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The target backsheath field acceleration mechanism is one of the main mechanisms of laser-driven proton acceleration (LDPA) and strongly depends on the comprehensive performance of the ultrashort ultra-intense lasers used as the driving sources. The successful use of the SG-II Peta-watt (SG-II PW) laser facility for LDPA and its applications in radiographic diagnoses have been manifested by the good performance of the SG-II PW facility. Recently, the SG-II PW laser facility has undergone extensive maintenance and a comprehensive technical upgrade in terms of the seed source, laser contrast and terminal focus. LDPA experiments were performed using the maintained SG-II PW laser beam, and the highest cutoff energy of the proton beam was obviously increased. Accordingly, a double-film target structure was used, and the maximum cutoff energy of the proton beam was up to 70 MeV. These results demonstrate that the comprehensive performance of the SG-II PW laser facility was improved significantly.
Paravulvus zhongshanensis sp. nov., isolated from soil in a location at Jiangsu Province, China, is described and illustrated based on morphological, morphometric and molecular characterizations. The new species is characterized by its body 1.17–1.53 mm long, lip region offset by marked constriction and 12.1–13.8 μm broad, mural tooth deltoid and 9.6–11.7 μm long, neck 278–360 μm long, pharyngeal expansion 164–208 μm long or occupying more than one-half (54–62%) of total neck length, uterus 32.5–35.3 μm long or 1.0–1.1 times the corresponding body diameter, V = 47.8–53.4, paravulvae absent, female tail subcylindrical conoid (30.5–39.5 μm, c = 36.0–45.5, c′ = 1.7–2.2) with widely rounded end, and male unknown. The new species was compared with six known species of the genus including Paravulvus acuticaudatus, Paravulvus confusus, Paravulvus hartingii, Paravulvus iranicus, Paravulvus loofi and Paravulvus microdontus mainly by similarities in having conical tail and c′ value larger than 1.3. The rRNA and mitochondrial cytochrome oxidase subunit 1 genes of the new species were obtained and were used for reconstructing the phylogenetic relationships of the new species.
For a hypersonic-speed aircraft with a flat fuselage structure that has narrow space for a traditional wheel-type landing gear retraction, a novel type of wheel-ski landing gear is designed, which is different from traditional landing gears in force distribution and actuation methods. In order to capture the direction control performance of an aircraft with the wheel-ski landing gear, the aircraft ground taxiing nonlinear dynamic mathematical model is built based on a certain type of aircraft data. The experiment of the wheel-ski landing gear actuator and the differential brake control system is carried out to verify that the electric wheel-ski actuator model with the pressure sensor is in good agreement with the test results, indicating the model validity and the speediness of the differential brake response. Then a new fuzzy combined direction rectifying control law is designed based on the optimisation method and the fuzzy control theory. Comparing with the PD wheel-ski differential brake control, the direction rectifying efficiencies increase higher than 140% during the whole taxiing process. In addition, the combined control law can also decrease the overshoots of the yaw angle responses effectively. Finally, the stability and robustness of the designed combined direction control law are verified under various working conditions.
This paper studied the use of eye movement data to form criteria for judging whether pilots perceive emergency information such as cockpit warnings. In the experiment, 12 subjects randomly encountered different warning information while flying a simulated helicopter, and their eye movement data were collected synchronously. Firstly, the importance of the eye movement features was calculated by ANOVA (analysis of variance). According to the sorting of the importance and the Euclidean distance of each eye movement feature, the warning information samples with different eye movement features were obtained. Secondly, the residual shrinkage network modules were added to CNN (convolutional neural network) to construct a DRSN (deep residual shrinkage networks) model. Finally, the processed warning information samples were used to train and test the DRSN model. In order to verify the superiority of this method, the DRSN model was compared with three machine learning models, namely SVM (support vector machine), RF (radom forest) and BPNN (backpropagation neural network). Among the four models, the DRSN model performed the best. When all eye movement features were selected, this model detected pilot perception of warning information with an average accuracy of 90.4%, of which the highest detection accuracy reached 96.4%. Experiments showed that the DRSN model had advantages in detecting pilot perception of warning information.
