Participation in private tutoring has been a global educational phenomenon and is especially prevalent in China. The present study conducted a student-report questionnaire and collected school ...reports of mathematical achievement to track a year of the longitudinal variation of private tutoring and obtained an analysis of the impact of metacognition on private tutoring participation and its moderating effects between environment-related and initial indicators and mathematical private tutoring participation. The empirical results of this study showed that metacognitive level for learning process monitoring, family economic condition, and mathematics achievement could impact the decision to participate in private tutoring. The results also showed that family economic condition could moderate the effect of metacognitive level for learning process monitoring on the decision to participate in private tutoring. Practical implications for educational competent department and the schoolteachers were discussed.
Non-intrusive load identification plays a crucial role in developing a green and low-carbon energy supply and demand mechanism. Among the various load identification technologies, the low-frequency ...electrical signal load identification stands out due to its ability to discern user's electricity consumption habits without increasing the user's hardware cost, thus presenting promising application prospects. However, the challenge lies in the scarcity of available data and the uneven distribution of samples, resulting in reduced accuracy. In this paper, we present a non-intrusive load state identification method based on the combination of LSTM model and multi-head attention model. By fusing those two techniques, the model can extract and utilize richer and more essential intrinsic features in electrical signals. The use of focal loss can balance the weight importance of different states with significantly different sample numbers. The experimental results on two open data-set show that the proposed algorithm can considerably improve the identification accuracy compared to other NILM methods, and the method also has good practical value in real application.
Plasmid conjugation plays an important role in the dissemination of antibiotic-resistance genes. The emergence of multidrug-resistant isolates of
poses grave challenges in treating infections caused ...by this notorious nosocomial pathogen. Yet, the composition, functionality, and regulation of conjugative machinery utilized by
remain poorly understood. Here, we found that conjugation of the major plasmid pAB3 of
is mediated by a type IVB secretion system similar to the Dot/Icm transporter of
. Furthermore, the expression of the structural genes of the Dot/Icm-like system is co-regulated with genes involved in central metabolism by the GacS/GacA two-component system in response to various metabolites, including intermediates of the tricarboxylic acid cycle. Loss of GacS/A also severely impaired bacterial virulence. These results establish that
coordinates metabolism with plasmid conjugation and virulence by sensing nutrient availability, which may be exploited to develop inhibitory agents for controlling the spread of drug-resistance genes and virulence factors. IMPORTANCE Plasmid conjugation is known to be an energy-expensive process, but our understanding of the molecular linkage between conjugation and metabolism is limited. Our finding reveals that
utilizes a two-component system to co-regulate metabolism, plasmid transfer, and virulence by sensing reaction intermediates of key metabolic pathways, which suggests that nutrient availability dictates not only bacterial proliferation but also horizontal gene transfer. The identification of Dot/Icm-like proteins as components of a conjugation system involved in the dissemination of antibiotic-resistance genes by
has provided important targets for the development of agents capable of inhibiting virulence and the spread of anti-microbial-resistance genes in bacterial communities.
The tumor microenvironment (TME) in pancreatic ductal adenocarcinoma (PDAC) is a complex ecosystem that drives tumor progression; however, in-depth single cell characterization of the PDAC TME and ...its role in response to therapy is lacking. Here, we perform single-cell RNA sequencing on freshly collected human PDAC samples either before or after chemotherapy. Overall, we find a heterogeneous mixture of basal and classical cancer cell subtypes, along with distinct cancer-associated fibroblast and macrophage subpopulations. Strikingly, classical and basal-like cancer cells exhibit similar transcriptional responses to chemotherapy and do not demonstrate a shift towards a basal-like transcriptional program among treated samples. We observe decreased ligand-receptor interactions in treated samples, particularly between TIGIT on CD8 + T cells and its receptor on cancer cells, and identify TIGIT as the major inhibitory checkpoint molecule of CD8 + T cells. Our results suggest that chemotherapy profoundly impacts the PDAC TME and may promote resistance to immunotherapy.
