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Abstract Background As a kind of emerging contaminant, psychoactive substances (PSs) have been detected in different types of freshwater ecosystems; however, their occurrence in coastal shore areas is seldom reported. In this study, surface water samples from the mangrove ecosystems across 6 cities and counties in Hainan Island, 68 water samples were collected from August to December 2022, for assessment of the occurrence, spatial distribution, and potential ecological risks of PSs in the mangrove ecosystem in Hainan Island, South China. Results A total of 13 PSs were determined by liquid chromatography–mass spectrometry (LC–MS), with 7 of them at high frequency (> 50%). Amphetamine (AMP) was detected with the highest concentration of 12.0 ng/L, followed by ephedrine (EPH) of 8.31 ng/L. The spatial distribution showed that PSs concentrations in mangroves in the Eastern Route were higher than those in the Western Route, similar to the level of regional development, which may be influenced by seasonal tourism. The risk quotients (RQs) of the PSs ranged from 0 to 0.0055, suggesting the low risk of PSs in Hainan mangrove ecosystems. Conclusions Generally, this study provided valuable insights into the environmental occurrence, spatial variations, and ecological risks of PSs in mangrove wetlands systems for the first time, serving as a foundation for understanding their influence on the mangrove ecosystem, which may aid in protection of those unique and vulnerable areas.

BackgroundAnticoagulants are the primary means for the treatment and prevention of venous thromboembolism (VTE), but their clinical standardized application still remains controversial. The present study intends to comprehensively compare the efficacy and safety of various anticoagulants in VTE.MethodsMedline, Embase, and Cochrane Library from their inception up to August 2023 were searched to compare the efficacy and safety of various anticoagulants in VTE. We extracted data on study settings, baseline characteristics, interventions, and outcomes, applying the intention-to-treat principle. Two researchers assessed study bias using the Cochrane tool, resolving disagreements through discussion or third-party adjudication. Network meta-analyses were performed based on Bayesian generalized linear models, and a frequentist framework with multivariate random effects was used to fit the model.ResultsIn terms of treatment, 58 trials with 119,417 patients proved eligible, while 125 trials with 225,414 patients were included in terms of prevention. All anticoagulants were found to reduce the recurrence or incidence of VTE compared with Placebo, of which high-level evidence indicated that direct thrombin inhibitors (TIs) and novel oral anticoagulants (NOACs) were the two most effective drugs. For treatment, low molecular weight heparin (LMWH), unfractionated heparin (UFH), and vitamin K antagonists (VKAs) significantly increased the risk of major bleeding in comparison to Placebo. For prevention, only UFH (OR 2.0, 95% CI 1.2–3.3) and NOACs (OR 1.8, 95% CI 1.2–2.6) showed significant increased risks in major bleeding. Additionally, after an exhaustive analysis of NOACs, analysis showed that apixaban (RR 0.5, 95%CI 0.17–1.46) had a superior performance in major bleeding compared to rivaroxaban (RR 3.87, 95%CI 1.48–10.09).ConclusionTIs and NOACs were superior in efficacy with minimal side effects, making them pivotal choices for both prevention and treatment of VTE. Clinical practitioners must carefully weigh drug characteristics, indications, and contraindications to optimize treatment outcomes.Systematic Review Registrationhttps://www.crd.york.ac.uk/PROSPERO/display_record.php?RecordID=466775.

