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Unmanned aerial vehicles (UAVs), due to their mobility and flexibility, are widely used in tasks such as search and tracking. The large amount of data generated during task execution can be significantly leveraged by machine learning (ML) algorithms to improve the intelligence of UAV clusters. Federated learning (FL), as a distributed machine learning architecture, is more suitable for UAV networks with limited bandwidth and energy budget, as it only requires model parameter transmission during training. To fully exploit the advantages of FL in UAV networks, this paper models factors affecting training energy consumption, such as bandwidth, computational frequency, FL accuracy, and training delay. A joint optimization algorithm is proposed to minimize the overall training energy consumption of FL by jointly optimizing training parameter settings, UAV trajectories, resource allocation of communication and computation in UAV networks. The proposed joint optimization algorithm decomposes the mixed integer nonlinear integer programming problem (MINLP) into three sub-problems, and transforms the non-convex sub-problems into convex sub-problems through methods such as successive convex approximation (SCA) and block coordinate descent to obtain suboptimal solutions. Simulation results show that, based on the constraints of training accuracy, UAV movement, and FL delay, the proposed algorithm reduces the overall training energy consumption of unmanned aerial vehicles by more than 15% compared to the existing joint training and resource optimization schemes. [ABSTRACT FROM AUTHOR]

It is necessary to measure the situation of extinguishing agent concentration along with time in the ground simulation test of helicopter/airplane powerplant. The principle that the different percentage of agent in the air has different flow resistances when these agents passing through some porous plug is used, the relation of agent concentration and flow resistance is researched and confirmed by the calibration. The special extinguishing agent concentration measurement is developed, and used in the ground simulation test of several helicopters. The results show that, the measurement has sensitive response, can reflect the varying situation of extinguishing agent concentration in real-time, and satisfy the requirement of ground simulation test in the fire extinguisher system of helicopter/airplane powerplant.

The paper reviewed the research progress in the modification methods of polyacrylonitrile materials in recent years, which include copolymerization modification, graft modification, blending modification, finishing method, and plasticization modification. The characteristics of different modification methods were analyzed, and the modification research direction and future development trends of polyacrylonitrile materials were prospected. [ABSTRACT FROM AUTHOR]

The permeation theory of small gas molecules and gas barrier model were introduced. The preparation methods of gas barrier graphene/polymer composites and the characterization methods of gas barrier properties were reviewed. The main factors affecting the gas barrier properties of the graphene/polymer composites and the corresponding improvement measures were analyzed and summarized. The future research directions were also prospected. [ABSTRACT FROM AUTHOR]

In order to improve the capillary limit of surface structures for enhancing capillary-fed film boiling heat transfer, the microgroove arrays overlaid with microparticle structures were fabricated on titanium substrates by taking advantages of melting and solidification, and phase explosion of nanosecond pulsed lasers. A modified capillary liquid transport characteristic coefficient was developed to characterize the capillary liquid transport capability of the fabricated microgrooves based on flow resistance in open microgrooves model. The results show that the microparticle structures obtained during laser ablation improve the superhydrophilicity as well as the capillary liquid transport capability. The capillary coefficient increases with the decrease of the microgroove width. Moreover, the capillary limit may be further increased by fabricating minor microgrooves at the bottom of the major microgrooves with unique layered capillary transport configuration in imitation of sarracenia trichome. [ABSTRACT FROM AUTHOR]

With the experiment of fuel system undergoing the boost fueling to self-suck, the study on history rate of fuel flow is conducted. Based on the experimental study and the analysis of operational principle of transient process of helicopter fuel system transferred from boost fueling to self-suck, a simulation model of helicopter fuel system is built with commercial code of Flowmaster. The simulation results and the experimental results are in a good agreement, which reveals the validity of numerical model. By combining with simulation results, the impact of check valve spring preload and spring rate on engine inlet pressure and flow rate is analyzed. Consequently, the reference of components of fuel system is provided. [ABSTRACT FROM AUTHOR]

