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Ultraviolet photodetectors have aroused wide concern based on wide-band-gap semiconductors, such as GaN and Ga2O3. Exploiting multi-spectral detection provides unparalleled driving force and direction for high-precision ultraviolet detection. Here we demonstrate an optimized design strategy of Ga2O3/GaN heterostructure bi-color ultraviolet photodetector, which presents extremely high responsivity and UV-to-visible rejection ratio. The electric field distribution of optical absorption region was profitably modified by optimizing heterostructure doping concentration and thickness ratio, thus further facilitating the separation and transport of photogenerated carriers. Meanwhile, the modulation of Ga2O3/GaN heterostructure band offset leads to the fluent transport of electrons and the blocking of holes, thereby enhancing the photoconductive gain of the device. Eventually, the Ga2O3/GaN heterostructure photodetector successfully realizes dual-band ultraviolet detection and achieves high responsivity of 892/950 A/W at the wavelength of 254/365 nm, respectively. Moreover, UV-to-visible rejection ratio of the optimized device also keeps at a high level (∼103) while exhibiting dual-band characteristic. The proposed optimization scheme is anticipated to provide significant guidance for the reasonable device fabrication and design on multi-spectral detection.

The phase reduction approach has manifested its power in analyzing the rhythmic behaviors for limit cycle oscillators. For coherent oscillation purely induced by noise, e.g., the coherence resonance oscillator, the stochastic dynamics exhibit almost deterministic limit cycle phenomenon which inspires the application of the phase reduction approach to this kind of systems. In this paper, the FitzHugh–Nagumo system in coherence resonance is modeled as a jump process. The phase sensitivity is obtained by applying the phase reduction approach for the hybrid system. A modified direct method is proposed to compare the theoretical results with those of Monte Carlo simulation for the stochastic system, which shows a relatively good agreement for the perturbation not being too small. The phase reduction results of the coherent oscillators are applied to two coupled FitzHugh–Nagumo neurons. It is interesting that the phase difference of the coupled coherent oscillators does not converge as the deterministic oscillators, but forms a distribution where the peaks and valleys correspond to the stable and unstable synchronizations predicted by the phase coupling functions. The idea in this paper could be applied to other coherent oscillators where the stochastic dynamics follow almost deterministic paths.

The next-generation hybrid seed technology enables the successful production of sortable hybrid seeds from genic male sterile (GMS) lines and maintainers; however, it requires multiple laborious and complicated steps. Here, we designed a simple next-generation hybrid seed production strategy that takes advantage of the CRISPR/Cas9 technology to create a Manipulated GMS Maintainer (MGM) system via a single transformation. Under this schema, the maize male fertility gene ZmMS26 was nullified by removal of its fifth exon using the CRISPR/Cas9 system on a vector, and a second vector carrying a functional ZmMS26 cDNA was co-transformed to restore fertility. The second vector also contains a male gametophyte inactivation gene (ZmAA1) encoding maize α-amylase driven by the pollen-specific promoter PG47 and an endosperm fluorescent marker (DsRED) driven by the barley endosperm aleurone-specific promoter Ltp2. The derived single-copy hemizygous MGM lines bore a mutated MS26 gene, leading to complete male sterility but normal vegetative growth and grain yield. The MGM system could prevent genetic transmission of the MGM elements via male gametophytes, providing an efficient method for sorting maintainer seeds labeled by DsRED. This strategy can be extended to any GMS gene and to hybrid crops other than maize.

