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To investigate the value of computed tomography (CT) radiomics nomogram in the preoperative prediction of perineural invasion (PNI) in oesophageal squamous cell carcinoma (ESCC) through a multicenter study. We retrospectively collected postoperative pathological data of 360 ESCC patients with definite PNI status (131 PNI-positive and 229 PNI-negative) from two centres. Radiomic features were extracted from the arterial-phase CT images, and the least absolute shrinkage and selection operator and logistic regression algorithm were used to screen valuable features for identifying the PNI status and calculating the radiomics score (Rad-score). A radiomics nomogram was established by integrating the Rad-score and clinical risk factors. A receiver operating characteristic curve was used to evaluate model performance, and decision curve analysis was used to evaluate the predictive performance of the radiomics nomogram in the training, internal validation, and external validation sets. Twenty radiomics features were extracted from a full-volume tumour region of interest to construct the model, and the radiomics nomogram combined with radiomics features and clinical risk factors was superior to the clinical and radiomics models in predicting the PNI status of ESCC patients. The area under the curve values of the radiomics nomogram in the training, internal validation, and external validation sets were 0.856 (0.794–0.918), 0.832 (0.742–0.922), and 0.803 (0.709–0.898), respectively. The radiomics nomogram based on CT has excellent predictive ability; it can non-invasively predict the preoperative PNI status of ESCC patients and provide a basis for preoperative decision-making. [ABSTRACT FROM AUTHOR]

This paper proposes a cam frequency-increasing hybrid piezoelectric electromagnetic energy harvester with center symmetric structure (C-HEH). The use of the cam structure allows the harvester to increase the efficiency of energy harvester per unit time, while the center symmetric structure of the entire harvester allows for maximum energy output in a limited size. This paper studies the influence of the number of cam protrusions and the length of the cylindrical permanent magnet on the output voltage signal at different rotation speeds. When the number of cam protrusions is 3 and the length of the cylindrical magnet is 10 mm, the maximum peak-to-peak voltages of the piezoelectric and the electromagnetic power generation unit are 53.74 V and 3.16 V, respectively. The effective value power of the hybrid energy harvester can be obtained as 1.49 mW. A series of application experiments were carried out to verify the performance of the C-HEH. The hybrid energy harvester can easily light up 86 light-emitting diodes (LEDs) lights and make the scientific calculators work stably after rectification. These results demonstrate the giant prospect of piezoelectric-electromagnetic energy harvesters for supplying wireless sensor networks and low-power electronic devices. [ABSTRACT FROM AUTHOR]

Using perovskite solar cells due to their lightweight, cost-effective, and adaptable nature, is regarded as one of the most encouraging renewable energy options. So, improving the stability of this semiconductor device is very important. One of the suggestions for improving the dynamic stability of this structure is choosing laminated composite layers with various angle ply as the metal layer. So, in this work, for the first time, absorbed energy capacity, and dynamics of improved perovskite solar cells via both mathematical modeling and a hybrid machine learning method is presented. Laminated composite layers are placed in the last layer of the solar cell so that it can improve the energy absorption and dynamics of this kind of semiconductor device. So, with this assumption, in the current work, absorbed energy capacity dynamic deflection and natural frequency sensitivity analysis of solar doubly curved cells with respect to geometrical and physical parameters is carried out. High-order shear deformation theory, which displays the parabolic transverse shear stresses throughout the thickness by satisfying the free surface requirements, is employed in this work to simulate the displacement field. The governing equations with varied boundary conditions are generated and solved, accordingly, using the virtual work principle and exact solution. After obtaining the dataset using mathematical simulation, a hybrid machine learning method using coupled support vector machine (SVM), genetic algorithm (GA), and Particle swarm optimization (PSO) is used to test, train, and validate the outputs. After that, the SVM-PSO-GA algorithm is used to validate the current work's results. Lastly, some detailed recommendations for enhancing the stability of solar cells are provided. [ABSTRACT FROM AUTHOR]

