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•Mn doped Co3O4 (MnxCoyO) deposited on NF presents mesoporous nanoneedle structure.•Mn1.5Co0.75O/NF shows remarkable capacitance retention of 104% after 10,000 cycles.•The assembled ...ASC shows high energy density of 10.63 Wh kg−1 (at 14.7 kW kg−1).
Long–term cycling stability is an important criterion and big challenge for pseudocapacitive materials. Ultra-stable manganese doped Co3O4 mesoporous nanoneedles were synthesized via one-step hydrothermal reaction followed by annealing grown on nickel foam (noted as MnxCoyO/NF, x + y = 2.25) for supercapacitors. The Mn doping in Co3O4 was confirmed by several techniques. Among various MnxCoyO/NF electrodes, the Mn1.5Co0.75O/NF demonstrated the superior electrochemical performance, with an excellent cycling stability of 104% capacitance retention after 10 000 charge–discharge cycles at 6 A g−1, as well as a good capability (668.4 F g−1 at 1 A g−1 compared to that of undoped Co3O4 which is 201.3 F g−1). Moreover, the assembled asymmetric supercapacitor based on Mn1.5Co0.75O/NF//graphene performs a high energy density of 25.88 Wh kg−1 (at 359.5 W kg−1) and a high power density of 14.7 kW kg−1(at 10.63 Wh kg−1). The improved electrochemical properties are mainly owing to the enhanced intrinsic conductivity and electrochemical activity of Co3O4 after doped with appropriate Mn concentration. The three-dimensional nanostructure of mesoporous nanoneedle array grown on NF also provides short ion diffusion path and large active surface areas, contributing to the high rate performance and high energy density. This study may offer a new approach to fabricate the unique 3D nanostructured electrode materials based on doped metal oxides for supercapacitors with long-term cycling stability and high energy density.
The human colorectal carcinoma cell line LS513 exhibits epithelial morphology, adherent properties and can grow subcutaneously to form tumors in nude mice. Thus, it is a potential model for mouse ...xenograft efficacy studies. The present study characterized the expression and activity of P-gp, BCRP and MRP2 in LS513 cells.
We investigated the expression of these ATP-binding cassette transporters by Western blot and their activity was also examined using cell culture inserts, where the LS513 cells were grown to confluence for 9 days. The transport of model substrates of P-gp (amprenavir, ritonavir and topotecan), BCRP (topotecan) and MRP2 (SN-38) was studied in the apical to basolateral (A–B) and basolateral to apical (B–A) directions. P-gp, BCRP and MRP2 could be detected by western blot. The LS513 cells exhibited markedly higher transport in the B–A direction than in the A–B direction for the probe substrates tested, with efflux ratios (ERs; B–A/A–B) of 10, 21, 40 and 50 for amprenavir, ritonavir, topotecan and SN38, respectively. The ER could be significantly reduced with the addition of inhibitors of P-gp (GF120918), BCRP (FTC), and MRP2 (MK571), confirming the activity of these transporters in the LS513 cells.
•Two semi-active hybrid battery systems combining LFP and LTO batteries are proposed.•A unified fuzzy-logic energy management strategy is designed to mitigate LFP degradation.•Hybrid battery systems ...were tested in simulated daily electric taxi operation.•One system increased battery life more, with 45.4% lifespan improvement.•The other achieved 12.49% annual average cost and 39.41% distance-based cost reduction.
This paper proposes two semi-active configurations for hybrid battery system (HBS) in which LiFePO4 (LFP) and Li4Ti5O12 (LTO) batteries are combined to prolong the life span of LFP batteries used in electric vehicles (EVs). To protect the LFP batteries from frequent peak power demands, the first configuration (HBS #1) uses diodes and switches, while the second (HBS #2) adopts a bidirectional DC/DC convertor to decouple various batteries. To make a fair comparison of the two configurations, their component sizes are firstly determined using brute-force search considering energy capacity and cost. Then, a unified fuzzy-logic energy management strategy was designed and optimized for each configuration to mitigate LFP battery degradation. Simulated implementation of HBSs #1 and 2 in an electric taxi with standard daily operation (driving nearly 400 km per day) and charging patterns revealed that both have longer LFP lifespans (44.4% and 45.4% improvement, respectively), lower annual costs (12.49% and 11.52% reduction, respectively) and reduced distance-based costs (39.41% and 39.18% reduction, respectively) than a single-LFP battery configuration. Although HBS #2 demonstrated more battery life improvement, HBS #1 was found to be cheaper in EV application from the perspectives of total and distance-based cost.