Single-nucleotide polymorphisms contribute to phenotypic diversity in maize. Creation and functional annotation of point mutations has been limited by the low efficiency of conventional methods based on random mutation. An efficient tool for generating targeted single-base mutations is desirable for both functional genomics and precise genetic improvement. The objective of this study was to test the efficiency of targeted C-to-T base editing of two non-allelic acetolactate synthase (ALS) in generating sulfonylurea herbicide-resistant mutants. A CRISPR/Cas9 nickase-cytidine deaminase fused with uracil DNA glycosylase inhibitor (UGI) was employed to achieve targeted conversion of cytosine to thymine in ZmALS1 and ZmALS2. Both protoplasts and recovered mutant plants showed the activity of the cytosine base editor, with an in vivo efficiency of up to 13.8%. Transgene-free edited plants harboring a homozygous ZmALS1 mutation or a ZmALS1 and ZmALS2 double mutation were tested for their resistance at a dose of up to 15-fold the recommended limit of chlorsulfuron, a sulfonylurea herbicide widely used in agriculture. Targeted base editing of C-to-T per se and a phenotype verified in the generated mutants demonstrates the power of base editing in precise maize breeding.

Improvement of water quality has frequently been delayed due to high recycling rates of nutrients across the sediment–water interface in a reservoir. Diffusive fluxes and annual loads of ammonia nitrogen (NH4+-N) and phosphate (PO43−-P) in sediments from Guanting Reservoir (GTR) were estimated according to their vertical distribution. The average contents of NH4+-N and PO43−-P in surface pore water were higher by factors of 6.9 – 11.7 and 1.3 – 6.4 than those in overlying water, respectively. The ranges of fluxes were 1.59 – 13.0 (mg m2 d−1) for NH4+-N, and 0.002 – 0.196 (mg m2 d−1) for PO43−-P. The annual load contributions from sediments of GTR were 659 t a−1 for NH4+-N and 4.83 t a−1 for PO43−-P. Notably, the upstream of GTR accounted for 50.7% annual loads for NH4+-N, while the downstream contributed 71.2% loads to PO43−-P. This study will better inform future environmental management for the reservoir.

Establishing a rapid, accurate, high-throughput and easily implementable genotyping method is highly desirable for functional genomics, genetic improvement and mutant screening. Here, we describe a convenient and inexpensive technique for genotyping using the targeted DNA endonuclease activity of Cas9 or Cas9NG ribonucleoproteins complex (sgRNA/Cas9-RNP or sgRNA/Cas9NG-RNP). In this study, Cas9 and Cas9NG protein purified from E. coli extract was assembled with in vitro transcribed single guide RNA (sgRNA)or enhanced sgRNA (esgRNA) as an assembled ribonucleoprotein (RNP) complex to fulfill the targeted endonuclease activity on the PCR amplicons of ZmWx exon 7. The restriction profiles can be converted into genotyping results of wildtype, homozygous or heterozygous mutant, respectively. Our data showed that ZmWx gene-edited mutants can be genotyped rapidly and efficiently by the sgRNA-optimized system esgRNA/Cas9. The reaction component optimization data suggested that 500 ng of DNA substrates could be cleavaged completely by incubating with 1 µg 1:1 molar ratio of esgRNA/Cas9 ribonucleoproteins for 30 minutes at 37°C, or by 4 µg 1:1 molar ratio of esgRNA/Cas9NG ribonucleoproteins for 4 hours at 37°C. Expanding the targeting flexibility of mutant detection via esgRNA/Cas9NG indicated that Cas9NG variant might recognize relax NG PAM (protospacer-adjacent-motif, PAM) at the expense of decreasing restriction activity, which is necessary to improve the activity of esgRNA/Cas9NG by further optimization. Therefore, the establishment and application of esgRNA/Cas9 based PCR/RNP technique provides an easy, simple and low-cost approach to genotyping in functional genomics, molecular breeding and mutant screening. In addition, our in vitro data on esgRNA/Cas9NG has certain and significant reference value for developing it into in vivo genome editing studies.

