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[Display omitted] Haloalkynes that could be accessed from diverse precursors, are versatile in synthetic chemistry as alkynylation and/or halogenation reagents, enabling concise and divergent delivery of functional molecules in selective manners. Recently, additional reactivity and substrate scope of haloalkynes, was also developed, facilitating expedient delivery of fused heterocycles. [ABSTRACT FROM AUTHOR]

The complexity of the environment makes rapidly-exploring random tree (RRT) difficult to handle dynamic obstacle avoidance and system constraint in real-time path planning for autonomous vehicles. To handle this issue, this paper proposes a novel real-time double-tree rapidly-exploring random tree (RDT-RRT) algorithm framework. The collision-free path by RRT after B-spline smooth treatment is adopted as the reference path to reduce invalid sampling. Integrating G1 Hermite interpolation with G2 Hermite interpolation reduces the sampling dimension and takes more efficient samples. The optimal distance metric is designed considering dynamic collision detection mechanism and utilized to estimate the costs of the samples in terms of path curvature. Moreover, to have a better understanding of the environment, convolutional neural network (CNN) is embedded to strengthen the collision detection mechanism. By RDT-RRT the smooth, collision-free paths with small curvature changes can be evaluated. For the evaluations of our proposal in global and local planning, the experiments for a real scaled autonomous vehicle are implemented through parallel computing. By comparing with the mainstream RRT-based algorithms, it has shown that in terms of the path quality, our method reduces 92 % and 88 % of cumulative curvature change respectively in obstacle-free and static obstacle scenarios. Compared with other RRT methods, RDT-RRT performs faster convergence rate and Parallel computing increases the updating frequency from 1.1 Hz to 5.5 Hz. The obstacle avoidance capabilities are also improved. [ABSTRACT FROM AUTHOR]

Toward the aim of zero tracking error and user-specified convergence rate, a data-driven output tracking design for unknown linear discrete-time systems is investigated in this work. For policy learning, we customize a virtual auxiliary system, based on which an enhanced Bellman equation with the user-specified convergence rate is derived. This allows us not to explicitly measure the time for the system evolution, while only the input–output data are sufficient in our design. By utilizing the robust output regulation technique, we can learn an optimal tracker for such an auxiliary system via policy iteration and value iteration. It is proved that the output tracking error of the original discrete-time system converges to zero at the specified convergence rate. The effectiveness of the proposed algorithms is illustrated by a simulation example. [ABSTRACT FROM AUTHOR]

Abstract Resilience of multi-agent systems (MAS) reflects their capability to maintain normal operation, at a prescribed level in the presence of unintended faults. In this paper, we investigate resilient control of MAS under faults on sensors and actuators. We propose four resilient state feedback based leader–follower tracking protocols. For the case of sensor faults, we develop an adaptive compensation protocol and an H ∞ control protocol. For the case of simultaneous sensor and actuator faults, we further propose an enhanced adaptive compensation protocol and an enhanced H ∞ control protocol. We show the duality between the adaptive compensation protocols and the H ∞ control protocols. For adaptive compensation protocols, faults on sensors and actuators are rejected by using local adaptive sensor and actuator compensators, respectively. Moreover, by employing a static output-feedback design technique, we propose H ∞ control protocols that guarantee bounded L 2 gains of certain errors in terms of the L 2 norms of fault signals. This further allows us to prove resilience even if sensor faults are unbounded. Finally, simulation studies validate the effectiveness of the proposed protocols. [ABSTRACT FROM AUTHOR]

Abstract Making a trade-off between the control accuracy and computational reduction is a problem frequently encountered in the system control design. This is especially difficult when one designs adaptive fuzzy (or neural network) controls for nonlinear systems, in which fuzzy controls have to consume many computational resources to tune a sufficiently large number of adaptive parameters, meanwhile nonlinear uncertainties block the high demanding control accuracy. Current works usually face a dilemma that, either the computation is reduced but the control accuracy is degraded due to the use of the norm estimation, or the asymptotic control is resulted but the computation is increased due to the extra compensation controls. To address such dilemma, we propose an asymptotic adaptive fuzzy tracking control algorithm, whose main feature is that only two adaptive laws are needed throughout the control scheme. In particular, we allocate one adaptive law to achieve adaptive fuzzy backstepping control for nonlinear systems with a focus on stabilizing the closed-loop system. We then allocate the other adaptive law not only to asymptotically drive the stabilization error to the zero, but also to achieve the elimination of overparametrization in a Nussbaum-like design, which is inspired by the tuning function-based approach. [ABSTRACT FROM AUTHOR]

