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Grain size is an important determinant of grain weight and yield in rice. Although several genes related to grain size have been identified, natural variations in these genes that affect grain size are poorly characterized. Here, we describe the grain length QTL GL10, encoding MADS56, which positively regulates grain length and grain weight. A natural allelic variation of NIL-gl10, containing an ∼1.0-kb deletion in the first exon that abolishes its transcription, results in shorter grain length, lower grain weight and delayed flowering in gl10 plants. The knockout of GL10 in the HJX74 background leads to grain phenotypes similar to that of NIL-gl10, while overexpression of GL10 results in increased grain length and weight and earlier heading date. GL10 regulates grain length by promoting greater longitudinal cell growth in the grain glume. Additionally, GL10 participates in the regulation of gibberellic acid (GA) signaling pathway genes in young panicle tissues. Analysis of GL10 haplotypes shows obvious divergence between the japonica and indica lineages. Our findings reveal an allelic variation of GL10 that may explain differences in grain length among modern cultivars and could be used to breed rice varieties with optimized grain shape.

Paclobutrazol (PBZ) is a plant growth inhibitor and fungicide, but it is also carcinogenic and teratogenic, and has potential harm to human health. In this study, two PBZ haptens (PBZ-1, PBZ-2) were synthesized and conjugated with carrier proteins to get artificial antigens. A highly specific monoclonal antibody (mAb) against PBZ was prepared. The antibody subtype was IgG

We present extensive investigations of the crystallographic phase diagram and electronic properties of the Fe-based superconductor FeSe under extreme conditions (high pressure (HP) and low temperature (LT)) by synchrotron X-ray diffraction (XRD) and X-ray absorption spectroscopy (XAS). An isostructural phase transition (Tetragonal (T) →high-pressure Tetragonal (Tʹ)) is discovered in FeSe at ∼2.8 GPa based on the axial ratio c/a with finer pressure step as observed in Fe-As-based superconductor such as EuFe2As2. We also find a pressure-induced Tʹ → MnP-type phase transition at 7.6 GPa in FeSe, which is consistent with the documented pressure-induced high-spin → low-spin transition (∼6–7 GPa). These results reveal the pressure-induced structural phase transition sequence in FeSe at room temperature to be T → Tʹ → Tʹ+MnP-type at pressures of 0–10.6 GPa, enriching the crystallographic phase diagram. The HPLT XRD data also indicate that a sluggish structural phase transition (Cmma → Pnma) begins at 7.5 GPa, and these two phases coexist up to 26.5 GPa. The HP X-ray absorption near-edge spectroscopy (XANES) measurement shows that Eo of Se experiences a pressure-induced shift to high energy, evidencing strongly charge transfer between Fe and Se under high pressure. Our results shed lights on the correlation between crystallographic/electronic structure and superconductivity in this material.

Nanocrystalline tin(IV) sulfide (SnS 2 ) with diverse morphologies were controllably synthesized using organic additives, such as cetyltrimethylammonium bromide (C 16 TAB), sodium dodecyl sulfate (SDS), p -benzenedicarboxylic acid in ethanol solution under mild reaction conditions. By adjusting the type and concentration of the organic additives, different nanostructured SnS 2 were prepared including flower-like, fiber-, layer-rolled and sheet-like forms. Some other factors on the morphology, size and crystallization of the prepared SnS 2 nanostructures were also investigated, including reaction time and temperature. Various techniques were applied to characterize the prepared SnS 2 nanostructures including X-ray diffraction, Transmission Electron Microscopy and UV–Vis spectroscopy. The trace water or hydration water of SnCl 4 ·5H 2 O brings no impurities in ethanol solution despite tin(IV) ions are easy to hydrolyze, and the pure-phase SnS 2 can be synthesized successfully. Thermogravimetric analysis (TGA) shows that the amount of the passivated additive C 16 TAB molecule within SnS 2 is about 6.4 wt.% when the initial molar ratio of C 16 TAB to Sn 4+ is 1:1. This method avoids hydrolyzing and expands the application range of tin salts containing hydration water in synthesizing pure-phase nanocrystalline tin(IV) sulfide.