Designing efficient semiconductors for photocatalytic oxygen reduction reaction (ORR) without sacrificial agent is an urgent challenge for H 2 O 2 production under ambient condition. Graphite carbon nitride (g-C 3 N 4) exhibits controllable regulation in band structure and light absorption for photocatalytic process. However, the photocatalytic H 2 O 2 synthesis by pristine g-C 3 N 4 is poor due to the fast recombination of photogenerated carriers and unfavorable selectivity of ORR. To enhance the photocatalytic H 2 O 2 production, different types of carbon can use in combination with g-C 3 N 4. In the present work, we show how cellulose fiber from bamboo can lead to hybrid C/ g-C 3 N 4 photocatalyst with enhanced photocatalytic activity and H 2 O 2 production rate of 121.75 μmol·L−1·h−1, which is 6.2-fold higher than that of pure g-C 3 N 4 without any sacrificial agent. The experimental results confirmed that TEMPO-cellulose derived hydrophilic carbon can not only accelerate the transfer of photo-generated electrons as well as efficient charge carrier separation, but also promote the sequential two-step single-electron ORR route. Thus, this work provides a pioneering perspective for tuning the electronic interaction between g-C 3 N 4 and cellulosic carbon for enhanced photocatalytic H 2 O 2 synthesis. • A novel hybrid C/g-C 3 N 4 photocatalyst was achieved. • Remarkable photocatalytic H 2 O 2 production C/g-C 3 N 4 was revealed. • Enhanced single-electron transfer across C/g-C 3 N 4 heterojunctions. [ABSTRACT FROM AUTHOR]

Global efforts are being made to achieve ecological sustainability while reducing the consequences of environmental degradation. We used panel data from Brazil, Russia, India, China, and South Africa (BRICS countries), spanning 2000 to 2020, to examine the interactions between economic growth, green financing, green credit, renewable energy investment, geopolitical risk (GPR), and environmental sustainability. To explore the short- and long-term connections between the series, we used the cross-sectional augmented distributed lag (CS-ARDL) econometric method. We found that increasing green financing, renewable energy investment, and energy innovation by 0.05% reduced environmental pollution. Moreover, GPR shocks have long-term beneficial effects on green finance development. We also found that the adoption of renewable energy in BRICS countries is significantly and favourably impacted by GPR. This study is groundbreaking because it is the first to examine the interplay between green financing, geopolitical risk, and environmental tax nexus in renewable energy investments, all of which play critical roles in achieving ecological sustainability and yield valuable insights for policymakers working towards the realization of sustainable development goals. • To explore the short- and long-term connections this study used the CS-ARDL econometrics method. • It has been shown that GPR shocks have long-term beneficial effects on green finance development. • We discover that adopting renewable energy in the BRICS is significantly impacted by GPR. [ABSTRACT FROM AUTHOR]

Rational design of efficient semiconductors for photocatalytic nitrogen fixation is an urgent challenge for artificial ammonia (NH 3) production under mild condition. Recently, graphitic carbon nitride (g-C 3 N 4 , CN) shows fascinating potential in photocatalytic nitrogen fixation under visible light. However, compared with other catalysts, the low NH 3 production with pure CN leads to the restriction of practical application. Herein, we covalently coupled covalent organic frameworks (Tptta-COF) and carboxylated carbon nanotubes (CNT) onto CN with amido-linkage and imine-linkage, respectively, through the hydrothermal reaction. Compared with the pristine CN, the obtained COF/CN/CNT achieved larger specific surface area, more visible light absorption and more efficient separation of the photo-generated carriers. The optimal catalyst (COF/CN/CNT) exhibited enhanced photocatalytic activity with NH 3 conversion of 864 μmol·g−1 within 4 h under visible light illumination. Moreover, the introduction of COF and CNT results in a 6.20 times improved photocatalytic NH 3 conversion rate (211 μmol·g−1·h−1) under visible light in contrast to that of the pure CN. The boosting NH 3 production is due to the dual covalent decoration effect of COF and CNT. On the one hand, the COF introduction is favorable for the regulation of band gap, promoting specific surface area as well as N 2 adsorption ability. On the other hand, the CNT introduction not only enhances optical light harvesting, but also accelerates the transfer of photo-excited electron, maintaining high efficient separation of photo-generated carriers. This dual covalent decoration, therefore, shows a potential as a feasible strategy of combining light-harvesting and charge transfer for efficient NH 3 production. [Display omitted] • Tptta-COF/CNT dual coupling with g-C 3 N 4 was achieved. • Intensified specific surface area and electron transfer across COF/CN/CNT heterojunctions. • Abundant light absorption and narrowband gap were regulated by COF and CNT. • Enhanced photocatalytic nitrogen fixation by COF/CN/CNT heterojunctions was revealed. [ABSTRACT FROM AUTHOR]

