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In Jupiter missions, one significant challenge is the harsh environment. The radiation in Jovian orbit is much higher than that in earth bf vicinity in terms of intensity and energy level. In spacecraft (S/C) design, key electronics are packaged in an enclosed vault to help them survive through the mission. The preliminary optimization design methods of a radiation vault based on a genetic algorithm (GA) are introduced, including shield structure optimization and layout pattern of electronics optimization. In shield structure optimization, the method is combined with a total ionizing dose (TID) evaluation tool. The goal is to find the optimal multi-layer shield structure so that the TID, after the shielding, is minimal within the threshold of the total mass of the structure. In a 1-year mission with an orbit of $10\,\,R_{j}\times 25\,\,R_{j} \times 0^{\circ }$ , if the areal density is within 0.5–3 g/cm2, the optimal structure is bilayer or trilayer with high-Z material as an external layer and low-Z material as an internal layer. This structure benefits from the fact that the low-Z material is more effective in shielding energetic protons whereas the high-Z material is more effective in shielding energetic electrons. In the 1-g/cm2 situation, the optimal structure is a 0.829-mm lead layer combined with a 0.158-mm magnesium layer. Comparing with the traditional aluminum shielding structure, about 43.6% of mass can be saved. In layout pattern optimization, this method combines a packing algorithm and a 3-D TID simulation tool. Using this method, an effective design layout of the vault can be found. In this design, all avionics can survive through the mission. In addition, the mass of the vault is low enough that the layout pattern is acceptable in S/C design. As an example, 14 instruments with TID threshold of 50 krad (Si) are packaged in a vault. On the premise that one instrument’s walls are thickened to 3.5-mm aluminum, the total mass of the vault is 68.47 kg. This method is a starting point for the iterative design of the radiation vault and gives principle guidelines for the designers.

By analyzing the newly released in situ data in medium earth orbit (MEO) of global positioning system satellites, we studied the spatiotemporal distribution and statistical characteristics of electrons over one solar cycle. The Weibull distribution of daily-averaged flux cumulative occurrence probability is proven. For >2-MeV electron flux, the determination coefficient of Weibull fitting is 99.92%. In the magnetic storm of late July 2004, the radial diffusion of electrons to low L-shell position was obvious. The center of 0.04-MeV electrons moved inward from $L = 6$ to $L = 4.3$ in the main phase and moved outward slowly in the recovery phase. In 0–4 MeV range, the in situ electron flux data are consistent with the AE9 mean and MEO-v2 model. The percentile of the AE9 model is also validated. The differential spectra are fitted based on exponential function at different percentiles. We also develop a rapid analysis method of internal charging in a changing electron environment. Using this method, we find that the electric field of internal charging fluctuates a lot because of the time-varying electron environment in MEO. The charging processes of different dielectrics (time constant ranges from 1 day to 100 days) in one solar cycle are also simulated. The longer the time constant, the bigger is the maximum charging electric field. But the worst case flux needed for discharging hazard evaluation is smaller. The daily-averaged worst case flux for charging assessment is not applicable.

Internal charging is an important hazard for navigation satellites, which operate in outer electron radiation belt and experience a very variable radiation environment because of the inclination of orbits. A rapid analysis method of internal charging is introduced, including physical model, conductivity model, shielding and electron transportation algorithm, and charging calculation method. Using this method, we calculate the charging processes of dielectric in medium earth orbit (MEO), geostationary earth orbit (GEO), and inclined geosynchronous orbit (IGSO). The results show that charging field fluctuates a lot in orbit and variation rate of field is proportional to electron flux. The saturated charging field in MEO is higher than that in GEO, and the field in GEO is higher than that in IGSO. So, the internal electrostatic discharging risk in MEO, GEO, and IGSO decreases in turn. If conductivity of dielectric is smaller, saturated field is larger and the difference of field in MEO, GEO, and IGSO is smaller. The dark and radiation-induced conductivity (RIC) of dielectric are important parameters in simulation, so we study the impact of conductivity in charging processes. In IGSO and MEO, when dark conductivity-induced time constant of charging is greater than orbital period and RIC is not large, the deposited electrons between different orbits accumulate and the charging field increase constantly. In this situation, the dark conductivity has a big influence on internal charging and it is important to measure it accurately.