Hydrophobic polyolefin (PO) surfaces were prepared by perfluoropolyether (PFPE) blending and nanostructuring. Surface modifications were done by injection molding. Two high-density polyethylenes and polypropylene were melt blended with 2.0 wt.% of PFPE. Both polyethylenes formed blends with PFPE and showed improved hydrophobicity. For nanostructuring, self-ordered nanoporous mold inserts were fabricated by anodizing aluminum in polyprotic acid. Nanostructured samples were prepared with nanoporous anodic aluminum oxide masks from pure polyolefins and from PO/PFPE blends containing 2 wt.% PFPE. Nanostructuring had a marked effect on the contact angle between injection moldable polyolefins and water: well-arranged, high aspect ratio nanostructure was found over the entire surface.

Anodic aluminum oxide templates containing extended arrays of holes with ∼30-nm diameter and approximately 128-nm spacing were sputter-coated with Nb. We find pronounced matching effects in the transport and magnetization measurements beyond 4 kOe. In addition, we observe Little–Parks oscillations of the superconducting critical temperature. We compare the flux pinning in the patterned samples to unpatterned reference samples and find a significant enhancement of the critical current.

Nb films containing extended arrays of holes with 45-nm diameter and 100-nm spacing have been fabricated using anodized aluminum oxide as substrate. Pronounced matching effects in the magnetization are seen in fields up to 9 kOe . Flux pinning in the patterned samples is enhanced by two orders of magnitude as compared to unpatterned reference samples in applied fields exceeding 5 kOe . The matching effects are a dominant contribution to vortex pinning at temperatures as low as 4.2 K due to the nano-scale spacing of the holes.

By measuring the critical current at current ramping rate of 2×10−5 A/s to 5×102 A/s we find that at a fixed temperature and magnetic field the critical current in pure 2H-NbSe2 increases with increasing current ramping rate. These experiments show that metastable states, which are missed in the usual transport measurements, do exist in the field cooled vortex lattice. We also show that the fast transport technique provides a means of probing the initial vortex lattice.

Recent studies have shown a number of surprising vortex dynamics phenomena which include: low frequency noise, slow voltage oscillations, history dependent dynamic response, memory of the direction, amplitude, and frequency of the previously applied current, suppression of the ac response by a small dc bias, and a strong frequency dependence. These phenomena are incompatible with the current understanding of bulk vortex dynamics. We propose a generic mechanism in terms of the competition between the injection of a disordered vortex phase through the surface barriers, and the annealing of this metastable disorder by the transport current. The model is confirmed by investigating the current distribution across 2H-NbSe 2 crystals using arrays of Hall sensors.

Oriented (Hg 0.7 Mo 0.3 )Sr 2 (Ca 0.7 Y 0.3 )Cu 2 O x and (Hg 0.9 Re 0.1 )Ba 2 CaCu 2 O y superconducting films were prepared on SrTiO 3 substrates using laser ablation and post-Hg-vapor annealing. Due to the stability of Mo 0.3 Sr 2 (Ca 0.7 Y 0.3 )Cu 2 O x and Re 0.1 Ba 2 CaCu 2 O y in air, no special handling was needed during the grinding, mixing and pressing of the precursor targets. The superconductivity of the films was characterized with the temperature dependence of the ac susceptibility ( χ - T ) and the resistance ( R - T ) while the crystallography was probed with x-ray diffraction (XRD) and scanning electron microscopy (SEM).

We investigated current–voltage curves of Bi 2 Sr 2 CaCu 2 O 8 and YBa 2 Cu 3 O 7 thin films. Voltage jumps due to flux-flow instabilities at high vortex-velocities were found and interpreted in the framework of the theory of Larkin and Ovchinnikov. The extensions introduced by Bezuglyj et al. account for quasiparticle heating during the measurement. While in Bi 2 Sr 2 CaCu 2 O 8 the instability is found in the vortex-liquid phase, in YBa 2 Cu 3 O 7 we observed it in the vortex-glass phase. Moreover, we studied the temporal behavior of the instability in current–voltage curves with a time resolution in the microsecond range.

We have investigated the microstructure and compositional distribution of the Y1Ba2Cu3O7−x superconductor with scanning electron microscopy, energy dispersive X-ray spectrometry and X-ray diffraction. It has been found that the microregion compositions are far from the ideal composition. This is especially due to the yttrium content which is higher than the expected amount in the interfacial region between crystalline grains.