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The table-like magnetocaloric effect is significant for the magnetic refrigeration applications above 20 K based on the Ericsson cycle. Herein, we prepared a series of Nd6Fe13Pd1–xCux (x=0.05, 0.1, 0.15) compounds by the arc-melting method. These compounds show the single crystalline phase in the tetragonal Nd6Fe13Si-type structure with the space group I4/mcm. A magnetic phase transition from ferromagnetism to antiferromagnetism and a metamagnetic transition from the antiferromagnetic state to the ferromagnetic state were observed in each of the compounds. The compounds exhibit table-like magnetocaloric effects with large refrigerant capacities. A constant ΔSM in a temperature span of 40 K in the Nd6Fe13Pd0.85Cu0.15 compound was observed. For a field change of 0–5 T, the peak values of –ΔSM for the Nd6Fe13Pd0.95Cu0.05, Nd6Fe13Pd0.90Cu0.10, and Nd6Fe13Pd0.85Cu0.15 compounds were estimated to be 4.8, 4.6 and 4.4 J/(kg·K) with corresponding refrigerant capacity values of 323, 331 and 316 J/kg, respectively. The obtained table-like magnetocaloric effects with large refrigerant capacities as well as fairly small thermal and magnetic hysteresis deem these series of compounds good candidates for single-phase magnetic refrigeration based on the Ericsson cycle.

The photocatalytic water splitting has a stupendous role to generate renewable hydrogen. However, the overall water splitting reaction is limited by the sluggish oxidation step. Bismuth vanadate (BiVO4) has been identified as one of the most promising n-type semiconductors for photocatalytic water oxidation due to its small energy gap and favorable band alignment. Thus, it is necessary to summarize the recent progress done on BiVO4 for the guidance of future research. In this review, we have discussed recent strategies that have been adopted to boost its photoconversion efficiency at three different levels: (1) facet control, (2) morphological control and, (3) interfacial control. The roles of high indexed facets, anisotropic morphologies, and mediator-based Z schemes are comprehensively discussed and the emphasis is given to find the suitable structural, morphological, and interfacial combination of BiVO4 for efficient water oxidation.

Amorphous gallium tin oxide (GTO) thin films were prepared by a facile, and eco-friendly, aqueous solution process and their applications in thin-film transistors (TFTs) were investigated. The success of the aqueous route was realized by introducing tin fluoride (SnF2) instead of the traditional tin chloride (SnCl2) solute. The roles of adding Ga on the GTO’s microstructural, optical, chemical, and electrical performance were comprehensively studied. It was found that Ga can frustrate the crystallization while it augments the optical bandgap (Eg) value of pristine SnO2. More importantly, using Ga could effectively inhibit the formation of oxygen vacancies, thus greatly improving the electrical performance of the GTO TFTs. The amorphous GTO TFTs with a Ga content of 45% exhibited optimum performance, with a saturation mobility (μsat) of 4.26 cm2/V s, an on/off current ratio (Ion/Ioff) >107, and a decent bias stress durability.

Cholinergic neurons in the medial septum (MS) constitute a major source of cholinergic input to the forebrain and modulate diverse functions, including sensory processing, memory, and attention. Most studies to date have treated cholinergic neurons as a single population; as such, the organizational principles underling their functional diversity remain unknown. Here, we identified two subsets (D28K

Transparent amorphous oxide semiconductor (TAOS) represented by a-InGaZnO (IGZO) has achieved their commercial success in the display industry due to its superior material properties (e.g. high mobility (>10 cm 2 V −1 s −1 ), good transparency and excellent uniformity). However, TAOSs with excellent electrical properties are all n-type due to the particular electronic structures of oxide materials. The absence of high performance p-type TAOS limits the device application such as complimentary circuit and is now the largest drawback for oxide electronics. Here, we propose a low-temperature solution method to fabricate p-type transparent amorphous nickel oxide (NiO). The influence of processing parameters such as annealing temperature, precursor concentration, source/drain electrode, and dielectric layer is systematically investigated to maximum the NiO device performance. The optimized NiO TFT exhibits outstanding p-channel behavior, including a high hole mobility of 6.0 cm 2 V −1 s −1 , remarkable on/off current modulation ratio of ∼10 7 , and good subthreshold swing of 0.13 V/decade. The high performance NiO device is attributed to the synergistic optimization of annealing temperature, channel thickness, source/drain electrodes, and dielectric materials. The properties of our p-type TAOS are comparable with that of traditional n-type TAOS.

Perovskite metal oxide (LiNbO3) nanomaterial is explored as a magneto-optic sensor. The electromagnetic interaction is described by magneto-optic modulation associated with vacancy-induced room temperature ferromagnetism. The guiding and propagation through single mode fiber (SMF) is via the excitation of core modes through the material-mediated cavity and further modulated by external magnetic field. The sensitivity and resolution of the sensor are found to be 186 p.m./mT and 0.51 Oe, respectively. The structure with material integrated optical design resulting in a Fabry-Perrot interferometer (FPI), is implemented as an extrinsic sensor, and sensing mechanism is elaborated.

Large-area monolayer WS2 triangles with an average lateral dimension of ~60 μm were grown by chemical vapor deposition (CVD) and a Raman study on the carrier concentration is presented. With temperature-dependent Raman spectra measured over a temperature range of 3 to 520 K, it indicates that the full width at half maximum and intensity of A1g mode were strongly affected by the carrier concentration and corresponding electron-phonon coupling, while the E12g mode was less influenced. In the position-dependent Raman spectra, an increasing number of charge carriers were also discovered along the growth direction. And an upward energy band bending and impurities adsorption were found in the edge regions, which should be taken into consideration for improving the performance of monolayer growth.