It is generally supposed that a transition from the normal decay phase (decay slope $\sim -1$) to a steeper phase (decay slope $\sim -2$) could be suggested as a jet break. The jet opening angle $\theta_{\rm jet}$ is then calculated from the jet break time of the afterglow light curve. This allows the derivation of the collimation-corrected energy $E_{\rm jet}$ of those GRBs. We extensively searched for the GRBs with jet break features from multi-wavelength afterglow light curves, and 138 GRBs with significant breaks were collected. The jet break times of those GRBs mainly range from 1000 s to $10^6$ s, and the distribution of the collimation-corrected energy $E_{\rm jet}$ peaks at $\sim10^{50}$ erg. We also confirmed the $E_{\rm \gamma,iso}-E_{\rm p,i}$, $E_{\rm jet}-E_{\rm p,i}$ and $E_{\rm \gamma,iso}-\theta_{\rm jet}$ relations, and found $E_{\rm \gamma,iso}-T_{\rm j,z}-E_{\rm p,i}$ relation remains tight with more multi-wavelength data. This tight $E_{\rm \gamma,iso}-T_{\rm j,z}-E_{\rm p,i}$ relation is also conformed by different groups of our selected GRBs in the paper. In addition, another two new and tighter correlations among $E_{\rm jet}-T_{\rm j,z}-E_{\rm p,i}$ are well confirmed for different circumburst mediums in this paper. We suggest that those tight three-parameter correlations are more physical, and could be widely applied to constrain the cosmological parameters., Comment: 11 pages, 4 figures and 2 tables; final version published in ApJ

New Findings What is the central question of this study? It is not known whether treatment with interleukin-10 (IL-10) attenuates hyperoxia-induced acute lung injury in mice. What is the main finding and its importance? Our results showed that exogenous IL-10 treatment alleviated hyperoxia-induced acute lung injury in mice, possibly by regulating neutrophil recruitment and the subsequent generation of cytokines, nitric oxide and matrix metalloproteinases. Lung injury caused by breathing air enriched with oxygen continues to be a major problem in clinical medicine. Here, we investigated the therapeutic role of interleukin-10 (IL-10) in hyperoxia-induced acute lung injury in mice. In the first experiment, mice were exposed to room air or 95% O2 and treated with IL-10 simultaneously. In the second experiment, wild-type mice and IL-10−/− mice were exposed to room air or 95% O2. Exogenous IL-10 treatment attenuated hyperoxia-induced acute lung injury, evidenced by a reduced ratio of lung weight to body weight, ratio of lung wet weight to dry weight, cell numbers and protein content in bronchoalveolar lavage fluid and cell death. Interleukin-10 treatment markedly prolonged the survival of mice during oxygen exposure. Interleukin-10 treatment reduced the activity of myeloperoxidase and mRNA levels of interleukin-6, tumour necrosis factor-α and macrophage inflammatory protein 2, suppressed nuclear factor-κB activation and decreased inducible nitric oxide synthnase expression and nitric oxide formation in lungs of mice exposed to hyperoxia. Interleukin-10 treatment suppressed activities of matrix metalloproteinase 2 and matrix metalloproteinase 9 and reduced lung permeability in mice during oxygen exposure. Furthermore, absence of IL-10 aggravated hyperoxia-induced acute lung injury and reduced the duration of survival of mice during oxygen exposure, which was attenuated by treatment with IL-10. In conclusion, our results show that exogenous IL-10 treatment alleviates hyperoxia-induced acute lung injury in mice, possibly by regulating neutrophil recruitment and the subsequent generation of cytokines, nitric oxide and matrix metalloproteinases. This suggests that IL-10 treatment may be a promising therapeutic strategy to reduce lung injury in patients exposed to hyperoxia.

