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Abstract Higher-order topological insulators (HOTIs) are unique materials hosting topologically protected states, whose dimensionality is at least by 2 lower than that of the bulk. Topological states in such insulators may be strongly confined in their corners which leads to considerable enhancement of nonlinear processes involving such states. However, all nonlinear HOTIs demonstrated so far were built on periodic bulk lattice materials. Here, we demonstrate the first nonlinear photonic HOTI with the fractal origin. Despite their fractional effective dimensionality, the HOTIs constructed here on two different types of the Sierpiński gasket waveguide arrays, may support topological corner states for unexpectedly wide range of coupling strengths, even in parameter regions where conventional HOTIs become trivial. We demonstrate thresholdless spatial solitons bifurcating from corner states in nonlinear fractal HOTIs and show that their localization can be efficiently controlled by the input beam power. We observe sharp differences in nonlinear light localization on outer and multiple inner corners and edges representative for these fractal materials. Our findings not only represent a new paradigm for nonlinear topological insulators, but also open new avenues for potential applications of fractal materials to control the light flow.

Abstract Pneumocystis jirovecii is a prevalent opportunistic fungal pathogen that can lead to life-threatening Pneumocystis pneumonia in immunocompromised individuals. Given that timely and accurate diagnosis is essential for initiating prompt treatment and enhancing patient outcomes, it is vital to develop a rapid, simple, and sensitive method for P. jirovecii detection. Herein, we exploited a novel detection method for P. jirovecii by combining recombinase polymerase amplification (RPA) of nucleic acids isothermal amplification and the trans cleavage activity of Cas12a. The factors influencing the efficiency of RPA and Cas12a-mediated trans cleavage reaction, such as RPA primer, crRNA, the ratio of crRNA to Cas12a and ssDNA reporter concentration, were optimized. Our RPA-Cas12a-based fluorescent assay can be completed within 30–40 min, comprising a 25–30 min RPA reaction and a 5–10 min trans cleavage reaction. It can achieve a lower detection threshold of 0.5 copies/µL of target DNA with high specificity. Moreover, our RPA-Cas12a-based fluorescent method was examined using 30 artificial samples and demonstrated high accuracy with a diagnostic accuracy of 93.33%. In conclusion, a novel, rapid, sensitive, and cost-effective RPA-Cas12a-based detection method was developed and demonstrates significant potential for on-site detection of P. jirovecii in resource-limited settings.

For electric vehicles (EVs), it is necessary to improve endurance mileage by improving the efficiency. There exists a trend towards increasing the system voltage and switching frequency, contributing to improve charging speed and power density. However, this trend poses significant challenges for high-voltage and high-frequency motor controllers, which are plagued by increased switching losses and pronounced switching oscillations as consequences of hard switching. The deployment of soft switching technology presents a viable solution to mitigate these issues. This paper reviews the applications of soft switching technologies for three-phase inverters and classifies them based on distinct characteristics. For each type of inverter, the advantages and disadvantages are evaluated. Then, the paper introduces the research progress and control methods of soft switching inverters (SSIs). Moreover, it presents a comparative analysis among the conventional hard switching inverters (HSIs), an active clamping resonant DC link inverter (ACRDCLI) and an auxiliary resonant commuted pole inverter (ARCPI). Finally, the problems and prospects of soft switching technology applied to motor controllers for EVs are put forward.

Abstract Since the oncogenic rearranged during transfection (RET) gene fusion was discovered in non-small cell lung cancer (NSCLC) in 2012, multiple-targeted kinase inhibitors (MKIs) cabozantinib and vandetanib have been explored in the clinic for RET positive NSCLC patients. As the nonselective nature of these inhibitors, patients have off-target adverse effects. The discovery of highly potent selective RET inhibitors such as pralsetinib and selpercatinib improve the clinic efficiency and more favorable toxicity profile. However, acquired resistance mediated by secondary mutations in the solvent-front region of the kinase (e.g. G810C/S/R) become a new challenge for selective RET inhibitor therapies. In this review, we highlight typical RET inhibitors developed during these years and provide a reference for more potential RET inhibitors exploration in the future.

Objective This study ascertained current status and influencing factors of readiness for hospital discharge (RHD) of lung cancer (LC) patients with enhanced recovery after surgery (ERAS) concept-guided postoperative management. Methods This study prospectively and consecutively included 217 LC patients who underwent whole-course ERAS concept-guided postoperative management at the Department of Thoracic Surgery of Guangzhou Institute of Cancer Research, the Affiliated Cancer Hospital, Guangzhou Medical University from November 2023 to April 2024. RHD, quality of discharge teaching (QDT), and social support (SS) were evaluated using RHDS, QDTS, and SSRS, followed by correlation analyses of RHD with the other 2 factors. The clinical baseline and pathological data were compared between the high and low RHD groups, and the characteristics showing statistical significance were assigned as independent variables for regression analysis with RHD as the dependent variable. Results RHD, QDT, and SS were above average among LC patients with ERAS concept-guided postoperative management, and RHD was positively correlated with both QDT and SS. Age, education level, self-care ability, number of admissions, and presence of drainage tubes were independent influence factors for RHD of LC patients with ERAS concept-guided postoperative management. Conclusion In LC patients with ERAS concept-guided postoperative management, RHD may be improved by increasing QDT and SS and intervened by factors such as age, education level, self-care ability, number of admissions, and presence of drainage tubes.

