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The ability to fight or flee from a threat relies on an acute adrenergic surge that augments cardiac output, which is dependent on increased cardiac contractility and heart rate. This cardiac response depends on [beta]-adrenergic-initiated reversal of the small RGK G protein Rad-mediated inhibition of voltage-gated calcium channels ([Ca.sub.v]) acting through the [Ca.sub.v][beta] subunit. Here, we investigate how Rad couples phosphorylation to augmented [Ca.sup.2+] influx and increased cardiac contraction. We show that reversal required phosphorylation of [Ser.sup.272] and [Ser.sup.300] within Rad's polybasic, hydrophobic C- terminal domain (CTD). Phosphorylation of [Ser.sup.25] and [Ser.sup.38] in Rad's N-terminal domain (NTD) alone was ineffective. Phosphorylation of [Ser.sup.272] and [Ser.sup.300] or the addition of 4 Asp residues to the CTD reduced Rad's association with the negatively charged, cytoplasmic plasmalemmal surface and with [Ca.sub.v][beta], even in the absence of [Ca.sub.v][alpha], measured here by FRET. Addition of a posttranslationally prenylated CAAX motif to Rad's C-terminus, which constitutively tethers Rad to the membrane, prevented the physiological and biochemical effects of both phosphorylation and Asp substitution. Thus, dissociation of Rad from the sarcolemma, and consequently from [Ca.sub.v][beta], is sufficient for sympathetic upregulation of [Ca.sup.2+] currents., Introduction Calcium influx through voltage-gated L-type [Ca.sup.2+] channels ([Ca.sub.v]1.2) is an essential link in the chain of signals that trigger the contraction of every heartbeat. Norepinephrine released from sympathetic neurons [...]

With the rapid technological development of thin-film transistors (TFTs), TFTs based on silicon are facing inherent limitations. Finding suitable materials and developing new techniques for fabricating high-performance TFTs is of paramount importance. In this report, a preparation technique for thin films by electrospinning was proposed, in which the thin films were prepared by the melting of nanofibers at low temperature, termed nanofiber-to-films (NTF). The In2O3 and Al2O3 thin films were fabricated by a NTF process and acted as the channel and gate dielectric of TFTs, respectively. High performance TFTs based on In2O3/Al2O3 were demonstrated, including an average field-effect mobility of 13 cm2 V−1 s−1, an on/off current ratio of ∼107, and a subthreshold swing of 0.18 V dec−1. Furthermore, the TFTs based on In2O3/Al2O3 prepared by the NTF process were successfully fabricated on PI substrates. The flexible TFT exhibits an ON voltage of close to 0 V and a subthreshold swing of 0.29 V dec−1. A device array with 4 × 5 units was fabricated and tested, confirming the excellent reproducibility of the flexible TFT. The electrical performance of the flexible TFT after bending cycles was investigated and excellent mechanical stability was demonstrated. The proposed NTF technology provides a promising approach for large-area and low-cost fabrication of flexible oxide electronic devices. [ABSTRACT FROM AUTHOR]

Brain-inspired neuromorphic computing has garnered significant attention for going beyond the constraint of von Neumann architecture. To emulate the human brain functions, various artificial synaptic devices have been proposed. Due to the high reliability and the CMOS compatibility, the synaptic transistors based on charge trapping (CT) mechanism have been considered to be one of the most promising candidates. However, most of the synaptic transistors based on CT mechanism were fabricated by costly vacuum-based techniques. In this report, based on a fully solution-driven strategy, the InZnO synaptic transistors, with Nd2O3 as the CT layer and ZrO2 as the dielectric layer, were integrated. The typical synaptic behaviors, including excitatory postsynaptic current, inhibitory postsynaptic current, memory enhancement, potentiation, and depression characteristics, were simulated by modulating presynaptic spikes. It is confirmed that the fabricated synaptic transistor shows low channel conductance and low energy consumption of 0.13 pJ per synaptic event. A recognition accuracy of 93.0% was achieved for the MNIST handwritten digital image dataset by an artificial neural network simulation. This study demonstrates the feasibility of solution-processed synaptic transistors, which exhibit significant potential for the neuromorphic applications. [ABSTRACT FROM AUTHOR]

