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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]

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]

[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 [...]