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Abstract This study aimed to investigate the association between serum chloride levels and all-cause mortality in critically ill patients with chronic obstructive pulmonary disease (COPD). Data from the Medical Information Mart for Intensive Care IV (MIMIC-IV) database were extracted for analysis. Demographic information, laboratory results, medical histories, vital signs, and prognosis-related data were collected. Cox proportional hazard models were used to assess the relationship between serum chloride levels and 90-day and 365-day mortality. Subgroup analyses were conducted to explore potential interactions between serum chloride levels and various factors. The study included patients with a median age of 72.00 years, of whom 52.39% were male. Higher quartiles of serum chloride levels were associated with significantly lower levels of weight, RBC, platelet, hemoglobin, and other variables (P

Abstract There are few studies on the relationship between dietary habits and asthma–COPD overlap (ACO). In this study, we aimed to investigate the association between dietary inflammation index (DII) score and ACO. Data from the National Health and Nutrition Examination Survey (NHANES) from 1999 to 2020. The DII score was first calculated and the demographic characteristics of the grouping based on the DII quartile were assessed. The weighted logistic regression model was used to study the relationship between DII and ACO. Subgroup analysis was used to further explore the differences in different subgroups. Restricted cubic spline (RCS) plot was used to show the general trend of DII score and disease risk, and threshold effect analysis was used to determine the inflection point. In a comparison of baseline characteristics, the highest ACO prevalence was found in the fourth quartile array of people in DII. An adjusted weighted logistic regression model showed that DII was positively correlated with the incidence of ACO. Subgroup analysis showed that the association was more pronounced in women, non-Hispanics, people with cardiovascular disease, and people without diabetes. The RCS graph shows that overall, the risk of ACO increases with the increase of DII score. Threshold effect analysis showed that the inflection point was 3.779, and the risk was more significant after the DII score was greater than the inflection point value (OR 2.001, 95% CI 1.334–3.001, P

This paper considers the maneuvering penetration methods of missile which do not know the intercepting strategies of the interceptor beforehand. Based on reinforcement learning, the online intelligent maneuvering penetration methods of missile are derived. When the missile is locked by the interceptor, in terms of the tracking characteristics of the interceptor, the missile carries out tentative maneuvers which lead to the interceptor makes the responses respectively, in the light of the information on interceptor responses which can be gathered by the missile-borne detectors, online game confrontation learning is employed to increase the miss distance of the interceptor in guidance blind area by reinforcement learning algorithm, the results of which are used to generate maneuvering strategies that make the missile to achieve the successful penetration. The simulation results show that, compared with no maneuvering methods or random maneuvering methods, the methods proposed not only present higher probability of successful penetration, but also need less overload and lower command switching frequency. Moreover, the effectiveness of this maneuvering penetration methods can be realized under the condition of limited number of training.

ObjectivesWith increasing congestion and interference facing shipborne wireless communication equipment, it is urgent for antennae functions to be reconstructed. This study proposes a microstrip Quasi-Yagi antenna with a continuously reconfigurable cross-band frequency function. MethodsFirst, PIN diodes are loaded on the quasi-Yagi antenna, and multi-band multi-mode switching is realized by controlling turning the diodes on/off. Second, by attaching snowflake split-ring resonator (SRR), the antenna gains two stable frequency resonance points and a stable radiation azimuth. ResultsAccording to the simulation and measurement results, the antenna realizes frequency reconfiguration in the C-band (5.77–7.10 GHz and 7.40–7.56 GHz) and X-band (8.33–8.64 GHz and 8.76–9.27 GHz). Its radiation pattern can stably point in the direction of capacitive loading conduction, with gain above 5.7 dBi at each frequency and an average 3 dB beamwidth value of 102°. ConclusionsBy loading PIN diodes on the antenna and attaching a snowflake SRR, cross-band frequency becomes frequency reconfigurable, and beam deflection with low error is achieved, thereby improving the spectral utilization of ship systems and avoiding coupling interference between multiple antennae.

Abstract All‐small‐molecule organic solar cells (all‐SM OSCs), with p‐type small molecule (p‐SM) as donor and n‐type small molecule (n‐SM) as acceptor, have drawn intensive research interests in recent years. All‐SM OSCs show advantages to their polymer counterparts, including well‐defined chemical structure, easy purification, and better repeatability in devices. The highest power conversion efficiency (PCE) of all‐SM OSCs has increased quickly to over 15% nowadays. In this review, we just summarize the progress of non‐fullerene all‐SM OSCs (NF all‐SM OSCs) in recent five years, by dividing small‐molecule donors into four categories based on the molecular segments of oligothiophene, benzo[1,2‐b:4,5‐b’]dithiophene (BDT) trimer, typical BDT‐central unit connected with π‐bridges of thiophene or electron deficient acceptor units. We aim to illustrate the relationship of molecular structures, properties, and device performance of small‐molecule donors with those different molecular segments. Furthermore, the tendency of molecular design for photo‐active materials are also depicted and summarized. Finally, we give our views on the future prospects of NF all‐SM OSCs to design the next‐generation OSCs.