The development of large-scale manufacturing and cost-saving artificial synaptic devices is of great significance for the realization of hardware neural networks. In this work, the In2O3 synaptic transistors with boron ion-doped ZrOx as the dielectric layer were fabricated by the solution process. The large counterclockwise hysteresis indicates that the nonvolatile memory capacity of the synaptic transistors was improved by boron ions doping. Typical synaptic functions including excitatory postsynaptic current, paired pulse facilitation, and high-pass filtering properties were simulated by applying gate bias. The multilevel channel conductance can be modulated by successive positive and negative pulses. Additionally, small nonlinearities were shown in the potentiation and depression processes, and high accuracies of 92.0% (small digits) and 93.8% (large digits) were obtained in digital recognition training. This study indicates that oxide-gated synaptic transistors based on the boron ions doping strategy show great potential for neuromorphic applications. [ABSTRACT FROM AUTHOR]

The g-C3N4/Ag/Bi2O2CO3 nanosheets were synthesized using a mixture of precursors containing melamine and nitrates of silver and bismuth through a simple one-pot synthesis strategy. In the presence of ammonium nitrate, g-C3N4/Ag/Bi2O2CO3 composite catalysts with different silver mass ratios were prepared, and the photodegradation performance of the composite samples was evaluated by photodegradation of tetracycline hydrochloride (TC) under simulated solar light irradiation. The synthesized composites were characterized by XPD, XPS, FT-IR, TEM, UV–vis DRS and PL. It was found that the g-C3N4/Ag/Bi2O2CO3 catalyst with Ag mass ratio of 4% exhibited the highest catalytic activity, and the degradation effect was more than 9 times that of pure C3N4 and nearly 5 times that of g-C3N4/Bi2O2CO3.In addition, cyclic experiments showed that g-C3N4/Ag/Bi2O2CO3 composites had certain stability. The photocatalytic performance of the g-C3N4/Ag/Bi2O2CO3 composites was attributable to the heterogeneous junction of Bi2O2CO3 and g-C3N4 and the surface plasmon resonance effect (SPR) of Ag nanoparticles. The energy levels of Bi2O2CO3 and g-C3N4 were properly matched to form a heterojunction, which promoted the separation and transfer of photogenerated electrons and holes, thereby improving the photocatalytic performance. The Ag surface plasmon resonance (SPR) effect not only accelerated the separation and transmission of electron–hole pairs, but also enhanced the absorption of visible light. Finally, based on the above basis, a possible photocatalytic mechanism was proposed. [ABSTRACT FROM AUTHOR]

Powdery mildew is a severe wheat disease that causes substantial yield losses in wheat production worldwide. The Chinese wheat landrace Changanhongmai (CAHM) exhibits high resistance to the physiological race E09 of powdery mildew. In this study, we characterized the powdery mildew resistance gene in CAHM, and developed molecular markers for wheat marker-assisted selection. To investigate the genetic characteristics of this resistant gene, we developed F1 plants, F2 generation population, and F2:3 families by crossing CAHM with SY225 (Shaanyou '225' as susceptible male parent). Genetic analysis demonstrated that all F1 plants were resistant to the disease, while the ratio of resistant to susceptible plants was 3: 1 in both the F2 population and F2:3 families, indicating that CAHM is inherited in a manner of a single dominant powdery mildew resistance gene, which was tentatively designated as PmCAHM. By using bulk segregation analysis, we constructed a genetic map encompassing Xgwm273, Xwmc626, Xgwm11, Xgwm18, Xgdm28, Xgpw7812, Xgpw5195, Xwmc694, and PmCAHM. Among these markers, Xgpw7812 and Xgpw5195 are flanking markers that are tightly linked to PmCAHM at a genetic distance of 2.5 cM and 8.4 cM, respectively. Furthermore, nullisomic-tetrasomic analysis revealed that PmCAHM is located on chromosome 1B. These results indicate that PmCAHM differs from the internationally recognized powdery mildew resistance genes in both location and source. In addition, a new germplasm/line NW1748 with stronger powdery mildew resistance and large grains was developed from the cross and backcross populations of Fengyou1718 (FY1718)/CAHM/5/FY 1718. Therefore, PmCAHM can serve as a novel powdery mildew resistance source for breeding of wheat by using NW1748 as the donor in the future. [ABSTRACT FROM AUTHOR]