Abstract Background Despite the use of targeted therapeutic approaches, T-cell acute lymphoblastic leukemia (T-ALL) is still associated with a high incidence of complications and a poor prognosis. Indisulam (also known as E7070), a newly identified molecular glue compound, has demonstrated increased therapeutic efficacy in several types of cancer through the rapid degradation of RBM39. This study aimed to evaluate the therapeutic potential of indisulam in T-ALL, elucidate its underlying mechanisms and explore the role of the RBM39 gene. Methods We verified the anticancer effects of indisulam in both in vivo and in vitro models. Additionally, the construction of RBM39-knockdown cell lines using shRNA confirmed that the malignant phenotype of T-ALL cells was dependent on RBM39. Through RNA sequencing, we identified indisulam-induced splicing anomalies, and proteomic analysis helped pinpoint protein changes caused by the drug. Comprehensive cross-analysis of these findings facilitated the identification of downstream effectors and subsequent validation of their functional roles. Results Indisulam has significant antineoplastic effects on T-ALL. It attenuates cell proliferation, promotes apoptosis and interferes with cell cycle progression in vitro while facilitating tumor remission in T-ALL in vivo models. This investigation provides evidence that the downregulation of RBM39 results in the restricted proliferation of T-ALL cells both in vitro and in vivo, suggesting that RBM39 is a potential target for T-ALL treatment. Indisulam’s efficacy is attributed to its ability to induce RBM39 degradation, causing widespread aberrant splicing and abnormal translation of the critical downstream effector protein, THOC1, ultimately leading to protein depletion. Moreover, the presence of DCAF15 is regarded as critical for the effectiveness of indisulam, and its absence negates the ability of indisulam to induce the desired functional alterations. Conclusion Our study revealed that indisulam, which targets RBM39 to induce tumor cell apoptosis, is an effective drug for treating T-ALL. Targeting RBM39 through indisulam leads to mis-splicing of pre-mRNAs, resulting in the loss of key effectors such as THOC1.

Abstract Real‐time monitoring of the coal caving process in fully mechanized mining is crucial for achieving intelligent and efficient top‐coal caving. While the coal gangue identification method, employing vision and deep learning, has advanced in the realm of intelligent monitoring, it exhibits a dependency on high‐performance hardware. This reliance poses challenges for deploying identification equipment on mobile terminals, hindering the widespread application of this method. To address the issues above, the paper presents a lightweight algorithm, utilizing You Only Look Once version 5s (YOLOv5s), utilizing YOLOv5s for the real‐time perception of the top‐coal caving state in fully mechanized caving mining. We replace the backbone network of YOLOv5s with the ShuffleNetv2 structure that is more suitable for lightweight deployment, and add the Simple Attention Mechanism attention mechanism to the network structure to enhance the model's receptive field and feature expression ability, and reduce the impact of falling debris on the detection results. A dynamic experimental platform for top‐coal caving in fully mechanized caving mining for thick coal seams is set up, and preprocessing operations such as brightness, sharpening, and denoising are performed on the image data sets collected by high‐speed industrial cameras. Research results show that compared with the traditional YOLOv5s, the improved model's P, mAP, F1 score, and other indicators have increased by 3.4%, 2.1%, and 1.1%, respectively, the model size is 70% of the original, and the detection frames per second value has increased by 48.1%. The lightweight algorithm stabilizes the accuracy of coal gangue identification dramatically in real time. It dramatically reduces the computing pressure on the mobile terminal, providing basic theory and practice for real‐time monitoring of fully mechanized coal caving mining.

The ambient air quality standard (AAQS) is a vital policy instrument for protecting the environment and human health. Hainan Province is at the forefront of China's efforts to protect its ecological environment, with an official goal to achieve world-leading air quality by 2035. However, neither the national AAQS nor the World Health Organization guideline offers sufficient guidance for improving air quality in Hainan because Hainan has well met the former while the latter is excessively stringent. Consequently, the establishment of Hainan's local AAQS becomes imperative. Nonetheless, research regarding the development of local AAQS is scarce, especially in comparatively more polluted countries such as China. The relatively high background values and significant interannual fluctuations in air pollutant concentrations in Hainan present challenges in the development of local AAQS. Our research proposes a world-class local AAQS of Hainan Province by reviewing the AAQS in major countries or regions worldwide, analyzing the influence of different statistical forms, and carefully evaluating the attainability of the standard. In the proposed AAQS, the annual mean concentration limit for PM2.5, the annual 95th percentile of daily maximum 8-h mean (MDA8) concentration limit for O3, and the peak season concentration limit for O3 are set at 10, 120, and 85 μg/m3, respectively. Our study indicates that, with effective control policies, Hainan is projected to achieve compliance with the new standard by 2035. The implementation of the local AAQS is estimated to avoid 1,526 (1,253–1,789) and 259 (132–501) premature deaths attributable to long-term exposure to PM2.5 and O3 in Hainan in 2035, respectively.

