Parallel tuning of semi-dwarfism via differential splicing of Brachytic1 in commercial maize and smallholder sorghum.

In the current genomic era, the search and deployment of new semi-dwarf alleles have continued to develop better plant types in all cereals. We characterized an agronomically optimal semi-dwarf mutation in Zea mays L. and a parallel polymorphism in Sorghum bicolor L. We cloned the maize brachytic1 (br1-Mu) allele by a modified PCR-based Sequence Amplified Insertion Flanking Fragment (SAIFF) approach. Histology and RNA-Seq elucidated the mechanism of semi-dwarfism. GWAS linked a sorghum plant height QTL with the Br1 homolog by resequencing a West African sorghum landraces panel. The semi-dwarf br1-Mu allele encodes an MYB transcription factor78 that positively regulates stalk cell elongation by interacting with the polar auxin pathway. Semi-dwarfism is due to differential splicing and low functional Br1 wild-type transcript expression. The sorghum ortholog, SbBr1, co-segregates with the major plant height QTL qHT7.1 and is alternatively spliced. The high frequency of the Sbbr1 allele in African landraces suggests that African smallholder farmers used the semi-dwarf allele to improve plant height in sorghum long before efforts to introduce Green Revolution-style varieties in the 1960s. Surprisingly, variants for differential splicing of Brachytic1 were found in both commercial maize and smallholder sorghum, suggesting parallel tuning of plant architecture across these systems.

Controllable resistive switching behaviors in heteroepitaxial LaNiO3/Nb:SrTiO3Schottky junctions through oxygen vacancies engineering.

Perovskite oxide-based memristors have been extensively investigated for the application of non-volatile memories, and the oxygen vacancies associated with Schottky barrier changing are considered as the origin of the memristive behaviors. However, due to the difference of device fabrication progress, various resistive switching (RS) behaviors have been observed even in one device, deteriorating the stability and reproducibility of devices. Precisely controlling the oxygen vacancies distribution and shedding light on the behind physic mechanism of these RS behaviors, are highly desired to help improve the performance and stability of such Schottky junction-based memristors. In this work, the epitaxial LaNiO3(LNO)/Nb:SrTiO3(NSTO) is adopted to explore the influence of oxygen vacancy profiles on these abundant RS phenomena. It demonstrates that the migration of oxygen vacancy in LNO films plays a key role in memristive behaviors. When the effect of oxygen vacancies at the LNO/NSTO interface is negligible, improving the oxygen vacancies concentration in LNO film could facilitate resistance on/off ratio of HRS and LRS, and the corresponding conducting mechanisms attributes to the thermionic emission and tunneling-assisted thermionic emission, respectively. Moreover, it is found that reasonably increasing the oxygen vacancies at LNO/NSTO interface makes trap-assisted tunneling possible, also providing an effective way to improve the performance of the device. The results in this work have clearly elucidated the relationship between oxygen vacancy profile and RS behaviors, and give physical insights into the strategies for improving the device performance of Schottky junction-based memristors.

Building Fast Ion-Conducting Pathways on 3D Metallic Scaffolds for High-Performance Sodium Metal Anodes.

Building 3D electron-conducting scaffolds has been proven to be an effective way to alleviate severe dendritic growth and infinite volume change of sodium (Na) metal anodes. However, the electroplated Na metal cannot completely fill these scaffolds, especially at high current densities. Herein, we revealed that the uniform Na plating on 3D scaffolds is strongly related with the surface Na+ conductivity. As a proof of concept, we synthesized NiF2 hollow nanobowls grown on nickel foam (NiF2@NF) to realize homogeneous Na plating on the 3D scaffold. The NiF2 can be electrochemically converted to a NaF-enriched SEI layer, which significantly reduces the diffusion barrier for Na+ ions. The NaF-enriched SEI layer generated along the Ni backbones creates 3D interconnected ion-conducting pathways and allows for the rapid Na+ transfer throughout the entire 3D scaffold to enable densely filled and dendrite-free Na metal anodes. As a result, symmetric cells composed of identical Na/NiF2@NF electrodes show durable cycle life with an exceedingly stable voltage profile and small hysteresis, particularly at a high current density of 10 mA cm-2 or a large areal capacity of 10 mAh cm-2. Moreover, the full cell assembled with a Na3V2(PO4)3 cathode exhibits a superior capacity retention of 97.8% at a high current of 5C after 300 cycles.