Abstract Human bocavirus (HBoV) 1 is considered an important pathogen that mainly affects infants aged 6–24 months, but preventing viral transmission in resource‐limited regions through rapid and affordable on‐site diagnosis of individuals with early infection of HBoV1 remains somewhat challenging. Herein, we present a novel faster, lower cost, reliable method for the detection of HBoV1, which integrates a recombinase polymerase amplification (RPA) assay with the CRISPR/Cas12a system, designated the RPA‐Cas12a‐fluorescence assay. The RPA‐Cas12a‐fluorescence system can specifically detect target gene levels as low as 0.5 copies of HBoV1 plasmid DNA per microliter within 40 min at 37°C without the need for sophisticated instruments. The method also demonstrates excellent specificity without cross‐reactivity to non‐target pathogens. Furthermore, the method was appraised using 28 clinical samples, and displayed high accuracy with positive and negative predictive agreement of 90.9% and 100%, respectively. Therefore, our proposed rapid and sensitive HBoV1 detection method, the RPA‐Cas12a‐fluorescence assay, shows promising potential for early on‐site diagnosis of HBoV1 infection in the fields of public health and health care. The established RPA‐Cas12a‐fluorescence assay is rapid and reliable method for human bocavirus 1 detection. The RPA‐Cas12a‐fluorescence assay can be completed within 40 min with robust specificity and sensitivity of 0.5 copies/μl.

Abstract Cryptococcus neoformans has been designated as critical fungal pathogens by the World Health Organization, mainly due to limited treatment options and the prevalence of antifungal resistance. Consequently, the utilization of novel antifungal agents is crucial for the effective treatment of C. neoformans infections. This study exposed that the minimum inhibitory concentration (MIC) of isobavachalcone (IBC) against C. neoformans H99 was 8 µg/mL, and IBC dispersed 48-h mature biofilms by affecting cell viability at 16 µg/mL. The antifungal efficacy of IBC was further validated through microscopic observations using specific dyes and in vitro assays, which confirmed the disruption of cell wall/membrane integrity. RNA-Seq analysis was employed to decipher the effect of IBC on the C. neoformans H99 transcriptomic profiles. Real-time quantitative reverse transcription PCR (RT-qPCR) analysis was performed to validate the transcriptomic data and identify the differentially expressed genes. The results showed that IBC exhibited various mechanisms to impede the growth, biofilm formation, and virulence of C. neoformans H99 by modulating multiple dysregulated pathways related to cell wall/membrane, drug resistance, apoptosis, and mitochondrial homeostasis. The transcriptomic findings were corroborated by the antioxidant analyses, antifungal drug sensitivity, molecular docking, capsule, and melanin assays. In vivo antifungal activity analysis demonstrated that IBC extended the lifespan of C. neoformans-infected Caenorhabditis elegans. Overall, the current study unveiled that IBC targeted multiple pathways simultaneously to inhibit growth significantly, biofilm formation, and virulence, as well as to disperse mature biofilms of C. neoformans H99 and induce cell death.

π modes are unique topological edge states appearing in Floquet systems with periodic modulations of the underlying lattice structure in the evolution variable, such as dynamically modulated Su–Schrieffer–Heeger (SSH) lattices. These edge states are anomalous states usually appearing between Floquet replicas of the same band, even if the standard topological index remains zero for this band. While linear and nonlinear π modes were observed in conservative systems, they have never been studied in the nonlinear regime in the non-Hermitian systems with structured gain and losses. Here, we show that the SSH waveguide array with periodically oscillating waveguide positions in the propagation direction and with the parity-time symmetric refractive index landscape can support π modes that are damped or amplified at different ends of the array. By including nonlinearity and nonlinear absorption into our continuous system, we achieve stable lasing in the π mode at one end of the array. The representative feature of this system is that lasing in it is thresholdless and occurs even at low gain–loss amplitudes. The degree of localization of lasing π modes can be flexibly controlled by the amplitude of transverse waveguide oscillations. This work therefore introduces a new type of topological Floquet laser and a route to manipulate π modes by structured gain and losses.

Abstract Abnormal lipid metabolism is an essential hallmark of glioblastoma. Hormone sensitive lipase (HSL), an important rate-limiting enzyme contributed to lipolysis, which was involved in aberrant lipolysis of glioblastoma, however, its definite roles and the relevant regulatory pathway have not been fully elucidated. Our investigations disclosed high expression of HSL in glioblastoma. Knock-down of HSL restrained proliferation, migration, and invasion of glioblastoma cells while adding to FAs could significantly rescue the inhibitory effect of si-HSL on tumor cells. Overexpression of HSL further promoted tumor cell proliferation and invasion. Bioinformatics analysis and dual-luciferase reporter assay were performed to predict and verify the regulatory role of ncRNAs on HSL. Mechanistically, hsa_circ_0021205 regulated HSL expression by sponging miR-195-5p, which further promoted lipolysis and drove the malignant progression of glioblastoma. Besides, hsa_circ_0021205/miR-195-5p/HSL axis activated the epithelial-mesenchymal transition (EMT) signaling pathway. These findings suggested that hsa_circ_0021205 promoted tumorigenesis of glioblastoma through regulation of HSL, and targeting hsa_circ_0021205/miR-195-5p/HSL axis can serve as a promising new strategy against glioblastoma.

Abstract Human rhinovirus B (HRV-B) is a major human viral pathogen that can be responsible for various kinds of infections. Due to the health risks associated with HRV-B, it is therefore crucial to explore a rapid, specific, and sensitive method for surveillance. Herein, we exploited a novel detection method for HRV-B by combining reverse-transcription recombinase polymerase amplification (RT-RPA) of nucleic acids isothermal amplification and the trans-cleavage activity of Cas12a. Our RT-RPA-Cas12a-based fluorescent assay can be completed within 35–45 min and obtain a lower detection threshold to 0.5 copies/µL of target RNA. Meanwhile, crRNA sequences without a specific protospacer adjacent motif can effectively activate the trans-cleavage activity of Cas12a. Moreover, our RT-RPA-Cas12a-based fluorescent method was examined using 30 clinical samples, and exhibited high accuracy with positive and negative predictive agreement of 90% and 100%, respectively. Taken together, a novel promising, rapid and effective RT-RPA-Cas12a-based detection method was explored and shows promising potential for on-site HRV-B infection in resource-limited settings.