This work presents an output-feedback policy learning algorithm underlining input–output system data for distributed robust optimal synchronization of heterogeneous multi-agent systems. The output-feedback synchronization problem in the context of this work is formulated via robust output regulation and reinforcement learning modeling the interactions among agents by a zero-sum game. The proposed learning and control structure only requires the local system data for each agent and distributed output data among communicating neighbors. We utilize system-level synchysis for the continuous-time state reconstruction for the distributed learning with convergence and stability proofs under the proposed output-feedback policy for solving the zero-sum game. We further show that policy learning is assured under the proposed data criteria relating to input–output data only rather than any inter-immediate gains from policy iterations. Based on the cooperative robust output regulation, this work gains robustness after the learning is complete and establishes an output data-driven distributed optimal robust synchronization without knowing accurate system dynamics. A numerical example shows the effectiveness of the proposed learning algorithm. [ABSTRACT FROM AUTHOR]

Three pyrazolium ionic liquids, 1,2-diethylpyrazolium bromide (DEPzBr), 1,2-diethyl-3-methylpyrazolium bromide (DEMPzBr), and 1,2-diethyl-3,5-dimethylpyrazolium bromide (DEDMPzBr), are firstly applied as catalysts for coupling reaction of carbon dioxide (CO 2 ) and propylene oxide (PO) with the propylene carbonate (PC) yields in a range of 82.7%–88.7% under a benign condition, 120 °C, 2.0 MPa initial CO 2 pressure and 4 h with 0.5 mol% catalysts loading. The relationship between structure and catalytic activity of pyrazolium ionic liquids are investigated by two different theoretical models, which indicates that both electrostatic interaction and hydrogen bond promote the ring-opening of PO. Both the theoretical and experimental results present that the catalytic activity decreases in the sequence of DEPzBr > DEDMPzBr > DEMPzBr. Pyrazolium ionic liquids would be employed as a novel efficient single-component catalyst without solvent and co-catalyst. It is expected that we would open an express pathway to develop new catalysts with the desired properties. [ABSTRACT FROM AUTHOR]

The efficient fixation of CO 2 without co-catalyst and solvent under metal-free condition is still an urgent topic in sustainable chemistry. In this work, a series of dialkylpyrazolium ionic liquids are employed to promote the cycloaddition of CO 2 and PO to produce PC. They would be easily synthesized by a simple one-pot reaction. The effect of alkyl chain length in cation and different anion is explored. Diethylpyrazolium iodide presents the excellent catalytic activity with the product yield of 96% and selectivity of 99% in a benign condition. Moreover, the catalyst could be reused for at least five times without significant loss of catalytic activity. An intensive structure-activity research testifies that the cycloaddition of CO 2 with PO is activated by a synergistic effect from both cation and anion of ILs. To confirm it, the detailed mechanism is investigated by density functional theory associated with the non-covalent interactions and atoms in molecule analysis. Besides the electrostatic interaction between cation of ionic liquid and PO, the noncovalent interaction, especially for hydrogen bond, plays a vital role in promoting the reaction. [ABSTRACT FROM AUTHOR]

The scarcity of high efficient red-emitting phosphorescent emitters, especially for deeply red emitter, has become the major road stone to block the further development of organic light-emitting diodes. Most of studies have been devoted to developing new Ir(III) complexes by variation of primary ligands. The ancillary ligand has attracted less attention. Four Ir(III) complexes, (DPQ) 2 Ir(pic) ( 1 ), (DPQ) 2 Ir(tmd) ( 2 ), (DPQ) 2 Ir(ozl) ( 3 ), and (DPQ) 2 Ir(iml) ( 4 ) with different ancillary ligands are explored from both emissive rule and quantum yields, where DPQ is 2,4-diphenylquinoline with a CF 3 group at meta position of the phenyl ring, pic is picolinate, tmd is 2,2,6,6-tetramethylheptane-3,5-diketonate, ozl is 2-(4,5-dihydrooxazol-2-yl)phenol, and iml is 2-(1-ethyl-4,5-dihydro-1 H -imidazol-2-yl)phenol. Radiative rate constant for phosphorescence ( k r ) is calculated by quadratic response time-dependent density functional theory (QR-TDDFT). The transition dipole moment, spin-orbit coupling matrix element, and singlet-triplet splitting energy related with the k r are also analyzed to further uncover the crucial factors to affect the k r . While the nonradiative rate constant for phosphorescence ( k nr ) is qualitatively estimated from both temperature-independent nonradiative rate constant ( k ′ nr ) and temperature-dependent nonradiative rate constant ( k nr (T)) viewpoints. The emissive wavelength of new designed Ir(III) complex 4 locates in the deeply red region. Moreover, it has the larger quantum yield because of both larger k r and smaller k nr . The variation of ancillary ligand is also an advisable choice to develop red-emitting Ir(III) complex with ideal quantum efficiency. [ABSTRACT FROM AUTHOR]

