Traffic flow is used as an essential indicator to measure the performance of the road network and a pivotal basis for road classification. However, the combined prediction model of traffic flow based ...on seasonal characteristics has been given little attention at present. Because the seasonal autoregressive integrated moving average model (SARIMA) has superior linear fitting characteristics, it is often used to process seasonal time series. In contrast, the non-autoregressive dynamic neural network (NAR) has a vital memory function and nonlinear interpretation capabilities. They are suitable for constructing combined forecasting models. The traffic flow time series of a highway in southwest China is taken as the research object in this paper. Combining the SARIMA (0,1,2) (0,1,2)12 model and the NAR model with 15 hidden layer neurons and fourth-order delay, two combined models are constructed: the linear and nonlinear component combination method is realized by the SARIMA-NAR combination model 1, and the MSE weight combination method is used by the SARIMA-NAR combination model 2. We calculated that the prediction accuracy of SARIMA-NAR combined model 1 is as high as 0.92, and the prediction accuracy of SARIMA-NAR combined model 2 is 0.90. In addition, the traffic flow forecast under the influence of the epidemic is also discussed. Through a comprehensive comparison of multiple indicators, the results show that the SARIMA-NAR combined model 1 has better road traffic flow fitting and prediction effects and is suitable for the greater volatility of traffic flow during the epidemic. This model improves the effectiveness and reliability of traffic flow forecasting, and the forecasting process is more convenient and efficient.
Carbon-based functional materials, such as grapheme and MXenes, have been widely explored as Terahertz (THz) absorbers due to their broad structural-dependent properties, however, they usually suffer ...from high-cost, complex fabrication process and narrowband characteristics. Here, a broadband, low-cost and flexible THz absorber is realized based on annealed carbonized sponge (CS) that is obtained from a commercially available melamine sponge through a pyrolysis process conducted in an inert atmosphere. Due to the ultra-high porosity and good conductivity, the obtained CS shows excellent shielding and absorption performance with the maximum electromagnetic interference shielding effectiveness value of 49 dB and maximum reflection loss value of 47 dB, respectively, covering 100% qualified frequency bandwidth ranging from 0.25 to 3.5 THz, which far extends most reported materials. Furthermore, this obtained efficient THz absorber is demonstrated by THz transmission and reflection imagings, which demonstrate its potential applications in electromagnetic stealth, shielding, and beyond.
Laser shock forming (LSF) is an emerging method for metal sheet forming, and it can also be used to adjust the curvature of the curved metal. A series of laser shock adjustment experiments were ...conducted on 1-mm-thick curved aluminum 6061-T6 sheets using pulsed Nd
3+
:YAG laser operating at 1064-nm wavelength. The effects of various factors on the curvature adjustment were studied, including laser energy, impacted area, coverage rate of laser spots, and initial sheet shape. The mechanisms of curvature adjustment by LSF were studied by FEM simulation. The results have shown that the stress gradient mechanism and the shock bending mechanism were responsible for the two different kinds of deformation. The characteristic difference between the two mechanisms lies in whether the plastic deformation is directly induced on the bottom surface when the laser-induced shock wave is transmitted to the bottom surface. The curvature of the metal sheet can be adjusted conveniently within a certain range by changing the laser processing parameters, which is very useful for the engineering application.
In this study, a post-treatment method combining annealing and laser shock peening (LSP) is used to tailor the microstructure and mechanical properties of CrMnFeCoNi high-entropy alloy (HEA) prepared ...by laser directed energy deposition (LDED). The microstructure, microhardness, residual stress and tensile property of the as-built, annealed, LSP and annealed + LSP specimens are compared. Results indicate that LSP produces greater plastic deformation on the surface of annealed specimen compared to the pristine as-built specimen, as manifested by a thicker plastically-affected layer. Recrystallization, dislocation network annihilation and thermal stress relaxation caused by annealing contribute to an increase in the plasticity of LDED-prepared specimens, which provides great strengthening conditions for LSP. Gradient strain hardening and compressive residual stress are gained in the surface layer of the annealed specimen subjected to LSP. Moreover, plastic deformation induces a gradient microstructure consisting of ultra-fine grains, high-density mechanical twins and slip bands in order. An excellent strength–ductility synergy is achieved in LDED-prepared CrMnFeCoNi HEA after combined post-treatment of annealing and subsequent LSP.
•Combined post-treatment of annealing and LSP is employed to modify LDED-prepared CrMnFeCoNi HEA.•The microstructural evolution of LDED-prepared CrMnFeCoNi HEA subjected to annealing and LSP in turn is summarized.•An excellent strength–ductility synergy is achieved in LDED-prepared CrMnFeCoNi HEA after combined post-treatment.
•A strategy to specifically identify substances through correlating the substance fingerprint peak with the resonant frequency shift of the metamaterial sensors has been presented and demonstrated ...experimentally.•Three metamaterial sensors with different resonance frequencies were fabricated by ultrafast laser direct writing, and they all have good sensing performance.•The experimental results show that all three structures can accurately identify the three pesticides.