Growth-factor-receptor-binding protein 2 (GRB2) is a non-enzymatic adaptor protein that plays a pivotal role in precisely regulated signaling cascades from cell surface receptors to cellular responses, including signaling transduction and gene expression. GRB2 binds to numerous target molecules, thereby modulating a complex cell signaling network with diverse functions. The structural characteristics of GRB2 are essential for its functionality, as its multiple domains and interaction mechanisms underpin its role in cellular biology. The typical signaling pathway involving GRB2 is initiated by the ligand stimulation to its receptor tyrosine kinases (RTKs). The activation of RTKs leads to the recruitment of GRB2 through its SH2 domain to the phosphorylated tyrosine residues on the receptor. GRB2, in turn, binds to the Son of Sevenless (SOS) protein through its SH3 domain. This binding facilitates the activation of Ras, a small GTPase, which triggers a cascade of downstream signaling events, ultimately leading to cell proliferation, survival, and differentiation. Further research and exploration into the structure and function of GRB2 hold great potential for providing novel insights and strategies to enhance medical approaches for related diseases. In this review, we provide an outline of the proteins that engage with domains of GRB2, along with the function of different GRB2 domains in governing cellular signaling pathways. This furnishes essential points of current studies for the forthcoming advancement of therapeutic medications aimed at GRB2. [ABSTRACT FROM AUTHOR]

[Ca.sup.2+] channel [beta]-subunit interactions with pore-forming [alpha]-subunits are long-thought to be obligatory for channel trafficking to the cell surface and for tuning of basal biophysical properties in many tissues. Unexpectedly, we demonstrate that transgenic expression of mutant [[alpha].sub.1C] subunits lacking capacity to bind [Ca.sub.V][beta] can traffic to the sarcolemma in adult cardiomyocytes in vivo and sustain normal excitation-contraction coupling. However, these [beta]-less [Ca.sup.2+] channels cannot be stimulated by [beta]-adrenergic pathway agonists, and thus adrenergic augmentation of contractility is markedly impaired in isolated cardiomyocytes and in hearts. Similarly, viral-mediated expression of a [beta]-subunit-sequestering peptide sharply curtailed [beta]-adrenergic stimulation of WT [Ca.sup.2+] channels, identifying an approach to specifically modulate [beta]-adrenergic regulation of cardiac contractility. Our data demonstrate that [beta] subunits are required for [beta]-adrenergic regulation of [Ca.sub.V]1.2 channels and positive inotropy in the heart, but are dispensable for [Ca.sub.V]1.2 trafficking to the adult cardiomyocyte cell surface, and for basal function and excitation-contraction coupling., Introduction In heart cells, [Ca.sup.2+] influx via [Ca.sub.V]1.2 channels mediates excitation-contraction (E-C) coupling, controls action potential duration, and regulates gene expression. [Ca.sub.V]1.2 channels are multi-subunit proteins composed minimally of a [...]