To investigate the clinical effect of the arytenoid cartilage reposition using snake mouth reduction forceps under general anesthesia.Data of twenty-six cases accepted arytenoid cartilage reposition under intravenous general anesthesia were analyzed, nineteen cases accepted laryngeal CT scan and cricoarytenoid joint reconstruction, all patients underwent endolaryngeal muscle electromyography examination. According to the position of cartilage dislocation prompted by laryngoscope and CT, the arytenoid cartilage was repositoned under the visual laryngoscope using special snake mouth reduction forceps. If bilateral arytenoid cartilage were still asymmetrically at the end of the surgery, patients needed repeated reposition 1 to 2 times 1 week after operation. The efficacy was evaluated 4 weeks later.All patients had a hoarse and breathing voice preoperative. Under laryngoscope, there were different degrees of vocal cord movement disorders accompanied by incomplete glottis closure, 22 cases happened in left side and 4 in right side. The arytenoid cartilage was dislocated anteromedially in 25 cases and posterolaterally in 1 case. CT showed that 15 cases of arytenoid cartilage were tilted anteromedially; the interval of the cricoarytenoid joint was widened. In axial CT images, there were no direct signs of the arytenoid cartilage dislocation in the 4 cases, but the abnormal position was seen in the reconstruction images. The laryngeal electromyography indicated that 7 cases were abnormal, duration of motor unit potential were visible and the raising potential were mixed. There were 4 patients with normal voice in the first day after surgery, and 19 cases underwent twice and 3 cases underwent three times surgery. Vioce became normal in 4 weeks. Swallowing pain and bucking were all disappeared. Vocal cords movement were recovered to normal level in 25 cases. In 1 case with neck strangulation, the vocal cord movement was slightly worse than health side, but significantly better than that before operation.The arytenoid cartilage reposition using snake mouth reduction forceps under general anesthesia was an effective method for the treatment of the cricoary-tenoid joint dislocation.

The bone protective effects of the hydrogen molecule (H2) have been demonstrated in several osteoporosis models while the underlying molecular mechanism has remained unclear. Osteoclast differentiation is an important factor related to the pathogenesis of bone-loss related diseases. In this work, we evaluated the effects of incubation with H2 on receptor activator of NFκB ligand (RANKL)-induced osteoclast differentiation. We found that treatment with H2 prevented RANKL-induced osteoclast differentiation in RAW264.7 cells and BMMs. Treatment with H2 inhibits the ability to form resorption pits of BMMs stimulated by RANKL. Treatment with H2 reduced mRNA levels of osteoclast-specific markers including tartrate resistant acid phosphatase, calcitonin receptor, cathepsin K, metalloproteinase-9, carbonic anhydrase typeII, and vacuolar-type H(+)-ATPase. Treatment with H2 decreased intracellular reactive oxygen species (ROS) formation, suppressed NADPH oxidase activity, down-regulated Rac1 activity and Nox1 expression, reduced mitochondrial ROS formation, and enhanced nuclear factor E2-related factor 2 nuclear translocation and heme oxygenase-1 activity. In addition, treatment with H2 suppressed RANKL-induced expression of nuclear factor of activated T cells c1 and c-Fos. Furthermore, treatment with H2 suppressed NF-κB activation and reduced phosphorylation of p38, extracellular signal-regulated kinase, c-Jun-N-terminal kinase, and protein kinases B (AKT) stimulated with RANKL. In conclusion, hydrogen molecules prevented RANKL-induced osteoclast differentiation associated with inhibition of reactive oxygen species formation and inactivation of NF-κB, mitogen-activated protein kinase and AKT pathways.

Through the structure instability theory analysis of the coal roadway roof ,the author concluded that mechanical properties of rock, location, thickness and thickness ratio is the main factor affecting the instability and failure of rock structure. Capitalize on the roof caving hidden danger detector developed by the China university of mining and technology to synchronize, continuous and intensive monitor the rotational speed, thrust for synchronization and thrust. Based on the record ,the author inferred the coal seam roof lithology and rock structures of the different drilling location. Engineering practice shows that the use of roof caving hidden danger detector to identify lithology of strata and structure is in good agreement with the core test values. Coincidence rate reached 95.14% and the recognition effect is quite good.