Background Death-associated protein kinase 1 (DAPK1) is a widely distributed serine/threonine kinase that is critical for cell death in multiple neurological disorders, including Alzheimer’s disease and stroke. However, little is known about the role of DAPK1 in the pathogenesis of Parkinson’s disease (PD), the second most common neurodegenerative disorder. Methods We used Western blot and immunohistochemistry to evaluate the alteration of DAPK1. Quantitative polymerase chain reaction and fluorescence in situ hybridization were used to analyze the expression of microRNAs in PD mice and patients with PD. Rotarod, open field, and pole tests were used to evaluate the locomotor ability. Immunofluorescence, Western blot, and filter traps were used to evaluate synucleinopathy in PD mice. Results We found that DAPK1 is posttranscriptionally upregulated by a reduction in microRNA-26a (miR-26a) caused by a loss of the transcription factor CCAAT enhancer-binding protein alpha. The overexpression of DAPK1 in PD mice is positively correlated with neuronal synucleinopathy. Suppressing miR-26a or upregulating DAPK1 results in synucleinopathy, dopaminergic neuron cell death, and motor disabilities in wild-type mice. In contrast, genetic deletion of DAPK1 in dopaminergic neurons by crossing DAT-Cre mice with DAPK1 floxed mice effectively rescues the abnormalities in mice with chronic MPTP treatment. We further showed that DAPK1 overexpression promotes PD-like phenotypes by direct phosphorylation of α-synuclein at the serine 129 site. Correspondingly, a cell-permeable competing peptide that blocks the phosphorylation of α-synuclein prevents motor disorders, synucleinopathy, and dopaminergic neuron loss in the MPTP mice. Conclusions miR-26a/DAPK1 signaling cascades are essential in the formation of the molecular and cellular pathologies in PD.

Vertical GaN Schottky barrier diodes (SBDs) were fabricated on Ge-doped free-standing GaN substrates grown by hydride vapor phase epitaxy. Detailed material characterization was performed, and the results indicate the superiority of Ge doping in the GaN, which contributed to the SBDs with lower stress, fewer defects and higher quality. Based on the capacitance-voltage and current–voltage measurements performed, SBDs achieved together with a low turn-on voltage Von (0.71–0.74 V), high current Ion/Ioff ratio (3.9 × 107–2.9 × 108), high Schottky barrier height (0.96–0.99 eV), and high breakdown voltage Vb (802 V for a 100 μm diameter). This shows that vertical GaN SBDs on the Ge-doped substrates are promising candidates for high power applications.

Layered SnSe2 have much attention due to their potential novel applications in electronic devices areas, such as photo-transistors, solar cells and memory devices. We investigate the thermal properties of few layer SnSe2 with capping of Al2O3 layer using the temperature and power-dependent Raman spectroscopy. The first order temperature coefficient of A1g modes of SnSe2 layers on a SiO2/Si substrate was found to be −0.01757 cm−1/K, which is much higher than the corresponding value −0.01270 cm−1/K of SnSe2 with Al2O3 layer. The difference in temperature coefficients is attributed to compressive stress introduced by the Al2O3 stress layer. Meanwhile, the Al2O3 layer significantly increases the thermal conductivity to 3.102 W/mK, which is larger than that of the SnSe2 films without Al2O3 (∼2.378 W/mK). The first principle calculation using CASTP demonstrated that this improvement of thermal conductivity is attributed to the compressive strain. This work suggests an effective way to improve the performances of SnSe2 based devices, and also need to understand the vibrational properties and electron-phonon interactions at the interface of Al2O3 and SnSe2 layers.

Zn1-xCdxO films with different Cd contents obtained by controlling the growth oxygen pressure (Op) were deposited on both c-sapphire (Al2O3) substrates and p-GaN substrates, by means of the pulsed laser deposition (PLD) method. Photoluminescence (PL) measurement revealed that the variation of Op influenced the amount of Cd doping into Zn1-xCdxO films deposited on Al2O3, leading tunable luminescence from the ultraviolet (UV) to blue emission extended to the green band. Then all the fabricated n-Zn1-xCdxO/p-GaN heterojunction possessed good ohmic contacts and exhibited typical rectifying characteristic of the diode. Indeed, the high luminescence from the ZnCdO layer could be attained by inserting a MgO insulator to the heterojunction interface. The fabrication of tunable n-Zn1-xCdxO/p-GaN heterojunction light-emitting diodes is available which was supported by the results of electroluminescence (EL) experiment.

MoS2 based hybrid structures have much attention due to their novel structures and potential applications in diverse areas, such as solar energy conversion, thermoelectric power generation and photo-transistors. In the present work, we have fabricated a novel sandwich structure of MoS2/InSe-nanoparticles (NPs)/MoS2 layers on SiO2/Si substrate by a combination of chemical vapor deposition and physical vapor deposition methods. The morphology of these structures was also studied using scanning electron microscopy. In addition, we have also explored the thermal properties of these hybrid sandwich structures using temperature and power-dependent Raman spectroscopy. For MoS2/InSe-NPs/MoS2 sample, the first-order temperature coefficients of E12g and A1g modes were found to be −0.01722 and −0.01575 cm−1/K, respectively, which are significantly large compared to MoS2 layers without InSe-NPs (i.e. MoS2/MoS2 sample). Further, the thermal conductivity of MoS2/InSe-NPs/MoS2 and MoS2/MoS2 samples on SiO2/Si substrate was extracted as ∼102.3 and ∼81.7 W/m-K, respectively. This work suggests an effective way to form a novel 2D-MoS2 based sandwich structure with semiconductor/metal-NPs; opening up a new scenario to understand the electronic structure of the hybrid structure, and the local strain introduced by NPs. Electron-phonon interactions at an interface can have significant effects on electrical/thermal transport through the optoelectronic devices.