As a basic flow model for engineering applications, wall-bounded turbulent flow has been widely studied in the field of aero-optics, but the flow control methods that could effectively suppress aero-optical effects are relatively rare. As an urgent requirement in engineering application, the concept of the steady wall blowing and suction is proposed by the author. Firstly, the author briefly described the flow model and physical method. Secondly, the choice of disturbance type is given. Then, the results of wall blowing-suction, suction and blowing ways based on steady and unsteady disturbance are compared. Finally, it is concluded that employing the high steady wall blowing disturbance (A = 0.2) could realise aero-optical suppression by around 20%. Besides, the steady wall suction scheme contributes to about 70%–80% reduction effect within a wide amplitude range (A = 0.2–1.0), which suppresses this effect by maintaining laminar state downstream contrasted by the baseline case.
We report the experimental results of the commissioning phase in the 10 PW laser beamline of the Shanghai Superintense Ultrafast Laser Facility (SULF). The peak power reaches 2.4 PW on target without the last amplifying during the experiment. The laser energy of 72 ± 9 J is directed to a focal spot of approximately 6 μm diameter (full width at half maximum) in 30 fs pulse duration, yielding a focused peak intensity around 2.0 × 1021 W/cm2. The first laser-proton acceleration experiment is performed using plain copper and plastic targets. High-energy proton beams with maximum cut-off energy up to 62.5 MeV are achieved using copper foils at the optimum target thickness of 4 μm via target normal sheath acceleration. For plastic targets of tens of nanometers thick, the proton cut-off energy is approximately 20 MeV, showing ring-like or filamented density distributions. These experimental results reflect the capabilities of the SULF-10 PW beamline, for example, both ultrahigh intensity and relatively good beam contrast. Further optimization for these key parameters is underway, where peak laser intensities of 1022–1023 W/cm2 are anticipated to support various experiments on extreme field physics.
Surgical management is the mainstay of treatment for tumours in the parapharyngeal space. This study aimed to evaluate the indications, limits and technical nuances of the endoscopic transoral approach.
Thirteen patients with parapharyngeal space tumours that were treated between May 2017 and November 2020 were included in this retrospective study.
All patients underwent surgery for complete oncological resection except one patient who received treatment for diagnostic purposes. No major complications were reported, with excellent control of the vital structures of the parapharyngeal space.
The endoscopic transoral approach to the parapharyngeal space is a promising alternative approach for selected parapharyngeal space tumours with satisfactory outcomes.
To summarise and describe the clinical presentations, diagnostic approaches and airway management techniques in children with laryngotracheal trauma.
The clinical data related to laryngotracheal trauma diagnosed and treated at the Beijing Children's Hospital, between January 2013 and July 2018, were retrospectively reviewed. Disease diagnosis, treatment, management and outcomes were analysed.
A total of 13 cases were enrolled, including 7 cases of penetrating laryngotracheal trauma. The six cases of blunt laryngotracheal trauma were caused by collisions with hard objects. In all cases, voice, airway and swallowing outcomes were graded as ‘good’, except for one patient who had residual paralysis of the vocal folds.
Flexible fibre-optic laryngoscopy and computed tomography can play an important role in diagnosing laryngotracheal trauma. The airway should be secured and, if necessary, opened by tracheal intubation or tracheostomy.
This study aimed to investigate the association of nasal nitric oxide and olfactory function.
A cross-sectional study was performed in 117 adults, including 91 patients with chronic rhinosinusitis and 26 healthy controls. Scores on the 22-item Sino-Nasal Outcomes Test, Lund-Mackay scale and Lund-Kennedy scale were recorded to assess severity of disease. All participants were screened for common inhaled and food allergens. Nasal nitric oxide and fractional exhaled nitric oxide testing, acoustic rhinometry and anterior rhinomanometry testing were performed to measure nasal function. The validated Sniffin’ Sticks test battery was used to assess olfactory function.
Higher nasal nitric oxide was an independent protective factor for odour discrimination and odour threshold in participants with chronic rhinosinusitis after adjusting for age, gender, drinking, smoking, 22-item Sino-Nasal Outcomes Test, Lund-Mackay score, Lund-Kennedy score, immunoglobulin E and the second minimal cross-sectional area by acoustic rhinometry. Nasal nitric oxide also showed high discrimination in predicting impaired odour discrimination. In addition, nasal nitric oxide was lower in older participants, those with higher Lund-Mackay or Lund-Kennedy scores and higher with elevated total serum immunoglobulin E concentrations above a threshold of 0.35 kU/l.
Higher nasal nitric oxide is associated with better odour discrimination in chronic rhinosinusitis and is modulated by age, degree of allergy and severity of chronic rhinosinusitis.