Novel Ag/Fe2O3/BiOI Z-scheme heterostructures are first fabricated through a facile hydrothermal method. The composition and properties of as-synthesized Ag/Fe2O3/BiOI nanocomposites are characterized by powder X-ray diffraction, scanning electron microscopy, high-resolution transmission electron microscopy, UV-Vis diffuse reflectance spectra, etc. The Ag/Fe2O3/BiOI systems exhibit remarkable degradation performance for tetracycline (TC). In particular, the composite (Ag/Fe2O3/BiOI-2) shows the highest efficiency when the contents of Ag and α-Fe2O3 are 2 wt% and 15%, respectively. The effects of operating parameters, including the solution pH, H2O2 concentration, TC concentration, and catalyst concentration, on the degradation efficiency are investigated. The photo-Fenton mechanism is studied, and the results indicated that •O2− is the main active specie for TC degradation. The enhanced performance of Ag/Fe2O3/BiOI heterostructures may be ascribed to the synergic effect between photocatalysis and the Fenton reaction. The formation of Ag/Fe2O3/BiOI heterojunction is beneficial to the transfer and separation of charge carriers. The photo-generated electrons accelerate the Fe2+/Fe3+ cycle and create the reductive reaction of H2O2. This research reveals that the Ag/Fe2O3/BiOI composite possesses great potential in wastewater treatment. [ABSTRACT FROM AUTHOR]

α-Synuclein (α-Syn) is a major biomarker of Parkinson's disease (PD). Concentration detection of α-Syn in cerebrospinal fluid and plasma of patients are used as a clue for early PD detection. Herein, we propose a thin-film transistor (TFT) biosensor based on an indium gallium zinc oxide (IGZO) thin film fabricated by the sol-gel method. The IGZO TFT biosensor is used for the early detection of PD after surface functionalization for α-Syn. The surface functionalization worked on the surface of the extended gate indium tin oxide sensing platform instead of the channel layer of TFT. Depending on concentrations of α-Syn in human cerebrospinal fluid and plasma, we diluted six different concentrations of α-Syn for detection, ranging from 1 pg ml−1 to 100 ng ml−1. The result shows that the biosensor exhibits high sensitivity and selectivity for α-Syn, a reliable sensing performance with a sensitivity of 189.9 mV dec−1, and a coefficient of determination R2 of 99.7% between 10 pg ml−1 and 100 ng ml−1. [ABSTRACT FROM AUTHOR]

In this work, In2O3 nanofibers were fabricated by electrospinning, and a field effect transistor (FET) based on In2O3 nanofibers was integrated. A hydroxyl-assisted strategy was proposed for both stability and performance enhancement for the FET. Hydrogen peroxide (H2O2) was added into a precursor solution for electrospinning. It is found that the stability of the FET is improved after H2O2 incorporation, while the mobility is decreased. Surprisingly, after UV irradiation, the FET with both high mobility and high stability was obtained. It is assumed that under UV irradiation, H2O2 is decomposed into highly reactive hydroxyl radicals (•OH), which contributes to the degradation of the polymer. XPS and FT-IR analysis verify that oxygen- and carbon-related defects can be removed through the hydroxyl-assistant strategy. Furthermore, the flexible FET based on In2O3 nanofibers with H2O2 addition and UV irradiation was fabricated on the PI substrate, and the high electrical performance is further demonstrated. This strategy makes it possible to fabricate the oxide nanofiber FET with both high mobility and high stability. [ABSTRACT FROM AUTHOR]

Electrolyte-gated synaptic transistors are promising for artificial neural morphological devices. However, few literatures have been reported regarding the manufacturing of electrolyte-gated synaptic transistors with low cost and biocompatible components. Here, the fully transparent synaptic transistors based on water-induced In2O3 thin films have been integrated by sol–gel method at low temperature, and lactose dissolved in citric acid solution is used as the gate electrolyte. The migration of the ions at the interface plays a crucial role in the potentiation and depression of the synaptic weight. In this work, the biological synaptic functions, including excitatory postsynaptic current, paired-pulse facilitation, high-pass filtering characteristics, short-term memory, and long-term memory, are mimicked. Meanwhile, based on the potentiation/depression behaviors of the synaptic transistor, a three-layer artificial neural network is applied for pattern recognition, and the recognition accuracy is as high as 94.6%. This study offers a possibility to realize fully transparent synaptic devices with biocompatible components at low temperature. [ABSTRACT FROM AUTHOR]

