Search

We have designed and synthesized a π-stacked pure organic material (TPATA) with propeller-like A–(π-D)3 structure, which features intriguing photoluminescence properties and room temperature phosphorescence.

Sesquioxides such as Y2O3 and Sc2O3 are important optical materials, but the fabrication of their transparent ceramics remains a challenge due to the ultra-high melting point of over 2400 oC. In this work, a series of (Y1-xScx)2O3 transparent ceramics were successfully fabricated by a simple vacuum sintering process without any sintering additives, and the effect of Scandium (Sc) content on the crystal structure and optical/thermal/mechanical properties were evaluated. Y2O3 and Sc2O3 form a complete solid solution with a cubic bixbyite structure. The formation of (Y1-xScx)2O3 solid solution promotes the densification of ceramics, leading to the realization of high transparency close to the theoretical transmittance over a wide wavelength range of 0.35-8 mm. In particular, the in-line transmittance in the range of 0.6-6 mm remains above 80% for (Y1-xScx)2O3 with x = 0.23-0.31, while the pristine Y2O3 and Sc2O3 are opaque. Moreover, the mechanical properties including Vickers hardness (Hv), fracture toughness (KIC), and biaxial strength (δb) are evidently enhanced due to the solid solution strengthening, while the thermal conductivity is reduced due to the reduction of photon free path. This study demonstrates that forming of solid solution is a facile and universal approach for preparing sesquioxides transparent ceramics with high optical and mechanical quality.

(Ce,Gd):YAG-Al2O3 composite ceramics were prepared for high-brightness yellow LED (565−590 nm) applications. Phase fraction, microstructure, thermal quenching effect, and luminescent properties of composite ceramics with varying compositions were studied in detail. Collaborating composite ceramics with InGaN blue chips, the relationship between thermal conductivity, temperature rise during LED-driven phosphor conversion, and steady-state luminous efficiency were elucidated. As the proportion of Al2O3 increases from 0 to 40 wt%, the steady-state luminous efficiency of yellow LED is enhanced from 100.88–109.49 lm W−1, benefiting from the increased thermal stability and reduced operating temperature of ceramics (from 141.1–132.2 °C). Additionally, scattering behavior and extraction efficiency of composite ceramics with different thicknesses were investigated.

Using intra-fractional cone-beam CT (CBCT) to evaluate the amplitude changes and baseline shifts of respiratory motion in liver stereotactic body radiation therapy (SBRT).The amplitude changes and baseline shifts of respiratory motion for 24 liver patients were evaluated by the four-dimensional (4D) CT, inter- and intra-fractional CBCT. The difference of the average liver position errors among all treatment fractions and the 4D CT representthe baseline shifts. According to the baseline shifts, the ITV to PTV margin was recalculated and the plan was re-designed to compare the dosimetric variation.The systematic and random errors of the baseline shifts for intra-fractional CBCT in the left-right (LR), superior-inferior (SI), and anterior-posterior (AP) directions were 0.99/1.60 mm, 2.03/2.46 mm, and 1.02/2.07 mm, respectively. The new ITV to PTV margins should be 4.0 mm, 7.0 mm, and 4.0 mm, respectively. The amplitude change of motion between the 4D CT and the intra-fractional CBCT was 1.03 ± 4.35 mm, with 31% of fractions exceeding 5 mm. To achieve the same dose coverage of the new PTV, the DSignificant amplitude changes and baseline shifts of motion occurred during dose delivery compared with those in 4D CT. Using the ITV to PTV margin of 4.0 mm (LR), 7.0 mm (SI), and 4.0 mm (AP) can ensure the target dose coverage and keep the dose constrain of normal tissues at an acceptable level.

Roll-to-roll (R2R) printing systems provide a continuous process of thin, flexible material (called web) through printing cylinders, where the required patterns are printed on the web. Tension fluctuation caused by the upstream register control quantity may lead to the downstream register errors. Thus, it is a challenge to develop a register control algorithm to remove the couplings among the angular velocity, tension fluctuation, and register error. In this article, the register error is defined as the marks position misalignment between the first and the current printing unit. Based on the definition, a mathematical model of registration is derived. Based on the model, a fully decoupled proportional-derivative (FDPD) control algorithm is proposed to completely remove the coupling between the upstream register control quantity and the downstream register error. Simulations and experiments are carried out to demonstrate the effectiveness of the proposed control algorithm. Compared with the other compensation control methods, FDPD is a complete decoupling control method, which can control the register errors of all downstream printing units (more than seven printing units) within $\pm 0.05$ mm, even if the upstream printing unit has a 3 mm register error. Decoupling formula included in the FDPD control is a first-order compensation formula, which is easy to implement in the actual industry. Furthermore, the proposed FDPD can deal with the situation where two adjacent gravure cylinders have different web lengths, which is not taken into account by other control methods.

