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Nitric oxide (NO) has been shown to play an important role in the plant response to biotic and abiotic stresses in Arabidopsis mutants with lower or higher levels of endogenous NO. The exogenous application of NO donors or scavengers has also suggested an important role for NO in plant defense against environmental stress. In this study, rice plants under drought and high salinity conditions showed increased nitric oxide synthase (NOS) activity and NO levels. Overexpression of rat neuronal NO synthase (nNOS) in rice increased both NOS activity and NO accumulation, resulting in improved tolerance of the transgenic plants to both drought and salt stresses. nNOS-overexpressing plants exhibited stronger water-holding capability, higher proline accumulation, less lipid peroxidation and reduced electrolyte leakage under drought and salt conditions than wild rice. Moreover, nNOS-overexpressing plants accumulated less H2O2, due to the observed up-regulation of OsCATA, OsCATB and OsPOX1. In agreement, the activities of CAT and POX were higher in transgenic rice than wild type. Additionally, the expression of six tested stress-responsive genes including OsDREB2A, OsDREB2B, OsSNAC1, OsSNAC2, OsLEA3 and OsRD29A, in nNOS-overexpressing plants was higher than that in the wild type under drought and high salinity conditions. Taken together, our results suggest that nNOS overexpression suppresses the stress-enhanced electrolyte leakage, lipid peroxidation and H2O2 accumulation, and promotes proline accumulation and the expression of stress-responsive genes under stress conditions, thereby promoting increased tolerance to drought and salt stresses.

A systematic interrogation of male germ cells is key to complete understanding of molecular mechanisms governing spermatogenesis and the development of new strategies for infertility therapies and male contraception. Here we develop an approach to purify all types of homogeneous spermatogenic cells by combining transgenic labeling and synchronization of the cycle of the seminiferous epithelium, and subsequent single-cell RNA-sequencing. We reveal extensive and previously uncharacterized dynamic processes and molecular signatures in gene expression, as well as specific patterns of alternative splicing, and novel regulators for specific stages of male germ cell development. Our transcriptomics analyses led us to discover discriminative markers for isolating round spermatids at specific stages, and different embryo developmental potentials between early and late stage spermatids, providing evidence that maturation of round spermatids impacts on embryo development. This work provides valuable insights into mammalian spermatogenesis, and a comprehensive resource for future studies towards the complete elucidation of gametogenesis.

The development of the plant root system is highly plastic, which allows the plant to adapt to various environmental stresses. Salt stress inhibits root elongation by reducing the size of the root meristem. However, the mechanism underlying this process remains unclear. In this study, we explored whether and how auxin and nitric oxide (NO) are involved in salt-mediated inhibition of root meristem growth in Arabidopsis (Arabidopsis thaliana) using physiological, pharmacological, and genetic approaches. We found that salt stress significantly reduced root meristem size by down-regulating the expression ofPINFORMED (PIN)genes, thereby reducing auxin levels. In addition, salt stress promoted AUXIN RESISTANT3 (AXR3)/INDOLE-3-ACETIC ACID17 (IAA17) stabilization, which repressed auxin signaling during this process. Furthermore, salt stress stimulated NO accumulation, whereas blocking NO production with the inhibitorNω -nitro-L-arginine-methylester compromised the salt-mediated reduction of root meristem size,PINdown-regulation, and stabilization of AXR3/IAA17, indicating that NO is involved in salt-mediated inhibition of root meristem growth. Taken together, these findings suggest that salt stress inhibits root meristem growth by repressingPINexpression (thereby reducing auxin levels) and stabilizing IAA17 (thereby repressing auxin signaling) via increasing NO levels.

In this paper, a novel swarm-based metaheuristic algorithm is proposed, which is called tuna swarm optimization (TSO). The main inspiration for TSO is based on the cooperative foraging behavior of tuna swarm. The work mimics two foraging behaviors of tuna swarm, including spiral foraging and parabolic foraging, for developing an effective metaheuristic algorithm. The performance of TSO is evaluated by comparison with other metaheuristics on a set of benchmark functions and several real engineering problems. Sensitivity, scalability, robustness, and convergence analyses were used and combined with the Wilcoxon rank-sum test and Friedman test. The simulation results show that TSO performs better compared to other comparative algorithms.