In the realm of cardiac research, the control of spiral waves and turbulent states has been a persistent focus for scholars. Among various avenues of investigation, the modulation of ion currents ...represents a crucial direction. It has been proved that the methods involving combined control of currents are superior to singular approaches. While previous studies have proposed some combination strategies, further reinforcement and supplementation are required, particularly in the context of controlling arrhythmias through the combined regulation of two potassium ion currents. This study employs the Luo–Rudy phase I cardiac model, modulating the maximum conductance of the time-dependent potassium current and the time-independent potassium current, to investigate the effects of this combined modulation on spiral waves and turbulent states. Numerical simulation results indicate that, compared to modulating a single current, combining reductions in the conductance of two potassium ion currents can rapidly control spiral waves and turbulent states in a short duration. This implies that employing blockers for both potassium ion currents concurrently represents a more efficient control strategy. The control outcomes of this study represent a novel and effective combination for antiarrhythmic interventions, offering potential avenues for new antiarrhythmic drug targets.
ATP-binding cassette (ABC) transporters are a large superfamily of membrane proteins that facilitate the translocation of heterogeneous substrates. Studies indicate that ABC transporters may play ...important roles in various carcinomas. However, the correlation between ABC transporters and immunomodulation in thyroid carcinoma (TC), as well as the prognoses for this disease, is poorly understood.TC data from The Cancer Genome Atlas (TCGA) database were used to identify prognostic hallmark ABC transporters associated with immune cell infiltration patterns
via
multiple bioinformatic analyses. Thereafter, quantitative real-time polymerase chain reaction (qRT-PCR) was performed to validate the expression of these selected hallmark ABC transporters in both TC and para-cancerous thyroid tissues. Of a total of 49 ABC transporters, five (
ABCA8
,
ABCA12
,
ABCB6
,
ABCB8
, and
ABCC10
) were identified as hallmark ABC transporters. All five were differentially expressed in TC and associated with the relapse-free survival rates of patients with TC. Immunoregulation by these five hallmark ABC transporters involved the modulation of various aspects of immune cell infiltration, such as hot or cold tumor subsets and the abundances of infiltrating immune cells, as well as specific immunomodulators and chemokines. Besides the diverse significantly correlated factors, the five hallmark ABC transporters and correlated genes were most highly enriched in plasma membrane, transporter activity, and transmembrane transport of small molecules. In addition, many chemicals, namely bisphenol A and vincristine, affected the expression of these five transporters. The qRT-PCR results of collected TC and para-cancerous thyroid tissues were consistent with those of TCGA. The findings in this study may reveal the role played by these five hallmark ABC transporters in regulating immune cell infiltration patterns in TC as well as the molecular mechanisms underlying their functions, leading to a better understanding of their potential prognostic and immunotherapeutic values.
Face regions containing rich semantic information appear frequently in the videos. As the video resolution increase dramatically, the face regions will inevitably attract more attentions. This paper ...proposes a face perception based coding scheme to improve the visual quality of the face regions in UHD videos. A specially tailored face perception model is first utilized to precisely and quickly locate the face regions. Then, a face perception map is generated based on a hierarchical mapping algorithm. Finally, the face perception map is employed as a guidance to optimize the encoding process, including mode decision, block partition and bit allocation. The proposed method is implemented on HEVC to demonstrate the effectiveness. Experimental results on a set of 4K test sequences show that the proposed method can obviously improve the objective and subjective quality of the face regions, while causing only slight quality decline over the rest of the frame. Additionally, the computation required for mode decision and block partition is reduced, thereby saving encoding time cost.
A deep learning based face perception model is designed to fast and accurately detect the faces. Then, a face perception map is generated via a hierarchical mapping algorithm to guide the encoding strategy optimization. Based on the perception map, we simplify the mode decision and block partition processes to achieve a reduced encoding complexity, and we design a QP adaptation mechanism to put more importance on the face regions, thereby improving the perceived quality of the faces.
▶ This work has studied the microstructure and mechanical properties of the as-cast duplex Mg–7Li–
xY alloys with the Y content from 0
wt.% to 7
wt.%. ▶ The microstructure and mechanical properties ...of the T4 and T6 heat-treated duplex Mg–7Li–1Y and Mg–7Li–7Y alloys were also studied. ▶ The solubility of Y element in the Li-based phase has been studied.