Multivariable adaptive control is an important and challenging research area, where it usually requires designing adaptive laws to estimate a number of unknown parameters. Hence, this process may excessively consume limitedly available computational resources and large amount of computational time, which may degrade system performances, particularly for the case of online updating of parameter estimates. Thus reducing the number of parameters to be estimated is a promising way to solve the problem. The state-of-the-art result in the area is to update just one adaptive parameter. However, the tracking errors are only ensured bounded and thus the resulting closed-loop system is not asymptotically stable. Hence, a question that arises is whether such a result of non-zero tracking errors is the price paid for reducing the number of updating parameters. Up to now, there is still no answer to this question. In this paper, we address such an issue and realize asymptotic stability with online estimation of just one parameter. To achieve such a goal, a novel dynamic loop gain function based approach is proposed to incorporate with the backstepping control design procedure, which enables us to solve the algebraic loop problem caused by all the existing traditional Nussbaum function based approaches and thus establish system stability. A bound for the tracking error is explicitly established in terms of L 2 norm, which helps improve the transient performance by selecting the control parameters. Moreover, guaranteed by the Barbalat’s Lemma, the tracking error is further ensured to approach zero asymptotically. Finally, simulation examples are conducted to testify the effectiveness of the proposed approach. [ABSTRACT FROM AUTHOR]

The mechanism of coupling reaction of CO 2 with propylene oxide (PO) catalyzed by the amino-functionalized imidazolium-based ionic liquid is theoretically investigated by the density functional theory (DFT). Although the mechanisms of the fixation of CO 2 catalyzed by various room-temperature ionic liquids or functionalized ionic liquids have been theoretically elucidated in previous literatures, it is not totally suitable for the amino-functionalized ionic liquid. First, the 1-(3-aminopropyl)-3-methylimidazolium chloride ([APmim]Cl) would react with CO 2 to produce the 1-(3-carbamic acid propyl)-3-methylimidazolium chloride ([CAPmim]Cl). Then, [APmim]Cl, [CAPmim]Cl, and combination of them would be employed as the catalyst leading to nine possible routes. Different from the previous work, this work allows a better comprehension of the mechanism by means of a new model that the cooperative effect of two same or different components is considered. Both the interaction between catalyst and reactant and the influence between different catalytic components are considered. Besides the nucleophilic attack of the Cl − anion, the [CAPmim] + cation is taken as the main component to activate the O atom of PO directly leading to the ring-opening. The [APmim] + cation is utilized to stabilize the [CAPmim] + , which is the most favorable route. The noncovalent interactions (NCI) plot is employed as a tool to analyze the reason of the higher catalytic efficiency of top three favorable routes. The hydrogen bond and dispersive attractive interaction is confirmed to play a determining role in the catalytic activity. [ABSTRACT FROM AUTHOR]

The mechanism of the reaction of CH 3 COCl with HNO has never been investigated by theoretical and experimental methods before, which is explored in this contribution. The geometries are optimized at the BMK/6-311+G(d,p) level. On the basis of the optimized geometries, the energy is further refined at the BMC-CCSD level. Finally, twenty-five pathways and corresponding possible products are located including the cleavage of N H, C C, C H, and C Cl bonds and formation of O H, O Cl, O N, O C, N Cl, N H, N C, H H, and H Cl bonds. However, most of reaction pathways are impossible because of the higher barrier heights and positive reaction energy. The most favorable pathway is the N H1 and C Cl bonds rupture and H1 Cl bond formation leading to products CH 3 CONO and HCl. [ABSTRACT FROM AUTHOR]

Reinforcement learning provides a powerful tool for designing a satisfactory controller through interactions with the environment. Although off-policy learning algorithms were recently designed for tracking problems, most of these results either are full-state feedback or have bounded control errors, which may not be flexible or desirable for engineering problems in the real world. To address these problems, we propose an output-feedback-based reinforcement learning approach that allows us to find the optimal control solution using input–output data and ensure the asymptotic tracking control of continuous-time systems. More specifically, we first propose a dynamical controller revised from the standard output regulation theory and use it to formulate an optimal output tracking problem. Then, a state observer is used to re-express the system state. Consequently, we address the rank issue of the parameterization matrix and analyze the state re-expression error that are crucial for transforming the off-policy learning into an output-feedback form. A comprehensive simulation study is given to demonstrate the effectiveness of the proposed approach. [ABSTRACT FROM AUTHOR]