Straw returning (R) combined with the application of a decomposition agent (RD) can increase crop yield and soil carbon (C) storage. However, the effect of RD on soil nitrous oxide (N2O) emissions in tropical areas remains poorly understood. In this study, an in situ experiment was performed under different water management strategies (long-term flooding or alternate wetting and drying) with the R and RD treatments to evaluate soil N2O emissions and rice yield. The SOC and TN contents were significantly lower under the RD treatment than under the R treatment. The R treatment significantly increased rice yield; however, the yield was further significantly increased under the RD treatment. The soil N2O emissions and yield-scaled N2O emissions were higher under the R treatment than under the no-straw-returning treatment. However, the RD treatment greatly reduced soil N2O emissions and yield-scaled N2O emissions under various water management strategies compared with those under the R treatment. Moreover, yield-scaled N2O emissions were lower in the RD treatment than in the control. The soil N2O emissions and yield-scaled N2O emissions were distinctly higher under alternate wetting and drying than under long-term flooding. Our results indicated that long-term flooding and straw returning with decomposition agents can effectively increase rice yield and reduce soil N2O emissions in tropical areas.

The China–Russia crude oil pipeline (CRCOP) operates at a temperature that continuously thaws the surrounding permafrost, leading to secondary periglacial phenomena along the route. However, the evolution and formation mechanisms of these phenomena are still largely unknown. We used multi-temporal airborne light detection and ranging (LiDAR), geophysical, and field observation data to quantify the scale of ponding and icing, capture their dynamic development process, and reveal their development mechanisms. The results show that the average depth of ponding within 5 m on both sides of the pipeline was about 31 cm. The volumes of three icings (A–C) above the pipeline were 133 m3, 440 m3, and 186 m3, respectively. Icing development can be divided into six stages: pipe trench settlement, water accumulation in the pipe trench, ponding pressure caused by water surface freezing, the formation of ice cracks, water overflow, and icing. This study revealed the advantages of airborne LiDAR in monitoring the evolution of periglacial phenomena and provided a new insight on the development mechanisms of the phenomena by combining LiDAR with geophysics and field observation. The results of our study are of great significance for developing disaster countermeasures and ensuring the safe operation of buried pipelines.

Abstract Background The adverse effects of cardiopulmonary bypass during open cardiac surgery, including hemodilution, seem to be inevitable, especially for patients who generally have a relatively lower BMI with relatively small blood volumes. This study reports the modification and use of a cardiopulmonary bypass (CPB) system to reduce priming volume and hemodilution. Methods This is a retrospective study of 462 adult patients who underwent cardiac valve replacement surgery from January 2019 to September 2021 at the General Hospital of Western Theater Command. The modified group consisted of 212 patients undergoing modified CPB. The control group included 250 patients receiving conventional CPB. Evaluated indices included fluid intake and output volumes during CPB, intraoperative indices related to CPB operation, usage of blood products during the peri-CPB period, and postoperative outcomes. Results The modified group displayed a significant reduction in the crystalloid (200 mL vs. 600 mL, P

Prefabricated building construction has emerged as a transformative technology in construction engineering and the building industries. However, owing to its research characteristics, the relevant literature on prefabricated buildings is diverse and fragmented. This study offers a comparative review of relevant 21st century literature on prefabricated buildings using VOSviewer1.6.18 software. The research progress and future opportunities about prefabricated buildings were comprehensively analyzed, which provides recommendations for its subsequent development. Through keyword searches on the Web of Science, 3214 documents were identified, and an overall analysis of co-citations and co-authorship was conducted. Additionally, a comparative co-occurrence analysis highlighted the differences between China and other countries. Further elaboration of research hotspots is provided, and three future research directions are proposed: (1) energy conservation and reducing the environmental impact of prefabricated buildings, (2) improving the performance of prefabricated building components, and (3) deepening the understanding of the behavior of prefabricated structures under seismic and dynamic conditions. This study provides practitioners and scholars in the field of construction engineering with a comprehensive overview of the literature on prefabricated buildings and paves the way for future advancements in the industry. The findings of this study can be used to promote prefabricated buildings in the architecture, engineering, and construction industries.