Leucine-rich repeat receptor-like kinases (LRR-RLKs) can participate in the regulation of plant growth and development, immunity and signal transduction. Sesamum indicum, one of the most important oil crops, has a significant role in promoting human health. In this study, 175 SiLRR-RLK genes were identified in S. indicum, and they were subdivided into 12 subfamilies by phylogenetic analysis. Gene duplication analysis showed that the expansion of the SiLRR-RLK family members in the sesame was mainly due to segmental duplication. Moreover, the gene expansion of subfamilies IV and III contributed to the perception of stimuli under M. phaseolina stress in the sesame. The collinearity analysis with other plant species revealed that the duplication of SiLRR-RLK genes occurred after the differentiation of dicotyledons and monocotyledons. The expression profile analysis and functional annotation of SiLRR-RLK genes indicated that they play a vital role in biotic stress. Furthermore, the protein−protein interaction and coexpression networks suggested that SiLRR-RLKs contributed to sesame resistance to Macrophomina phaseolina by acting alone or as a polymer with other SiLRR-RLKs. In conclusion, the comprehensive analysis of the SiLRR-RLK gene family provided a framework for further functional studies on SiLRR-RLK genes.

Aiming at the friction heat generation of fuel pump piston oil films for underwater gas turbines, combined with the computational fluid dynamics dynamic grid and slip grid methods, user-defined function programming is performed according to the piston motion equation. Furthermore, a fuel-pump piston oil-film simulation calculation model is established considering the viscosity-temperature characteristics of the oil. A modeling analysis method for the frictional heat generation of the piston oil film is presented. Using the proposed analysis method, the frictional heat generation of the piston oil film was simulated and analyzed, and the influences of the outlet pressure, wall temperature, and rotational speed on the temperature change caused by the oil film frictional heat generation were studied. The following conclusions are obtained. 1) When the inlet pressure was 0.5 MPa, the changes in the outlet pressure had little effect on the temperature rise of the oil film. Moreover, the temperature rise at the top of the oil film was the largest, and the temperature rise could reach up to approximately 4 K at the rate of 2 250 r/min. 2) In the range of 300 K to 373 K, the temperature increase at the top of the oil film decreased by approximately 50% for every 20 K increase in wall temperature. Moreover, the temperature increase at the top of the oil film at 373 K was only 9.2% of that at 300 K. 3) The temperature increase of the oil film and the rotation speed have an approximately linear relationship.

Abstract Chemo-resistance hinders the therapeutic efficacy of temozolomide (TMZ) in treating glioblastoma multiforme (GBM). Recurrence of GBM even after combination of maximal tumor resection, concurrent radio-chemotherapy, and systemic TMZ applocation is inevitable and attributed to the high therapeutic resistance of glioma stem cells (GSCs), which can survive, evolve, and initiate tumor tissue remodeling, the underlying mechanisms of GSCs chemo-resistance, have not been fully elucidated up-to-now. Emerging evidence showed that METTL3-mediated N6-methyladenosine (m6A) modification contributed to the self-renew and radio-resistance in GSCs, however, its role on maintenance of TMZ resistance of GSCs has not been clarified and need further investigations. We found that the cell viability and half-maximal inhibitory concentration (IC50) of GSCs against TMZ significantly decreased after GSCs underwent serum-induced differentiation to adherent growth of tumor cells. Besides, METTL3 expression and total m6A modification declined dramatically in consistence with GSCs differentiation. Knockdown of METTL3 weakened self-renew, proliferation and TMZ IC50 of GSCs, whereas enhanced TMZ induced γH2AX level, indicating upregulation of double-strand DNA damage. We also found that mRNA stability of two critical DNA repair genes (MGMT and APNG) was regulated by METTL3-mediated m6A modification. In conclusion, we speculated that METTL3-mediated m6A modification of MGMT and APNG mRNAs played crucial roles on suppression of TMZ sensitivity of GSCs, which suggest a potential new therapeutic target of METTL3 against GBM.

Abstract Background Integrating CRISPR-Cas12a sensors with isothermal signal amplification can be exploited to develop low-cost, disposable, and ultrasensitive assays for the diagnostics of human pathogens. Methods RT-RAA-Cas12a-mediated real-time or end-point fluorescent and lateral flow strip (LFS) assays for direct detection of norovirus (NOV) genotype GII.4 or GII.17 were explored. Results The results showed that our RT-RAA-Cas12a-mediated fluorescent and LFS assay could detect NOV GII.4 or GII.17 by targeting the viral protein 1 gene. Our RT-RAA-Cas12a-mediated fluorescent and LFS assay can specifically detect NOV GII.4 or GII.17 with no cross-reactivity for other related viruses. The low limit of detection could reach 0.1 copies/μL within approximately 30–40 min, and the results were visualized using an ultraviolet light illuminator or on a LFS without complex equipment. In addition, our RT-RAA-Cas12a-mediated fluorescent and LFS assay provided a visual and faster alternative to real-time RT-PCR assay, with 95.7% and 94.3% positive predictive agreement and 100% negative predictive agreement. Conclusions Together, our RT-RAA-Cas12a-mediated approach would have a great potential for point-of-care diagnostics of NOV GII.4 and/or GII.17 in resource-limited settings.

Potassium (K) channels show the highest variability and most frequent alterations in expression in many tumor types, and modulation of K+ channels may represent a new window for cancer therapy. In previous work, we found that a terahertz (THz) field incident along the z-axis with a frequency of 51.87 THz increased the ion flux through K+ channels. In practice, it is difficult to ensure that the incident electromagnetic (EM) wave is strictly parallel to the direction of channel ion flow. In this paper, we found by changing the direction of the applied electric field that the EM wave of a specific frequency has the largest ion flux when the incident direction is along the ion flow, and the smallest ion flux when the incident direction is perpendicular to the ion flow, and that overall the EM wave of this frequency enhances the ion flow of the K+ channel. Changes in the direction of the applied field at a specific frequency affect the stability of the φ dihedral angle of the GLY77 residue and alter the ion permeation mechanism in the selectivity filter (SF) region, thus affecting the ion flux. Therefore, this frequency can be used to modulate K+ fluxes by THz waves to cause rapid apoptosis in potassium-overloaded tumor cells. This approach consequently represents an important tool for the treatment of cancer and is expected to be applied in practical therapy.

