resonance interactions between photons and metallic nanostructures, have been developed rapidly for high‐end applications. However, common structural color materials and fabrication methods usually have open plasmonic nanostructures and limited scalability, respectively. Here, a new scheme based on Ag nanowire arrays/SiO2 composite metamaterial films with subwavelength enclosed nanostructures involved that combine a dielectric gap layer and a metal mirror is presented. The whole stacked structure can be simply prepared only via magnetron sputtering without any other procedures. Specifically, by changing deposition parameters, the geometry size and sub‐10 nm periodic parameters of the structure unit cell array can be finely tuned in a controllable and reproducible way. By experiments and simulations, it is demonstrated how interwire coupled plasmonic transverse modes in vertically orientated nanocavity arrays control multiple nanocavity standing‐wave resonances at visible wavelengths, generating three primary colors‐included bright and saturated colors across a wide gamut. Large‐area and uniform structural colors, whether on rigid or flexible substrates, show angle‐insensitive and air‐stable features. In a wider perspective, this work suggests that the material scheme and fabrication advances represent a robust platform for plasmonic color designing, theory exploring, and large‐scale manufacturing. [ABSTRACT FROM AUTHOR]

Thin-film transistors (TFTs) with ScInO or MgScInO semiconductors were fabricated with the annealing temperature of only 150 °C. Compared with ScInO TFT, MgScInO TFT exhibited much better stability under negative-bias temperature stress (NBTS) at 60 °C with negative turn-on voltage (${V}_{ \mathrm{\scriptscriptstyle ON}}$) shift of −0.6 V at the initial stress stage (≤;900 s) and then positive $V_{ \mathrm{\scriptscriptstyle ON}}$ shift (>900 s). First-principles calculations show that the oxygen vacancies (${V}_{\text {O}}$) tend to be bounded with Mg and form Mg– ${V}_{\text {O}}$ pairs with activating (or binding) energy of greater than 0.1369 eV, which is ascribed to the NBTS stability improvement for MgScInO TFT. [ABSTRACT FROM AUTHOR]

Concerning the revolutionary future of electronic devices, high-performance solution-processable semiconductors have earned increasing academic and industrial research interests. In this paper, we synthesize In-Ga-Cd-O semiconductor thin films via a solution method. Transparent amorphous/nanocrystalline oxide thin films with small surface roughness have been grown by controlling the relative ratio of Cd-content. The present thin-film transistor with an optimized Cd-ratio exhibits a saturation field-effect mobility up to 10 cm² V-1 s-1, an on/off current ratio of ≈1.3×109, and a threshold voltage shift of ≈2.6 V under -5 V gate bias of 10 000 s, which are superior or comparable to those reported values of solution-processed conventional In-Ga-Zn-O counterparts. Our results indicate that the proposed In-Ga-Cd-O semiconductor would endow a promising transparent amorphous/nanocrystalline active material for electronic devices. [ABSTRACT FROM AUTHOR]

In this article, we report the growth of zinc‐tin nitride (ZnSnN2) thin films as a potential absorber for photovoltaic applications by fabricating a heterojunction of n‐ZnSnN2/p‐SnO. The performance of the heterojunction has been monitored through selective deposition of top electrode with different materials (Ni/Au or Al). The electron‐transfer process from the ZnSnN2 layer to the cathode is facilitated by selecting metal electrode with relatively low work function, which also boosts up the electron injection or/and extraction. The diode exhibits a good J–V response in the dark with a rectification ratio of 3 × 103 at 1.0 V and an ideality factor of 4.2 in particular with Al as the top electrode. Under illumination, the heterostructure solar cell demonstrates a power conversion efficiency of ≈0.37% with an open circuit voltage of 0.25 V and a short circuit current density of 4.16 mA cm−2. The prime strategies, on how to improve solar cell efficiency concerning band offsets and band alignment engineering are also discussed. [ABSTRACT FROM AUTHOR]