• Suction-repulsion action of magnetic force complete energy harvester. • Prototype increase the reliability of system compared with collision structure. • Hybrid mechanism solves the power limitation problem and improves output power. In this paper, a hybrid piezoelectric-electromagnetic energy harvester (HEH) based on magnetic couple suction-repulsion motion and centrifugal action is proposed. Using a control variable approach, the effect of two variables on the output performance was investigated under different parameter conditions in order to maximize the output power. At a mounting angle of 60 degrees for the piezoelectric cantilever beam and a mass of 3.2 g for the rectangular magnet, the entire piezoelectric-electromagnetic harvester can produce 13.32 mW of power, which can successfully power low-power electronic devices such as light-emitting diodes (LEDs). The power generated by mixing piezoelectricity and electromagnetism is 1.16 times greater than the power generated by the piezoelectric generation unit alone and 70.1 times greater than the power generated by the electromagnetic generation unit alone. The composite piezoelectric-electromagnetic hybrid mechanism greatly increases the power output of the entire structure compared to the single generation mode. The suction-repulsion process is accomplished using magnetic coupling. This makes the piezoelectric cantilever beam deformed by the magnetic force and has power output. At the same time, the magnetic suction-repulsion makes the circular magnet complete cutting magnetic induction line motion at the same time, which cleverly combines piezoelectricity and electromagnetism. The form of reciprocating motion of the magnet in the coil frame using suction-repulsion is also proposed for the first time. In addition, compared with those structures that strike the piezoelectric cantilever to generate electricity, this paper uses magnetic coupling, which makes the piezoelectric cantilever beam more durable and longer in use. In summary, this structure has good prospects for application in the direction of powering wireless networks or low-power electronic devices. [ABSTRACT FROM AUTHOR]

• Heat treatment and divalent cations had impact on the aggregation of β-lactoglobulin. • Ca2+ and Zn2+ increased the particle size of β-lactoglobulin aggregates. • Cu2+ effected the conformational structure of β-lactoglobulin strongly. • Free sulfhydryl content was significantly declined after Cu2+ treatment. • Cu2+ enhanced peptic digestion of β-lactoglobulin and decreased its antigenicity. Aggregation of bovine β-lactoglobulin is affected easily by external factors. In this study, effects of metal ions combining with temperature on aggregation of β-lactoglobulin were explored. The conformational characteristics of aggregates were detected by environment scanning electron microscope, CD spectrum and free sulfhydryl group, respectively. Digestive and immunological characteristics were assessed by simulated digestion in vitro and ELISA respectively. The results showed that the morphology of β-lactoglobulin aggregates became more amorphous in Cu2+ and Mg2+ treated samples and more constricted in Zu2+-induced protein. Among them, Cu2+ altered the secondary structure of β-lactoglobulin aggregates and free sulfhydryl content most as well as that in gastric digestion. However, all ion-treated groups had similar digestive stability in intestinal digestion. Specially, Ca2+ and Mg2+ made the antigenicity and potential allergenicity of β-lactoglobulin aggregates decrease, which helps us understand the role of metal ions in immunological characteristics. [ABSTRACT FROM AUTHOR]

Abstract: In this paper, we study the Sobolev’s spaces on time scales and their properties. As applications, we present a recent approach via variational methods and the critical point theory to obtain the existence of solutions for a class of second order Hamiltonian systems on time scales. By establishing a proper variational setting, three existence results for systems under consideration are obtained. Finally, three examples are presented to illustrate the feasibility and effectiveness of the existence results. [Copyright &y& Elsevier]

Abstract: In this paper, a class of second-order Hamiltonian systems with impulsive effects are considered. We establish some sufficient conditions for the existence of solutions for the second-order Hamiltonian systems with impulsive effects where , , are continuous and . The solutions are sought by means of some critical point theorems. Finally, two examples are presented to illustrate the feasibility and effectiveness of our results. [Copyright &y& Elsevier]

Abstract: In this paper, we consider the existence and multiplicity of solutions for some Dirichlet impulsive problems and some existence and multiplicity results are obtained. The solutions are sought by means of Lax–Milgram theorem and some critical theorems. [Copyright &y& Elsevier]