Numerous binary catalysts of IL/Lewis acid have been developed for the coupling reaction of carbon dioxide and epoxides to form cyclic carbonates with high catalytic activity under benign environment. However, the mechanism is still obscure for most of catalysts. The catalytic mechanism of the binary catalysts hexaalkylguanidinium bromide/ZnBr 2 is elucidated by theoretical method in this work to obtain the reason of their high catalytic activity. Owing to the complicated of the binary catalysts, there are lots of possible attack forms. Finally, it is confirmed that the electrophilic attack from the Zn complex and the nucleophilic attack from the Br − anion are the essential factors to promote the ring opening of PO. Following the most favorable route, the catalytic activity of different binary catalysts, including the ILs/ZnBr 2 and NBu 4 Br/Zn(salphen), is compared. Moreover, the influence of the bulk of hexaalkylguanidinium salt on the catalytic activity is studied. The catalytic activity is enhanced with the increased bulk of the hexaalkylguanidinium salt. It is expected that our theoretical study would provide valuable clues to further refine the binary catalysts. [ABSTRACT FROM AUTHOR]

Recent results have emerged that policy iteration is a powerful reinforcement learning tool in designing a stabilizing control policy for continuous-time systems with unknown system dynamics. Policy iteration involves a model-based initialization stage, i.e., seeking an initial stabilizing control policy, which is, however, dependent on the full system dynamics including the drift dynamics and system input matrix. To remove such model requirements, this paper utilizes a homotopy-based initialization strategy for policy iteration, wherein a stabilizing control policy for continuous-time systems is obtained by gradually moving a stable system to the original system. We propose two homotopic policy iteration-based stabilizing control schemes, namely, a model-based design and a model-free design using system data, which are proved to place unstable poles into a stable region. The effectiveness of the proposed designs is validated through an illustrative example. [ABSTRACT FROM AUTHOR]

Abstract: In this study, both experiments and simulations are performed to investigate the thermal-fluid characteristics of a flat-fin heat sink with a pair of vortex generators installed in a cross flow channel. The effects of the distance between the trailing edges of the vortex generators, the distance between each vortex generator and the heat sink, the attack angle of the vortex generators, the height of the vortex generators, the configuration of the vortex generators, and the Reynolds number on the thermal-fluid performance of the plate-fin heat sink are elucidated. The performance of the heat sink with the vortex generators was compared to that without. The results thus obtained revealed that when the distance between the trailing edges of the vortex generators is too small, the thermal performance becomes worse because the air cannot easily flow into the heat sink. Regarding the effect of the position of the vortex generators on thermal performance, the best performance is achieve when the distance between the vortex generator trailing edges equals the length of the heat sink and the distance between the trailing edge of each vortex generator and the front end of the heat sink is zero. An attack angle of the vortex generators of 30° is preferred to optimize the thermal resistance and pressure difference. Although heat transfer increases with the height of the vortex generators, the pressure difference also increases. Regarding the effect of the configuration of the vortex generators on the performance of the heat sink, a common-flow-up configuration outperforms a common-flow-down configuration. The enhancement of the heat transfer of the heat sink by the use of vortex generators is greater, and the increase of the pressure difference is lower, at lower Reynolds numbers. [Copyright &y& Elsevier]

In this work, an event-triggered coordination problem for multi-agent systems with general linear dynamics is considered over directed communication graphs with a spanning tree. We study such a problem by using a Lyapunov equation for leaderless consensus. It is shown that a Lyapunov-based approach can complete stability analysis of event-triggered consensus of multi-agent systems over general directed graphs. [ABSTRACT FROM AUTHOR]