The bionic polarization sensor (PS)/MEMS inertial measurement unit (MIMU) integrated system can provide reliable attitude and heading information for unmanned vehicles in the case of GNSS rejection. ...However, the existing measurement methods have poor adaptability to inclining, sheltering, and other harsh environments, and do not make full use of the complementary characteristics of the gyroscopes, accelerometers, and PS, which seriously affects the system performance. Therefore, this paper proposes an attitude and heading measurement method based on an adaptive complementary Kalman filter (ACKF), which corrects the gyroscopes according to the gravity measured by the accelerometers to improve the attitude accuracy and fuses the IMU heading and tilt-compensated polarization heading by Kalman optimal estimation. On this basis, the maximum correlation entropy of the measured gravity and the theoretical gravity is used to construct an adaptive factor to realize the adaptive complementary of the gyroscopes and the accelerometers. Finally, the effectiveness of the method is verified by the outdoor rotation test without occlusion and the vehicle test with occlusion. Compared with the traditional Kalman filter, the pitch, roll, and heading RMSE of the vehicle test are reduced by 89.3%, 93.2% and, 9.6% respectively, which verifies the great advantages.
Ligand-induced chirality in semiconducting nanocrystals has been the subject of extensive study in the past few years and shows potential applications in optics and biology. Yet, the origin of the ...chiroptical effect in semiconductor nanoparticles is still not fully understood. Here, we examine the effect of the interaction with amino acids on both the fluorescence and the optical activity of chiral semiconductor quantum dots (QDs). A significant fluorescence enhancement is observed for l/d-Cys-CdTe QDs upon interaction with all the tested amino acids, indicating suppression of nonradiative pathways as well as the passivation of surface trap sites brought via the interaction of the amino group with the CdTe QDs’ surface. Heterochiral amino acids are shown to weaken the circular dichroism (CD) signal, which may be attributed to a different binding configuration of cysteine molecules on the QDs’ surface. Furthermore, a red shift of both CD and fluorescence signals in l/d-Cys-CdTe QDs is only observed upon adding cysteine, while other tested amino acids do not exhibit such an effect. We speculate that the thiol group induces orbital hybridization of the highest occupied molecular orbital (HOMOs) of cysteine and the valence band of CdTe QDs, leading to the decrease of the energy band gap and a concomitant red shift of CD and fluorescence spectra. This is further verified by density functional theory calculations. Both the experimental and theoretical findings indicate that the addition of ligands that do not “directly” interact with the valence band (VB) of the QD (noncysteine moieties) changes the QD photophysical properties, as it probably modifies the way cysteine is bound to the surface. Hence, we conclude that it is not only the chemistry of the amino acid ligand that affects both CD and PL but also the exact geometry of binding that modifies these properties. Understanding the relationship between the QD’s surface and chiral amino acid thus provides an additional perspective on the fundamental origin of induced chiroptical effects in semiconductor nanoparticles, potentially enabling us to optimize the design of chiral semiconductor QDs for chiroptic applications.
To assess the contemporary prevalence and decade-long trends of sleep duration, sleep disorders and trouble sleeping among adults in the United States, as well as their risk factors, from 2005 to ...2018.
We used National Health and Nutrition Examination Survey data to calculate the sleep duration and weighted prevalence of sleep disorders and trouble sleeping in adults aged 20 years or older. Sleep duration, sleep disorders and trouble sleeping were assessed by questionnaire.
A total of 27,399 people were included in the survey on sleep duration, with a weighted percentage of normal sleep (7–8 h/night) of 56.33 % (95 % CI, 53.06–59.60 %) and a weighted percentage of short sleep (5–6 h/night) of 31.73 %. In stratified descriptions, participants aged 40–49 years were more likely to sleep less than five hours, while women aged 80 years and older were more likely to sleep longer and blacks were more likely to sleep shorter. A total of 27,406 participants were included in the survey for sleep disorders. The weighted proportion of the population with sleep disorders was 8.44 % (95 % CI, 7.79–9.8 %). Independent risk factors for sleep disorders were being 40–69 years old, being white, having a high education level, smoking, having hypertension, diabetes, heart disease, and BMI ≥ 25. From 2005 to 2014, the prevalence of sleep disorders increased year by year, from 7.44 % in 2005–2006 to 10.40 % in 2013–2014 (P for Trend<0.001). A total of 38,165 participants were included in the survey on trouble sleeping. The weighted proportion of the population with troubled sleeping was 27.30 % (25.70–28.90 %). Independent risk factors for troubled sleeping were being 30–79 years old, being white, having a high education level, smoking, drinking, having hypertension, diabetes, heart disease and BMI ≥ 25. From 2005 to 2018, the prevalence of trouble sleeping increased annually, from 24.44 % in 2005–2006 to 30.58 % in 2017–2018 (P for trend<0.001).