Background: Premenstrual syndrome (PMS) is becoming highly prevalent among female and is characterized by emotional, physical and behavior symptoms. Previous evidence suggested functional dysregulation of female brain was expected to be involved in the etiology of PMS. The aim of present study was to evaluate the alterations of spontaneous brain activity in PMS patients based on functional magnetic resonance imaging (fMRI).Methods: 20 PMS patients and 21 healthy controls underwent resting-state fMRI scanning during luteal phase. All participants were asked to complete a prospective daily record of severity of problems (DRSP) questionnaire.Results: Compared with healthy controls, the results showed that PMS patients had increased fALFF in bilateral precuneus, left hippocampus and left inferior temporal cortex, and decreased fALFF in bilateral anterior cingulate cortex (ACC) and cerebellum at luteal phase. Moreover, the DRSP scores of PMS patients were negatively correlated with the mean fALFF in ACC and positively correlated with the fALFF in precuneus.Limitations: (1) the study did not investigate whether or not abnormal brain activity differences between groups in mid-follicular phase, and within-group changes. between phases.(2) it was relatively limited sample size and the participants were young; (3) fALFF could not provide us with more holistic information of brain network;(4) the comparisons of PMS and premenstrual dysphoric disorder (PMDD) were not involved in the study.Conclusions: The present study shows abnormal spontaneous brain activity in PMS patients revealed by fALFF, which could provide neuroimaging evidence to further improve our understanding of the underlying neural mechanism of PMS. [ABSTRACT FROM AUTHOR]

Fully transparent InZnO thin-film transistors (TFTs), with either a bottom gate or an in-plane gate device structure, were fabricated using the solution-processed SA proton conducting films as gate dielectrics. The self-assembled InZnO channel with different thickness by the gradient shadow mask was fabricated during the same batch radio-frequency magnetron sputtering. The threshold voltage can be modulated from −0.25 to +0.12 V and from −0.07 to +0.25 V by the channel layer thickness variations for the vertically-coupled and laterally-coupled InZnO TFTs, respectively. Accordingly, these InZnO TFTs can operate in either depletion or enhancement mode on the same chip. A general expression of the turn-on voltage in relation to the channel thickness is derived. The device performance with an on/off current ratio of ≥1.5 × 106, a subthreshold swing of down to 70 mV/decade, and a field-effect mobility of up to 34.3 cm2/V · s is exhibited. Our results demonstrate that the same batch channel processing is potentially applied in logic circuits or functional electronics. [ABSTRACT FROM AUTHOR]

We report a facile and low-temperature aqueous route for the fabrication of various oxide thin films (Al 2 O 3 , In 2 O 3 and InZnO). A detail study is carried out to reveal the formation and properties of these sol-gel-derived thin films. The results show that the water-based oxide thin films undergo the decomposition of nitrate group as well as conversion of metal hydroxides to form metal oxide framework. High quality oxide thin film could be achieved at low temperature by this aqueous route. Furthermore, these oxide thin films are integrated to form thin-film transistors (TFTs) and the electrical performance is systematically studied. In particular, we successfully demonstrate In 2 O 3 /Al 2 O 3 TFTs with high mobility of 30.88 cm 2 V −1 s −1 and low operation voltage of 4 V at a maximum processing temperature of 250 °C. [ABSTRACT FROM AUTHOR]

The solution-processed sodium-alginate (SA) films, with nanoporous/nanochannel microstructure, possess a total absorbed water number of 10420 ± 395 molecules per square nanometer, which gives rise to a high proton conductivity of 4.0 × 10−4 S cm−1. When SA films used as gate dielectric in the thin film transistors, electric-double-layer (EDL) would be formed whether at the dielectric/channel or at dielectric/gate electrode interface, leading to a huge specific capacitance and low operating voltage for the TFTs. More importantly, due to the three-dimensional proton conducting characteristic, one can design the TFT device structure expediently from conventional vertical gate coupling to laterally coplanar gate coupling structure. The TFTs with ease-design device layout have potential applications in multifunctional electronic devices. [ABSTRACT FROM AUTHOR]

Purpose: We sought to evaluate the performance of a new "one-stop-shop" scan protocol combining brain computed tomography perfusion (CTP) and head-and-neck CT angiography (CTA) imaging for acute stroke patients using a 256-detector CT scanner.Method: From March to August 2020, 60 patients (30 men and 30 women) aged 22-88 years with suspected acute stroke were enrolled and randomly divided into 2 groups to undergo brain CTP and head-and-neck CTA with a 256-detector CT system. Group A used traditional scan protocol with a separate brain CTP and head-and-neck CT examination that included non-contrast-enhanced and contrast-enhanced acquisitions; group B used the new "one-stop-shop" scan protocol with head-and-neck CTA data inserted into brain CTP scans at the peak time (PT) of the arterial phase. The insertion point of the head-and-neck CTA data was determined by a test bolus. The examination time, contrast dose, radiation dose, and image quality were compared between the groups.Results: The total contrast dose was reduced by 40% in group B compared to group A (60 mL vs. 100 mL). The imaging time was 52.5 ± 2.6 s in group B and 74.9 ± 3.3 s in group A, showing a reduction of approximately 43% in group B. There was no significant difference in image quality both quantitatively and qualitatively between the groups (all P > 0.05). Group B had a slight reduction in dose length product (1139.0 ± 45.3 vs. 1211.6 ± 31.9 mGy·cm, P < 0.001).Conclusions: The proposed "one-stop-shop" scan protocol combining brain CTP and head-and-neck CTA on a 256-detector CT system can reduce imaging time and contrast dose, without affecting image quality or perfusion results, compared to the traditional protocol of separating the examinations. [ABSTRACT FROM AUTHOR]