Abstract Inorganic perovskite quantum dots CsPbX3 (X = Cl, Br, and I) has recently received extensive attention as a new promising class of X‐ray scintillators. However, relatively low light yield (LY) of CsPbX3 and strong optical scattering of the thick opaque scintillator film restrict their practical applications for high‐resolution X‐ray microscopic imaging. Here, the Ce3+ ion doped CsPbBr3 nanocrystals (NCs) with enhanced LY and stability are obtained and then the ultrathin (30 µm) and transparent scintillator films with high density are prepared by a suction filtration method. The small amount Ce3+ dopant greatly enhances the LY of CsPbBr3 NCs (about 33 000 photons per MeV), which is much higher than that of bare CsPbBr3 NCs. Moreover, the scintillator films made by these NCs with high density realize a high spatial resolution of 862 nm thanks to its thin and transparent feature, which is so far a record resolution for perovskite scintillator‐based X‐ray microscopic imaging. This strategy not only provides a simple way to increase the resolution down to nanoscale but also extends the application of as‐prepared CsPbBr3 scintillator for high resolution X‐ray microscopic imaging.

In command of modern intelligent operations, in addition to solving the problem of multi-unit coordinated task assignment, it is also necessary to obtain a suitable plan according to the needs of decision makers. Based on these requirements, we established a multi-stage bi-objective weapon-target assignment model, and designed a new algorithm with niche and region self-adaptive aggregation (named MOEA/ D-NRSA) based on the decomposition-based multi-objective evolutionary algorithm (MOEA/D) to obtain richer solutions that meet the preferences of different decision makers. Compared with MOEA/D, MOEA/ D-NRSA has advantages in improving the convergence and maintaining the distribution of the solution. On the one hand, it contains a population evolution method based on niche technology to obtain better offspring; on the other hand, it has a new neighborhood selection and update strategy. This strategy first clusters the individuals in the objective space to divide into different regions, in which the subproblems can independently select the appropriate aggregation mode according to the clustering density of the region and update its neighborhood. This strategy can improve the uneven distribution of individuals and maintain the diversity and distribution of the population. Numerical experiments selected state-of-the-art algorithms for comparison, which proved the superiority of MOEA/D-NRSA.

High temperature superconducting (HTS) cable, with significant low dissipation and massive current carrying capability, is a promising solution for the shortage of transmission capacity in mega-cities. China Southern Grid launched a HTS cable project in 2017 to develop a medium voltage concentric HTS cable system for installation in the distribution grid at urban area in Shenzhen City. It is the first time that concentric HTS cable system is developed and will be the first HTS cable installed in urban grid in China. The cable core mainly consists of three concentric phases winded by YBCO tapes and cold dielectric insulations in between phase-to-phase, phase-to-former, and phase-to-screen. The cable has a rated voltage of 10 kV and a rated current of 2.5 kArms. The critical current ( $I_{c}$ ) is at least 6 kA per phase. The outline diameter of the cable core is 76 mm and the cryogenic pipe is 175 mm. As a middle step, we designed and manufactured a 30 m long prototype cable system and it was tested generally according to IEC 63075. For improvement of the manufacture processes, several short cable core samples were made, tested, and dismantled. The ultimate goal of the 30 m prototype is to verify the design and accumulate experience for the installation of the 400 m fully functional cable system in the grid. The test results of the 30 m cable prototype are presented and discussed. The 400 m class HTS concentric cable demonstration project has already started and it is expected to energize in grid in late September, 2021.