Clustered regularly interspaced short palindromic repeats (CRISPR)-Cas systems can be engineered as programmable transcription factors to either activate (CRISPRa) or inhibit transcription. Apomixis is extremely valuable for the seed industry in breeding clonal seeds with pure genetic backgrounds. We report here a CRISPR/dCas9-based toolkit equipped with dCas9-VP64 and MS2-p65-HSF1 effectors that may specifically target genes with high activation capability. We explored the application of in vivo CRISPRa targeting of maize BABY BOOM2 (ZmBBM2), acting as a fertilization checkpoint, as a means to engineer parthenogenesis. We detected ZmBBM2 transcripts only in egg cells but not in other maternal gametic cells. Activation of ZmBBM2 in egg cells in vivo caused maternal cell-autonomous parthenogenesis to produce haploid seeds. Our work provides a highly specific gene-activation CRISPRa technology for target cells and verifies its application for parthenogenesis induction in maize.

Low-density polyethylene (LDPE) has been widely used as a sorbent for passive sampling of hydrophobic organic contaminants (HOCs) in aquatic environments. However, it has seen only limited application in passive sampling for measurement of freely dissolved concentrations of parent and substituted PAHs (SPAHs), which are known to be toxic, mutagenic and carcinogenic. Here, the 16 priority PAHs and some typical PAHs were selected as target compounds and were simultaneously determined by gas chromatography–mass spectrometer (GC–MS). Some batch experiments were conducted in the laboratory to explore the adsorption kinetics of the target compounds in LDPE membranes. The results showed that both PAHs and SPAHs could reach equilibrium status within 19–38 days in sorption kinetic experiments. The coefficients of partitioning between LDPE film (50 μm thickness) and water (KLDPE) for the 16 priority PAHs were in good agreement with previously reported values, and the values of KLDPE for the 9 SPAHs are reported in this study for the first time. Significant linear relationships were observed, i.e., log KLDPE = 0.705 × log KOW + 1.534 for PAHs (R2 = 0.8361, p

Traditional wired monitoring systems exhibit huge limitations in blast wave monitoring. To meet the requirements of long range, low cost, weight reduction, increased ease of installation maintenance, and big-data transmission in blast wave monitoring, a new distributed linear-spatial-array (D-LSA) sensing system based on low-power wide-area network (LPWAN) is proposed in this paper. This approach adopts a multichannel LoRa and NB-IoT air-blast gateway (M-CLNAG) and multiple FPGA-based wireless pressure LoRa nodes (FWPLNs) to construct a large-scale LPWAN for blast wave monitoring. The empirical models of dynamic parameter calculation (peak overpressure, duration of the positive phase and impulse) on the basis of D-LSA sensing system are redesigned for blast wave monitoring as well. Furthermore, we have evaluated the errors between the measured data from D-LSA sensing system and data from the redesigned empirical models. Finally, the wireless quality performance in terms of received signal strength indication (RSSI) and packet receive rate (PDR) for blast wave monitoring is also verified. This paper is conducted to provide new insights into how a sensing system integrating with LPWAN is designed in blast wave monitoring for acquiring dynamic parameters accurately and carrying out remote network communication efficiently, and further opening a door for wireless sensor network (WSN) in more blast wave monitoring scenarios.

This research aimed to study the influence of principal–teacher management communication on teachers’ psychological empowerment, affective commitment, job performance, and the role that psychological empowerment and affective commitment plays in principal–teacher management communication and teacher performance. The participants were 868 teachers in primary and secondary schools in Beijing, Hubei, and other provinces in China. SEM was used to examine the mediating role of psychological empowerment and affective commitment. The study found that principal–teacher management communication can significantly predict teachers’ psychological empowerment, affective commitment. In addition, psychological empowerment and affective commitment partially mediate managerial communication and teacher performance.

Free-field shock wave (FSW) in explosion monitored by electrical wired system with piezoelectric pressure probe sensor (PPPS) has been widely investigated and applied. However, it is very difficult to accomplish accurate pressure measurement for shock wave (SW) due to steep rising edge, short pulse width characteristics of peak pressure signal and different incident angle of SW to sensor. This paper aims to find an approach to integrate the mounting structure with PPPS for the FSW testing more accurately. First, we design two mounting structures namely disc structure and wedge structure for sensor installation and evaluate the impacts of different incident angles of SW on PPPS under two installation structures by simulation. Furthermore, the pressure signals are obtained by two measurement system relying on commercial PPPSs from PCB and Kistler Co., Ltd., respectively, and we reconstruct the overpressure waveform by wired measurement system. The results from the experiment demonstrate that the reconstructed waveforms have good uniformities. Depending on the simulation model and experiment data, this paper is conducted to provide new insights and approach into how the integration of mounting structure and PPPS is implemented for acquiring dynamic parameters accurately, and further giving advisable reference to various sensors and structures applied in more FSW monitoring scenarios.