The roll-to-roll (R2R) web printing system is a complex coupling system, in which tension fluctuation is caused by upstream register control, thus results in downstream register errors. Therefore, it is indispensable to compensate for the couplings in order to improve the register precision in R2R printing systems. However, existing control methods do not realize complete decoupling due to their indirect calculation of compensations for the register errors. In this article, a mechanical model is set up to represent the direct relationship between the downstream register errors and all their upstream register controls. According to the model, compensation is calculated on the basis of the Lyapunov stability theorem to converge the register errors to zero. Then, a direct-decoupling closed-loop control method with first-order compensation terms, i.e., the direct-decoupling proportional derivative control (DDPD), is proposed to completely compensate for the couplings between all upstream register controls and downstream register errors. In addition, the first-order expression of the compensation makes it easy to implement in industrial applications. An industrial example indicates that the proposed control method eliminates the couplings and maintains the range of register errors within ±0.06 mm. Note to Practitioners —This article proposes a control strategy for the roll-to-roll (R2R) printing system, particularly for printing systems with electronic line shafts. Few existing studies have been done in detailedly analyzing the upstream register controls and the downstream register errors. This article establishes a mechanical model of printing registration and gives a systematic analysis of the complete relationship between upstream register controls and downstream register errors and then proposes a control strategy based on the Lyapunov stability analysis. The proposed method can be extended to other similar R2R systems. Simulation and industrial examples show that the control method is more feasible and effective compared with the existing methods. In future work, we will study a control method combined with the mechanical model and data model in different R2R systems.

Clinical laboratory in hospital can produce amounts of health data every day. The purpose of this study was to mine biomarkers from clinical laboratory big data associated with the air pollution health risk assessment using clinical records. 13, 045, 629 clinical records of all 27 routine laboratory tests in Changsha Central Hospital, including ALB, TBIL, ALT, DBIL, AST, TP, UREA, UA, CREA, GLU, CK, CKMB, LDL-C, TG, TC, HDL-C, CRP, WBC, Na, K, Ca, Cl, APTT, PT, FIB, TT, RBC and those daily air pollutants concentration monitoring data of Changsha, including PM

An appropriate register control method for a roll-to-roll (R2R) printing system must achieve not only high register accuracy but also the smoothness of the control signal and simple implementation. This paper compares recent register control approaches, i.e., model-based feed-forward proportional differential (MFPD), direct-decoupling proportional differential (DDPD) control, and fully decoupled proportional differential (FDPD) control, with three main performance indexes including register accuracy, implementation difficulty and smoothness of control signal. The mutual conversion between the different defined register errors in the three control methods is derived, so that the different defined register errors can be reciprocally transformed. According to the proposed mutual conversion analysis, the most appropriate conditions for using the three decoupling control methods are provided, which is very useful for the control method selection in industrial applications. Experiments and comparison are carried out to demonstrate the effectiveness of the proposed mutual conversion, which verify the derived most appropriate conditions of the three decoupling control methods.

Eu3+-activated oxide components appear as a kind of rare-earth red phosphors that can be used for warm white light-emitting diode (LEDs). At present, it is still a challenge to synthesize oxide-com...

Kawasaki disease (KD) is a multi-systemic vasculitis of unknown etiology that occurs mainly in children, and the disturbance of gut microbiota is generally believed to cause a hyperimmune reaction triggering KD. The aim of the study was to investigate the alterations in the fecal microbiota and assess its relationship with systemic inflammation. Totally 30 KD children were enrolled and followed up for 6 months, with another group of 30 age- and sex-matched healthy children as controls. Phylotype profiles of fecal microbial communities were analyzed using 16S rRNA gene sequencing. Serum inflammatory markers were detected by flow cytometer. We showed that KD children exhibited a significant reduction in fecal microbial diversity in the acute phase compared with the healthy controls. Enterococcus, Acinetobacter, Helicobacter, Lactococcus, Staphylococcus and Butyricimonas in acute KD children were significantly higher than the healthy children. Levels of systemic inflammation biomarkers, including IL-2, IL-4, IL-6, IL-10, TNF-α, and INF-γ, were significantly elevated in the acute KD children. Altered microbiota genera Enterococcus and Helicobacter abundances were shown to be correlated positively with IL-6, which were never previously reported in KD. This study suggested that gut microbiota alteration is closely associated with systemic inflammation, which provides a new perspective on the etiology and pathogenesis of KD.