Summary: Objectives: The aim of this study was to develop a low shrinkage visible light curable nanocomposite dental restorative material without sacrificing the other properties of conventional materials. This nanocomposite was developed by using an epoxy resin 3,4-epoxycyclohexylmethyl-(3,4-epoxy)cyclohexane carboxylate (ERL4221) matrix with 55% wt of 70–100nm nanosilica fillers through ring-opening polymerization. GPS (γ-glycidoxypropyl trimethoxysilane) was used to modify the surfaces of silica nanoparticles. Results: The nanocomposite was shown to exhibit low polymerization shrinkage strain, which is only a quarter of currently used methacrylate-based composites. It also exhibited a low thermal expansion coefficient of 49.8μm/m°C which is comparable to that of the methacrylate based composites (51.2μm/m°C). The strong interfacial interactions between the resin and fillers at nanoscales were demonstrated by an observed high strength and high thermal stability of the nanocomposite. A microhardness of 62KHN and a tensile strength of 47MPa were reached. A high degree of conversion (∼70%) can be obtained after less than 60s of irradiation upon the nanocomposite. A transmission electron microscope (TEM) study of the nanocomposite showed no aggregation of fillers. Comparable results to the methacrylate based composites were obtained from the one day MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-2H-tetrazolium bromide) cytotoxicity test. Significance: The developed epoxy resin based nanocomposite demonstrated low shrinkage and high strength and is suitable for dental restorative material applications. [Copyright &y& Elsevier]

This study reports on a sediment toxicity test developed with a native amphipod strain of Ptilohyale barbicornis where sediments from 10 estuarine stations along the western coastline of Taiwan were evaluated with respect to trace metals and PAHs. The test was validated by determining dose–response relationships for aqueous copper, and cadmium and sodium dodecyl sulfate as well as copper-spiked sediment, showing a sensitivity of P. barbicornis indicating its capability serving as a toxicity test species. A significant negative correlation between growth effects after 28 days of exposure to field-collected contaminated sediments and PAHs concentrations was observed. Similarly, the chronic toxicity test showed that growth was mostly inhibited compared to controls, body lengths in particular being significantly different from controls (p < 0.05). Various estuarine sediment pollutants in the quality guidelines can be further evaluated using P. barbicornis to understand their comprehensive biological effects and ecological risks. • The sensitivity of the native amphipod P. barbicornis to estuarine sediments spiked with pollutants showed its suitability as a model species. • Growth measured as body length provided a more suitable endpoint than body weight in a chronic assay with P. barbicornis. • PAHs and metals of estuarine stations showed no correlation with the survival rate of P. barbicornis. [ABSTRACT FROM AUTHOR]

The resilience of multi-agent systems (MAS) measures the capability of recovering the cooperative performance after experiencing faults or uncertainties. In this paper, we seek the improvement of the synchronization resilience for MAS by means of addressing unknown faults on communication links. To this end, we first transform the resilient control problem into designing distributed state observers. In addition, we show that the proposed state observers are resilient to communication link faults. Finally, we provide the main result of this paper as a synchronization protocol for MAS even in the presence of communication link faults. [ABSTRACT FROM AUTHOR]

The electronic, optical, and hole transporting mobility of three organic hole transporting materials (HTMs), X59, X59-P, and X59-T, are investigated by combination of first principle and molecular dynamics associated with Marcus theory and Einstein equation. As compared with the experimental reported X59, the new designed X59-P has more stable HOMO energy level. Moreover, the latter has smaller reorganization energy and larger hole transfer integral resulting in the larger hole transporting mobility. Besides the hole transporting mobility, the solubility and stability of two designed molecules are also evaluated by comparison with X59, which are two important items to determine the cost and performance in real application of solar cell. More importantly, they would be synthesized in a benign condition without expensive materials. Our studies introduce a possible pathway to explore the efficient HTMs by suitable combination mode rather than development of new groups. [ABSTRACT FROM AUTHOR]

Abstract: To be a viable alternative, a biofuel should provide a net energy gain and be capable of being produced in large quantities without reducing food supplies. Amounts of agricultural waste are produced and require treatment, with rice straw contributing the greatest source of such potential bio-fuel in Taiwan. Through life-cycle accounting, several energy indicators and four potential gasification technologies (PGT) were evaluated. The input energy steps for the energy life cycle assessment (ELCA) include collection, generator, torrefaction, crushing, briquetting, transportation, energy production, condensation, air pollution control and distribution of biofuels to the point of end use. Every PGT has a positive energy benefit. The input of energy required for the transportation and pre-treatment are major steps in the ELCA. On-site briquetting of refused-derived fuel (RDF) provides an alternative means of reducing transportation energy requirements. Bio-energy sources, such as waste rice straw, provide an ideal material for the bio-fuel plant. [Copyright &y& Elsevier]