The path from resting to spiking threshold can generate a typical action potential in neurons. For excitable systems with ubiquitous noise, this process can be investigated in the framework of large deviation theory. In this paper, a special position (named as excitability inflection point) of the exit process in the canonical Class 1 excitable system is identified, which is both the extremal position of the dispersion and the momentum. The role of this point is examined by adding a Gaussian white noise and a pulse with a special position into the deterministic system. Surprisingly, by calculating the firing rate, its extremal position can be made closer to the theoretical excitability inflection point with vanishing pulse instead of vanishing noise. The influences of finite noise and pulse are investigated in detail by fixing one of them and changing the other. They showed distinct impacts on the real extremal positions of the firing rate. Finally, some open problems are given.

This study investigates the mediating role of teachers’ psychological empowerment and the moderating role of team psychological safety in the relationship between empowering leadership and teachers’ innovative behavior in teaching and research groups (TR groups) as professional learning communities. In total, 507 teachers from 114 TR groups in China participated in this study. The multilevel model results show that empowering leadership improves teachers’ innovative behavior by increasing teachers’ psychological empowerment, which is not influenced by team psychological safety. A supplementary analysis shows that the relationship between team psychological safety and teachers’ innovative behavior is also mediated by psychological empowerment.

Algal blooms bring massive amounts of algal organic matter (AOM) into eutrophic lakes, which influences microbial methylmercury (MeHg) production. However, because of the complexity of AOM and its dynamic changes during algal decomposition, the relationship between AOM and microbial Hg methylators remains poorly understood, which hinders predicting MeHg production and its bioaccumulation in eutrophic shallow lakes. To address that, we explored the impacts of AOM on microbial Hg methylators and MeHg production by characterizing dissolved organic matter with Fourier transform ion cyclotron resonance mass spectrometry (FTICR-MS) and three-dimensional excitation-emission matrix (3D-EEM) fluorescence spectroscopy and quantifying the microbial Hg methylation gene hgcA. We first reveal that the predominance of methanogens, facilitated by eutrophication-induced carbon input, could drive MeHg production in lake water. Specifically, bioavailable components of AOM (i.e., CHONs such as aromatic proteins and soluble microbial byproduct-like materials) increased the abundances (Archaea-hgcA gene: 438-2240% higher) and activities (net CH4 production: 16.0-44.4% higher) of Archaea (e.g., methanogens). These in turn led to enhanced dissolved MeHg levels (24.3-15,918% higher) for three major eutrophic shallow lakes in China. Nevertheless, our model results indicate that AOM-facilitated MeHg production could be offset by AOM-induced MeHg biodilution under eutrophication. Our study would help reduce uncertainties in predicting MeHg production, providing a basis for mitigating the MeHg risk in eutrophic lakes.

Noise is ubiquitous and has been verified to play constructive roles in various systems, among which the inverse stochastic resonance (ISR) has aroused much attention in contrast to positive effects such as stochastic resonance. The ISR has been observed in both bistable and monostable systems for which the mechanisms are revealed as noise-induced biased switching and noise-enhanced stability, respectively. In this paper, we investigate the ISR phenomenon in the monostable and bistable Hindmarsh–Rose neurons within a unified framework of large deviation theory. The critical noise strengths for both cases can be obtained by matching the timescales between noise-induced boundary crossing and the limit cycle. Furthermore, different stages of ISR are revealed by the bursting frequency distribution, where the gradual increase of the peak bursting frequency can also be explained within the same framework. The perspective and results in this paper may shed some light on the understanding of the noise-induced complex phenomena in stochastic dynamical systems.