Gliomas are difficult-to-treat brain tumors due to their aggressive nature, rapid proliferation, and high invasiveness (Zhang et al., J Cell Biochem, 2019, 120 (9), 15106–15118; Ge et al., Int J Biochem Cell Biol, 2021, 139, 106054). FOXD3-AS1 has been identified as an emerging potential target for tumor prediction and treatment in many studies (Qin et al., Front Oncol, 2021, 11, 688027). However, the utility of FOXD3-AS1 has not been reported in glioma patients (Li et al., Cancer Manag Res, 2021, 13, 9037–9048). The differential profiles of FOXD3-AS1 in TCGA–GBMLGG database were analyzed across clinical subgroups. The analysis of overall survival (OS), disease-specific survival (DSS), and progression-free interval (PFI) revealed that a high level of FOXD3-AS1 was associated with a poor prognosis and survival outcome. Based on the Cox regression analysis, FOXD3-AS1 was found to be a high-risk factor for glioma that affects prognosis outcomes independently. More importantly, because oxidative stress is closely linked to glioma prognosis, we focused on the potential mechanisms of six oxidative stress co-expressed genes with FOXD3-AS1. In addition, the predictive value of FOXD3-AS1 was determined for each clinical subgroup status. The ROC curve results showed that FOXD3-AS1 had a good predictive performance. A stratified clinicopathological subgroup analysis revealed that high expression of FOXD3-AS1 is associated with a poor prognosis. This also indicates a link between FOXD3-AS1 and tumorigenesis and prognosis, which has potential application value. Furthermore, the immune cell infiltration of FOXD3-AS1 and the signal marker correlation suggested that immune cell infiltration differed significantly between immune cell subsets. To the best of our knowledge, this is the first report to investigate FOXD3-AS1 in glioma and how it may modulate GBM and LGG immune microenvironments. Furthermore, FOXD3-AS1 was detected in tumor and paraneoplastic tissues using RT–qPCR. Transwell analysis verified the migration and invasion of the FOXD3-AS1 knockout group in vitro to a certain extent. In conclusion, FOXD3-AS1 can be used as a prognostic indicator for GBM and LGG, and it is closely related to immune infiltration and response to oxidative stress, which may contribute to the advancement of glioma immunotherapy research.

The structural basis for urokinase-type plasminogen activator receptor (uPAR) dimerization is not understood. Here, the authors solve the crystal structure of soluble uPAR dimers, identifying substantial structural changes compared to the monomer.

Secondary electron emission (SEE) is a fundamental phenomenon of particle/surface interaction, and the multipactor effect induced by SEE can result in disastrous impacts on the performance of microwave devices. To suppress the SEE-induced multipactor, an Ni (111) surface covered with a monolayer of graphene was proposed and studied theoretically via the density functional theory (DFT) method. The calculation results indicated that redistribution of the electron density at the graphene/Ni (111) interface led to variations in the work function and the probability of SEE. To validate the theoretical results, experiments were performed to analyze secondary electron yield (SEY). The measurements showed a significant decrease in the SEY on an Ni (111) surface covered with a monolayer of graphene, accompanied by a decrease in the work function, which is consistent with the statistical evidence of a strong correlation between the work function and SEY of metals. A discussion was given on explaining the experimental phenomenon using theoretical calculation results, where the empty orbitals lead to an electron trapping effect, thereby reducing SEY.

Higher-order topological insulators are unusual materials that can support topologically protected states, whose dimensionality is lower than the dimensionality of the structure at least by 2. Among the most intriguing examples of such states are zero-dimensional corner modes existing in two-dimensional higher-order insulators. In contrast to corner states, recently discovered disclination states also belong to the class of higher-order topological states but are bound to the boundary of the disclination defect of the higher-order topological insulator and can be predicted using the bulk-disclination correspondence principle. Here, we present the first example of the nonlinear photonic disclination state bifurcating from its linear counterpart in the disclination lattice with a pentagonal or heptagonal core. We show that nonlinearity allows us to tune the location of the disclination states in the bandgap and notably affects their shapes. The structure of the disclination lattice is crucial for the stability of these nonlinear topological states: for example, disclination states are stable in the heptagonal lattice and are unstable nearly in the entire gap of the pentagonal lattice. Nonlinear disclination states reported here are thresholdless and can be excited even at low powers. Nonlinear zero-energy states coexisting in these structures with disclination states are also studied. Our results suggest that disclination lattices can be used in the design of various nonlinear topological functional devices, while disclination states supported by them may play an important role in applications, where strong field confinement together with topological protection are important, such as the design of topological lasers and enhancement of generation of high harmonics.

In this paper, the influence of external terahertz electromagnetic fields with different frequencies of 4 THz, 10 THz, 15 THz, and 20 THz on the permeability of the Kv1.2 voltage-gated potassium ion channel on the nerve cell membrane was studied using the combined model of the “Constant Electric Field-Ion Imbalance” method by molecular dynamics. We found that although the applied terahertz electric field does not produce strong resonance with the –C=O groups of the conservative sequence T-V-G-Y-G amino acid residue of the selective filter (SF) of the channel, it would affect the stability of the electrostatic bond between potassium ions and the carbonyl group of T-V-G-Y-G of SF, and it would affect the stability of the hydrogen bond between water molecules and oxygen atoms of the hydroxyl group of the 374THR side chain at the SF entrance, changing the potential and occupied states of ions in the SF and the occurrence probability of the permeation mode of ions and resulting in the change in the permeability of the channel. Compared with no external electric field, when the external electric field with 15 THz frequency is applied, the lifetime of the hydrogen bond is reduced by 29%, the probability of the “soft knock on” mode is decreased by 46.9%, and the ion flux of the channel is activated by 67.7%. Our research results support the view that compared to “direct knock-on”, “soft knock-on” is a slower permeation mode.