Abstract Background We aimed to explore the relationship between the neutrophil to lymphocyte ratio (NLR) and the early clinical outcomes in children with congenital heart disease (CHD) associated with pulmonary arterial hypertension (PAH) after cardiac surgery. Methods A retrospective observational study involving 190 children from January 2013 to August 2019 was conducted. Perioperative clinical and biochemical data were collected. Results We found that pre-operative NLR was significantly correlated with AST, STB, CR and UA (P

Betulinic acid (3β-Hydroxy-20(29)-lupaene-28-oic acid, BA) has excellent anti-cancer activity but poor solubility and low bioavailability. To improve the antitumor activity of BA, a polyvinyl caprolactam–polyvinyl acetate–polyethylene glycol (PVCL–PVA–PEG) graft copolymer (Soluplus) encapsulated BA micelle (Soluplus-BA) was fabricated. The Soluplus-BA micelles presented a mean size of 54.77 ± 1.26 nm and a polydispersity index (PDI) of 0.083. The MTT assay results showed that Soluplus-BA micelles increased the inhibitory effect of BA on MDA-MB-231 cells, mainly due to the enhanced accumulation of reactive oxygen species (ROS) and the destruction of mitochondrial membrane potential (MMP). Soluplus-BA micelles induced the DNA double-strand breaks (DSBs) as the γH2AX foci increased. Moreover, Soluplus-BA also inhibited the tube formation and migration of human umbilical vein endothelial cells (HUVECs), and inhibited the neovascularization of the chicken chorioallantoic membrane (CAM). This angiogenesis inhibitory effect may be accomplished by regulating the HIF-1/VEGF-FAK signaling pathway. The in vivo study confirmed the improved anti-tumor effect of Soluplus-BA and its inhibitory effect on angiogenesis, demonstrating the possibility of Soluplus-BA as an effective anti-breast cancer drug delivery system.

Under the threat of global climate change, China has proposed a dual carbon goal of peak carbon and carbon neutrality. As the vital carrier for territorial spatial planning, production–living–ecological (PLE) spaces drive carbon emissions and are important to the dual carbon goals. In this study, carbon emissions and sinks of PLE spaces in cities in Heilongjiang Province from 2005 to 2020 were calculated and spatial–temporal changes were analyzed. The carbon emission structure was analyzed in segmentation sectors. The land use changes and socioeconomic factors on carbon emissions were analyzed, and emission reduction strategies were implemented. The results show the following: (1) Carbon emissions from production and living spaces increased yearly. Carbon sinks were smaller than emissions, but capacity was stable. (2) Higher-emission cities were concentrated in southwest Heilongjiang, and carbon emission differences between regions gradually increased. (3) Among carbon emission sectors, agricultural and household made up smaller proportions, while animal husbandry, industrial, transportation, and traffic travel contributed most. Carbon emission structures were transformed by adjusting urban development and industrial structure. (4) For most cities, industrial space was the main emission space, but agricultural production and urban–rural living spaces dominated in some cities. (5) GDP, urbanization rate, and area of city paved roads suppressed emissions in cities with decreased carbon emission grades. The industrial structure and coal consumption inhibited emissions in cities with maintaining and increasing carbon emissions grades.

In order to improve the load-bearing performance of converter trunnion bearing, this paper proposes magnetic-hydraulic bearing which is a new coupled support technology that combines electromagnetic support and hydrostatic support. It can be realized the active control of electromagnetic and hydraulic pressure, and is conducive to extending the bearing replacement period. Based on the magnetic-hydraulic coupling, a mathematical model of the initial state of the radial support system is established, the calculation formula of bearing capacity of radial magnetic fluid bearing is deduced, and Matlab software is used to analyze the variation trend of bearing capacity and stiffness with rotor displacement. The optimization of structural parameters was carried out according to analysis of bearing characteristics, and it was concluded that the bearing performance was the best when the diameter of the bearing cavity was 10 mm, and the bearing capacity increased significantly when the thickness of the oil film was 70 μm. It provides a theoretical basis for the innovative design of converter trunnion support system.