Genome editing by clustered regularly interspaced short palindromic sequences (CRISPR)/CRISPR-associated protein 9 (Cas9) has revolutionized functional gene analysis and genetic improvement. While reporter-assisted CRISPR/Cas systems can greatly facilitate the selection of genome-edited plants produced via stable transformation, this approach has not been well established in seed crops. Here, we established the seed fluorescence reporter (SFR)-assisted CRISPR/Cas9 systems in maize (Zea mays L.), using the red fluorescent DsRED protein expressed in the endosperm (En-SFR/Cas9), embryos (Em-SFR/Cas9), or both tissues (Em/En-SFR/Cas9). All three SFRs showed distinct fluorescent patterns in the seed endosperm and embryo that allowed the selection of seeds carrying the transgene of having segregated the transgene out. We describe several case studies of the implementation of En-SFR/Cas9, Em-SFR/Cas9, and Em/En- SFR/Cas9 to identify plants not harboring the genome-editing cassette but carrying the desired mutations at target genes in single genes or in small-scale mutant libraries, and report on the successful generation of single-target mutants and/or mutant libraries with En-SFR/Cas9, Em-SFR/Cas9, and Em/En-SFR/Cas9. SFR-assisted genome editing may have particular value for application scenarios with a low transformation frequency and may be extended to other important monocot seed crops.

Phase reduction approach is a useful tool to reduce the dimension of limit-cycle oscillators. In this paper, it is applied to the FitzHugh-Nagumo neuron model with large timescale separation. To quantitate the response of the oscillator to the external perturbations, the asymptotic behaviors of the phase sensitivity functions for fast and slow variables are obtained. It is shown that in the relaxation limit, apart from the jump points which are the vertices of the cubic nullcline, the phase is insensitive to the perturbations on the fast variable. By using the phase sensitivity functions, two cases, namely, periodic pulse train perturbation and common noise perturbation, are investigated. Theoretical and numerical results suggest better performance for the synchronization behaviors of the perturbations on the slow variable for large timescale separation.

Tunneling field-effect transistors (TFETs) based on two-dimensional (2D) materials are expected to break the physical limits of Moore's Law and extend them to the sub-10 nm scope. We systematically study the performance limits of sub-10 nm (6.4-9.6 nm) monolayer (ML) AsP TFETs by means of ab initio quantum transport calculation. With optimized doping, ML AsP TFETs show excellent performance in the armchair transport direction, which is satisfied the requirements of the International Technology Roadmap for Semiconductors (ITRS) and the International Roadmap for Devices and Systems (IRDS 2028 projection) for high-performance (HP) applications in the next ten years in terms of on-state current, delay time, and power consumption per wide power. More encouragingly, ML AsP TFET can still meet the goal of ITRS for low-power (LP) applications even if the gate length is scaled down to 8.7 nm. The on-state current of our proposed AsP TFET is superior to that of TFETs based on InAs, arsenene, antimonene, bismuthene, etc at approximate nodes, making it highly competitive in two-dimensional material semiconductor devices.

The exit problem in the framework of the large deviation theory has been a hot topic in the past few decades. The most probable escape path in the weak-noise limit has been clarified by the Freidlin–Wentzell action functional. However, noise in real physical systems cannot be arbitrarily small while noise with finite strength may induce nontrivial phenomena, such as noise-induced shift and noise-induced saddle-point avoidance. Traditional Monte Carlo simulation of noise-induced escape will take exponentially large time as noise approaches zero. The majority of the time is wasted on the uninteresting wandering around the attractors. In this paper, a new method is proposed to decrease the escape simulation time by an exponentially large factor by introducing a series of interfaces and by applying the reinjection on them. This method can be used to calculate the exit location distribution. It is verified by examining two classical examples and is compared with theoretical predictions. The results show that the method performs well for weak noise while may induce certain deviations for large noise. Finally, some possible ways to improve our method are discussed.