Adults in the United States are likely to have abnormal sleep durations, and the prevalence of sleep disorders and troubled sleeping is on the rise.
•We used the world's largest public database (NHANES) to conduct the largest sample size study to date.•A total of 27399 people were included in the survey on sleep duration, with a weighted percentage of normal sleep of 56.33% and a weighted percentage of short sleep of 31.73%.•Adults in the United States are likely to have abnormal sleep durations, and the prevalence of sleep disorders and troubled sleeping is on the rise.
Se source cracking is reported with positive influence on CIGS absorber and device. We apply thermal cracking selenium source to co-evaporation processes, and investigate the influence of cracking Se ...source temperature on the CIGS absorber and device performance. The absorber films are investigated by XRF, SEM, XRD (GIXRD), SIMS, CV and Current-Voltage characterization. As the cracking temperature increase, the film topography tend to exhibit copper poor morphology, namely layered structure. The film preferred orientation was not significantly influenced by cracking temperature. For the device fabricated, we find that high thermal crack temperature decreases the open circuit voltage and fill factor. Further analysis of the IV data, we conclude that major recombination occurs in the space charge region. Though no iron material is applied in thermal cracking unit, the Fe intensity of high cracking temperature sample is still higher than those of low cracking temperature ones. Also, the cracking Se source facilitate the diffusion of Ga and In, which is similar to elevating substrate temperature. CV measurement unveiled that deep level defect concentration is higher in high cracking temperature samples. Further investigation and experiment including IVT, AS measurement and removal of material containing iron in Se source is carrying out to determine whether these defects are introduced only by impurities or by selenium activity induced atomic vacancy or substitution defects.
SU5416, a selective inhibitor of the tyrosine kinase activity of the vascular endothelial growth factor (VEGF) receptor Flk-1/KDR, is currently in Phase III clinical trials for the treatment of ...advanced malignancies. In cellular assays, SU5416 inhibits the VEGF-dependent mitogenic/proliferative response of human umbilical vein endothelial cells (HUVECs). In tumor xenograft models, SU5416 inhibits the growth of tumors from a variety of origins by inhibiting tumor angiogenesis. In three different human tumor xenograft models, infrequent (once or twice a week) administration of SU5416 is efficacious despite the fact that it has a short plasma half-life (30 min), which suggests that SU5416 has long-lasting inhibitory activity in vivo. The goal of the present study was to determine the basis for the prolonged activity of SU5416. The results indicate that a short (3 h) exposure to 5 microM SU5416 (to mimic plasma levels of the compound as measured in patients who were receiving SU5416 therapy) produced long-lasting (at least 72 h) inhibition of the VEGF-dependent proliferation of HUVECs in culture, which indicate that SU5416 has long-lasting inhibitory activity in vitro as well as in vivo. SU5416 treatment of HUVECs did not affect surface expression of Flk-1/KDR or the affinity of the receptor for VEGF. Instead, the durability of the in vitro activity of SU5416 was shown to be attributable to its long-lasting ability to specifically inhibit VEGF-dependent phosphorylation of Flk-1/KDR and subsequent downstream signaling, although SU5416 is not an irreversible inhibitor of Flk-1/KDR tyrosine kinase activity. The long-lasting inhibition of cellular responses to VEGF was attributable to the accumulation of SU5416 in cells, as shown using radiolabeled compound, such that inhibitory cellular concentrations of SU5416 are maintained long after the removal of the compound from the medium. The long-lasting inhibitory activity of SU5416 in vitro is consistent with the finding that SU5416 has demonstrated evidence of biological activity in clinical studies when administered twice a week despite a short plasma half-life.
•The fusion of two constraints are proposed to improve the accuracy of spatial positions of projection points.•Double constrained intersurface mutual projection is further carried out between the ...single frame and the cluster centers.•An evaluation method for separating registration error from instrument error is proposed.
The accuracy of 3D shape measurement directly determines the quality and reliability of intelligent manufacturing, and point cloud registration is the key factor. However, the dislocation of discrete point clouds in the overlapping area seriously reduces the registration accuracy. This paper proposes a new high-accuracy registration method based on double constrained intersurface mutual projections. First, the initial registration set is built by mutual projections between similar local regions, then the final registration set is determined by the rigid transformation consistency constraint, finally, high-accuracy pairwise registration is realized. On this basis, the K-means clustering is further fused to achieve multiview global optimization. On Stanford dataset, both of the pairwise and multiview registration error significantly decreased. In the experiment with GoScanG1 scanner, the surface error of pairwise registration was reduced by 2.2%; that of the multiview registration was reduced by 42.5%, which shows the advancement of the new method in actual measurements.
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