In this study, lanthanum-modified the shell–core magnetic nanocomposites with Fe3O4 core and homogeneous mesoporous silica shell (La-SBA-15@Fe3O4-x) were prepared. The preparation, morphology, composition and magnetic properties of La-SBA-15@Fe3O4 were investigated by TEM, SEM, XRD, VSM and BET. The results suggested that the SBA-15 have successfully encapsulated Fe3O4 and the magnetic particles were decorated by lanthanum. The adsorption experiments were carried out to explore effect of La-SBA-15@Fe3O4 on removal of phosphorus from aqueous solution. The kinetic study of adsorption process was investigated to describe the relationship between adsorption rate and adsorption equilibrium and the Langmuir and Freundlich isotherm models were employed to illustrate adsorption isotherm. [ABSTRACT FROM AUTHOR]

Emulating synaptic behavior using the three-terminal and ion-coupled transistors is considered as a promising strategy for the realization of neuromorphic devices. Meanwhile, one-dimensional (1-D) nanostructures show great potential for the fabrication of flexible electronic devices. In this work, 1-D indium oxide (In2O3) nanofibers were fabricated by the electrospinning (ES), and the flexible and compatible synaptic transistor based on In2O3 nanofibers was integrated on polyimide (PI) substrate. The synaptic behaviors, such as the short-term plasticity (STP) and long-term plasticity (LTP), are simulated by the synaptic transistor with chitosan solution as the gate dielectric. The fabricated synaptic transistor exhibits good biocompatibility and environmental compatibility, and the pattern recognition rate of the simulated device array by the Mixed National Institute of Standards and Technology (MNIST) database of the handwritten digits is confirmed to be as high as 92%. [ABSTRACT FROM AUTHOR]

Relative humidity (RH) in storage environment has a great impact on the electrical performance of thin film transistors (TFTs), and the RH is critical for semiconductor manufacturing and device packaging. In this work, solution-processed indium oxide (In2O3) TFT is fabricated, and the electrical performance of the device is investigated after being exposed to various RH conditions. It is found that the threshold voltage (Vth) and the mobility of In2O3 TFT exhibit clear responses to the RH ranging from 23% to 85%. The inherent mechanism about the humidity effect on the electrical performance is elaborated, and this is due to the "donor effect" from the absorbed water molecules. In addition to the effect on Vth and mobility, RH also exhibits a significant effect on the electrical stability of the TFT. The experimental result indicates that the In2O3 TFT exposed to RH <50% exhibits excellent stability with an applied positive bias stressing for 2000s. [ABSTRACT FROM AUTHOR]

Thin-film transistors (TFTs) with bilayer channels were used to improve the field-effect mobility and bias stress stability of the TFTs. Homogeneous structures were fabricated by the combination of a carrier deficient layer made of In2O3 thin film annealed in oxygen atmosphere (InO:O) and an electron injection layer made of In2O3 thin film annealed in air (InO:A). Compared with the InO:A/InO:A TFT with only air annealing, the field-effect mobility of InO:O/ InO:A TFT with two-step annealing process was improved from 0.04 to 5.11 cm2/Vs, the on/off current ratio was ameliorated from 4.6 × 105 to 7.6 × 107 A, while the VTH is decreased from 12.5 to 4.7 V under the positive bias stressing (PBS). It is confirmed that the excessive oxygen vacancies are produced by annealing the thin film in the air. The electrical performance of the InO:O/InO:A TFTs with two-step annealing process is greatly improved due to the formation of a low defect state and high carrier concentration electron transport layer, through the combination of the carrier transport layer and the carrier injection layer. These optimized electrical properties indicate an important step toward achieving transparent, high performance, and low-temperature metal oxides TFTs. [ABSTRACT FROM AUTHOR]