[Display omitted] • Synthesis of high quality p-type SnO thin films by e-beam evaporation method. • Post deposition heat treatment of SnO x films at temperature (300–700 °C). • Optimal annealing reduces the crystal imperfections and band-tail states in SnO films. • Study of temperature-dependent morphology evolution for preferred crystal growth. In the present work, we demonstrate the growth of tin oxide (SnO x) thin films using electron beam evaporation method to study the phase transition from stannous oxide (SnO) to stannic oxide (SnO 2) by varying annealing temperature (i.e., from 300 to 700 °C). Annealing induced morphology evolution and structural modifications stimulate the process of phase-transformation, which is primarily discussed by divided the entire temperature range into two-regimes. Regime-A (from 300 to 400 °C) consists of tetragonal α-SnO dominated phase, regime-B (from 600 to 700 °C) exhibits orthorhombic pure SnO 2 phase. However, these regimes are being separated by an interface conferring a mixed-phase of tin oxides at an annealing temperature ∼500 °C. This temperature-dependent phase-inversion is adequately controlled by tuning the morphological, structural and optical properties of SnO x thin films to develop homo/heterostructures for various photovoltaic and optoelectronic applications. [ABSTRACT FROM AUTHOR]

Abstract: An amorphous carbon thin film, with through-pores of several tens of nanometers in size, has been synthesized by annealing magnetron sputtered nitrogen-doped carbon thin films at elevated temperature in an inert atmosphere. Based on this nanoporous carbon film, we first report forming-free resistive switching in a two terminal device containing ready-made metal nanofilaments. Such nanoporous carbon-based resistance memory device shows low operation voltages and good endurance and retention performance. [Copyright &y& Elsevier]

• The stability and sensitivity of FET biosensors are improved via decorating the Au sensing pads with T-ZnO. • T-ZnO helps construct a 3D and concave detection front with many biological modification sites and small Debye volume. • T-ZnO helps improve long-term air stability/test repeatability in bio-solution by releasing the stress and erosion effect. • Biosensors with a chemical bio-functionalized T-ZnO front show a wide detection scope, good sensitivity and stability. [Display omitted] In this study, separative extended-gate AlGaAs/GaAs high electron mobility transistor (HEMT) biosensor is proposed for prostate-specific antigen (PSA) detection. Zinc oxide nanotetrapods (T-ZnO) with a four-leg structure is introduced onto the sensing pad to form a three-dimensional (3D) and concave detection front. Compared with common plane front, the elaborately-designed-3D and concave detection front can offer more biological modification sites and decrease the Debye volume, resultantly improving both the detection scope and sensitivity. Anti-PSA probes can be fixed at any sites of T-ZnO via a chemical bio-functionalization method, which facilitates better detection performance by comparison with a physical modification scheme. On the other hand, the T-ZnO nanostructures with the four-leg configuration are capable of releasing the stress and erosion effect of the solution on the plane Au film, contributing to a great improvement in the reliability of the biosensors. The optimized biosensors with chemical bio-functionalized T-ZnO detection front demonstrate good linear current/voltage response to label-free PSA target in the concentration range from 5 fg/ml~5 ng/ml and a sensitivity variation ~ 1.3% dec−1. [ABSTRACT FROM AUTHOR]