Deciphering the phase transition-induced ultrahigh piezoresponse in (K,Na)NbO3-based piezoceramics.

Here, we introduce phase change mechanisms in lead-free piezoceramics as a strategy to utilize attendant volume change for harvesting large electrostrain. In the newly developed (K,Na)NbO3 solid-solution at the polymorphic phase boundary we combine atomic mapping of the local polar vector with in situ synchrotron X-ray diffraction and density functional theory to uncover the phase change and interpret its underlying nature. We demonstrate that an electric field-induced phase transition between orthorhombic and tetragonal phases triggers a dramatic volume change and contributes to a huge effective piezoelectric coefficient of 1250 pm V-1 along specific crystallographic directions. The existence of the phase transition is validated by a significant volume change evidenced by the simultaneous recording of macroscopic longitudinal and transverse strain. The principle of using phase transition to promote electrostrain provides broader design flexibility in the development of high-performance piezoelectric materials and opens the door for the discovery of high-performance future functional oxides.

Strain-induced yellow to blue emission tailoring of axial InGaN/GaN quantum wells in GaN nanorods synthesized by nanoimprint lithography.

GaN nanorods (NRds) with axial InGaN/GaN MQWs insertions are synthesized by an original cost-effective and large-scale nanoimprint-lithography process from an InGaN/GaN MQWs layer grown on c-sapphire substrates. By design, such NRds exhibit a single emission due to the c-axis MQWs. A systematic study of the emission of the NRds by time-resolved luminescence (TR-PL) and power dependence PL shows a diameter-controlled luminescence without significant degradation of the recombination rate thanks to the diameter-controlled strain tuning and QSCE. A blueshift up to 0.26 eV from 2.28 to 2.54 eV (543 nm to 488 nm) is observed for 3.2 nm thick InGaN/GaN QWs with an In composition of 19% when the NRds radius is reduced from 650 to 80 nm. The results are consistent with a 1-D based strain relaxation model. By combining state of the art knowledge of c-axis growth and the strong strain relieving capability of NRds, this process enables multiple and independent single-color emission from a single uniform InGaN/GaN MQWs layer in a single patterning step, then solving color mixing issue in InGaN based nanorods LED devices.

Ultra-rapid and highly efficient enrichment of organic pollutants via magnetic mesoporous nanosponge for ultrasensitive nanosensors.

Currently, owing to the single-molecule-level sensitivity and highly informative spectroscopic characteristics, surface-enhanced Raman scattering (SERS) is regarded as the most direct and effective detection technique. However, SERS still faces several challenges in its practical applications, such as the complex matrix interferences, and low sensitivity to the molecules of intrinsic small cross-sections or weak affinity to the surface of metals. Here, we show an enrichment-typed sensing strategy with both excellent selectivity and ultrahigh detection sensitivity based on a powerful porous composite material, called mesoporous nanosponge. The nanosponge consists of porous ß-cyclodextrin polymers immobilized with magnetic NPs, demonstrating remarkable capability of effective and fast removal of organic micropollutants, e.g., ~90% removal efficiency within ~1 min, and an enrichment factor up to ~103. By means of this current enrichment strategy, the limit of detection for typical organic pollutants can be significantly improved by 2~3 orders of magnitude. Consequently, the current enrichment strategy is proved to be applicable in a variety of fields for portable and fast detection, such as Raman and fluorescent sensing.

