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• Haploid and diploid T. dendrolimi can be differentiated by distinct ranges of 2−ΔCq values. • Mitochondrial number of T. dendrolimi significantly decreased with higher ploidy. • Mitochondrial number was also not affected by Wolbachia -infection. Ploidy diversity provides valuable scientific information, thus making the detection technique of ploidy important. However, traditional methods of cytological observation and flow cytometry are either laborious or expensive. We here report a simple and rapid, effective and economical quantitative PCR (qPCR) approach to determine the ploidy of a parasitoid species Trichogramma dendrolimi Matsumura, an economically important biocontrol agent. We applied a mitochondrial gene cytochrome oxidase (COI) and a nuclear gene forkhead to evaluate the mitochondrial number per nuclear copy in a thelytokous Wolbachia -infected strain of T. dendrolimi and its bisexual uninfected counterparts. The 2−ΔCq values calculated from C q values which resulted from qPCR experiments were significantly larger in haploid males than that in diploid females. Haploid males possessed about 2.69 times mitochondrial number per nuclear copy as diploid females. Not a single significant difference was found between diploid females from thelytokous and bisexual strains. Based on the differences in relative mitochondrial content, we were allowed to distinguish between haploid males and diploid females. Moreover, the number of mitochondria significantly decreased with higher ploidy level but was not affected by Wolbachia -infection. Our study supplied an available tool to investigate the ploidy diversity in sex determination of T. dendrolimi and thelytokous manipulation of Wolbachia , which is the crucial step to further study their underlying mechanisms. This will in turn contribute to the biocontrol efficiency by enhancing the female production and hence the parasitism rate. [ABSTRACT FROM AUTHOR]

The efficacy of Trichogramma against pests basically depends on the dispersal capacity of the wasps. A release-recapture method was used in this study to evaluate the effect of relative wind speed (RWS) during the nighttime and the daytime on the dispersal capacity of postrelease population of Trichogramma dendrolimi Matsumura. Two repeated measurements were carried out, using sentinel cards with the host eggs and yellow sticky card traps on the third and the sixth day after wasp release. The results showed that: (1) both the number of recaptured wasps and parasitized eggs increased with the RWS in the daytime during the first three days. The number of parasitized eggs also increased with the RWS in the daytime over the latter three days. The distances that encompassed 98% recaptured T. dendrolimi adults (X 98) at the first three days was quadratically increased by the RWS of the daytime. (2) The number of wasps recaptured decreased with the distance from the releasing point during the first three days, but it was not influenced by the distance from the releasing point during the latter three days. (3) The average dispersal radius of the wasps during the first three days was shorter than during the latter three days. The present results will be helpful to improve release techniques based on the wind effects at different times. Unlabelled Image • Tiny Trichogramma wasps are sensitive to wind in fields. • We measured the effect of wind at different times on T. dendrolimi dispersal. • Daytime wind is powerful in reconstructing dispersal patterns of T. dendrolimi. [ABSTRACT FROM AUTHOR]

Abstract In a probe–drogue aerial refueling system, the drogue is affected not only by wind disturbances but also by strong disturbances from the tanker vortex and receiver forebody bow wave. Along with the aerodynamic disturbances acting on the receiver aircraft, it is difficult for the probe to capture the moving drogue in the docking stage. This paper studies the model of the probe–drogue aerial refueling system under aerodynamic disturbances, and proposes docking control method based on iterative learning control to compensate for the docking errors caused by aerodynamic disturbances. For receiver aircraft with different maneuverability, three control strategies are proposed to achieve a trade-off between safety and control precision. Furthermore, a practical method is proposed to predict the initial value of the learning controllers, which can significantly improve the iterative learning speed of the proposed methods. Finally, simulations demonstrate that the proposed control methods are simple and efficient for the docking control of autonomous probe–drogue aerial refueling. [ABSTRACT FROM AUTHOR]