To design a new breast vacuum bag to reduce global and local setup errors in post-mastectomy radiation therapy (PMRT). A total of 24 PMRT patients were immobilized with an old vacuum bag and 26 PMRT patients were immobilized with a new vacuum bag. The registration results were analysed using four regions of interest (ROI): the global ROI [including the whole region of the planning target volume (PTV), GROI], the supraclavicular area (SROI), the ipsilateral chest wall region (CROI) and the ipsilateral arm region (AROI). The global and local setup errors of the two groups were compared. The global setup errors of the new vacuum group were significantly smaller than those in the old vacuum group with the exception of yaw axes (P

Aim To assess the relationship between clinical parameters and medium term recovery time of coronary artery lesions (CALs). Methods In total, 344 Kawasaki disease patients were screened and 311 Kawasaki disease patients were included and followed-up for the next 2 years. Clinical records, clinical parameters and inflammatory biomarkers were collected for all subjects. Results Tumour necrosis factor (TNF)-α and myoglobin (MYO) levels in patients without recovery from CALs were significantly higher than those without CALs and with recovery from CALs. Kaplan-Meier survival analysis showed that in the high-TNF-α group, the estimated median time to recovery (5.0 months, 95% confidence interval (CI) 1.436-8.564) is significantly longer than the low-TNF-α group (2.00 months, 95% CI: 0.633-3.367, P = 0.044). Also, the estimated median time (5.0 months, 95% CI: 1.836-8.164) in the high-MYO group is significantly longer than the low-MYO group (2.00 months, 95% CI: 0.405-3.595, P = 0.002). Cox regression analysis showed independent factors for recovery of CALs included age, left coronary artery to aortic annulus ratio, TNF-α and MYO levels. Conclusions These findings suggest that clinical parameters such as age, left coronary artery to aortic annulus ratio, TNF-α and MYO levels associate with medium term recovery time of CALs and could help in the design of a clinical strategy for the surveillance and prevention of late cardiovascular events.

Ferroelectric single crystals with photoluminescence (PL) response are of great interest in the development of advanced multifunctional optoelectronic devices due to their special PL, ferroelectric...

Ferroelectric crystals with photoluminescence response are of great interest for the development of advanced multifunctional optoelectronic devices due to their photoluminescent, ferroelectric, pie...

Solid oxide fuel cell hybrid generation system is the best scheme for the load tracking of off-grid monitoring stations. But there are still potential problems that need to be addressed: preventing fuel starvation and ensuring thermal safety while meeting load tracking in hybrid power generation system. In order to solve these problems, a feasible hybrid power generation system structure scheme is proposed which combined SOFC subsystem and Li-ion battery subsystem. Then a model of the hybrid power generation system is built based on the proposed system structure. On this basis, an adaptive controller, include the adaptive energy management algorithm and current feedforward gas supply strategy, is applied to manage the power-sharing in this hybrid system as well as keep the system operating within the safety constraints. The constraints, including maintaining the bus voltage at the desired level, keeping SOFC operating temperature in safety, and mitigating fuel starvation are explicitly considered. The stability of the proposed energy management algorithm is analyzed. Finally, the developed control algorithm is applied to the hybrid power generation system model, the operation result proves the feasibility of the designed controller strategy for hybrid generation system and effectively prevent fuel starvation and ensure thermal safety.

The simultaneous realization of visible light response and high photocatalytic activity remains a challenging task for TiO2 despite extensive research. Herein, (Nb,Rh) codoping is adopted to extend the absorption band of anatase TiO2 into the visible-light region. Meanwhile, the dependence of the electronic structure, visible-light absorption, and photocatalytic performance on the dopant ratio as well as doping concentration is studied. Open shell t2g5 Rh(IV) and closed shell t2g6 Rh(III) coexist in Rh-doped TiO2, and the codoped Nb promotes a change in valence state from Rh(IV) to Rh(III). Rh(III) is the main active species in charge of the excellent photocatalytic performance, while Rh(IV) doping introduces electron/hole recombination centres. However, surprisingly, a trace of Rh(IV)-doping contributes to a decrease in electron transfer resistance and an increase in donor density, which help to improve photocatalytic performance. By virtue of the controlled content of Rh(III) and Rh(IV), Ti1−2xNbxRhxO2 exhibits a high hydrogen evolution rate of ∼9000 μmol g−1 h−1 in methanol solution, along with a remarkable photocurrent density of ∼9 μA cm−2 under visible-light irradiation, which are about 170 and 30 times higher than those of pristine TiO2 nanorods, respectively.