Background Most ABC transporters are engaged in transport of various compounds, but its subfamily F lacks transmembrane domain essential for chemical transportation. Thus the function of subfamily F remains further elusive. Results Here, we identified General Control Non-Repressible 20 (GCN20), a member of subfamily F, as new factor for DNA damage repair in root growth. While gcn20–1 mutant had a short primary root with reduced meristem size and cell number, similar primary root lengths were assayed in both wild-type and GCN20::GCN20 gcn20–1 plants, indicating the involvement of GCN20 in root elongation. Further experiments with EdU incorporation and comet assay demonstrated that gcn20–1 displays increased cell cycle arrest at G2/M checkpoint and accumulates more damaged DNA. This is possible due to impaired ability of DNA repair in gcn20–1 since gcn20–1 seedlings are hypersensitive to DNA damage inducers MMC and MMS compared with the wild type plants. This note was further supported by the observation that gcn20–1 is more sensitive than the wild type when subjected to UV treatment in term of changes of both fresh weight and survival rate. Conclusions Our study indicates that GCN20 functions in primary root growth by modulating DNA damage repair in Arabidopsis. Our study will be useful to understand the functions of non-transporter ABC proteins in plant growth.

In order to study the influence of subarea excavation on the deformation and stress behavior of a subway foundation pit, the deep horizontal wall displacement, supporting axial force and surface deformation were measured and compared with other similar pit cases according to the case of a soft soil deep foundation pit for a metro station in Hangzhou. The results of the theoretical and experimental studies show that zoned excavation can reduce the aspect ratio of a single foundation pit and then the spatial effect of small excavation can be mobilized, which can effectively control lateral wall deformation and wall deformation. Higher stiffness can strengthen the integrity of the foundation pit and provide more lateral force to prevent excessive axial force fluctuation in the deep foundation pit, and its restraining effect is greater than the first excavation foundation pit. The difference in the distribution of buildings on both sides of the long and narrow pit will lead to a different deformation of the walls on both sides, which warrants attention in the design and construction.

Meiotic recombination is initiated by the formation of double-strand breaks (DSBs), which are repaired as either crossovers (COs) or noncrossovers (NCOs). In most mammals, PRDM9-mediated H3K4me3 controls the nonrandom distribution of DSBs; however, both the timing and mechanism of DSB fate control remain largely undetermined. Here, we generated comprehensive epigenomic profiles of synchronized mouse spermatogenic cells during meiotic prophase I, revealing spatiotemporal and functional relationships between epigenetic factors and meiotic recombination. We find that PRDM9-mediated H3K4me3 at DSB hotspots, coinciding with H3K27ac and H3K36me3, is intimately connected with the fate of the DSB. Our data suggest that the fate decision is likely made at the time of DSB formation: earlier formed DSBs occupy more open chromatins and are much more competent to proceed to a CO fate. Our work highlights an intrinsic connection between PRDM9-mediated H3K4me3 and the fate decision of DSBs, and provides new insight into the control of CO homeostasis.