[Display omitted] • The abnormal local and long-range FCD in MCI compared with HCs. • The reversed FCD was found in MCI after treatments of acupoint-related moxibustion. • After moxibustion treatment, the MoCA scores of MCI were improved. Mild cognitive impairment (MCI) is a general neurodegenerative disease. Moxibustion has been shown to have remarkable effect on cognitive improvement, however, less is known about the effect of moxibustion on MCI and its underlying neural mechanism. This study aimed to investigate the ameliorative brain network in MCI after treatments of acupoint-related moxibustion. Resting-state functional MRI were derived from 47 MCI patients and 30 healthy controls (HCs). Patients were randomized as Tiaoshen YiZhi (TSYZ, n = 27) and sham (SHAM, n = 20) acupoint moxibustion groups. Functional connectivity density (FCD) method and repeated-measures two-way analysis of variance (ANOVA) were performed to ascertain the interaction effects between groups (TSYZ and SHAM) and time (baseline and post-treatment). Abnormal FCD was examined between baseline and post-treatment in TSYZ and SHAM groups, respectively. Compared with HCs, MCI showed altered FCD in the middle frontal cortex (MFC), inferior frontal cortex, temporal pole, thalamus and middle cingulate cortex. After moxibustion treatment in MCI, 1) a significant time-by-groups interaction was observed in the medial prefrontal cortex (mPFC); 2) abnormal long-range FCD (lrFCD) in the mPFC and MFC were modulated in TSYZ group; 3) significantly improved clinical symptoms; 4) changed lrFCD in the MFC was significantly negatively correlated with the increased Montreal Cognitive Assessment scores in TSYZ group. These imaging findings suggest that treatments of acupoint-related moxibustion could improve lrFCD in certain regions related to self-related cognitive and decision making. Our study might promote understanding of MCI neural mechanisms and expand the clinical application of moxibustion in MCI. [ABSTRACT FROM AUTHOR]

While the dry prelithiation method has been extensively applied in WO 3 -based electrochromic devices, the insight of prelithiated WO 3 films is still ambiguous. Herein, the electrochromic and electrochemical performance of the WO 3 films prepared by an in situ dry prelithiation method is investigated. The deposited lithium is calculated to be separated into 47.8% 'active lithium' and 52.2% 'dead lithium'. On one hand, the enhancement of the electrochemical cycling stability and charge density can be ascribed to the preactivation of 'active lithium', which enlarges the surface area for ion transporting. On the other, the irreversible formation of 'dead lithium zone' in the prelithiated WO 3 films originates from 'dead lithium seed', leading to the detriment of optical properties. This work further provides a profound insight into the implication of prelithiated lithium on the electrochemical and electrochromic properties of the WO 3 films. • The prelithiated WO 3 films were prepared by an in situ dry prelithiation method. • Mechanistic insight into the prelithiated WO 3 films in the electrochromic device is clarified. • A complementary electrochromic device with a superior cycling stability over 10,000 cycles is assembled. [ABSTRACT FROM AUTHOR]

• An new multi-task learning framework is devised for differential diagnosis of subjective cognitive decline and mild cognive impairment. • The proposed multi-task learning algorithm combines functional and structural brain information. • The proposed method can discover the most disease-related brain regions and their connectivity. • The extensive experiments demonstrate good classification performance against competing techniques. Early diagnosis and intervention of mild cognitive impairment (MCI) and its early stage (i.e., subjective cognitive decline (SCD)) is able to delay or reverse the disease progression. However, discrimination between SCD, MCI and healthy subjects accurately remains challenging. This paper proposes an auto-weighted centralised multi-task (AWCMT) learning framework for differential diagnosis of SCD and MCI. AWCMT is based on structural and functional connectivity information inferred from magnetic resonance imaging (MRI). To be specific, we devise a novel multi-task learning algorithm to combine neuroimaging functional and structural connective information. We construct a functional brain network through a sparse and low-rank machine learning method, and also a structural brain network via fibre bundle tracking. Those two networks are constructed separately and independently. Multi-task learning is then used to identify features integration of functional and structural connectivity. Hence, we can learn each task's significance automatically in a balanced way. By combining the functional and structural information, the most informative features of SCD and MCI are obtained for diagnosis. The extensive experiments on the public and self-collected datasets demonstrate that the proposed algorithm obtains better performance in classifying SCD, MCI and healthy people than traditional algorithms. The newly proposed method has good interpretability as it is able to discover the most disease-related brain regions and their connectivity. The results agree well with current clinical findings and provide new insights into early AD detection based on the multi-modal neuroimaging technique. [Display omitted] [ABSTRACT FROM AUTHOR]

The block copolymer (BCP) templates with nanoscale structures and diverse morphologies have attracted much attention for nanofabrication in photonic and plasmonic research fields. Herein, PS-b-PMMA BCP nanotemplates with different morphologies, including the patterns of hexagonal hole arrays, fingerprint stripes, and their mixture, are successfully prepared for in-depth microstructural and optical characterizations. Apart from direct microstructure observations and component characterization, ellipsometric measurements are mainly applied to characterize structural and optical evolution of these BCP nanotemplates undergoing different preparation stages. Interestingly, among different BCP nanotemplates, two typical reflectance peaks in the ultraviolet region (200–250 nm) are distinctly different from each other, due to their PS- and thickness-dependent optical behaviors. With the preparation proceeding, there are synchronous diminution in the intensity of the two peaks, accompanying with an obvious blue-shift for the shorter wavelength peak. In addition, the variation of refractive index and ellipsometric parameters greatly demonstrates morphology-dependent optical behaviors among different BCP nanotemplates. Finally, Au-covered BCP nanotemplates present the distinct template-morphology-dependent visible-light responses, demonstrating different light-matter interactions occurred in their plasmonic Au nanostructures. • The structural and optical features of BCP templates were in-depth studied. • The optical changes of BCP templates with different treatments were investigated. • Ellipsometry was used to discern the morphological discrepancy of BCP templates. [ABSTRACT FROM AUTHOR]