In the present paper, a simple spike timing distance is defined which can be used to measure the degree of synchronization with the information only encoded in the precise timing of the spike trains. Via calculating the spike timing distance defined in this paper, the spike train similarity of uncoupled Hindmarsh–Rose neurons in bursting or spiking states with different initial conditions is investigated and the results are compared with other spike train distance measures. Later, the spike timing distance measure is applied to study the synchronization of coupled or common noise-stimulated neurons. Counterintuitively, the addition of weak coupling or common noise doesn’t enhance the degree of synchronization although after critical values, both of them can induce complete synchronizations. More interestingly, the common noise plays opposite roles for weak and strong enough couplings. Finally, it should be noted that the measure defined in this paper can be extended to measure large neuronal ensembles and the lag synchronization.

In this study, we report three cases of sporadic Creutzfeldt–Jakob disease in China, two confirmed cases and one probable case. The aim of this study was to enrich the data regarding clinical and epidemiological features of this disease and to provide reference for the diagnosis, control, and prevention of sporadic Creutzfeldt–Jakob disease.

Genome editing is a genetic engineering technique that uses site-directed cleavage activity of specific artificial nucleases and endogenous DNA damage repair activity to generate insertions, deletions or substitutions in the targeted genomic loci. As the accuracy and efficiency of genome editing is improving and the operation is simple, the application of genome editing is expanding. This article provides an overview of the three major genome editing technologies and genome editing types, and the regulatory frameworks for genome-edited products were summarized in the United States, the European Union, and other countries. At the same time, based on the Chinese safety management principles and systems for genetically modified organisms (GMOs), the authors proposed a regulatory framework for genome-edited products. Genome-edited products should first be classified according to whether containing exogenous genetic components such as Cas9 editing enzymes or not. They should be regulated as traditional genetically modified organisms if they do. Otherwise, the regulation of genome-edited products depends on targeted modifications.基因组编辑技术是指利用特异性核酸酶的定点剪切活性与细胞内源DNA 损伤修复活性，在基因组水平上对目的核酸序列或单个核苷酸进行定点修饰的基因工程技术，该技术可以对生物体基因组进行精确敲除、插入、单碱基突变或置换等编辑。目前，基因组编辑技术具有精确性、高效性及易操作性，应用范围日益扩大。文中简要概述了3 种主要的基因组编辑技术工具及基因组编辑类型，介绍了美国、欧盟等国家和地区对基因组编辑产品的监管体制。同时，基于我国对转基因产品的安全管理原则与体系，初步提出了基因组编辑产品的安全管理思路。根据中间材料或产品中是否含有外源编辑酶蛋白基因成分对基因组编辑产品进行分类管理，含有外源编辑酶的材料应按现有转基因安全管理办法进行管理；中间材料或产品中不含有Cas9 等编辑酶的材料应根据被编辑位点的特征进行具体分类管理。.

Water transport from roots to leaves through xylem is important for plant growth and development. Defects in water transport can cause drought stress, even when there is adequate water in the soil. Here, we identified the maize (Zea mays) wilty5 (wi5) mutant, which exhibits marked dwarfing and leaf wilting throughout most of its life cycle under normal growth conditions. wilty5 seedlings exhibited lower xylem conductivity and wilted more rapidly under drought, NaCl, and high temperature treatments than wild‐type plants. Map‐based cloning revealed that WI5 encodes an active endo‐1,4‐β‐xylanase from glycosyl dehydration family 10, which mainly functions in degrading and reorganizing cell wall xylan. Reverse‐transcription polymerase chain reaction and β‐glucuronidase assays revealed that WI5 is highly expressed in stems, especially in internodes undergoing secondary wall assembly. RNA sequencing suggested that WI5 plays a unique role in internode growth. Immunohistochemistry and electron microscopy confirmed that wi5 is defective in xylan deposition and secondary cell wall thickening. Lignin deposition and xylan content were markedly reduced in wi5 compared to the wild‐type plants. Our results suggest that WI5 functions in xylem cell wall thickening through its xylanase activity and thereby regulates xylem water transport, the drought stress response, and plant growth in maize., In this study, we report a endo‐1,4‐β‐xylanase WI5 in maize, which is important for secondary cell wall thickening and water transport in elongating internodes.