The pattern reconfigurable antenna provides a new implementation scheme for expanding application in modern wireless communications. In this paper, a pattern-reversal wideband microstrip antenna is proposed. This antenna is composed of a radiation patch with attached rectangular metal rings connected by a microstrip line on the upper layer and a four-defects ground plane connecting two PINdiodes- loaded L-shaped stubs on the bottom layer. In view of the Yagi-antenna feature of metal rings and L-shaped stubs, the ON-OFF of diodes controls directly the radiation direction of antenna. Under the joint action of multiple resonances of rings, slots and stubs, the bandwidth of antenna is surged so as to develop evident wideband radiation. Finally, the measured impedance bandwidth of −10 dB is about 20.1% from 4.54 to 5.55 GHz. The average gain of the antenna with the size of $0.75 \lambda_{0} \times 0.75 \lambda_{0}$ reaches 4.92 dBi. With the diodes dependence, the pattern can really deflect in opposite direction. The designed antenna has much advantages, such as low cost, wider band, compact and simple structure along with explicit application scenarios.

Abstract Background C-Myc overexpression is associated with poor prognosis and aggressive progression of natural killer/T-cell lymphoma (NKTCL). Matrine, a main alkaloid of the traditional Chinese herb Sophora flavescens Ait, has been shown to inhibit cellular proliferation and induce apoptosis of various cancer cells. The present study investigated the effects and possible mechanisms of matrine inhibiting the growth of natural killer/T-cell lymphoma cells. Methods The effects of matrine on the proliferation, apoptosis and expression of apoptotic molecules, STAT3, LMP1, RUNX3, EZH2 and activation of CaMKIIγ/c-Myc pathway were examined in cultured NKTCL cell line NK92 cells. Results In cultured NK92 cells, matrine inhibited the proliferation in a dose and time dependent manner. The IC50 value of matrine was 1.71 mM for 72 h post exposure in NK92 cells. Matrine induced apoptosis with decreased Bcl-2 expression and the proteasome-dependent degradation of c-Myc protein in NK92 cells. c-Myc protein half-life in NK92 was reduced from 80.7 min to 33.4 min after matrine treatment, which meant the stability of c-Myc was decreased after matrine exposure. Furthermore, we found that matrine downregulated c-Myc phosphorylation at Ser62 together with the inhibition of CaMKIIγ, a key regulator of c-Myc protein in NKTCL. The downregulation of c-Myc transcription by matrine was mediated through LMP1 inhibition. We also observed that anti-proliferative activity of matrine was irrelevant to STAT3, RUNX3 and EZH2. Conclusions The results of the present study indicated that matrine inhibits the growth of natural killer/T-cell lymphoma cells by modulating LMP1-c-Myc and CaMKIIγ-c-Myc signaling pathway.

A compound aircraft with a collectible rotor has the ability of vertical take-off and landing (VTOL), high-speed flight and long-range cruising. Compared to systems in other compound aircraft, the collectible rotor can work as a conventional rotor in helicopter mode and can be gathered into a disk in the center in fixed-wing mode, thereby relieving the rotor's limitations pertaining to forward flight performance. The collectible rotor is a key component in the design and realization of a compound aircraft. Based on a 35-kg-level prototype, in this study, the principle of a folding rotor is proposed, a dynamic model of the rotor is established considering the complex nonlinear compound motion of rotation and folding, and the aerodynamic and dynamic characteristics are analyzed considering the coupling of different speeds of the rotor and folding strategies for the folding process. According to the above research, a complete rotor system, including an unconventional rotor structure, closed-loop real-time control system, and high-torque driving system, is designed. A demonstration model was constructed to verify the feasibility of the folding rotor. Finally, through an on-board test, the folding rotor system was verified in a simulated real flight state. This paper provides a theoretical basis for folding rotor design and proposes a set of design methods and research concepts. [ABSTRACT FROM AUTHOR]

This study used the discrete element method (DEM), which is effective and popular for solving the problem of granular systems simulating the motion of particles in a ball mill in different structural forms and at different rotational speeds. Firstly, simulations of five kinds of lifters (triangular, trapezoidal, rectangular, ladder and hemispherical) were set up. The results were as follows: when the rectangular lifter was selected as mill liner, the ball mill efficiency was significantly high. The breaking performance of the hemispherical lifter and the ladder lifter was poor, because the main pattern of motion was grinding rather than impact breakage. Secondly, the effects of the height-width ratio of the rectangular lifter, the height of the lifter and the number of lifters on the working efficiency of the ball mill were studied. It was found that a number of rectangular lifters of 12 and a height-width ratio of 3:1 produced the best results. The best height of the rectangular lifter was about 13 mm. Lastly, displacement, stress and deformation were analyzed using DEM coupled with a finite element method (FEM). The purpose was to design the geometrical lifter structure and to improve the performance of the ball mill. [ABSTRACT FROM AUTHOR]