By employing localized surface plasmon resonance (LSPR), the near band edge (NBE) emission intensity of ZnO films were greatly varied, while defect emission remained almost the same. This photoluminescence (PL) intensity enhancement or reduction is tunable by changing the position of Ag nanoparticles (NPs) relative to the ZnO films. The remarkable variation of the NBE emission was investigated deeply. These experimental results reveal that the Ag NPs play a key role in tuning the PL performance of the semiconductor material, where LSPR occurs.

In2Se3 nanostructures have attracted much attention due to their potential applications in diverse areas, such as solar energy conversion, thermoelectric power generation, phase change random access memories, photodetectors, and optoelectronics in the visible region. In the present work, we have fabricated various In2Se3 nanostructures on SiO2/Si substrate using a simple and single-step physical vapor deposition (PVD) method, without using metal seed layer on the substrates. Morphology, structure and phase of the as-grown In2Se3 nanostructures have been carried out using scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS) and Raman spectroscopy, respectively. In addition, we have also explored thermal properties of In2Se3 nanostructures on SiO2/Si substrate using temperature and power dependent Raman spectroscopy. Further, the thermal conductivity of nanoparticles, nanospheres, and rod like flowers at room temperature were found to be ∼37.6, ∼39.5, and ∼15.6 W/m-K, respectively. This work suggests an effective way to form various novel nanostructures, opening up a new scenario to understand the vibrational properties and electron-phonon interactions of In2Se3 nanostructures.

Background and objectives Vicagrel, a novel thienopyridine antiplatelet agent, is an analogue of clopidogrel in development for the treatment of acute coronary syndromes. This study investigated the pharmacokinetic properties of vicagrel after single oral dosing with a direct comparison with clopidogrel in healthy Chinese subjects in the first two phase I clinical studies. The relationship between the exposure to the active metabolite and the platelet reactivity was also assessed for vicagrel. Methods Study A was a single-ascending-dose study of vicagrel (5–75 mg) compared with clopidogrel (75 mg) in 67 healthy volunteers. Study B was a randomized, two-period, crossover, loading-dose study of vicagrel 20 mg compared with clopidogrel 300 mg in 12 healthy subjects. Plasma concentrations of three common metabolites of vicagrel and clopidogrel, the active thiol metabolite H4, the inactive thiol metabolite H3, and the S-methylated form of H3 (SM3, the major metabolite of vicagrel), were determined using a validated UHPLC–MS/MS method. The relationship between the AUC0−t of active H4 and the P2Y12 reaction units at 4 h after administration of vicagrel was investigated. Blood concentrations of vicagrel were determined after a single oral administration of vicagrel 25 mg to two healthy Chinese subjects. Results In the single-ascending-dose study, vicagrel was metabolized rapidly with the median tmax for the three metabolites, namely, H4, H3, and SM3, ranging from 0.25–1.75 h. The pharmacokinetics of the three metabolites for vicagrel were linear across the dose range of 5–75 mg, with the mean Cmax and AUCs for H4 and H3 increasing in an approximately 1:1 dose-proportional manner and for SM3 increasing in a Conclusions Vicagrel was rapidly and extensively metabolized, and the levels of the parent drug in circulation were very low. The pharmacokinetics of the three metabolites of vicagrel were linear and predictable across the dose range of 5–75 mg. The AUC of active H4 was apparently associated with the P2Y12 reaction units for vicagrel. For active H4, vicagrel 5 mg produced similar exposure (AUC) with more rapid appearance compared with clopidogrel 75 mg, and vicagrel 20 mg produced even slightly higher exposure (AUC) with more rapid appearance compared with clopidogrel 300 mg in humans. Trial Registration: CTR20150346, CTR20160379.

We reported the low-temperature high performance IGZO TFTs by solution processing. The influence of IGZO composition over broad range on thin films and devices properties were investigated by a wide range of characterization techniques. The schematic of TFT solution-processed IGZO TFTs mobility with different compositions has been obtained. In order to achieve decent TFT performance, the In content should be much high for solution-processed IGZO TFTs. The optimal solution-processed IGZO TFTs with In:Ga:Zn = 5:1:1 composition exhibited a large mobility of 9.1 cm2 V−1 s−1, low subthreshold swing of 0.22 V/decade, and high on/off ratio of 106 at 300 °C processing temperature.

The effect of oxygen pressure on deposition orientation and the UV response characteristics of the β-Ga2O3 thin film by the Pulse Laser Deposition (PLD) method were studied. The β-Ga2O3 thin film deposited mainly along ( 2 ¯ 01 ) orientation at 0.5 Pa oxygen pressure, however it deposited more along (400) orientation when the oxygen pressure increased from 0.5 Pa to 2 Pa. The decrease in the migration energy of reactive Ga and O atoms from Ga2O3 target at higher oxygen pressure is the main reason for the change in the orientation of the β-Ga2O3 thin film. The β-Ga2O3 thin film that was constituted mainly by ( 2 ¯ 01 ) and (400) orientations β-Ga2O3 was made at 2 Pa, where the band gap of the β-Ga2O3 thin film is wider than the ( 2 ¯ 01 ) orientation ones deposited at smaller oxygen pressure, and the maximum response of the β-Ga2O3 thin film shifted considerably from 255 nm to 240 nm compared with ( 2 ¯ 01 ) orientation β-Ga2O3 thin film. Because the Idark of the UV detector based on the mix-orientation β-Ga2O3 thin film is just 2.53 nA under 25 V bias voltage, which is much smaller than that of the ( 2 ¯ 01 ) β-Ga2O3 based detector, the Iuv/Idark of the mix-orientation β-Ga2O3–based detector reached 2500 at 25 V bias voltage. This value is much higher than the ( 2 ¯ 01 ) β-Ga2O3–based detector both in our experiments and in reported results. Wider band gap (400) β-Ga2O3 and relative higher density of boundaries at the interfaces between (400) and ( 2 ¯ 01 ) β-Ga2O3 are the main reasons for the smaller Idark and the higher Iuv/Idark of the β-Ga2O3 UV detector deposited at 2 Pa. The β-Ga2O3 thin film deposited along multiple orientations at oxygen pressure over 2Pa, the UV response, and Iuv of the β-Ga2O3 thin films deposited at higher oxygen pressure was much smaller than the one deposited at 2 Pa, and the Iuv/Idark was also much smaller. In addition, the UV β-Ga2O3 detector that composed of both (400) and ( 2 ¯ 01 ) β-Ga2O3 showed similar response time (0.8 us) and much smaller decay time (80 us) compared with the ( 2 ¯ 01 ) β-Ga2O3–based detector, which was also much faster than the reported results. Therefore, when appropriate numbers of (400) β-Ga2O3 were mixed into the ( 2 ¯ 01 ) β-Ga2O3 thin film, the mix-orientation β-Ga2O3–based UV detector showed a much lower noise level, much higher signal/noise ratio, and much faster decay speed at shorter wavelength UV light compared with a single ( 2 ¯ 01 ) β-Ga2O3–based based UV detector.