This paper explores an ultrahigh dimming frequency Light-Emitting Diode (LED) pulse width modulation (PWM) shunt dimming driver that achieves the full-range dimming. Firstly, the dimming frequency is improved to 20kHz for avoiding flicker and audible noise in high dimming requirements application, such as film and television shooting. Secondly, this paper reduces dimming ratio loss at ultrahigh dimming frequency by removing output capacitor. As a result, given 1% dimming ratio is achieved. Subsequently, for improving LED current square waveform at ultrahigh dimming frequency, it is necessary to suppress parasitic oscillation at the falling edge in LED current. Therefore, this paper proposes a method which connects a fast recovery diode with LED in series. In such way, parasitic oscillation at the falling edge in LED current is suppressed. Meanwhile, linear dimming performance is improved such as dimming linearity of low ratio and circuit reliability. Finally, a 120 W experimental prototype is built to drive an LED array comprising 9 LEDs in parallel and 15 LEDs in series. The switching frequency and dimming frequency of prototype are 500 kHz and 20 kHz, respectively. In addition, it achieves full dimming range of 1% to 99.99%.

Magnetic liquid double suspension bearing (MLDSB) includes electromagnetic system and hydrostatic system, and the bearing capacity and stiffness can be greatly improved. It is very suitable for the occasions of medium speed, heavy load, and starting frequently. Due to the mutual coupling and interaction between electromagnetic system and hydrostatic system, the probability and degree of static bifurcation are greatly increased and the operation stability is reduced. And flow of bearing cavity, coil current, oil film thickness, and galvanized layer thickness are the key parameters to ensure operation safe and stable, which has an important influence on the static bifurcation behavior. So this article intends to establish the coupling model of MLDSB to reveal the range of parameter combination in the case of static bifurcation. The influences of different parameter groups on the singularity characteristics, phase trajectory, x−t curves, and suction basin of the single DOF bearing system are analyzed. The result shows that there are nonzero singularities and static bifurcation occurs when ε2>0 or δ2>0. As the flow of bearing cavity, coil current, oil film thickness, and galvanized layer thickness changes in turn, the singularities will convert between stable focus, unstable focus, stable node, and saddle point, and then the stable limit cycle may be generated. The attractiveness of singularity will change greatly with the flow of the bearing cavity and coil current changes slightly in the case of small current or large flow. The minimal change of galvanized layer thickness will lead to the fundamental change of the final stable equilibrium point of the rotor, while the final equilibrium point is slightly affected by the oil film thickness. This study can provide a reference for the supporting stability of MLDSB.

Porous metallic architectures with well-defined networks possess multiple reactivity center and large specific surface area, offer improved catalytic activity, adsorption capacity, and sensing abilities than bulk materials, thus be an increasingly popular materials in various fields. However, it is challenging to synthesis porous metallic structures in a green, facile and scalable way. Using bovine serum albumin (BSA) nanofibrous biofilms as sacrificial templates, a variety of porous metallic nanomeshes were readily formed through the adsorption of ions following by air calcination. The microstructures of the metallic nanomeshes are controllable, with pores ranging from 10−2 to 100 μm and particle diameter of 30–270 nm. Specifically, the Au nanomeshes displayed not only high plasmonic resonance properties as SERS substrates, but also multiple reactivity centers as electrochemical sensor for dopamineand H2O2.