OBJECTIVE: To assess the efficacy and tolerability of weekly oral cyclophosphamide in combination with alternate-day prednisone (CP) as salvage therapy for patients with relapsed multiple myeloma (MM) after autologous stem cell transplantation (ASCT). PATIENTS AND METHODS: We retrospectively reviewed the medical records of all patients identified in our clinical database as having received CP as treatment for relapsed MM after ASCT at Princess Margaret Hospital between July 1998 and May 2004. The CP regimen consisted of oral cyclophosphamide at 500 mg once weekly and oral prednisone at 100 mg on alternate days. RESULTS: A total of 66 patients received the CP regimen, with a median of 2.0 prior therapies (range, 1.0-5.0) from time of diagnosis to initiation of CP. The median time from relapse after ASCT to start of CP therapy was 1.5 months (range, 0.0-23.5 months). Because of nonsecretory disease in 7 patients, only 59 patients were evaluable for response. The median duration of CP treatment was estimated at 5.8 months (95% confidence interval [CI], 4.6-7.8 months). With a median follow-up of 15.9 months (range, 1.4-67.2 months), 36 patients (61%) responded to treatment, 24 (41%) of whom had a partial response. The 1-year progression-free survival of all evaluable patients was estimated at 66% (95% CI, 54%-80%), with a median progression-free survival of 18.6 months (95% CI, 13.9-29.9 months). The median overall survival from time of initiation of CP was estimated at 28.6 months (95% CI, 22.1-not available months). CONCLUSION: Our data show that CP is an effective, well-tolerated, and convenient regimen as salvage therapy for MM after ASCT. [ABSTRACT FROM AUTHOR]

: PurposeTo identify the major soluble proteins from human vitreous, and to establish a baseline for comparison of vitreous samples from eyes with various diseases.: DesignLaboratory investigation.: MethodsNormal vitreous was obtained from eight human donor eyes and from eight eyes of patients undergoing diabetic vitrectomy. Vitreous specimens were subjected to SDS-PAGE and MALDI-TOF-MS analysis. Six specific antibodies were used to identify proteins using Western blot. Four proteins were localized within ocular tissue in a normal donor eyebank eye.: ResultsWe found eight distinct bands on SDS-PAGE in normal vitreous and two additional bands (hemoglobin) in eyes with diabetic retinopathy. Proteins were identified using MALDI-TOF-MS and confirmed by Western blot. We established a quantitative analysis of relative protein concentrations of undiluted vitreous. Immunohistochemistry localized selected proteins within the posterior segment layers.: ConclusionsWe present a normal human vitreous protein profile using current technologies and provide a baseline for comparison to ocular disease states. Tissue distribution of vitreous proteins may help to elucidate more specific protein function. [Copyright &y& Elsevier]

To investigate circular RNA (circRNA) expression profile via microarray, and further assess the potential of candidate circRNAs as biomarkers in Alzheimer's disease (AD). CircRNA expression profile in cerebrospinal fluid from 8 AD patients and 8 control (Ctrl) subjects was assessed by microarray. Subsequently, 10 candidate circRNAs from microarray were validated by reverse transcription quantitative polymerase chain reaction (RT-qPCR) in cerebrospinal fluid from 80 AD patients and 40 Ctrl subjects. By microarray, 112 circRNAs were upregulated and 51 circRNAs were downregulated in AD patients compared with Ctrl subjects, and these circRNAs were enriched in AD related pathways such as neurotrophin signaling pathway, natural killer cell mediated cytotoxicity and cholinergic synapse. By RT-qPCR, circ-LPAR1, circ-AXL and circ-GPHN were increased, whereas circ-PCCA, circ-HAUS4, circ-KIF18B and circ-TTC39C were decreased in AD patients compared with Ctrl subjects, and these circRNAs were disclosed to predict AD risk by receiver operating characteristics curve analysis. Further forward-stepwise multivariate logistic regression revealed that circ-AXL, circ-GPHN, circ-ITPR3, circ-PCCA and cic-TTC39C were independent predictive factors for AD risk. Besides, in AD patients, circ-AXL and circ-GPHN negatively correlated, while circ-PCCA and circ-HAUS4 positively correlated with mini–mental state examination score; Circ-AXL negatively correlated, while circ-PCCA, circ-HAUS4 and circ-KIF18B positively correlated with Aβ42 ; Circ-AXL and circ-GPHN positively correlated, whereas circ-HAUS4 negatively correlated with t-tau; Circ-AXL positively correlated with p-tau. Our study provides an overview of circRNA expression profile in AD, and identifies that circ-AXL, circ-GPHN and circ-PCCA hold clinical implications for guiding disease management in AD patients. [ABSTRACT FROM AUTHOR]