Large-conductance voltage- and calcium-activated potassium (BK) channels contain four pore-forming a subunits and four modulatory [beta] subunits. From the extents of disulfide cross-linking in channels on the cell surface between cysteine (Cys) substituted for residues in the first turns in the membrane of the SO transmembrane (TM) helix, unique to BK [alpha], and of the voltage-sensing domain TM helices S1-S4, we infer that SO is next to S3 and S4, but not to S1 and S2. Furthermore, of the two [beta]1 TM helices, TM2 is next to SO, and TM1 is next to TM2. Coexpression of [alpha] with two substituted Cys's, one in S0 and one in S2, and [beta]1 also with two substituted Cys's, one in TM1 and one in TM2, resulted in two as cross-linked by one [beta]. Thus, each [beta] lies between and can interact with the voltage-sensing domains of two adjacent [alpha] subunits. doi/ 10.1085/jgp.201010417

The cardiac-delayed rectifier [K.sup.+] current ([I.sub.KS]) is carried by a complex of KCNQ1 (Q1) subunits, containing the voltage-sensor domains and the pore, and auxiliary KCNE1 (E1) subunits, required for the characteristic [I.sub.KS] voltage dependence and kinetics. To locate the transmembrane helix of E1 (E1-TM) relative to the Q1 TM helices (S1-S6), we mutated, one at a time, the first four residues flanking the extracellular ends of S1-S6 and E1-TM to Cys, coexpressed all combinations of Q1 and E1 Cys-substituted mutants in CHO cells, and determined the extents of spontaneous disulfide-bond formation. Cys-flanking E1-TM readily formed disulfides with Cys-flanking S1 and S6, much less so with the S3-S4 linker, and not at all with S2 or S5. These results imply that the extracellular flank of the E1-TM is located between S1 and S6 on different subunits of Q1. The salient functional effects of selected cross-links were as follows. A disulfide from E1 K41C to S1 I145C strongly slowed deactivation, and one from E1 L42C to S6 V324C eliminated deactivation. Given that E1-TM is between S1 and S6 and that K41C and L42C are likely to point approximately oppositely, these two cross-links are likely to favor similar axial rotations of E1-TM. In the opposite orientation, a disulfide from E1 K41C to S6 V324C slightly slowed activation, and one from E1 L42C to S1 I145C slightly speeded deactivation. Thus, the first E1 orientation strongly favors the open state, while the approximately opposite orientation favors the closed state. arrhythmias | cardiac repolarization | electrophysiology | atrial fibrillation | S1

For field effect transistors (FETs) based on electrospun oxide nanofibers, the electrical stability can be deteriorated by high-temperature annealing treatment. In this work, the self-passivation of an In2O3 nanofiber FET is achieved by the consequent thermal treatment, water treatment, and deep ultraviolet (DUV) irradiation, and the FET is named as a TWD (thermal treatment-water treatment-DUV irradiation)-device. For comparison, the devices treated by thermal treatment and by thermal + water treatment were also fabricated and abbreviated as a T-device and a TW (thermal treatment-water treatment)-device, respectively. From the transfer characteristics of the T-, TW-, and TWD-devices, the electrical performance is first degraded by water treatment and then recovered after DUV irradiation. The positive bias stress test confirms the stability enhancement after TWD treatment, indicating the achievement of the self-passivated FET based on In2O3 nanofibers. The excellent electrical stability is owing to the structural relaxation and the removal of trap sites such as oxygen vacancy and hydroxide. Integrated with the high-k ZrO2 dielectric, the TWD-In2O3/ZrO2 FET exhibits further improved electrical performance, including a mobility of 3.35 cm2/V s and a high on/off current ratio of 107. [ABSTRACT FROM AUTHOR]