Mg–7Li–
xY (
x
=
0–7
wt.%) alloys were prepared by permanent mould casting method, and the microstructure and mechanical properties of the alloys were investigated. The results show that α-Mg and β-Li phases exist in all alloys. The Y-enriched α-Mg phase distributes along the edge of α-Mg phase and in the β matrix of
x
=
1–7 alloys, and Mg
24Y
5 mainly disperses in the β matrix of
x
=
3–7 alloys. The strength of the alloy is enhanced by adding Y element, and the elongation is improved with the Y content no more than 3
wt.%. The as-cast Mg–7Li–3Y alloy exhibits an optimum combination of mechanical properties with the ultimate tensile strength, yield strength and elongation of 160
MPa, 144
MPa and 22%, respectively. After solutionized at 400
°C for 3
h with a subsequent aging at 100
°C, Mg–7Li–7Y alloy exhibits high ultimate tensile strength and yield strength, which are improved to 120% and 152% compared with those of the as-cast Mg–7Li alloy, respectively.
Model predictive control is one of the key technologies to realize the multi-time scale optimal scheduling of integrated energy system. However, the traditional centralized model predictive control ...has the high model order, a large amount of online calculation and is not easy to expand, it is not suitable for the optimal scheduling of an integrated energy system with many distributed units. In this paper, a multi-time scale optimal scheduling method of integrated energy system based on distributed model predictive control is proposed, which realizes the flexible scheduling of the integrated energy system through the coordination and cooperation of various subsystems. Firstly, the detailed models of various generation equipment are established according to the four energy forms of cold, heat, electricity and gas. Then, a multi-time scale optimal scheduling is divided based on three scales: day-ahead long time scale scheduling in 1 h, intra-day predictive control in 15 min and real-time adjustment in 5 min. Next, during the day-ahead scheduling and intra-day rolling optimization, we establish an optimization model based on the best economic operation of the system, the daily operating cost of the system and the minimum penalty cost of start-up and shutdown. During the real-time adjustment, a distributed model predictive control method is proposed to decompose the overall optimization problem of the integrated energy system. Each subsystem estimates the state according to the input sequence of other subsystems at the previous time and optimizes its own performance index. Finally, the case shows that the model predictive control strategy proposed in this paper can increase the speed of optimal operation by about 15% and reduce the cost of optimal operation by about 3.8% compared with the traditional centralized model predictive control method, which not only improves the control performance of system operation, but also improves the economy of system operation.
The efficient coupling between light-harvesting absorbers and cocatalysts allowing for chemical transformation along multielectron pathways is of fundamental importance for the development of ...solar-fuel-producing photochemical systems. Herein we demonstrate that IrO x nanoparticles acting as efficient cocatalyst for water oxidation can be photoelectrochemically deposited from hexahydroxoiridate solutions into the porous structure of TiO2-PH (polyheptazine, “graphitic carbon nitride”) hybrid photoanodes for water photooxidation. As compared to photoanodes loaded with IrO x by the conventional colloidal deposition method, hybrid photoanodes with photodeposited IrO x exhibit significantly enhanced dioxygen evolution under long-term irradiation with visible light (λ > 420 nm). Photocurrent transient measurements show that the undesired accumulation of holes in the TiO2-PH absorber is significantly reduced due to improved coupling between the absorber and the photodeposited cocatalyst. This decreases significantly the recombination rate, leads to more efficient dioxygen evolution, and improves the stability against photocorrosion. Photocurrent measurements under potentiodynamic conditions revealed that at low bias potentials (<0.6 V vs RHE) the photoconversion efficiency of hybrid photoanodes is limited by fast primary back electron transfer and by reduction of Ir(IV) to Ir(III). The performance and stability of hybrid photoanodes are also found to be drastically influenced by the solution chemistry (electrolyte composition and pH). The highest photoconversion efficiency was observed in sulfate-based electrolytes at pH ∼6.
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