The aim of this work was to test the effect of treatment with hydrogen sulfide (H2S) on hyperoxia-induced acute lung injury in mice. Mice were exposed to room air or 95 % O2, and treated with NaHS (intraperitoneal injection of 0.1 ml/kg/day of 0.56 mol/l NaHS). Treatment with H2S partly restored the reduced H2S levels in plasma and lungs of mice exposed to hyperoxia. Treatment with H2S attenuated hyperoxia-induced acute lung injury marked by reduced ratio of lung weight to body weight, ratio of lung wet weight to dry weight, and cell numbers and protein content in bronchoalveolar lavage (BAL) and decreased apoptosis. Treatment with H2S markedly prolonged the survival of mice under oxygen exposure. Treatment with H2S abated hyperoxia-induced oxidative stress marked by reduced malondialdehyde and peroxynitrite formation, reduced NADPH oxidase activity, enhanced translocation of nuclear factor E2-related factor (Nrf2) into nucleus and increased activity of HO-1. Treatment with H2S decreased IL-1β, MCP-1, and MIP-2, and increased IL-10 expression in lungs of mice exposed to hyperoxia. Treatment with H2S decreased NFκB activity and iNOS expression in lungs, and reduced NOx content in BAL of mice exposed to hyperoxia. Treatment with H2S reduced lung permeability and suppressed VEGF release and VEGFR2 expression in lungs of mice under oxygen exposure. Treatment with exogenous H2S attenuated hyperoxia-induced acute lung injury through abating oxidative stress, suppressing inflammation, and reducing lung permeability in mice.

Motor is one of the cores of electric vehicle, the performances of motor directly impact the performances of electric vehicle. The development of drive motor applied in electric vehicle is reviewed, the advantages and defects of several kinds of the motor developed in recent years are summarized, and the applications of control strategy too. The development of permanent magne brushless motors is prospected.

Soft error caused by single event upset has been a severe challenge to aerospace-based computing. Silent data corruption (SDC) is one of the results incurred by soft error. SDC occurs when a program generates erroneous output with no indications. SDC is the most insidious type of results and very difficult to detect. To address this problem, we design and implement an invariant-based system called Radish. Invariants describe certain properties of a program; for example, the value of a variable equals a constant. Radish first extracts invariants at key program points and converts invariants into assertions. It then hardens the program by inserting the assertions into the source code. When a soft error occurs, assertions will be found to be false at run time and warn the users of soft error. To increase the coverage of SDC, we further propose an extension of Radish, named Radish_D, which applies software-based instruction duplication mechanism to protect the uncovered code sections. Experiments using architectural fault injections show that Radish achieves high SDC coverage with very low overhead. Furthermore, Radish_D provides higher SDC coverage than that of either Radish or pure instruction duplication.

What is the central question of this study? It is not known whether treatment with interleukin-10 (IL-10) attenuates hyperoxia-induced acute lung injury in mice. What is the main finding and its importance? Our results showed that exogenous IL-10 treatment alleviated hyperoxia-induced acute lung injury in mice, possibly by regulating neutrophil recruitment and the subsequent generation of cytokines, nitric oxide and matrix metalloproteinases. Lung injury caused by breathing air enriched with oxygen continues to be a major problem in clinical medicine. Here, we investigated the therapeutic role of interleukin-10 (IL-10) in hyperoxia-induced acute lung injury in mice. In the first experiment, mice were exposed to room air or 95% O2 and treated with IL-10 simultaneously. In the second experiment, wild-type mice and IL-10(-/-) mice were exposed to room air or 95% O2 . Exogenous IL-10 treatment attenuated hyperoxia-induced acute lung injury, evidenced by a reduced ratio of lung weight to body weight, ratio of lung wet weight to dry weight, cell numbers and protein content in bronchoalveolar lavage fluid and cell death. Interleukin-10 treatment markedly prolonged the survival of mice during oxygen exposure. Interleukin-10 treatment reduced the activity of myeloperoxidase and mRNA levels of interleukin-6, tumour necrosis factor-α and macrophage inflammatory protein 2, suppressed nuclear factor-κB activation and decreased inducible nitric oxide synthnase expression and nitric oxide formation in lungs of mice exposed to hyperoxia. Interleukin-10 treatment suppressed activities of matrix metalloproteinase 2 and matrix metalloproteinase 9 and reduced lung permeability in mice during oxygen exposure. Furthermore, absence of IL-10 aggravated hyperoxia-induced acute lung injury and reduced the duration of survival of mice during oxygen exposure, which was attenuated by treatment with IL-10. In conclusion, our results show that exogenous IL-10 treatment alleviates hyperoxia-induced acute lung injury in mice, possibly by regulating neutrophil recruitment and the subsequent generation of cytokines, nitric oxide and matrix metalloproteinases. This suggests that IL-10 treatment may be a promising therapeutic strategy to reduce lung injury in patients exposed to hyperoxia.