A 100 million ton crude oil purchases and sale contract signed between China and Russia, and the crude oil will pass through Kazakhstan and flow along the Alashankou-Dushanzi-Urumchi crude oil pipeline to western Region. As an important crude oil import channel, this paper analyzes the current situation of Alashankou-Dushanzi-Urumchi crude oil pipeline and puts forward some countermeasures. Both Russia and Kazakhstan are major crude oil exporters, with internal demand for exporting crude oil to China. There is a huge gap between domestic crude oil demand, and social and economic development depends on crude oil import. The geographical environment of the crude oil pipeline is conducive to pipeline protection. The security environment of Xinjiang has improved. The situation in Russia and Ukraine and the civil strife in Kazakhstan have limited impact on the pipeline which will have good development opportunities. Thus, this paper proposes the following management strategies. First of all, strengthen communication and coordination between upstream and downstream enterprises. Second, reduce cost and increase efficiency. Third, attach importance of the application of new technologies. Fourth, establish emergency plans and hold emergency drills for emergencies such as COVID-19 outbreak and pipeline leakage. Fifth, strengthen anti-terrorism and riot control. Sixth, strengthen corporate culture and talent team construction.

Fundamental understanding of the effect of doping on the optical properties of 3D double perovskites (DPs) especially the dynamics of self-trapped excitons (STEs) is of vital importance for their optoelectronic applications. Herein, a unique strategy via Cu

Background: Prostate alignment is subject to interobserver variability in cone-beam CT (CBCT)-based soft-tissue matching. This study aims to analyze the impact of interobserver variability in CBCT-based soft-tissue matching for prostate cancer radiotherapy.Methods: Retrospective data, consisting of 156 CBCT images from twelve patients with intermediate- or high-risk prostate cancer were analyzed in this study. To simulate interobserver variability, couch shifts of 2 mm relative to the resulting patient position of prostate alignment were assumed as potential patient positions (27 possibilities). For each CBCT, the doses of the potential patient positions were recalculated using deformable image registration-based synthetic CT. The impact of the simulated interobserver variability was evaluated using tumor control probabilities (TCPs) and normal tissue complication probabilities (NTCPs).Results: No significant differences in TCPs were found between prostate alignment and potential patient positions (0.944 ± 0.003 vs 0.945 ± 0.003, P = 0.117). The average NTCPs of the rectum ranged from 5.16 (%) to 7.29 (%) among the potential patient positions and were highly influenced by the couch shift in anterior-posterior direction. In contrast, the average NTCPs of the bladder ranged from 0.75 (%) to 1.12 (%) among the potential patient positions and were relatively negligible.Conclusions: The NTCPs of the rectum, rather than the TCPs of the target, were highly influenced by the interobserver variability in CBCT-based soft-tissue matching. This study provides a theoretical explanation for daily CBCT-based image guidance and the prostate-rectum interface matching procedure.Trial registration: Not applicable.

The level of CHB virus (HBV) core antibody (HBcAb) is different in four stages of chronic HBV infection and may be used for differential diagnosis of the natural history of chronic HBV infection. To address this question, we examined multiple blood biomarkers and assessed the efficacy to diagnose different stages of chronic HBV infection. The quantitative detection of HBcAb, hepatitis B surface antigen (HBsAg), HBV DNA, alanine aminotransferase (ALT), aspartate aminotransferase (AST), and platelet count (PLT) were determined in the serum of 73 cases of low-replicative phase (LR), 46 cases of immune-tolerant phase (IT), 44 cases of immune clearance phase (IC), and 57 cases of HBeAg-negative hepatitis (ENH). Differentiating performance of these serum protein levels was analyzed by receiver operating characteristic (ROC) curve analysis. Our results showed that the levels of HBcAb, ALT, and AST levels were significantly higher in IC and ENH than those in LR and IT (both P ≤ 0.001 ). The levels of HBV DNA and HBsAg were higher in IC and IT than those in LR and ENH (both P ≤ 0.001 ). Logistic regression models showed that HBcAb, HBsAg, HBV DNA, ALT, and AST were the independent variables, respectively, and when combined, they provided high diagnostic accuracy for the staging of CHB. To sum up, HBcAb quantification is a new index, which can reflect whether the liver is in the immune activation state of HBV infection, and is related to the inflammatory state of the host liver. The combined detection of HBcAb quantification and other indicators has showed promising efficiency for staging of IC and ENH and can assist the diagnosis and treatment of CHB.