Enhanced effects and mechanisms of Syngonium podophyllum-Peperomia tetraphylla co-planting on phytoremediation of low concentration uranium-bearing wastewater.

To improve the remediation efficiency of plants on low concentration uranium-bearing wastewater and clarify its strengthening mechanism, Syngonium podophyllum-Peperomia tetraphylla co-planting system was established, the enhanced effects of plants interaction on uranium removal were investigated, the chemical forms, valence states, and subcellular distribution of uranium in plants were confirmed, and the mechanisms of alleviating uranium stress by plants interaction were revealed. In Syngonium podophyllum-Peperomia tetraphylla co-planting system, the total amount of ethanol-extracted uranium and deionized water-extracted uranium with higher toxicity in their roots were reduced by 10.30% and 7.17%, respectively, which reduced the toxicity of uranium to plants. Plants interaction can inhibit the reduction of U(VI) in the root of Peperomia tetraphylla, which is conducive to the transport of uranium from roots to shoots. In addition, uranium in plants mainly existed in the cell wall (54.44%-66.52%) and the soluble fraction (23.85%-32.89%). These results indicated that Syngonium podophyllum and Peperomia tetraphylla co-planting can enhance their effects of uranium removal by alleviating uranium stress with the cell wall immobilization and vacuole compartmentation, improving biomass of plants, increasing bioaccumulation factor and translocation factor of uranium.

The Clinical Effect of a Combination of Mouse Nerve Growth Factor and Methylcobalamin to Treat Lumbar Disc Herniation with Foot Drop: A Retrospective Cohort Study.

OBJECTIVE: To investigate the clinical effect of mouse nerve growth factor (mNGF) and methylcobalamin (MeCbl) for the treatment of lumbar disk herniation (LDH) with foot drop. METHODS: A total of 46 patients suffering from LDH with foot drop who underwent transforaminal lumbar interbody fusion (TLIF) surgery in our department from January 2015 to December 2017 were retrospectively analyzed. We divided these patients into two groups according to the different postoperative treatment which independently selected by patients after signing informed consent form: one group of 25 patients was treated with MeCbl alone (Group MeCbl), the other group of 21 patients was treated with a combination of mNGF and MeCbl (Group MeCbl+mNGF). Patient demographics, the visual analogue scale (VAS) scores, sensory and muscular strength improvement statistics at 1 week, 4 weeks, 12 weeks, and 12 months postoperatively were recorded. Motor/sensory deficits, sciatica and overall neurological outcome after treatment of MeCbl alone and combination of mNGF and MeCbl were retrospectively analyzed. RESULTS: The follow-up ranged between 12 and 42 months (mean 20.8 months). There were no significant differences between these two groups of patients with respect to sex ratio, age, smoking, diabetes, disease course, section of protruding disc(s), muscular strength of foot dorsiflexion or preoperative visual analogue scale (VAS) score (P > 0.05). The VAS scores of Group MeCbl+mNGF were significantly lower than Group MeCbl at 1 week, 4 weeks, 12 weeks, and 12 months postoperatively (4.32 ± 0.75 vs 5.25 ± 0.79,2.65 ± 0.48 vs 3.42 ± 0.52, 1.72 ± 0.36 vs 2.45 ± 0.39, 1.12 ± 0.22 vs 1.52 ± 0.24, P < 0.05). The effective rates of sensory improvement were significantly higher in Group MeCbl+mNGF compared with Group MeCbl at 12-week/12-month follow-up time point (90.48% vs 52.00%,95.24% vs 68.00%, P < 0.05). The effective rate of muscular strength improvement of the two groups did not differ significantly at 1 week after surgery but exhibited statistically significant differences at subsequent time points (61.90% vs 32.00%, 76.19% vs 44.00%, 80.95% vs 48.00%, P < 0.05). CONCLUSIONS: Application of mNGF had clinical effects on promoting the recovery of neurological function in patients suffering from LDH with foot drop.