A solar selective absorber coating of CrN x O y /SiO2 was prepared on Cu (Si) substrate using DC reactive magnetron sputtering technique. The coating exhibits a high absorptivity (α) of 0.947 and a low emissivity (ε) of 0.05 at 80°C. The spectral selectivity (α/ε) of the coating on Cu substrate is stable (0.930/0.073) even after heat-treatment at 278°C in air for 300h, but decreased (0.904/0.135) at 278°C for 600h. The determinants to govern the thermal stability were investigated by micro-Raman spectroscopy, X-ray photoelectron spectroscopy (XPS) and Auger electron spectroscopy (AES) measurements, which reveal that the element diffusion whether throughout all the stacked layers or near the interface region, the chemical interactions adjacent to the interface, and the interface width broadening are the Achilles' heel for the solar thermal coatings to sustain high thermal stability. [ABSTRACT FROM AUTHOR]

InZnO thin-film transistors using high-κ Ta2O5 gate dielectric are presented and analysed. The large capacitance coupling effect of amorphous Ta2O5 results in fabricated devices with good electrical properties. However, an anomalous negative threshold voltage (Vth) shift under positive bias stress is observed. It is suggested that electron detrapping from the high-κ Ta2O5 dielectric to the gate electrode is responsible for this Vth shift, which is supported both by the logarithmical dependence of the Vth change on the duration of the bias stress and device simulation extracted trapped charges involved. [ABSTRACT FROM AUTHOR]

Lithium-ion migration at the WO 3 /electrolyte interface is governed by the phase transformation mechanism by which metastable states are replaced from one phase to another. Herein, an in situ single nanowire-based cell is constructed to investigate the dynamic phase transformation and morphology evolution of h-WO 3 nanowire in real-time during its deep lithiation. One of the most significant features of h-WO 3 lithiation is the irreversible transformation from h-WO 3 to Li 2 WO 4. There are a large number of deep ion-trapping sites composed of 4 O atoms in Li 2 WO 4 crystal structure, that is, inserted lithium ions are irreversibly bound in these traps and nearly cannot be deintercalated. A mechanism on irreversible WO 3 -to-Li 2 WO 4 transformation in deep lithiation reaction is demonstrated. With the aid of in situ transmission electron microscopy, we controllably triggered lithium-ion migration at the WO 3 /electrolyte interface and directly visualized the nanoscale lithium-ion migration as a stop motion movie. Hexagonal WO 3 irreversible transformation to Li 2 WO 4 can be experimentally demonstrated via in situ HRTEM in the deep lithiation process including the initial activation of the lithium metal, the wetting of a single WO 3 nanowire and the migration of lithium ions into WO 3 , and the restructuring of hexagonal WO 3. [Display omitted] [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

• Long-term-stable WO 3 -PB complementary electrochromic devices were constructed. • The long-term stability and high optical modulation of electrochromic devices are exhibited. • Electrochemical refinement analysis of WO 3 and PB electrodes is performed. • The synergistic effects of Li+ and H+ on WO 3 and PB electrodes are clarified. The complementary electrochromic devices based on WO 3 and Prussian blue electrodes (PB) have shown a limited chemical stability and durability because WO 3 is degraded in electrochromic performance and PB is gradually dissolved in the Li+-based electrolyte under neutral pH conditions. Herein, the utilization of acetic acid as super-additive solution was proposed to improve WO 3 cathodes and stabilize PB anodes, in which the highly nanoporous nanocrystal-in-glass WO 3 and hierarchical PB was made by electron beam evaporation and electrochemical deposition method, respectively. Our findings suggest that synergistic effects of Li+ and H+ on WO 3 and Prussian blue electrodes contribute to the improvement on electrochemical, electrochromic, and cycling stability performance of the whole device. Impressively, the WO 3 -PB complementary electrochromic device could experience a superior long-term cycling stability of over 10,000 cycles, with a high coloration efficiency of 137.80 cm2 C−1 and a maximum transmittance modulation of 66.22%@ 633 nm. All these results open a new way to the construction of high-performance electrochromic devices. [ABSTRACT FROM AUTHOR]