• Using multiple groups of magnet coupling and plucking harvesters driven by inertial wheel. • In contrast to previous study, we have made a parametric study of the piezoelectric energy harvester structure. • It can generate milliwatt-level electrical energy at a smaller resonance frequency. Piezoelectric technology has attracted extensive attention and played an increasingly important role in the aspect of harvesting energy from the environment, which has advantages of simple structure, good performance, and so on. In this study, a multi-group dual piezoelectric energy harvester driven by inertial wheel with magnet coupling and plucking (M−PEH) is proposed. The M−PEH mainly includes a base, supports, piezoelectric patches, magnets, magnets cover, and rotor. This paper studies the series–parallel connection relationship between the circular and rectangular piezoelectric patches in the circumferential direction of the base, and the influence on the peak-to peak voltage when the length of the magnet extending from the surface of the rotor is different. Under the condition of inertial wheel 407 g, the M−PEH is tested and researched from 50 r/min to 600 r/min. After a series of experimental studies at 550 r/min, the peak-to-peak voltages of the circular and rectangular piezoelectric patches are respectively 15.00 V, 28.74 V, and 34.37 V, 67.19 V in the case of parallel and series connection when the length of the magnet protruding from the surface of the rotator is 7 mm. Besides that, under the condition of series connection, it is shown that the root-mean-square voltage and power of the circular and rectangular piezoelectric patches are 3.37 V, 0.054 mW, and 10.03 V, 0.80 mW, respectively at 550 r/min when the resistance is 100 kΩ. It can also easily light 47 light-emitting diodes (LEDs) under the excitation of 550 r/min. Therefore, the M−PEH can effectively collect energy under the drive of the inertia wheel and power the microelectronic devices. [ABSTRACT FROM AUTHOR]

In this paper, we studied the existence of solutions for fractional differential equations of p-Laplacian with instantaneous and non-instantaneous impulses. The existence of solutions for a class of fractional differential equations with instantaneous and non-instantaneous impulses is obtained by using the critical point theory. Finally, an example is given to illustrate the feasibility of the main results. [ABSTRACT FROM AUTHOR]

A mirror-image rotating piezoelectric energy harvester is proposed, and it can adapt to 2.8 m/s — 13.6 m/s wind speed. It is arranged by the mirror image of two piezoelectric elements, so it has multiple resonant frequencies. The multiple resonant frequencies make the bandwidth of the energy harvester be broadened. The force applied on the piezoelectric beam is aperiodic and an evaluable analytical model is established based on Fourier series and superposition principle. The influence of the system parameters on the piezoelectric beam is deduced by the Bernoulli beam formula of axial direction, and a prototype is made for experiment and application. The results show that when the distance between the two magnets is kept at 15 mm, the torsion angle of the blades is 15°, three blades are selected, and the height of each blade is 50 mm, the power generation effect is optimal, and the power can reach 12.5 mW. Under the optimal power, it only takes 100s to charge the capacitor of 220 μF to 15V, the prototype can directly power 98 light emitting diodes (LEDs) and make the calculator work. This technology can also be extended for harvesting water energy. • The mirror image structure has multiple resonant frequencies. • The blades are designed to collect wind energy in multiple directions. • It can be extended to the collection of water energy. • Successfully powering micro and small electronic devices. [ABSTRACT FROM AUTHOR]

Antibiotic resistance genes (ARGs) in environment have gradually engendered extensive concern recently due to the harm caused to environment and human beings. Wastewater treatment plants are considered as important nodes of ARGs controlling and it is of utmost importance to figure out effects and mechanisms of each process, especially disinfections. In this study, three disinfection processes (ultraviolet, chlorination, and ozone) were used to reduce levels of ARGs in secondary effluents from a municipal wastewater treatment plant. Results indicated that the abundance of ARGs decreased exponentially as the dosage increased during the ultraviolet disinfection treatment ( R 2 = 0.68–0.92). In the 0–5 mg/L available chlorine concentrations, with a contact time of 30 min, the abundance of ARGs decreased linearly as the chlorine concentrations increased ( R 2 = 0.77–0.99). In a 2 mg/L concentration of ozone (O 3 ), the abundance of ARGs had higher removal efficiency, but the removal efficiency was not significantly enhanced by increasing the concentration of ozone. However, an experiment using the DNase I treatment showed that UV and ozone disinfection resulted in apoptosis, and the bacterial DNA was released into the environment; ARGs were mostly found as free DNA in the treated wastewater. These results provide insights into behavior of ARGs during disinfection processes in wastewater treatment plants. [ABSTRACT FROM AUTHOR]