Low-density polyethylene (LDPE) has been widely used as a sorbent for passive sampling of hydrophobic organic contaminants (HOCs) in aquatic environments. However, it has seen only limited application in passive sampling for measurement of freely dissolved concentrations of parent and substituted PAHs (SPAHs), which are known to be toxic, mutagenic and carcinogenic. Here, the 16 priority PAHs and some typical PAHs were selected as target compounds and were simultaneously determined by gas chromatography-mass spectrometer (GC-MS). Some batch experiments were conducted in the laboratory to explore the adsorption kinetics of the target compounds in LDPE membranes. The results showed that both PAHs and SPAHs could reach equilibrium status within 19-38 days in sorption kinetic experiments. The coefficients of partitioning between LDPE film (50 μm thickness) and water (K

X-ray-induced photodynamic therapy (X-PDT) combines both the advantages of radiotherapy (RT) and PDT, and has considerable potential applications in clinical deep-penetrating cancer therapy. However, it is still a major challenge to prepare monodisperse nanoscintillators with uniform size and high light yield. In this study, a general and rapid synthesis method is presented that can achieve large-scale preparation of monodisperse and uniform silicate nanoscintillators. By simply adjusting the metal dopants, silicate nanoscintillators with controllable size and X-ray-excited optical luminescence (450-900 nm) are synthesized by employing a general ion-incorporated silica-templating method. To make full use of external radiation, the silicate nanoscintillators are conjugated with photosensitizer rose bengal and arginylglycylaspartic acid (RGD) peptide, making them intrinsically dual-modal targeted imaging probes. Both in vitro and in vivo experiments demonstrate that the silicate nanosensitizers can accumulate effectively in tumors and achieve significant inhibitory effect on tumor progression under low-dose X-ray irradiation, while minimally affecting normal tissues. The insights gained in this study may provide an attractive route to synthesize nanosensitizers to overcome some of the limitations of RT and PDT in cancer treatment.

Uncovering the genetic basis of seed development will provide useful tools for improving both crop yield and nutritional value. However, the genetic regulatory networks of maize (Zea mays) seed development remain largely unknown. The maize opaque endosperm and small germ 1 (os1) mutant has opaque endosperm and a small embryo. Here, we cloned OS1 and show that it encodes a putative transcription factor containing an RWP-RK domain. Transcriptional analysis indicated that OS1 expression is elevated in early endosperm development, especially in the basal endosperm transfer layer (BETL), conducting zone (CZ), and central starch endosperm (CSE) cells. RNA sequencing (RNA-Seq) analysis of the os1 mutant revealed sharp downregulation of certain genes in specific cell types, including ZmMRP-1 and Meg1 in BETL cells and a majority of zein- and starch-related genes in CSE cells. Using a haploid induction system, we show that wild-type endosperm could rescue the smaller size of os1 embryo, which suggests that nutrients are allocated by the wild-type endosperm. Therefore, our data imply that the network regulated by OS1 accomplishes a key step in nutrient allocation between endosperm and embryo within maize seeds. Identification of this network will help uncover the mechanisms regulating the nutritional balance between endosperm and embryo.