In this work, a strategy to specifically identify substances through correlating the substance fingerprint peak with the resonant frequency shift of the metamaterial sensors has been presented and demonstrated experimentally. Three metamaterial sensors with different resonance frequencies were fabricated by ultrafast laser direct writing, and they all have good sensing performance. Due to the different matching degrees between the sensor resonance peak and the substance fingerprint peak, different frequency shifts of the sensor resonance peak were obtained. The better the fingerprint peak matches the sensor resonance peak, the greater the shift of the sensor resonance peak. On the contrary, the smaller shift will be obtained. Through this method, the correlation between the resonant frequency shift of the sensor and the fingerprint peak of the substance is developed. Thus, within a certain range of some unknown substances, the fingerprint peak positions of the substances can be deduced through the frequency shifts of the sensor. This phenomenon was used for the specific identification of the substances. This study provides a new idea for the specific detection of the substances by the metamaterial sensor.
Laser peen forming (LPF) is suitable for shaping sheet metals without the requirement for die/mold and without causing high temperatures. An analytical model for estimating the bending curvatures of ...LPF is convenient and necessary for better understanding of the physical processes involved. In this paper, we describe a new analytical model based on internal force balance and the energy transformation in LPF. Experiments on 2024 aluminum alloy sheets of 1-3 mm thickness were performed to validate the analytical model. The results showed that for 1 mm and 3 mm thick-thin plates, the curvature obtained by the analytical model changes from -14 × 10
mm
and -1 × 10
mm
to 55 × 10
mm
and -21 × 10
mm
, respectively, with the increase of laser energy, which is consistent with the experimental trend. So, when either the stress gradient mechanism (SGM) or the shock bending mechanism (SBM) overwhelmingly dominated the forming process, the analytical model could give relatively accurate predicted curvatures compared with the experimental data. Under those conditions where SGM and SBM were comparable, the accuracy of the model was low, because of the complex stress distributions within the material, and the complex energy coupling process under these conditions.
Background
Exhaustion of CD8
+
tumor-infiltrating lymphocytes (TILs), characterized by the overexpression of immune checkpoints (IC), is a major impediment to anti-tumor immunity. However, the ...exhaustion status of CD8
+
TILs in angioimmunoblastic T cell lymphoma (AITL) remains unclear. Therefore, we aimed to elucidate the exhaustion status of CD8
+
TILs in AITL and its influence on prognosis.
Methods
The correlation between CD8
+
TILs and IC expression in AITL was analyzed using single-cell RNA sequencing (n = 2), flow cytometry (n = 20), and RNA sequencing (n = 20). Biological changes related to CD8
+
TILs exhaustion at different cytotoxic T lymphocyte (CTL) levels (mean expression levels of CD8A, CD8B, GZMA, GZMB, and PRF1) in AITL were evaluated using RNA sequencing (n = 20) and further validated using the GEO dataset (n = 51). The impact of CD8 protein expression and CTL levels on patient prognosis was analyzed using flow cytometry and RNA sequencing, respectively.
Results
Our findings demonstrated that the higher the infiltration of CD8
+
TILs, the higher was the proportion of exhausted CD8
+
TILs characterized by the overexpression of multiple IC. This was accompanied by extensive exhaustion-related biological changes, which suggested severe exhaustion in CD8
+
TILs and may be one of the main reasons for the poor prognosis of patients with high CD8
+
TILs and CTL.
Conclusion
Our study comprehensively reveals the exhaustion status of CD8
+
TILs and their potential negative impact on AITL prognosis, which facilitates further mechanistic studies and is valuable for guiding immunotherapy strategies.
Understanding the selectivity mechanism of inhibitors towards homology proteins helps to design selective candidates. Phosphodiesterase (PDE) family members act in the degradation of cAMP and cGMP, ...among which some isoforms such as PDE9A are attracting interest for Alzheimer’s disease treatment, while PDE10A is used as target for treating schizophrenia. In this study, computational methods were used to investigate the major features of PDE9A/10A, with the purpose to provide deep understanding of the molecular mechanism of selective inhibition towards these two isoforms. Our result revealed that two conserved residues Gln453 and Phe456 were proven to be crucial for the binding affinity and inhibitory selectivity of PDE9A inhibitors. In addition, the high-affinity PDE9A inhibitors always interact with the conservative hydrophobic pocket as well as Tyr424 and Ala452 of PDE9A, while PDE10A selective inhibitors need to have two hydrophobic groups and two hydrogen bond donors to interact with the conservative Tyr693, Gln726, and Phe729 of PDE10A. This study provides valuable insights into the underlying mechanism of selective inhibition targeting PDE9A and PDE10A, for further search for potent and highly selective PDE9A/10A inhibitors.
Anaplastic lymphoma kinase (ALK)-positive anaplastic large cell lymphoma (ALK + ALCL) is most frequent in youth and possesses a broad morphologic spectrum. However, involvement in central nervous ...system (CNS) is definitely rare. The case we presented was a 12-year-old Chinese male who presented with headache and emesis for a couple of days. The neoplastic component was smaller cells resembling starry-sky growth pattern and immunohistochemical stained positively for CD30, ALK1, and CD56. Monoclonal T-cell receptor (TCRγ) gene rearrangement and gene translocation involving ALK identified by fluorescence in situ hybridization (FISH) using ALK break apart probe supported the diagnosis of ALK + ALCL. This case showed ALK + ALCL occur in a rare site with an abnormal CD56 expression. Awareness of this entity is important to distinguish it from other intracranial lymphoma.
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