Abstract Objective To discuss the cardiac toxicities of a heat waves and ozone exposure on cardiovascular diseases (CVDs) and explore a possible mechanism. Methods The incidence of ozone exposure combined with heat wave was simulated in the Shanghai Meteorological and Environmental Animal Exposure System (Shanghai-METAS). A total of 64 ApoE−/− mice, matched by weight, were randomly divided into 8 groups and exposed to heat wave conditions or ozone. The levels of creatine kinase (CK), D-lactate dehydrogenase (D-LDH), intercellular adhesion molecule 1 (sICAM-1), tumor necrosis factor alpha (TNF-α), nitric oxide (NO), endothelin-1 (ET-1), D-dimer (D2D), plasminogen activator inhibitor-1 (PAI-1) and blood lipid in plasma and heat shock protein-60 (HSP60), hypoxia inducible factor 1 alpha (HIF-1α), interleukin-6 (IL-6), C-reactive protein (CRP), superoxide dismutase (SOD), and malondialdehyde (MDA) in hearts were measured after exposure. Results The levels of all indicators, except for SOD, increased with the ozone-only exposure. However, cardiac damage was most significant when the heat wave conditions were combined with severe ozone exposure. Moreover, the levels of CK, D-LDH, NO, PAI-1, sICAM-1, and TNF-α in plasma increased significantly (P < 0.05), and the contents of HSP60, HIF-1α, CRP, and MDA in hearts increased considerably (P < 0.05), but the activity of SOD decreased significantly. In addition, the levels of four blood lipid items remarkably increased (except the level of HDL-C which decreased significantly) with ozone exposure. Conclusion A short-term exposure to a heat wave and ozone causes severe toxic effects on the heart. Cardiac damage was most significant under combined heat wave and severe ozone exposure simulations. [ABSTRACT FROM AUTHOR]

Abstract Due to ongoing climate change, short-term extreme heat waves in the summer are expected to be more frequent. Insect eggs are sensitive to thermal stress. This raises the question of whether herbivore insects' thermal adaptability would be changed after a single extreme heat wave at the egg stage. In this study, we examined the developmental performance of Ostrinia furnacalis Guenée at 25 °C, 27 °C, 29 °C or 31 °C after a single extreme heat wave (42 °C) for 0 h (control), 1 h, 2 h, or 3 h at the egg stage. The results showed that O. furnacalis at the egg or larval stage was more sensitive to a single heat wave than it was at the pupae or adult stage. After a single heat wave, O. furnacalis showed a reduced egg-hatching rate or reduced larval survival rate, but the optimum temperature for egg hatching and larval survival was higher than that in the control. The upper temperature threshold and optimum temperature for larval development in the control were higher than that after a single extreme heat wave. Both male and female pupal weight decreased with increasing temperature, and pupal weight decreased faster in females than in males. The Cox proportional hazard model showed that when O. furnacalis developed at 25 °C, the instantaneous death risk of adults with a 3 h heat wave at the egg stage was higher than that of the control, but when O. furnacalis developed at 29 °C and 31 °C, the instantaneous death risk of adults after a heat wave was significantly lower than that of the control. Our study highlights the effect of a single heat wave on O. furnacalis eggs and the subsequent development of survival individuals. Graphical abstract Unlabelled Image Highlights • O. furnacalis eggs or larvae are susceptible to a extreme heat wave. • Extreme heat causes carry-over effects on larva or adult stage. • Optimum temperature for O. furnacalis is modified by a extreme heat wave. • O. furnacalis adult longevity varies with temperature and heat duration. [ABSTRACT FROM AUTHOR]

This paper presents an additive-state-decomposition-based attitude tracking control method for a class of bank-to-turn aerial vehicles subject to unknown disturbances and nonlinear coupling. This method ‘additively’ decomposes the original tracking problem into two more tractable problems, namely a tracking problem for a deterministic nonlinear ‘primary’ system, and a disturbance rejection problem for a linear time-invariant ‘secondary’ system. Based on the decomposition, a backstepping controller is designed for the primary system to track the reference attitude signal, and a proportional-integral controller is applied to the secondary system to compensate for the disturbances. Finally, the two designed controllers are combined to achieve the original control objective. By using additive state decomposition, the proposed control method with two degrees of freedom can consider tracking task and disturbance rejection task respectively. Simulation results illustrate that the proposed controller can track the reference attitude signal and compensate for disturbances meanwhile. Additionally, the ASD-based controller outperforms the traditional backstepping controller in the presence of unknown disturbances and input delay, and the robustness of the full system can be improved by adjusting the controller parameters of the secondary system. [ABSTRACT FROM AUTHOR]