Magnetic-liquid double-suspension bearing (MLDSB) is composed of an electromagnetic supporting system and a hydrostatic supporting system. Due to its greater supporting capacity and stiffness, it is appropriate for middle-speed applications, overloading, and frequent starting. However, because it contains two sets of systems, its structure and rotor support system are more complex. It contains strong nonlinear links. When the parameters of the system change, the bearing rotor may feature Hopf bifurcation, resulting in system flutter and reducing the operational stability of the magnetic fluid double-suspension bearing rotor, which has become one of the key problems restricting its development and application. As key parameters of MLDSB, the coil current and oil film thickness exert a major impact on Hopf bifurcation. Therefore, the mathematical model of MLDSB is established in this paper, and the border and direction of Hopf bifurcation, period, and amplitude of limit cycle are analyzed. The calculation, simulation, and experimental results show that when the coil current and oil film thickness of the bearing system are greater than the boundary value of the Hopf bifurcation, Hopf bifurcation will occur, resulting in the vibration of the bearing rotor and affecting the stability of the system. In addition, when analyzing the combined effects of coil current and oil film thickness on the Hopf bifurcation of the system, it was found that the boundary value of Hopf bifurcation in the system is reduced compared with when it is are affected solely due to the coupling of the two parameters. The period, amplitude and vibration speed of limit cycle increase with increases in the coil current and oil film thickness. Hopf bifurcation experiment was conducted on MLDSB testing system. The results show that Hopf bifurcation does not occur when i0 < 0.5 A, the bearing rotor operates stably in the balanced position, i0 > 1.0 A, Hopf bifurcation occurs in the system, and the bearing rotor vibrates with equal amplitude, which reduces the stability of operation. The research in this paper can provide a theoretical reference for the Hopf bifurcation analysis of MLDSB.

Magnetic-Liquid Double Suspension Bearing (MLDSB) is composed of an electromagnetic supporting and a hydrostatic supporting system. Due to greater supporting capacity and static stiffness, it is appropriate for occasions of middle speed, overloading, and frequent starting. Because of the complicated structure of the supporting system, the probability and degree of static bifurcation of MLDSB can be increased by the coupling of hydrostatic force and electromagnetism force, and then the supporting capacity and operation stability are reduced. As the key part of MLDSB, the controller makes an important impact on its supporting capacity, operation stability, and reliability. Firstly, the mathematical model of MLDSB is established in the paper. Secondly, the static bifurcation point of MLDSB is determined, and the influence of parameters of the controller on singular point characteristics is analyzed. Finally, the influence of parameters of the controller on phase trajectories and basin of attraction is analyzed. The result showed that the pitchfork bifurcation will occur as proportional feedback coefficient Kp increases, and the static bifurcation point is Kp = −60.55. When Kp < −60.55, the supporting system only has one stable node (0, 0). When Kp > −60.55, the supporting system has one unstable saddle (0, 0) and two stable non-null focuses or nodes. The shape of the basin of attraction changed greatly as Kp increases from −60.55 to 30, while the outline of the basin of attraction is basically fixed as Kp increases from 30 to 80. Differential feedback coefficient Kd has no effect on the static bifurcation of MLDSB. The rotor phase trajectory obtained from theoretical simulation and experimental tests are basically consistent, and the error is due to the leakage and damping effect of the hydrostatic system within the allowable range of the engineering. The research in the paper can provide theoretical reference for static bifurcation analysis of MLDSB.

Graphene, as a steady two dimensional (2D) carbon material, possesses intriguing physical and chemical properties, which arouses great interests of scientists for its applications in enormous fields. In particular, graphene and graphene oxide have been widely used for drug delivery and DNA detection based on π-π stacking and hydrophobic interactions. Besides, graphene with fluorescent molecules or nanoparticles and graphene quantum dots have also been frequently applied as fluorescent probe. In this article, advances of graphene and graphene oxide on biomedical applications will be highlighted from the perspective of biomolecular interaction, cell imaging, drug delivery, and toxicity.

The microspheres/nanosheets of the ZnSe were prepared by solvothermal route. The morphological, structural, optical, as well as photocatalytic properties of the ZnSe products were studied. SEM and TEM results showed that morphologies of the products were sensitive to the presence of water or not, and a mechanism was proposed. The products shows a weak blue emission band centered at 476 nm, which is attributed to the near-bandedge emission of the products, and the strong and broad peak at 520 nm is attributed to a defect-related emission. The PL and XRD results indicate that ZnSe microspheres have high crystalline and few defects compared with ZnSe nanosheets, the degradation for Rhodamine 6G shows that the photoactivity of ZnSe nanosheets is nearly twice that of ZnSe microspheres. Therefore, the decrease of defects implies the decrease of photocatalytic activity, and nanosheets is more suitable for the degradation of Rhodamine 6G.