Abstract Background The aims of current study were to present the clinical outcomes in patients with pediatric tibia shaft fractures who were treated with unilateral external fixation combined with joystick for fracture reduction and describe the details of our technique. Methods We retrospectively analyzed the patients with pediatric tibia shaft fractures who were treated with unilateral external fixation combined with joystick for fracture reduction between July 2018 and March 2020. The clinical outcomes were evaluated. Results A total of 23 patients were included in the current study with the average age of 8.0 years (ranged 4–14 years). The average duration of hospital and follow-up were 5.9 days (ranged 4–8 days) and 17.4 months (ranged 8–27 months), respectively. At postoperative 3 days, the visual analog scale (VAS) score was 3.1 ± 1.43, which was significantly lower than the preoperative score of 7.3 ± 1.5. Of these, 2 cases showed redness and swelling of pin-tract and exudation at postoperative 1 month, who improved after oral antibiotics without causing fixation failure. The average time to full weight-bearing without crutches was 5.1 weeks (ranged 3–8 weeks). All patients achieved fracture healing and good functional recovery. No complications including fixation failure, reoperation, epiphyseal injury occurred, infection around implants, vessel damage, nerve damage, and limitation of joint movement were observed. The Johner-Wruh scores showed that 21 cases (91.3%) were “excellent” and 2 cases (8.7%) were “good.” Conclusions This procedure had advantages of simple operation, minimum trauma, early recovery of lower limb function, and no risk of complications. It may provide a new choice for children with tibia shaft fractures who require surgical treatment.

The coaxial wiggler with periodic permanent magnet is one of the ways to realize portable and practical high power microwave, which has a relatively small volume and low weight. However, the electromagnetic mode competition will significantly affect the output power at a high electron current. Based on the dispersion curve considering the effect of the electron beam, we propose a method of judging whether the mode can oscillate as the main mode in the coaxial magnetic wiggler. We analyze the wave–beam interaction by the first-order perturbation and predict some modes that seem impossible in traditional methods. It is verified by 3D particle-in-cell simulation that these electromagnetic modes will be the operating modes.

Background: Symptomatic vertebral artery dissecting aneurysm (VADA) is a challenging disease with controversy on treatment strategy due to anatomic configuration and their nature. Moreover, the outcomes of reconstructive treatment have not been well established. Objective: To evaluate the safety and efficacy of reconstructive endovascular treatment (EVT) for symptomatic VADAs with Willis covered stent. Methods: We evaluated retrospectively 13 patients with symptomatic VADAs who treated with Willis covered stent, compared with stent-assisted coiling (SAC) on the characteristics, posttreatment course, angiographic and clinical follow-up outcomes at an average of 14.4 months (range, 3–48 months). Results: A total of 33 patients with symptomatic VADAs were reviewed, 23 of these patients with ruptured VADAs. The technical successful rate is 100% respectively in Willis covered stent (Group A) and SAC (Group B, n ​= ​20). The initial complete occlusion rate was significant higher in group A (100%) than group B (30%) (p ​ ​0.05). No obvious in-stent stenosis and no re-hemorrhage and delayed ischemic symptoms during the follow-up period. The final angiograms of all survived patients demonstrated the complete occlusion rate was higher in group A (100%) than group B (80%), but no significant statistical difference (p ​> ​0.05). Clinical outcomes were favorable in 31 (93.9%), severe disability occurred in one in group B, and only one death in group A. The final clinical outcomes were also not significant difference in the two groups (p ​> ​0.05). Conclusions: Our initial result demonstrated reconstructive EVT with Willis covered stent provides a viable approach for selected symptomatic VADAs involving the intracranial and extracranial segments, which is similar to favorable results with SAC. However, an expanded clinical experiences and larger cohort studies are needed.

This paper for the first time comprehensively presents a multilevel space vector pulse width modulation (SVPWM) method based on the imaginary coordinate system. This method is probably one of the most efficient methods in fast multilevel SVPWMs. It avoids trigonometric operation, look-up tables and only requires simple logic judgement and arithmetic calculation. A distinct advantage of this method over other coordinate-transformation-based methods is that it does not need to transform from the imaginary coordinate system back to the a-b-c (or α-β) coordinate in order to select the redundant vectors using look-up tables. The redundant vectors or zero-sequence components are directly worked out in the proposed method, e.g., for balancing dc-link capacitor voltages, which avoids identifying the starting vector, vector rotation direction (clockwise or anti-clockwise), vector sequence, etc. as used in conventional methods. This paper entails each step to implement this SVPWM method, which can be replicated for multilevel converters with any number of voltage levels. The presented method has been used and validated by various converters, including a three-level and a five-level neutral-point-clamped converter. The archive value of this paper is that it demonstrates a milestone of fast multilevel SVPWM based on coordinate transformation.

The voltage balancing problem of dc-link capacitors in multilevel diode-clamped converters limits their applications in industry under some operational conditions. Virtual vector PWM (VVPWM) can attain the capacitor voltage balancing under all operational conditions but it increases the complexity and computation burden by increasing the number of triangular regions for higher levels as compared to conventional space vector PWM (CSVPWM). In order to solve the dc-link voltage balancing problem in four-level diode-clamped converter, a simplified virtual vector PWM (SVVPWM) algorithm is proposed in this paper. The pair of new virtual vectors is defined in such a way that the space vector diagram of four level converter is transformed into three level space vector diagram that lessens the complexity and computation burden by decreasing the number of triangular regions. The balancing of capacitor voltages can be achieved by using proposed SVVPWM algorithm for the whole range of modulation index load power factor. Steady state and dynamic performance of the SVVPWM algorithm is verified through the simulations and experiments.