Aspergillus niger changes the chemical form of uranium to decrease its biotoxicity, restricts its movement in plant and increase the growth of Syngonium podophyllum.

Aspergillus niger (A. niger) and Syngonium podophyllum (S. podophyllum) have been used for wastewater treatment, and have exhibited a promising application in recent years. To determine the effects of A. niger on uranium enrichment and uranium stress antagonism of S. podophyllum, the S. podophyllum-A. niger combined system was established, and hydroponic remediation experiments were carried out with uranium-containing wastewater. The results revealed that the bioaugmentation of A. niger could increase the biomass of S. podophyllum by 5-7%, reverse the process of U(VI) reduction induced by S. podophyllum, and increase the bioconcentration factor (BCF) and translocation factor (TF) of S. podophyllum to uranium by 35-41 and 0.01-0.06, respectively, thereby improving the reduction of uranium in wastewater. Moreover, A. niger could promote the cell wall immobilization and the subcellular compartmentalization of uranium in the root of S. podophyllum, reduce the phytotoxicity of uranium entering root cells, and inhibit the calcium efflux from root cells, thereby withdrawing the stress of uranium on S. podophyllum.

In vitro biocompatibility study of a water-rinsed biomimetic silk porous scaffold with olfactory ensheathing cells.

Olfactory ensheathing cells (OECs) are one of the most promising candidates for cell-based therapy in repairing spinal cord injury (SCI). However, the conventional method of transplanting OECs, orthotopically or intrathecally, leads to a low rate of cell replacement and limited utilization due to the impediments of chemical and physical barriers after SCI. In this study, we fabricated a three-dimensional (3-D) silk fibroin (SF) scaffold with a novel water-rinsing process. Compared to traditional methanol-treated scaffolds (MTS) and ethanol-treated scaffolds (ETS), the present water-rinsed scaffold (WRS) had a biomimetic nanofibrous structure and softer mechanical properties and was shown to be more biocompatible with OECs. The in vitro study showed that the 3-D SF scaffolds supported OEC adhesion and spreading and that the OECs had a normal cell phenotype. A quantitative study using the CCK8 assay revealed that OEC proliferation on the WRS was higher than that on the MTS and ETS. Moreover, a significantly higher level of GDNF was detected when the OECs were cultured on the WRS. Collectively, these results suggested that the 3-D biomimetic SF porous scaffolds not only provide suitable microenvironments for governing OEC behaviour but also serve as a promising transplantation strategy for OECs to repair SCI.

[Establishment of an animal model of Sparganum mansoni infection and study on therapeutic methods â Establishment of an animal model of Sparganum mansoni infection in mice and changes of serum specific antibody levels post-infection].

OBJECTIVE: To establish an animal model of Sparganum mansoni (plerocercoid larva of S. mansoni) infection in mice and observe the changes of blood routine examinations and serum anti-sparganum antibody levels after the infection. METHODS: The spargana tapeworms were collected from frogs, and 25 Kunming mice were orally infected with the Sparganum tapeworms (3 tapeworms/mouse). Two days before the infection and 2, 7, 14, 21, 28, 35, 42 days and 49 days after the infection, the peripheral blood samples of mice were collected for the blood routine examinations and the detections of anti-S. mansoni IgG antibody with ELISA. Forty-nine days after the infection, all the mice were sacrificed to find out the Sparganum tapeworms in the bodies of mice. RESULTS: The count of the total white blood cells was significantly elevated on the second day of the mice infected with Sparganum. The serum anti-Sparganum antibody was detected on the 14th day of the infection in some mice, and on the 21st day of the infection, the serum anti-Sparganum antibody was detected in all the mice. After the mice were sacrificed, the Sparganum tapeworms were found out in many tissues and organs, and especially in the subcutaneous tissues and muscle. CONCLUSIONS: The establishment of animal model of Sparganum infection is successful in mice with the oral method, and white blood cells and serum specific IgG antibody detection can be used as auxiliary diagnosis methods of S. mansoni infection.