Vicagrel, an analog of clopidogrel, is a novel thienopyridine P2Y12 antagonist in clinical development in China for the treatment of acute coronary syndromes. Vicagrel and clopidogrel are prodrugs requiring metabolic activation to produce a pharmacologically active thiol metabolite (H4) in vivo. The formation of H4 from vicagrel in humans is promising more efficient and consistent than that from clopidogrel. After oral dosing of vicagrel or clopidogrel to humans, the active thiol metabolite H4 and two inactive metabolites closely related to H4 formation (the thiol metabolite H3 and the S-methylated metabolite SM3) were observed in plasma; SM3 was the most abundant drug-related component of vicagrel in circulation. In this study, a sensitive, rapid, and reliable UHPLC-MS/MS method was developed for the simultaneous determination of derivatized H3 (MP-H3), derivatized H4 (MP-H4), and SM3 in human plasma to investigate the pharmacokinetics of vicagrel in healthy subjects compared with clopidogrel. After extracted from 50μL of plasma by simple protein precipitation, the analytes and stable isotope-labeled internal standards were separated on an Acquity UPLC BEH C18 column (100mm×2.1mm, 1.7μm). The mobile phase was acetonitrile-water-formic acid (45:55:0.0275, v/v/v) delivered at a flow rate of 0.45mL/min under isocratic elution. The total chromatographic run time was 6min. MP-H3, MP-H4, and SM3 were separated from their corresponding isomers under the chromatographic conditions. Mass spectrometric detection was conducted in multiple reaction monitoring mode on an AB Sciex Qtrap 5500 System using a positive electrospray ionization interface. The calibration curves were linear in the following ranges: 0.100-200ng/mL for MP-H3 and MP-H4 and 1.00-1000ng/mL for SM3. The intra- and inter-day accuracy and precision for each analyte at all concentrations were within acceptable limits (±15%). The validated method was successfully applied to compare the pharmacokinetics of vicagrel and clopidogrel after a single oral administration to healthy subjects in the first-in-human study of vicagrel.

Two-dimensional thin layers of indium selenide (InSe) have attracted much attention due to their potential applications in optoelectronics as highly responsive photo-detectors and field-effect transistors. In the present work, we explore thermal properties of InSe thin layers on a high-k substrate with a thin SiO2 passivation layer using temperature and power dependent Raman spectroscopy. The first order temperature coefficients for in-plane (E12g) and out-of-plane (A21g) modes of InSe few-layers on a Al2O3 substrate were found to be −0.00507 and −0.00310 cm−1/K, respectively, which are much smaller than the corresponding values −0.00612 and −0.00528 cm−1/K of similarly prepared sample on SiO2 substrate. The difference in temperature coefficients is attributed to compressive strain introduced by the Al2O3. Further, the average thermal conductivity of a 4 nm thin InSe layer on the Al2O3 substrate at room temperature was found to be ∼53.4 W/m-K, which is significantly larger than those of InSe layers prepared on SiO2 substrate (∼28.7 W/m-K). The existed interface charges between the Al2O3 and InSe layers cause the observed improvement of thermal conductivity by electron-phonon interactions.

ZnO:Al (AZO) and a-Ga2O3 thin films were successively deposited on a sapphire substrate by magnetron sputtering and the photoelectric properties of AZO/a-Ga2O3 heterojunction vertical structure to solar blind ultraviolet light were investigated. The device shows a high photo-to-dark current ratio (2.2 × 103), low dark current (11.4 nA), large responsivity (67.26 A/W) and fast response and recovery times of 1.53 μs and 2.25 ms under 254 nm light illumination at 10 V. Additionally, the device exhibits an obvious self-powered effect with light-dark current ratio (183.3) and the responsivity (2.92 × 10−2 A/W) at 0 V. The high response is attributed to the separation of photogenerated electron-hole pairs due to built-in field in the depletion width of AZO and Ga2O3. The analysis shows that there exists a quasi-Zener tunneling internal gain mechanism, which increases the performance of the device. The comprehensive performance of the device implied a wide potential in optoelectronics applications.

The disadvantages of the low on/off current ratio (Ion/off) and high leakage current in ZnO-based thin-film transistors (TFTs) impede its development to realize industrial production for replacing Si-TFTs. In this work, we fabricated a high performance MgZnO/ZnO dual-active-layer TFTs (DAL-TFTs) through systematic optimize the synthesis conditions. The optimized Mg0.2Zn0.8O/ZnO TFTs presents high mobility of 21.1 cm2V−1s−1 with a high Ion/off of 1.5 × 108, which is much higher than that of ZnO-based TFTs. The results indicate that high carrier concentration ZnO close to the insulation layer ensures the excellent mobility of MgZnO/ZnO DAL-TFTs and low carrier concentration MgZnO layer can reduce the off-state current of the device, and increase the switching ratio of the device. Our results indicate the MgZnO/ZnO composite is a promising candidate for high performance TFTs and other electronic devices.