Dental pulp stem cells (DPSCs) derived from the human dental pulp tissue have multiple differentiation capabilities, such as osteo/odontogenic differentiation. Therefore, DPSCs are deemed as ideal stem cell sources for tissue regeneration. As new nanomaterials based on DNA, tetrahedral DNA nanostructures (TDNs) have tremendous potential for biomedical applications. Here, the authors aimed to explore the part played by TDNs in proliferation and osteo/odontogenic differentiation of DPSCs, and attempted to investigate if these cellular responses could be driven by activating the canonical Notch signaling pathway. Upon exposure to TDNs, proliferation and osteo/odontogenic differentiation of DPSCs were dramatically enhanced, accompanied by up regulation of Notch signaling. In general, our study suggested that TDNs can significantly promote proliferation and osteo/odontogenic differentiation of DPSCs, and this remarkable discovery can be applied in tissue engineering and regenerative medicine to develop a significant and novel method for bone and dental tissue regeneration. [ABSTRACT FROM AUTHOR]

For multicopters, failures may abort missions, crash multicopters, and moreover, injure or even kill people. In order to guarantee flight safety, a system of prognostics and health management should be designed to prevent or mitigate unsafe consequences of multicopter failures, where health evaluation is an indispensable module. This paper proposes a health evaluation method of multicopters based on Stochastic Hybrid System (SHS). In the SHS model, different working conditions (health statuses) of multicopters are modeled as discrete states, and system behaviors of different working conditions are modeled as continuous dynamics under discrete states. Then, the health of multicopters is quantitatively measured by a definition of health degree, which is a probability measure describing an extent of system degradation from an expected normal condition. On this basis, the problem of multicopter's health evaluation is transformed to a hybrid state estimation problem. In this case, a modified interacting-multiple-model algorithm is proposed to estimate the real-time distribution of hybrid state, and evaluate multicopter's health. Finally, a case study of multicopter with sensor anomalies is presented to validate the effectiveness of the proposed method. [ABSTRACT FROM AUTHOR]

Health performance prediction of a dynamical system aims at determining the probability or possibility that the system state will remain in a permitted area (safe set) or reach a forbidden area (unsafe set) at a future time instance. This paper proposes a health performance prediction algorithm for large-scale Stochastic Linear Hybrid Systems (SLHS) with small failure probability. In the studied SLHS, the continuous variable evolution is described by a set of stochastic linear differential equations, and the discrete state evolution is modeled by a first-order Markov chain. Furthermore, a safe set of the SLHS is described by a permitted area in the hybrid state space. Given an initial condition, a hybrid state evolution algorithm is proposed referring to the execution of stochastic hybrid systems. On this basis, a concept of health degree is introduced to evaluate the health performance of the studied SLHS. Finally, a multicopter with sensor anomalies is studied to validate the availability and effectiveness of the proposed method. [ABSTRACT FROM AUTHOR]

Previous proteomic analyses have shown that aminoacyltRNA synthetases in many organisms can be modified by acetylation of Lys. In this present study, leucyl-tRNA synthetase and arginyl-tRNA synthetase from Escherichia coli (EcLeuRS and EcArgRS) were overexpressed and purified and found to be acetylated on Lys residues by MS. Gln scanning mutagenesis revealed that Lys619, Lys624, and Lys809 in EcLeuRS and Lys126 and Lys408 in EcArgRS might play important roles in enzyme activity. Furthermore, we utilized a novel protein expression system to obtain enzymes harboring acetylated Lys at specific sites and investigated their catalytic activity. Acetylation of these Lys residues could affect their aminoacylation activity by influencing amino acid activation and/or the affinity for tRNA. In vitro assays showed that acetyl-phosphate nonenzymatically acetylates EcLeuRS and EcArgRS and suggested that the sirtuin class deacetylase CobB might regulate acetylation of these two enzymes. These findings imply a potential regulatory role for Lys acetylation in controlling the activity of aminoacyl-tRNA synthetases and thus protein synthesis. [ABSTRACT FROM AUTHOR]