Ion transport molecules are involved in many physiological and pathological processes and are considered potential targets for cancer treatment. In the large family of ion transport molecules, potassium (K) ion channels, as surface-expressed proteins, show the highest variability and most frequent expression changes in many tumor types. The key to exploring the permeation of K+ through potassium channels lies in the conserved sequence TVGYG, which is common in the selectivity filter (SF) region of all potassium channels. We found that the K+ flux significantly increased with the help of a specific frequency terahertz electromagnetic wave (51.87 THz) in the KcsA channel using a molecular dynamics combined model through the combined simulation of the constant electric field method and ion imbalance method. This frequency has the strongest absorption peak in the infrared spectrum of -C=O groups in the SF region. With the applied electric field of 51.87 THz, the Y78 residue at the S1 site of the SF has a smaller vibration amplitude and a more stable structure, which enables the K+ to bind closely with the carbonyl oxygen atoms in the SF and realize ion conduction in a more efficient direct Coulomb knock-on.

The current design period for various backward wave oscillators (BWOs) is still at least several months. How to find the best structure parameters with an efficient and stable optimization method is a problem facing researchers in both scientific research and engineering work. In this paper, a non-randomized iterative optimization method is proposed. It applies orthogonal design methods to find local solutions that can provide optimal ‘gradient direction’ for several successive next iteration steps. An evaluation function is designed to distinguish the better ones from the local solutions in the multi-constrained optimization of such BWOs. Optimizations from different starting points are performed separately for a global optimal solution. Two BWOs at different frequency ranges are optimized using the proposed method. The validity and stability of the method are verified. It is believed that the method can provide the global optimum and shorten the design period of THz BWOs.

Acquired chemoresistance is a major limiting factor in the clinical treatment of glioblastoma (GBM). However, the mechanism by which GBM acquires therapeutic resistance remains unclear. Here, we aimed to investigate whether METTL3-mediated N6-methyladenosine (m6A) modification contributes to the temozolomide (TMZ) resistance in GBM. We demonstrated that METTL3 METTL3-mediated m6A modification were significantly elevated in TMZ-resistant GBM cells. Functionally, METTL3 overexpression impaired the TMZ-sensitivity of GBM cells. In contrast, METTL3 silencing or DAA-mediated total methylation inhibition improved the sensitivity of TMZ-resistant GBM cells to TMZ in vitro and in vivo. Furthermore, we found that two critical DNA repair genes (MGMT and APNG) were m6A-modified by METTL3, whereas inhibited by METTL3 silencing or DAA-mediated total methylation inhibition, which is crucial for METTL3-improved TMZ resistance in GBM cells. Collectively, METTL3 acts as a critical promoter of TMZ resistance in glioma and extends the current understanding of m6A related signaling, thereby providing new insights into the field of glioma treatment.

We use a panel data set of 193 countries over 1990–2017 period, by employ the Seemingly unrelated regression (SUR), three stage least squares regression (3SLS), dynamic model two-step generalized method of moments and two-step system generalized method of moments approach to investigate the impacts of financial development, economic growth, energy consumption, and carbon emission on each other. The empirical results suggested that financial development, economic growth, energy consumption, and carbon emissions are affected one another but with high pollution spread, except for consumption of energy which decreases financial development. All models confirm the Environmental Kuznets Curve for the global panel. The implications of all results for carbon emissions, financial development, economic growth, and energy policy are discussed. Keywords: Financial development, Energy consumption, CO2 emissions, Economic growth, Dynamic model two-step GMM and System GMM, Seemingly unrelated regressions (SUR)

This paper presents system-level efficiency evaluation of the suitable isolated dc/dc converters in input-series-output-parallel power electronics transformers (PET) applied for medium-voltage dc systems and provides engineering insights into the design of PETs from a system perspective. To this end, three candidates-a single-stage dual active bridge (DAB) converter, a boost converter plus a DAB with a constant boost output voltage, and a boost converter plus a DAB with a constant DAB voltage gain-are selected and evaluated from a system-level aspect. Comprehensive system-level efficiency comparisons are done with the chosen candidates, considering numbers of normal and hot standby submodules, different working conditions, rated voltages and power of the PET, switching frequencies, and commercial devices. Analysis with detailed loss breakdowns clearly shows the distribution of losses and elaborates the profound reasons behind the efficiency differences. In the comparison, the boost and DAB with a constant boost output voltage have higher or similar efficiency than the other two candidates, verified by simulation and experimental results. Considering its advantages in redundancy in the PET, the boost and DAB with constant boost output voltage are a preferable choice for submodules in input-series-output-parallel PETs.

In urban rail transit, there is a large number of harmonics brought by diode rectifiers, and shunt active power filters (APFs) are an effective method of harmonics rejection. Traditional shunt APFs work with a dedicated DC link leading to complexity, while those with a common DC bus but using non-isolated topologies bring serious problems of zero-sequence circulating current (ZSCC), which introduce losses and provoke poor quality. Consequently, this paper first analyzes the limitations of traditional non-isolated APFs on modulation radio. Based on the analysis, this paper put forward a novel isolated APF with a common DC link based on existing diode rectifiers in urban rail transit, which realizes braking energy recovery as an additional function. To this end, harmonics brought by diode rectifiers are reduced while rejecting ZSCC. Meanwhile, braking energy can feedback to the city grid with lower harmonics. Finally, simulation and experiment using a 1-kW prototype converter verify the feasibility and validity of the proposed converter on harmonics suppression and braking energy recovery.

Hepatocellular carcinoma (HCC) is associated with a high mortality rate worldwide. The therapeutic outcomes can be significantly improved if diagnosis and treatment are initiated earlier in the disease process. Recently, the carboxylesterase (CaE) activity/level in human plasma was reported to be a novel serological biomarker candidate for HCC. In this article, we fabricated a new fluorescent probe with AIE characteristics for the rapid detection of CaE with a more reliable ratiometric response mode. The TCFISE probe showed high sensitivity (LOD: 93.0 μU/mL) and selectivity toward CaE. Furthermore, the good pH stability, superior resistance against photobleaching, and low cytotoxicity highlight the high potential of the TCFISE probe for application in the monitoring of CaE activity in complex biological samples and in live cells, tissues, and animals.