Urea electrolysis enables simultaneous energy-saving hydrogen production and wastewater purification at a small thermodynamic potential of 0.37 V; however, the total energy-utilization efficiency is still substantially restricted by the sluggish kinetics of the urea oxidization reaction (UOR) at the anode. In this work, an electrochemical tuning strategy has been employed to obtain a Ni (III)-enriched catalyst by starting from NiMoO4∙xH2O nanorod arrays. It has been found that the electrochemical tuning not only modifies the valency state of Ni but also causes a dramatic change in stoichiometry and microstructure of the material, leading to significantly improved activities for UOR under alkaline conditions. Notably, the obtained catalyst delivers a current density of 100 mA cm−2 for UOR at the potential of only 1.36 V vs RHE, which surpasses the best-reported values for UOR catalysis at the same applied potential, demonstrating the great promise of the electrochemical tuning strategy in rational modifications of material towards promoted electrocatalysis.

Histone deacetylase 2 (HDAC2) plays a major role in the epigenetic regulation of gene expression. Previous studies have shown that HDAC2 expression is strongly increased in Alzheimer’s disease (AD), a major neurodegenerative disorder and the most common form of dementia. Moreover, previous studies have linked HDAC2 to Aβ overproduction in AD; however, its involvement in tau pathology and other memory-related functions remains unclear. Here, we show that increased HDAC2 levels strongly correlate with phosphorylated tau in a mouse model of AD. HDAC2 overexpression induced AD-like tau hyperphosphorylation and aggregation, which were accompanied by a loss of dendritic complexity and spine density. The ectopic expression of HDAC2 resulted in the deacetylation of the hepatocyte nuclear factor 4α (HNF-4A) transcription factor, which disrupted its binding to the miR-101b promoter. The suppression of miR-101b caused an upregulation of its target, AMP-activated protein kinase (AMPK). The introduction of miR-101b mimics or small interfering RNAs (siRNAs) against AMPK blocked HDAC2-induced tauopathy and dendritic impairments in vitro. Correspondingly, miR-101b mimics or AMPK siRNAs rescued tau pathology, dendritic abnormalities, and memory deficits in AD mice. Taken together, the current findings implicate the HDAC2/miR-101/AMPK pathway as a critical mediator of AD pathogenesis. These studies also highlight the importance of epigenetics in AD and provide novel therapeutic targets.

MSM structure UV detectors were fabricated on mixed-phase MgZnO thin films with (200) cubic MgZnO/hexagonal MgZnO and (111) cubic MgZnO/hexagonal MgZnO interfaces by PLD method. Under 25 V bias voltage, the maximum responsivity of the mix-phase MgZnO based detector with (002) cubic MgZnO/hexagonal MgZnO interfaces reached 8 A/W at 256 nm because of 3809% internal gain of the detector at solar-blind UV light, which is two order of magnitude bigger than the detector with (111) cubic MgZnO/hexagonal MgZnO interfaces. The higher density of interface states between (200) cubic and hexagonal MgZnO grains in the mix-phase MgZnO thin film is main reason for its big internal gain and high solar-blind UV response. The Idark of the mixed-phase MgZnO based detector with (111) cubic MgZnO/hexagonal MgZnO interfaces is much smaller and the Ilight/Idark of which is higher because of the higher interfaces barrier at (111) cubic MgZnO/hexagonal MgZnO interfaces, so the detector could effectively detect faint solar-blind UV signal more under strong noise background.

We investigated the thermal properties of few-layer Mo0.5W0.5S2 using a series of samples with different kinds of capping layers. Temperature-dependent Raman measurements were conducted in the range of 300–500 K, with power-dependent measurements also carried out. It indicated, for the few-layer Mo0.5W0.5S2, the temperature coefficients of the WS2-like E12g mode, MoS2-like E12g mode and A1g mode were −0.0155 cm−1/K, −0.0146 cm−1/K, and −0.0130 cm−1/K, respectively. And the thermal conductivity was estimated to be 44.8 W/mK. Moreover, the Mo0.5W0.5S2 samples coated with capping layers (ZrO2, HfO2) both showed a better thermal stability and a larger thermal conductivity than the one without. The results revealed that the capping layer should be an important factor in the thermal property. Keywords: Mo0.5W0.5S2, TMDs, Thermal properties, High temperature, Capping layers, Raman

We prepared ZnO:H thin films in Ar + H2 atmosphere with substrate at room temperature by magnetron sputtering, the effect of H2 flow ratio on the properties of thin films and the performance of ZnO:H thin-film transistors (ZnO:H-TFTs) were investigated. Hydrogen could act as a defect passivator and a shallow donor in ZnO films, which not only increases the carrier concentration but also reduces the interface trap density, therefore improving the TFT performance. Compared with pristine ZnO-TFT, the optimal ZnO:H-TFT exhibits great enhancement, with the saturation mobility increasing from 2.17 cm2/V⋅s to 5.17 cm2/V⋅s, the on/off ratio increasing from 3.47 × 105 to 4.98 × 106, the threshold voltage reducing from 15.12 V to 6.03 V. Meanwhile, the positive and negative bias stability is also improved from ΔVth = 3.89 V and −6.35 V to 1.74 V and −3.72 V, respectively. Our results show that introducing hydrogen into the sputtering atmosphere to achieve hydrogen doping is a simple and effective method to improve the performance of ZnO-TFTs. Furthermore, the high-performance ZnO:H-TFTs fabricated at room temperature have great potential in the field of flexible electronics.