To discuss the relationship between structural change in nasal cavity and the change of nasal ventilatory function after outfracture of the inferior turbinate.The inferior turbinate outfracture surgery was performed on 50 chronic hypertrophic rhinitis patients who suffered inferior turbinate hypertrophy according to endoscopy and CT scan. Preoperative and postoperative nasal endoscopy was carried out on all patients, by which the distance from the inferior turbinate front mucous membrane to nasal septum (DTNS) was measured. In addition, CT was used to measure the minimal distance between the inside edges of the bilateral inferior turbinate soft tissue (MDTT) and the minimal distance between the bilateral inferior turbinate bones (MDTB) at the central layer of coronal sectional infundibulum; the minimal distance between the inferior turbinate at asial nasal limen (NLDT); inferior turbinate thickness (ITT). In this way, the change in the structure of nasal cavity was evaluated. Acoustic rhinometry and rhinomanometry were utilized to evaluate the ventilatory function of the nasal cavity objectively. Visual analogue scale (VAS) was applied to evaluate the severity of preoperative and postoperative nasal obstruction subjectively. The test data were used to perform match t-test; Spearman rank correlation was adopted to evaluate the relationship between patients' bilateral VAS and nasal inspiratory effective resistance (IER),nasal expiratory effective resistance (EER) and DTNS. The relationship between the total resistance of nasal inspiratory phase as well as the total resistance of nasal expiratory phase and MDTT and MDTB was analyzed. SPSS 20.0 software was used to analyze the data.The preoperative data showed that rightward DTNS was (0.12 ± 0.07) cm, leftward DTNS was (0.10 ± 0.07) cm and MDTT was (0.70 ± 0.13) cm, and postoperative data showed that rightward DTNS was (0.47 ± 0.27) cm, leftward DTNS was (0.43 ± 0.15) cm, and MDTT was (1.05 ± 0.15) cm. Significant differences existed in rightward DTNS, leftward DTNS and MDTT between pre-and post operative data (t values were -8.827, -8.590, -17.525, all P0.05). According to the preoperative and postoperative comparison, the difference in MDTB, NLDT, rightward ITT, leftward ITT, IER, EER, 0-5 cm nasal cavity volume (0-5 cm NCV), nasal minimal cross-sectional area (NMCA), rightward VAS and leftward VAS had statistical significance (t values were -23.562, -8.374, 8.693, 6.684, 12.021, 14.510, -6.074, -2.285, 14.042 and 9.925, respectively, all P0.05). Patients' bilateral VAS grades had a positive relationship with IER and EER (left side: r values were 0.541 and 0.660, respectively,right side: r values were 0.940 and 0.688, respectively, all P0.05). Additionally, patients' VAS had a negative relationship with DTNS (r value was -0.861, P0.05). Besides,the total resistance of nasal inspiratory phase had a negative relationship with both MDTT and MDTB (r values were -0.565 and -0.546,respectively, all P0.05). The total resistance of nasal expiratory phase had a negative relationship with both MDTT and MDTB (r values were -0.562 and -0.546, all P0.05).The inferior turbinate outfracture surgery was an ideal surgical method by which nasal cavity could be broadened and nasal ventilatory function improved.

In this paper, new classes of generalized invex functions called B - (p, r, a)-invex, B - (p, r, a)-quasi invex and B - (p, r, a)-pseudo invex functions are introduced, which are defined by relaxing the definitions of B - (p, r)-invex, B - (p, r)-quasi-invex, B - (p, r)-pseudo-invex functions, then generalized minimax fractional programming involving such functions is reseached, the sufficient conditions for optimality are obtained under weeker convexity.