Surface roughening is an important material surface treatment technique, and it is particularly useful for use in secondary electron yield (SEY) suppression on metal surfaces. Porous structures produced via roughening on coatings have been confirmed to reduce SEY, but the regulation strategy and the influence of process parameters both remain unclear in the practical fabrication of effective porous structures. In this paper, the effect of the surface morphology of porous coatings on the SEY of aluminum alloy substrates was studied. Surface characterization and SEY measurements were carried out for samples with a specific process technique on their surfaces. An exponential fitting model of the correlation between surface roughness and the peak values of SEY curves, δm, was summarized. Furthermore, an implementation strategy to enable low surface SEY was achieved from the analysis of the effect of process parameters on surface morphology formation. This work will aid our understanding of the effect of the irregular surface morphology of porous coatings on SEY, thereby revealing low-cost access to the realization of an easy-to-scale process that enables low SEY.

In comparison with conventional lasers, topological lasers are more robust and can be immune to disorder or defects if lasing occurs in topologically protected states. Previously reported topological lasers were almost exclusively based on the first-order photonic topological insulators. Here, we show that lasing can be achieved in the zero-dimensional corner state in a second-order photonic topological insulator, which is based on the Kagome waveguide array with a rhombic configuration. If gain is present in the corner of the structure, where the topological corner state resides, stable lasing in this state is achieved, with the lowest possible threshold, in the presence of uniform losses and two-photon absorption. When gain acts in other corners of the structure, lasing may occur in edge or bulk states, but it requires substantially larger thresholds, and transition to stable lasing occurs over much larger propagation distances, sometimes due to instabilities, which are absent for lasing in corner states. We find that increasing two-photon absorption generally plays strong stabilizing action for nonlinear lasing states. The transition to stable lasing stimulated by noisy inputs is illustrated. Our work demonstrates the realistic setting for corner state lasers based on higher-order topological insulators realized with waveguide arrays.

To explain the sudden jump of pressure as the variation of water depth for a direct-acting relief valve used by torpedo pump as the variation of water depth, a 2-DOF fluid-structure coupling dynamic model is developed. A nonlinear differential pressure model at valve port is applied to model the axial vibration of fluid, and a nonlinear wake oscillator model is used to excite the valve element in the vertical direction; meanwhile, the contact nonlinearity between the valve element and valve seat is also taken into consideration. Based on the developed dynamical model, the water depths for the sudden jumps of pressure can be located precisely when compared with the experimental signals, and the corresponding vibration conditions of the valve element in both the axial and vertical directions are explored. Subsequently, in order to eliminate the sudden jumps of pressure, different pump inlet pressure was tested experimentally; when it was decreased to 0.4 MPa, the pressure jumps ever appeared during the dropping and lifting processes were removed, and the numerical simulation based on the developed mathematical model also verified the experimental measurements.

Cercariae invasion of the human skin is the first step in schistosome infection. Proteases play key roles in this process. However, little is known about the related hydrolytic enzymes in Schistosoma japonicum. Here, we investigated the biochemical features, tissue distribution and biological roles of a cathepsin B cysteine protease, SjCB2, in the invasion process of S. japonicum cercariae. Enzyme activity analysis revealed that recombinant SjCB2 is a typical cysteine protease with optimum temperature and pH for activity at 37°C and 4.0, respectively, and can be totally inhibited by the cysteine protease inhibitor E-64. Immunoblotting showed that both the zymogen (50 kDa) and mature enzyme (30.5 kDa) forms of SjCB2 are expressed in the cercariae. It was observed that SjCB2 localized predominantly in the acetabular glands and their ducts of cercariae, suggesting that the protease could be released during the invasion process. The protease degraded collagen, elastin, keratin, fibronectin, immunoglobulin (A, G and M) and complement C3, protein components of the dermis and immune system. In addition, proteomic analysis demonstrated that SjCB2 can degrade the human epidermis. Furthermore, it was showed that anti-rSjCB2 IgG significantly reduced (22.94%) the ability of the cercariae to invade the skin. The cysteine protease, SjCB2, located in the acetabular glands and their ducts of S. japonicum cercariae. We propose that SjCB2 facilitates skin invasion by degrading the major proteins of the epidermis and dermis. However, this cysteine protease may play additional roles in host-parasite interaction by degrading immunoglobins and complement protein.

Abstract Silicon-rich silicon oxide (SRSO) film was prepared through the deposition of SiOx film by radio-frequency reactive magnetron sputtering from a Si target and the subsequent rapid thermal annealing treatment of SiOx film, and planar-type field emission cathodes based on SRSO film were fabricated. The surface morphologies and electron emission properties of the SRSO films deposited under different O2/Ar flow ratios were investigated. The experimental results show that a relatively high O2/Ar flow ratio during the deposition of SiOx film can lead to the formation of cluster structure in the SRSO film prepared, and the electron emission efficiency of SRSO film rises with the increase of electric field applied. An SRSO-film cathode fabricated under an O2/Ar flow ratio of 1:1 with a chamber pressure of 0.21 Pa has an emission current density of 65.61 μA/cm2 and a corresponding emission efficiency of 0.53% at a bias voltage of 18 V, and it exhibits relatively stable emission and fine emission uniformity.