This work reports a simple, time efficient, template-free solvothermal and environmentally friendly method for the synthesis of V2O5 nanospheres (NSs) for xylene gas detection. The four types of V2O5-5, V2O5-7, V2O5-9 and V2O5-11 NSs have been synthesized and tested toward xylene in concentration ranging from 1 ppm to 300 ppm. The V2O5-7 sensor exhibits excellent sensing response of 2.75 toward 100 ppm xylene gas within fast response time of 21 s with obtained limit of detection (LOD) of 1 ppm at optimal operating temperature 290 °C. The sensing mechanism is based on an interaction of V2O5 NSs towards xylene through chemical reaction with adsorbed oxygen species present on V2O5 NSs, resulting in a thinner depletion layer and a lower potential barrier which further leads to decrease in sensor resistance. These experimental results suggest that the V2O5 NSs based sensors have potential to fulfill the demands in the gas sensing field.

Mossy cells (MCs) are a unique group of excitatory neurons in the hippocampus, a brain region important for emotion, learning, and memory. Due to the lack of a reliable method to isolate MCs from other cell types, how MCs integrate neural information and convey it to their synaptic targets for engaging a specific function are still unknown. Here, we report that MCs control the efficacy of spatial memory retrieval by synapsing directly onto local somatostatin-expressing (SST) cells. MC-SST synaptic transmission undergoes long-term potentiation (LTP), requiring Gria2-lacking Ca2+-permeable anti-α-amino-3-hydroxy-5-methyl-4-isoxazole-propionic acid (AMPA) receptor (Ca2+AR). A long noncoding RNA (Gria2I) is associated with Gria2 transcriptional repressors in SST cells. Silencing Gria2I induces Gria2 transcription, blocks LTP of MCs-SST synaptic transmission, and reduces the efficacy of memory retrieval. Thus, MCs directly and functionally innervate local SST neurons, and this innervation controls the efficacy of spatial memory retrieval by Gria2I inhibition of Gria2 transcription.

In this work, we report parts per billion (ppb) NO2 gas detection by utilizing zinc oxide/reduced graphene oxide (ZnO/rGO) heterostructure through a chemiresistive approach. The sensing material is carefully investigated through numerous characterization techniques. The experimental results indicated that the designed sensor shown good linearity in low ppb range of nitrogen dioxide (NO2) gas. The sensor exhibited very high response of 33.11 at 2.5 ppm in 182 s with obtained detection limit down to ppb at relatively low optimal operating temperature of 110 °C. The remarkable performance of ZnO/rGO heterostructure towards NO2 and negligible cross-response to other interfering gases along with high repeatability and long-term stability of the sensor is investigated. Due to many reactive sites and high transport capability of rGO along with high gas adsorption of ZnO nanospheres which attributes to the favorable charge transfer at ZnO/rGO interface under exposure of NO2 gas which leads to modulate the energy band structure. This study shows that the simple, cost-effective synthesis method along with easy-fabricated and deployable sensor can be applied in many industrial and environmental applications.

High-resolution x -ray photoelectron spectroscopy (XPS) was employed to characterize the energy band alignment between TiO 2 /multilayer (ML)-MoS 2 . The TiO 2 film and ML-MoS 2 film was grown by an atomic layer deposition (ALD) and chemical vapor deposition (CVD), respectively. The effect of CHF 3 plasma treatment on the band alignment between TiO 2 /ML-MoS 2 was evaluated. It was found that the valence band offset (VBO) and a conduction band offset (CBO) of TiO 2 /ML-MoS 2 interface was changed from 2.28 eV to 2.51 eV, and from 0.28 eV to 0.51 eV, respectively for the sample with CHF 3 plasma treatment. With the CHF 3 plasma treatment, the down-shift of Mo 3d core level binding energy results in a bend-up of energy potential on the MoS 2 side, leading to 0.23 eV ΔE C difference between the control and the sample with CHF 3 plasma treatment, which is caused by the interfacial layer in rich of F element. The physics details of the band alignment at TiO 2 /ML-MoS 2 interface will provide a guide for the MoS 2 based electronic device design.

Volatile organic compounds (VOCs) monitoring is a vital need for many industrial and environmental air quality monitoring applications. We proposed and demonstrated a dual-cavity Fabry-Perot interferometric (DFPI) sensors fabricated by using a polarization maintaining fiber (PMF) immobilized with graphene, PMMA and graphene/PMMA composite for detection of various volatile gases. The optical properties of these materials changes when exposed to different VOCs, which proportionally leads to wavelength and power shift in an interference spectrum due to effective change in refractive index of graphene and swelling of PMMA, respectively. The experimental results are best fitted with models based on Langmuir adsorption isotherm and Hansen solubility parameters. This study focuses on insight into the physical/chemical interaction of volatile gases with versatile sensing materials along with new optical fiber configuration approach, which could be explored for remote detection and air quality monitoring.

Perovskite mixed valence magnetic (La0.7Ba0.3MnO3) material is explored as a magneto-optical sensor by integrating onto the surface of an optical fiber. The guiding properties of core modes excited by the material cavity are modulated by the external magnetic field. The experimental results concluded that the device exhibits linear response to applied magnetic field strength in the range of 0–20 mT with the sensitivity of 228 pm/mT and resolution of 0.87 Oe. Blue-shift phenomenon has been observed in the interference pattern, when a magnetic field is applied. Such wavelength shift is attributed to the influences of magneto-optical properties on optical-wave propagation. The results reveal the feasibility of developing an index-tuneable magneto-optical sensor using perovskite magnetic material.

Indium dysprosium oxide (InDyO) thin-film transistors (TFTs) are demonstrated by aqueous solution processing. The structure, morphology, chemical, oxygen defects, optical, and electrical properties of InDyO films with the change of Dy doping contents are systematically studied. It is observed that Dy doping could effectively improve the off current and the bias stress stability of the In2O3 devices due to the suppression of oxygen vacancies (VO). The optimized InDyO TFTs with 10 mol% Dy doping exhibit excellent electrical characteristics, including a μ of 7.60 cm2 V−1 s−1, high Ion/Ioff >108, small SS of 0.77 V/dec, Vth of 1.78 V, and excellent bias stress stability. Therefore, the InDyO TFTs grown from aqueous solution enable the development of environmentally friendly and large area electronics.