Objective: This study aimed to explore the differences in esophageal pressure at different ages, and to analyze the possible age inflection points of the physiological degeneration of esophageal motility, and to further evaluate whether the degeneration of esophageal kinetics with age is the only risk factor for the occurrence of throat reflux disease （LPRD）. Methods: A solid-state high-resolution esophageal pressure measurement was performed on 41 volunteers without throat symptoms. The Chicago classification data were compared with the manometry results of all volunteers. In addition, the esophageal manometry results were compared among groups with pre-set age inflection point. Results: Most of the volunteers' esophageal pressure measurements were in line with Chicago standards. When the inflection point of age was 55 years, no significant difference was found between the two groups. However, when the inflection point of age was 65 years, a significant difference in the length of the upper esophageal sphincter and the contractile front velocity was found between the two groups（ P =0.021 and 0.046 respectively）. Conclusion: Esophageal dynamics was weakened with increasing age in the volunteers without laryngopharyngeal symptoms, which was more obvious after the age of 65, but still within the normal range. The degeneration of esophageal motility is not the only risk factor for LPRD., Competing Interests: The authors of this article and the planning committee members and staff have no relevant financial relationships with commercial interests to disclose., (Copyright© by the Editorial Department of Journal of Clinical Otorhinolaryngology Head and Neck Surgery.)

Cancer therapy with accelerated proton or heavy ion beam is the most advanced radiotherapy technology, which is recognized by the international community at present. It is of great practical significance to study the medical proton and heavy ion accelerators and the radiotherapy technology, in order to promote the development of the advanced medical radiotherapy equipments and improve the quality of life of cancer patients in China. After a brief overview of cancer therapy with proton and heavy ion beam, this paper summarized and analyzed the application status of medical proton accelerators and medical heavy ion accelerators at home and abroad, and finally put forward the future development trends of medical proton and heavy ion accelerators and the radiotherapy technology, it can provide a reference for the progress and development strategies of the advanced radiotherapy equipments in China.

Objective: To compare the clinical effects between continuous renal replacement therapy (CRRT) and intermittent haemodialysis (IHD) for the treatment of sepsis-induced acute kidney injury (AKI)., Methods: A prospective study was conducted. Seventy-three patients with sepsis-induced AKI admitted to the intensive care units (ICUs) of Tianjin Hospital and Tianjin First Center Hospital from January to December in 2014 were enrolled. They were randomly divided into two groups: CRRT group (n = 35) and IHD group (n = 38). Data were recorded for the patients in two groups before treatment, including acute physiology and chronic health evaluation Ⅱ (APACHE Ⅱ) score, mean arterial pressure (MAP), urine volume, and the levels of C-reactive protein (CRP) and serum creatinine (SCr) before and 1 week after treatment, the time of recovery of urine volume, the length of ICU stay, the duration of organ support, and the incidence of cardiovascular events., Results: There was no statistically significant difference in APACHE Ⅱ scores (21.63±2.46 vs. 21.34±2.46), MAP [mmHg (1 mmHg = 0.133 kPa): 71.26±10.70 vs. 75.74±15.17], urine volume (mL: 404.00±79.13 vs. 438.97±87.17), CRP (mg/L: 100.94±14.73 vs. 95.17±27.03), and SCr (μmol/L: 394.02± 50.26 vs. 390.47±54.42) before treatment between CRRT group and IHD group (all P > 0.05). One week after treatment, compared to the IHD group, CRRT could dramatically reduce the levels of CRP (mg/L: 41.05±10.15 vs. 60.21±14.78, t = 6.401, P < 0.001), SCr (μmol/L: 185.97±65.48 vs. 232.02±71.93, t = 2.862, P = 0.006), urine output recovery time (days: 7.94±3.06 vs. 11.08±3.71, t = 3.923, P < 0.001), the length of ICU stay (days: 9.54±3.39 vs. 13.42±3.89, t = 4.521, P < 0.001), organ support time (days: 3.23±2.70 vs. 6.34±3.36, t = 4.343, P < 0.001), and the incidence of cardiovascular events [23.53% (8/35) vs. 39.47% (15/38), χ2 = 5.509, P = 0.025]., Conclusion: Compared to IHD, CRRT can more efficiently help patients with sepsis-induced AKI in removing excessive water, metabolic waste, and lower the levels of pro-inflammatory cytokines, maintain homeostasis of the internal environment, lower the adverse effects on cardiovascular system, so that it significantly improve the prognosis of patients, shorten the time of organ support and the length of ICU stay.