Male infertility has become an increasingly common health concern in recent years. Apart from environmental factors, nutrition, lifestyle, and sexually transmitted diseases, genetic defects are important causes of male infertility. Many genes have been demonstrated to be associated with male infertility. However, the roles of some functional genes in infertility, especially those that are specifically expressed in the reproductive system, remain to be elucidated. Here, we demonstrated that the testis-specific gene coiled-coil domain-containing 87 (Ccdc87) is critical for male fertility. Reverse-transcriptase polymerase chain reaction and western blot analyses revealed that the Ccdc87 mRNA and protein were only expressed in mouse testis. Ccdc87 expression first appeared at postnatal day 14 and remained at a relatively high level until adulthood. Male mice lacking Ccdc87 gene (Ccdc87−/−) were found to be subfertile. Approximately 20% of Ccdc87-null sperm from the testis and epididymis displayed severe abnormity of acrosome and cell nucleus. Sperm isolated from the cauda epididymides of Ccdc87−/− mice exhibited decreased initial motility but did not show any change in capacitation. Additionally, Ccdc87 disruption led to the impotency of sperm spontaneous and progesterone-induced acrosome reaction. Moreover, in vitro fertilization assays indicated that the fertilizing capacity of Ccdc87−/− sperm was significantly reduced. Taken together, these findings provide a new clue to understand the genetic causes of male infertility. Summary Sentence A testis-specific protein, coiled-coil domain-containing 87 (CCDC87), plays critical roles in male fertility as a participant to regulate sperm morphology and acrosome reaction.

The unmanned aerial vehicle (UAV) path planning problem is a type of complex multi-constraint optimization problem that requires a reasonable mathematical model and an efficient path planning algorithm. In this paper, the fitness function including fuel consumption cost, altitude cost, and threat cost is established. There are also four set constraints including maximum flight distance, minimum flight altitude, maximum turn angle, and maximum climb angle. The constrained optimization problem is transformed into an unconstrained optimization problem by using the penalty function introduced. To solve the model, a multiple population hybrid equilibrium optimizer (MHEO) is proposed. Firstly, the population is divided into three subpopulations based on fitness and different strategies are executed separately. Secondly, a Gaussian distribution estimation strategy is introduced to enhance the performance of MHEO by using the dominant information of the populations to guide the population evolution. The equilibrium pool is adjusted to enhance population diversity. Furthermore, the Lévy flight strategy and the inferior solution shift strategy are used to help the algorithm get rid of stagnation. The CEC2017 test suite was used to evaluate the performance of MHEO, and the results show that MHEO has a faster convergence speed and better convergence accuracy compared to the comparison algorithms. The path planning simulation experiments show that MHEO can steadily and efficiently plan flight paths that satisfy the constraints, proving the superiority of the MHEO algorithm while verifying the feasibility of the path planning model.

To determine the efficacy of acupuncture for hypertension. Seven electronic databases were searched on April 13, 2014 to include eligible randomized controlled trials (RCTs). Data were extracted and risk of bias was assessed. Subgroup analyses and meta- analysis were performed. 23 RCTs involving 1788 patients were included. Most trials had an unclear risk of bias regarding allocation concealment, blinding, incomplete outcome data and selective reporting. Compared with sham acupuncture plus medication, a meta-analysis of 2 trials revealed that acupuncture as an adjunct to medication was more effective on systolic (SBP) and diastolic (DBP) blood pressure change magnitude (n=170, SBP: mean difference (MD)= -7.47,95% confidence intervals (CI):-10.43 to -4.51,I2 =0%; DBP: -4.22,-6.26 to -2.18, 0%).A subgroup analysis of 4 trials also showed acupuncture combined with medication was superior to medication on efficacy rate (n=230, odds ratio (OR)=4.19, 95%CI: 1.65 to 10.67, I2 =0%). By contrast, compared with medication, acupuncture alone showed no significant effect on SBP /DBP after intervention and efficacy rate in the subgroup analysis. (7 trials with 510 patients, SBP: MD=-0.56, 95%CI:-3.02 to 1.89,I2 =60%; DBP: -1.01,-2.26 to 0.24, 23%; efficacy rate: 10 trials with 963 patients, OR=1.14, 95% CI: 0.70 to 1.85, I2 =54%).Adverse events were inadequately reported in most RCTs. Our review provided evidence of acupuncture as an adjunctive therapy to medication for treating hypertension, while the evidence for acupuncture alone lowing BP is insufficient. The safety of acupuncture is uncertain due to the inadequate reporting of it. However, the current evidence might not be sufficiently robust against methodological flaws and significant heterogeneity of the included RCTs. Larger high-quality trials are required.