Present work proposes the insight towards synthesis of flower-like vanadium oxide hierarchical nanostructures (V2O5 HNs) through a simple and template-free hydrothermal method and their utilization as a potential xylene gas sensing materials. XRD and XPS analysis supports to the configuration of highly crystalline orthorhombic phase of V2O5. Surface morphologies of V2O5 were controlled through varying the reaction times during hydrothermal synthesis. SEM and TEM studies undoubtedly corroborates that the flower-like V2O5 HNs (3–5 μm in diameters) are composed of large number of nanosheet- and nanoneedle-type structures. BET and BJH analysis supports to the mesoporous character of V2O5 HNs with specific surface area of 19.5291 m2/g. Gas sensing studies on as-fabricated V2O5 HNs sensors were performed towards a various target gases, temperatures, and varying concentrations thoroughly and described. Gas sensing studies demonstrate that the flower-like V2O5 HNs sensors are selective and effective towards xylene @300 °C. Among various V2O5 HNs sensors, the sensor based on V2O5-3 exhibits maximum response of 3.03 to 500 ppm xylene together with good response repeatability and long term stability (towards 100 ppm, Ra/Rg = 2.20) @300 °C. Finally, the selective detection of xylene using as-grown flower-like V2O5 HNs can cover the road in the direction of the development of sensing systems for the acute detection and monitoring of toxic xylene.

The development of defined hierarchical transition metal oxide nanostructures has attracted remarkable attention due to their superior chemiresistive gas sensing performances. In the present study, vertically aligned zinc oxide nanorods (ZnO-NRs) were grown by chemical vapor deposition (CVD) and precise decoration with palladium nanoparticles (Pd-NPs) on their surfaces, at different deposition times, was done through unique RF magnetic sputtering followed by annealing. The effect of different Pd-NPs loadings on structure, surface morphology, elemental composition, and chemiresistive C2H5OH gas sensing properties of CVD-mediated pristine ZnO-NRs was elucidated thoroughly and accounted. As-fabricated pristine and Pd-loaded ZnO-NRs sensors are sensitive towards ethanol (C2H5OH) at 260 °C. Moreover, gas sensing investigations revealed that the C2H5OH response of pristine ZnO NRs was enhanced strongly due to Pd-decoration. Such a response enhancement is mainly attributed to the catalytic activity of Pd-NPs. It is confirmed that the influence of Pd-NPs on ZnO-NRs sensor is normally to strengthen the amount of chemisorbed oxygen on ZnO-NRs surface and enhance the C2H5OH response. Present work can motivate research advancement on precise designing of innovative one dimensional and related nanostructures for the application of selective chemiresistive gas sensors.

Effect of temperature on crystal and optical characteristics of MgZnO thin films by PLD method was studied. MgZnO thin film that contained cubic ZnO on the surface was made at lower temperature, which could absorb UV light ranged from 230 to 300 nm. This curious phenomenon is reason from the vertical separation of Zn atoms from cubic structure MgZnO lattice through vertical migration under vacuum condition during growth process. And because the solid solubility of Zn atoms in cubic MgZnO increased with temperature, the cubic ZnO didn't form in MgZnO thin films deposited at higher temperature. The cubic ZnO could just exist through special separating out process during growth process, which would transformed gradually from cubic structure to hexagonal structure when annealed at temperature from 450 °C to 850 °C under atmospheric conditions.

Mg 1− x Zn x O thin films were deposited under different pressures during the growth process, which is modulated by different Ar/O 2 flow ratio. When growth pressure increases, the growth orientation of MgZnO thin film changed from (200) to (111) because of the decrease in migration energy of reactive Mg, Zn and O atoms from MgZnO target material. The band gap of MgZnO thin films decreased when growth pressure increased from 2 Pa to 6 Pa, which is reason from more Zn atoms combined with O atoms in (111) orientation MgZnO crystal lattice in MgZnO thin film deposited at higher pressures. But when the growth pressure increased from 6 Pa to 7 Pa, the band gap value of MgZnO thin films increased because less Zn atoms than Mg atoms combined with O atoms in MgZnO crystal lattice at higher pressures with the same (111) orientation.

In this paper, photoluminescence (PL) of ZnO thin films prepared on c-Al2O3 substrates by the pulsed laser deposition (PLD) method at different O2 partial pressures is investigated. For all samples, a narrow ultraviolet (UV) emission and a broad visible emission can be observed at room-temperature (RT). With increasing O2 partial pressures from 0.2 to 5 Pa, the intensity ratio of the UV to visible emissions increases, and the energy positions of the UV emission band shift to the high energy side. It is noted that the visible part includes two emission bands of green luminescence (GL) and yellow luminescence (YL), in which the GL emission is strong at low oxygen pressure and the YL emission becomes dominant at high O2 partial pressures. The temperature-dependent PL spectra show that the UV emission is composed of two bands labeled FX and FA. The dependences and possible assignments of these PL bands are briefly discussed.