Objective: This study aimed to screen high-performance ammonia oxidizing bacteria ( AOB) resistant to a high concentration of ammonia-nitrogen and low C/N ratio, for the development of novel AOB agents., Methods: Multi-point sampling, compulsory domestication, gradient dilution of domestication liquid were conducted to screen AOB with efficient and stable ammonia-nitrogen removing ability, and effects of different factors on its ammoxidation ability including C/N ratio, shaking speed and ammonia-nitrogen concentration were studied. Dominant strains were screened and identified by morphological observation, physiological and biochemical properties test and 16S rRNA sequence analysis., Results: Three efficient AOB were obtained, among them a micro-flora named JQ8 showed the highest activity. The ammonia-nitrogen removal rate reached 95. 07% in a simulated wastewater with 17. 86 mmol/L of initial ammonia-nitrogen at C/N 4 treated by JQ8 for 6 days. Moreover, its ammonia nitrogen removal rate kept above 95% and net nitrogen removing rate nearly 80% in the solution with a C/N ratio above 4 and an NH₄⁺-N concentration below 28.57 mmol/L. The circuit board industry wastewater was treated using the laboratory-simulated aerobic active sludge disposal system. The removal rate of NH₄⁺-N and total nitrogen reached 87.8% and 67.6% respectively after 7 days' treatment using JQ8. Defluvibacter sp., Paracoccus sp. and Aquamicrobium sp. were identified as the dominant strains after the composition analysis of JQ8., Conclusion: An ammonia oxidizing bacteria consortium JQ8 screened from the landfill leachate showed a strong ammonium-nitrogen removal and endurance ability under low C/N ratio and high ammonia-nitrogen concentration, thus is probably applicable to intensify the ammonia-nitrogen removal treatment of industrial wastewater with sewage disposal system.

Objective: To assess the efficacy and adverse reaction of nasal packing materials Rapid Rhino and Merocel., Method: We searched the database PubMed, EMBASE, Cochrane Library, CBM, CNKI, VIP and WANFANG database on line by computer, and traced the related references. Randomized controlled trials(RCTs) of rapid rhino and merocel as nasal packing materials were included. The quality of the included documents was evaluated by the criterion of Cochrane handbook 5.1. The cochrane collaboration's Revman 5.1 software was used for data analysis., Result: Four RCTs involving 115 patients were identified. Meta-analyses showed that Rapid Rhino produced significantly lower pain and discomfort during insert of pack [MD = 1.37, 95% CI (0.13, 2.60), P < 0.05], whereas less pain and discomfort during removal of pack [MD = 2.88, 95% CI (2.34, 3.41), P < 0.01]. Rapid Rhino associated with a significantly slighter degree of fullness raised after insertion [MD = 1.15, 95% CI (0.75, 1.55), P < 0.01, and the same situation happened after 6 hours [MD = 1.15, 95% CI (0.75, 1.55), P < 0.01]. Rapid rhino caused to less reactionary bleeding when pack removal [MD = 0.26, 95% CI (0.12, 0.39), P < 0.01], rapid rhino was easier for the healthcare worker during insert and removal. There was no significant difference between two packs on the efficiency of hemostatic [OR = 1.00, 95% CI (0.38, 2.61), P > 0.05]., Conclusion: The application of Rapid Rhino caused less pain and fullness, leaded to slighter bleed than Merocel when insertion and removal. There was no significant difference between two packs on the efficiency of hemostatic when used for epistaxis or after routine nasal surgery.

Objective: Denitrifying bacteria play an important role in the biological nitrogen removal process, especially the aerobic denitrifying bacteria. However, there are few studies on aerobic denitrifying bacteria. The present study aimed at the isolation of aerobic denitrifying bacteria with high ammonium and nitrite nitrogen removing ability from environmental samples, and its phylogeny and denitrifying characteristics., Methods: Based on the aerobic denitrifying activity, ammonium and nitrite nitrogen removing ability, the strains were isolated from sludge, water and sediment in a eutrophicated pond. A strain with the highest activities was identified according to its morphological, physiological and biochemical properties and phylogenetic analysis of its 16S rRNA sequence. By using NO(3-)-N, NH(4+)-N and NO(2-)-N as the sole nitrogen source respectively, its denitrifying characteristics, and the effects of culture conditions such as initial pH of medium, temperature, carbon source, shaking speed on the ability of removing ammonium and nitrite nitrogen, were investigated under aerobic condition., Results: Among the isolated strains, strain C-4 showed the highest ability of removing ammonium and nitrite nitrogen. Strain C-4 was identified as Acinetobacter sp.. Under the conditions of sodium citrate as carbon source, temperature 30 degres C, shaking speed 120 r/min, cell age of 18 h, pH 8.5 for 200 mg/L NH(4+)-N medium and pH 7.5 for 100 mg/L NO(2-)-N medium, the net removal efficiency of nitrogen were 65.8% and 47.8% after 15 h and 12 h, respectively., Conclusion: An aerobic denitrifying strain Acinetobacter sp. C-4 (HQ896038) was isolated from water pond, and it exhibited high net removal efficiency of nitrogen in relative media. The net removal efficiency of nitrogen of strain C-4 was 73.04% in dealing with a eutrophicated pond water.