Aims 14,15-Epoxyeicosatrienoic acid (14,15-EET) is abundantly expressed in brain and exerts protective effects against ischaemia. 14,15-EET is hydrolysed by soluble epoxide hydrolase (sEH). sEH−/− mice show a higher level of 14,15-EET in the brain. Astrocytes play a pivotal role in neuronal survival under ischaemic conditions. However, it is unclear whether the neuroprotective effect of 14,15-EET is associated with astrocytes. Methods A mouse model of focal cerebral ischaemia was induced by middle cerebral artery occlusion. Oxygen–glucose deprivation/reoxygenation (OGD/R) was performed on cultured murine astrocytes, neurons and a human cell line. Cell viabilities were measured by 3-(4, 5-dimethyl-2-thiazolyl)-2, 5-diphenyl-2H-tetrazolium bromide (MTT) assay. The mRNA expressions were quantified by real-time PCR. Brain derived neurotrophic factor (BDNF) concentration was measured by ELISA. Protein expressions were quantified by Western blotting. BDNF and peroxisome proliferators-activated receptor gamma (PPAR-γ) expressions were analysed by confocal microscopy. Results Decreased infarct volumes, elevated BDNF expression and increased numbers of BDNF/GFAP Glial Fibrillary Acidic Protein double-positive cells were observed in the ischaemic penumbra of sEH−/− mice. The decreased infarct volumes of sEH−/− mice were diminished by intracerebroventricular injection of a blocker of BDNF receptor. 14,15-EET increases BDNF expression and cell viability of murine astrocytes and U251 cells by BDNF-TrkB Tyrosine receptor kinase-B-extracellular signal-regulated kinase 1/2 signalling during OGD/R. 14,15-EET protects neurons from OGD/R by stimulating the production of astrocyte-derived BDNF. 14,15-EET stimulates the production of astrocyte-derived BDNF through PPAR-γ/p-cAMP-response element binding protein signal pathways. Conclusions Our study demonstrates the importance of 14,15-EET-mediated production of astrocyte-derived BDNF for enhancing viability of astrocytes and protecting neurons from the ischaemic injury and provides insights into the mechanism by which 14,15-EET is involved in neuroprotection.

CRISPR/Cas (clustered regularly interspaced short palindromic repeats/CRISPR-associated proteins) is an adaptive immune system in bacteria and archaea to defend against invasion from foreign DNA fragments. Recently, it has been developed as a powerful targeted genome editing tool for a wide variety of species. However, its application in maize has only been tested with transiently expressed somatic cells or with a limited number of stable transgenic T0 plants. The exact efficiency and specificity of the CRISPR/Cas system in the highly complex maize genome has not been documented yet. Here we report an extensive study of the well-studied type II CRISPR-Cas9 system for targeted genome editing in maize, with the codon-optimized Cas9 protein and the short non-coding guide RNA generated through a functional maize U6 snRNA promoter. Targeted gene mutagenesis was detected for 90 loci by maize protoplast assay, with an average cleavage efficiency of 10.67%. Stable knockout transformants for maize phytoene synthase gene (PSY1) were obtained. Mutations occurred in germ cells can be stably inherited to the next generation. Moreover, no off-target effect was detected at the computationally predicted putative off-target loci. No significant difference between the transcriptomes of the Cas9 expressed and non-expressed lines was detected. Our results confirmed that the CRISPR-Cas9 could be successfully applied as a robust targeted genome editing system in maize.

All halogen containing electrolytes for Mg battery are apt to corrode conventional metal current collectors. In this paper, a new type of halogen-free boron based electrolyte (Mg[Mes3BPh]2/THF) is designed and prepared. Electrochemical tests show that this electrolyte system possesses high ion conductivity (1.5 × 10−3 S cm−1) and good Mg deposition–dissolution reversibility. More importantly, the same electrochemical window (2.6 V vs. Mg RE) of the electrolyte on Pt and stainless steel electrodes indicates that halogen-free electrolyte indeed lessens the corrosion to conventional metal current collectors. The surface morphologies of stainless steel, aluminum and copper are further observed after their anodic potentiostatic polarization in 0.25 mol L−1 Mg[Mes3BPh]2/THF electrolyte solution for 2 days. A comparison with halogen containing electrolytes proves that the presence of halogen in electrolyte is the reason for corrosion. This work provides a stepping stone for developing new halogen-free electrolyte systems for rechargeable Mg batteries.