Summary: Retroactive interference (RI) occurs when new incoming information impairs an existing memory, which is one of the primary sources of forgetting. Although long-term potentiation (LTP) reversal shows promise as the underlying neural correlate, the key molecules that control the sensitivity of memory circuits to RI are unknown, and the developmental trajectory of RI effects is unclear. Here we found that depotentiation in the hippocampal dentate gyrus (DG) depends on GluN2A-containing NMDA receptors (NMDARs). The susceptibility of LTP to disruption progressively increases with the rise in the GluN2A/GluN2B ratio during development. The vulnerability of hippocampus-dependent memory to interference from post-learning novelty exploration is subject to similar developmental regulation by NMDARs. Both GluN2A overexpression and GluN2B downregulation in the DG promote RI-induced forgetting. Altogether, our results suggest that a switch in GluN2 subunit predominance may confer age-related differences to depotentiation and underlie the developmental decline in memory resistance to RI. : Ge et al. report that the NMDA receptor GluN2A/GluN2B subunit ratio determines the sensitivity of strengthened neuronal connections to depotentiation. As the ratio rises during development, memories become more vulnerable to disruption by post-learning interference. These findings help to illuminate the mechanism by which forgetting rates may vary with age. Keywords: forgetting, retroactive interference, depotentiation, NMDA receptor

Cubic MgZnO thin films were deposited on amorphous quartz substrate by PLD method. Effect of deposition pressure on preferential orientation and optical absorption characteristics of MgZnO thin films were studied. The preferred orientation of cubic MgZnO changed from (2 0 0) to (1 1 1) when deposition pressure increased, and absorption edges of which shift to longer wavelength direction because Mg content of MgZnO thin film decreased. Cubic MgZnO showed much better crystal quality and preferential orientation growth characteristics on proper crystal substrate, because on this substrate the preferred orientation of cubic MgZnO is accordance with that grown in free growth mode on amorphous substrate at special air pressure.

EPAC proteins are the guanine nucleotide exchange factors that act as the intracellular receptors for cyclic AMP. Two variants of EPAC genes including EPAC1 and EPAC2 are cloned and are widely expressed throughout the brain. But, their functions in the brain remain unknown. Here, we genetically delete EPAC1 (EPAC1(-/-)), EPAC2 (EPAC2(-/-)), or both EPAC1 and EPAC2 genes (EPAC(-/-)) in the forebrain of mice. We show that EPAC null mutation impairs long-term potentiation (LTP) and that this impairment is paralleled with the severe deficits in spatial learning and social interactions and is mediated in a direct manner by miR-124 transcription and Zif268 translation. Knockdown of miR-124 restores Zif268 and hence reverses all aspects of the EPAC(-/-) phenotypes, whereas expression of miR-124 or knockdown of Zif268 reproduces the effects of EPAC null mutation. Thus, EPAC proteins control miR-124 transcription in the brain for processing spatial learning and social interactions.

SummaryN-methyl-D-aspartate (NMDA) receptors constitute a major subtype of glutamate receptors at extrasynaptic sites that link multiple intracellular catabolic processes responsible for irreversible neuronal death. Here, we report that cerebral ischemia recruits death-associated protein kinase 1 (DAPK1) into the NMDA receptor NR2B protein complex in the cortex of adult mice. DAPK1 directly binds with the NMDA receptor NR2B C-terminal tail consisting of amino acid 1292-1304 (NR2BCT). A constitutively active DAPK1 phosphorylates NR2B subunit at Ser-1303 and in turn enhances the NR1/NR2B receptor channel conductance. Genetic deletion of DAPK1 or administration of NR2BCT that uncouples an activated DAPK1 from an NMDA receptor NR2B subunit in vivo in mice blocks injurious Ca2+ influx through NMDA receptor channels at extrasynaptic sites and protects neurons against cerebral ischemic insults. Thus, DAPK1 physically and functionally interacts with the NMDA receptor NR2B subunit at extrasynaptic sites and this interaction acts as a central mediator for stroke damage.

Summary Aberrant cell-cycle activity and DNA damage are emerging as important pathological components in various neurodegenerative conditions. However, their underlying mechanisms are poorly understood. Here, we show that deregulation of histone deacetylase 1 (HDAC1) activity by p25/Cdk5 induces aberrant cell-cycle activity and double-strand DNA breaks leading to neurotoxicity. In a transgenic model for neurodegeneration, p25/Cdk5 activity elicited cell-cycle activity and double-strand DNA breaks that preceded neuronal death. Inhibition of HDAC1 activity by p25/Cdk5 was identified as an underlying mechanism for these events, and HDAC1 gain of function provided potent protection against DNA damage and neurotoxicity in cultured neurons and an in vivo model for ischemia. Our findings outline a pathological signaling pathway illustrating the importance of maintaining HDAC1 activity in the adult neuron. This pathway constitutes a molecular link between aberrant cell-cycle activity and DNA damage and is a potential target for therapeutics against diseases and conditions involving neuronal death.

In this paper, we have prepared Schottky type ZnO metal–semiconductor–metal (MSM) ultraviolet (UV) detector. The structural, electrical, and optical measurements were carried out. The detector exhibited a peak responsivity of 0.337 A/W at 360 nm and the dark current was about 1 nA under 3 V bias. An ultraviolet–visible rejection ratio was obtained about more than four orders of magnitude from the fabricated detector. The 10–90% rise and fall time were 20 ns and 250 ns, respectively. We proposed that the detector had shown a gain, which was attributed to the trapping of hole carriers at the semiconductor–metal interface.

Ni thin films were electrodeposited on n-Si (100) substrate from the electrolytes containing Ni(CH 3 COO) 2 and CH 3 COONH 4 at room temperature. The scanning electron microscope images of the films reveals the uniform distribution of the nickel all over the substrate surface, which illustrates that the fine Ni films on large scales could be obtained through the method of electrodeposition. Vibrating sample magnetometer measurement with the applied field parallel to the surface shows obvious hysteresis loops of the magnetic thin films. The morphology and magnetism of the Ni thin films evolves with the deposition time increasing. The effect of deposition conditions on the properties of the Ni thin films is investigated.

Mg x Zn 1− x O alloy films were prepared on sapphire substrates using Ar and N 2 as the sputtering gases. The effect of the sputtering gas on the structural, optical and electrical properties of the Mg x Zn 1− x O films was studied. By using N 2 as the sputtering gas, the Mg x Zn 1− x O film shows p-type conductivity and the band gap is larger than that employing Ar as the sputtering gas. The reason for this phenomenon is thought to be related to the reaction between N–O or N–Zn, and the N-doping.