This paper presents a harvester that collects vibrational energy. The piezoelectric sheet deforms under mass inertia and then generates electricity according to the piezoelectric effect. At the same time, when designing the equipment, the incentive model is selected as the non-contact type to avoid mechanical collision and wear inside the structure and improve the service life of the device. An equivalent damping analysis is performed for the cantilever and combined with the control equations of the Lagrangian. The simulation analysis obtains the native frequency of the rectangular and circular piezoelectric sheets under the mode analysis. Through experimental proof that the device reaches the maximum output voltage 67.19 V when magnet 1 in the mass mutually repels magnet 1 in the housing and magnet 2 in the mass and magnet 2 in the housing. For an external resistance of 10 KΩ, the maximum power output of the device is 165 mW. The device can convert the vibrational energy in the environment into electricity and supply power to other devices through circuit storage. [ABSTRACT FROM AUTHOR]

This paper proposes a double-acting nonlinear wideband piezoelectric energy harvester under plucking and collision(W-PEH) for energy during rotation. The device is mainly composed of a base, rectangular piezoelectric patches, circular piezoelectric generating units and permanent magnets. The circular power generation units are constructed by using the nonlinear magnetic coupling mechanism and the contact frequency conversion principle. The nonlinearity caused by the magnetic force makes the circular piezoelectric power generation units work stably and efficiently at low speeds. And the contact-type collision excitation enables the circular piezoelectric patches inside the circular piezoelectric generating units to produce greater deformation and output a higher voltage. The rectangular piezoelectric patches are excited by the plucking, and the vibration amplitude is greater at high speeds, and it also produces a higher output voltage. Two different excitations make W-PEH's working frequency band wider, and the overall output voltage is also higher. The electromechanical coupling dynamics model of the system was constructed from Hamilton's principle and the magnetic dipole theory. The experimental results indicate that W-PEH can work effectively in different frequency bands. Under the load of 10 KΩ, the peak-to-peak power of the 150r/min integrated device is 0.350W, and that of the 450r/min integrated device is 0.107W. • Combines a nonlinear magnetic coupling with contact frequency conversion principle. • It works well under both low and high speeds excitation. • Two excitations make W-PEH's working frequency band wider, and the power is higher. • It can supply power for micro-electronic devices. [ABSTRACT FROM AUTHOR]

Circular RNAs (circRNAs) have been emerged as novel regulators in multiple tumorigenesis, including melanoma. CircRNA_0084043 was recently demonstrated to be deregulated in human melanoma cells. Nevertheless, its role and mechanism are largely unrevealed in melanoma. Expression of circ_0084043, miRNA (miR)-429 and tribbles homolog 2 (TRIB2) was detected using reverse transcription-quantitative PCR quantitative PCR (RT-qPCR) and western blotting. Cell proliferation, apoptosis, migration and invasion were measured by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay, flow cytometry and transwell assays, respectively. The activation of Wnt/β-catenin pathway was evaluated by western blotting. The target binding among circ_0084043, miR-429 and TRIB2 was confirmed by dual-luciferase reporter assay and RNA immunoprecipitation. In vivo , mice xenograft model was generated to investigate tumor growth. Expression of circ_0084043 and TRIB2 was upregulated in human melanoma tissues and cell lines. Both circ_0084043 knockdown and TRIB2 silencing could decrease cell proliferation, migration and invasion, but facilitate apoptosis in A375 and SK-MEL-28 cells. Furthermore, TRIB2 restoration partially abrogated the tumor-suppressive role of circ_0084043 knockdown in melanoma cells in vitro. Then, we verified that circ_0084043 positively and physically controlled TRIB2 expression through sponging miR-429. Besides, expression of β-catenin, c-Myc and cyclinD1 was inhibited in A375 and SK-MEL-28 cells when circ_0084043 was knocked down, accompanied with increased miR-429 and decreased TRIB2. Notably, circ_0084043 downregulation impeded tumor growth of A375 cells in vivo. Knockdown of circ_0084043 suppressed the malignant development of melanoma presumably through modulating miR429/TRIB2 axis and inactivating Wnt/β-catenin signaling pathway. [ABSTRACT FROM AUTHOR]