We study and describe mostly used traditional simplified circuits for full-bridge Zero Voltage Switching-Dual Active Bridge (ZVS-DAB) converter and deduce their mathematical model. On this basis, we propose a high-frequency (HF) mathematical model, which takes into account conduction loss and HF characteristics of the ZVS-DAB converter model. We compare the static and dynamic stabilities of the traditional and the proposed HF mathematical model by simulation. Finally, the high-frequency planar transformer (HFPT) with good heat dissipation and the wide band gap (WBG) semiconductor SiC switches with fast switching speed are employed to build a 4.4 kw, 40 KHz experimental prototype to verify the effectiveness of the improved HF circuit of ZVS-DAB converter. The results show that the proposed HF mathematical model is superior to the traditional one, and it fully considers the HF characteristics of the circuit and effectively improves the HF oscillation, DC bias, and waveform distortion of the ZVS-DAB converter.

ABSTRACT: Background Despite the current availability of flow diverter devices (FDD), problems remains regarding optimal endovascular treatment (EVT) for blood blister-like aneurysms (BBAs) of the internal carotid artery (ICA).Objective To evaluate the safety and efficacy of EVT of BBAs in the ICA with a Willis covered stent.Methods 20 consecutive patients (5 men and 15 women) with ruptured BBAs underwent EVT using a Willis covered stent in two institutions from March 2013 to March 2018. Clinical observations, angiographic characteristics, and procedural and follow-up outcomes were retrospectively evaluated.Results 20 consecutive patients (5 men and 15 women) with ruptured BBAs underwent EVT using a Willis covered stent in two institutions from March 2013 to March 2018. Clinical observations, angiographic characteristics, and procedural and follow-up outcomes were retrospectively evaluated.Conclusion Our initial results demonstrate that reconstructive EVT using a Willis covered stent provides a viable approach to treat ICA BBAs. However, an expanded clinical evaluation and larger cohort are needed to confirm the results. Keywords: blood blister-like aneurysm, endovascular treatment, Willis covered stent

Multiphase machines are gaining increasing popularity because of their distinct advantages over three-phase counterparts, such as reduced per phase power rating, improved reliability and increased degrees of freedom. This paper overviews the development history of multiphase machines and drive techniques in Section II. Three kinds of drive algorithms, including Field-Oriented Control (FOC), Direct Torque Control (DTC) and Model Predictive Control (MPC), are introduced in Section III. Then two types of fault-tolerant methods are compared in Section IV, which are the Vector Space Decomposition (VSD) strategy and Optimal Current Control (OCC) method. Furthermore, different types of existing multiphase converter topologies are listed in Section V, and various kinds of multiphase PWM methods are discussed in Section VI. Finally, based on the review, developing trends of multiphase drive techniques are forecasted.

The interaction of an electromagnetic wave with a relativistic ionization front with frequency up-conversion has been demonstrated by the particle-in-cell (PIC) method. In the PIC simulation, the plasma ionization front is formed by using an electron beam ionizing the background gas. The PIC results are in good agreement with the basic analytic theory. In addition, the charged particles are modulated in the interaction area observed in the PIC simulation, which is hardly obtained by other methods. Based on the verified PIC methods, a relativistic hollow ionization front for frequency up-conversion of microwave to terahertz radiation is proposed for increasing the reflection cross section. Finally, the reflected energy can be increased by at least 3 orders of magnitude compared to the traditional methods.

Candida albicans and Staphylococcus aureus specifically often resulted in biofilm-associated diseases, ranging from superficial mucosal to life-threatening systemic infections. Recent studies reported that chelerythrine displayed antimicrobial activities against a few microorganisms, but its effects on mono- and dual-species biofilms of C. albicans and S. aureus have never been reported. The purpose of this study was to evaluate the efficacy of chelerythrine against mono- and dual-species biofilms, and explore its effect on the hyphal growth and the hypha-to-yeast transition of C. albicans. The results showed that minimum inhibitory concentrations (MICs) and minimum biofilm inhibitory concentration (MBIC90S) of chelerythrine against planktonic cells of mono-species were 4 and 2 μg/mL, while the MIC and MBIC90 were 6 and 3 μg/mL for dual-species. Meanwhile, the decrease in three matrix component levels and tolerance to antibiotics of biofilms formed by mono- and dual-species exposed to chelerythrine were confirmed by a confocal laser scanning microscope, in conjugation with five fluorescent dyes and a gatifloxacin diffusion assay. Moreover, C. albicans and S. aureus mono-species showed a 96.4, and 92.3% reduction, respectively, in 24-h preformed biofilm biomass in the presence of 128 µg/mL of chelerythrine. Similarly, preformed (24 h) dual-species biofilm biomass also displayed a significant reduction (90.7%) when treated with 192 μg/mL chelerythrine. Chelerythrine inhibited hyphae formation of C. albicans at 4 μg/mL, and C. albicans in hypha-form can be converted into yeast-form at 8 μg/mL of chelerythrine. Therefore, chelerythrine shows promise as a potential antimicrobial and antibiofilm agent for clinical effective treatments of mono- and mixed-species and/or biofilm-associated infections.

Previous studies have reported that sanguinarine possesses inhibitory activities against several microorganisms, but its effects on mono- and dual-species biofilms of C. albicans and S. aureus have not been fully elucidated. In this study, we aimed to evaluate the efficacy of sanguinarine for mono- and dual-species biofilms and explore its ability to induce the hypha-to-yeast transition of C. albicans. The results showed that the minimum inhibitory concentration (MIC) and minimum biofilm inhibitory concentration (MBIC90) of sanguinarine against C. albicans and S. aureus mono-species biofilms was 4, and 2 μg/mL, respectively, while the MIC and MBIC90 of sanguinarine against dual-species biofilms was 8, and 4 μg/mL, respectively. The decrease in the levels of matrix component and tolerance to antibiotics of sanguinarine-treated mono- and dual-species biofilms was revealed by confocal laser scanning microscopy combined with fluorescent dyes, and the gatifloxacin diffusion assay, respectively. Meanwhile, sanguinarine at 128 and 256 μg/mL could efficiently eradicate the preformed 24-h biofilms by mono- and dual-species, respectively. Moreover, sanguinarine at 8 μg/mL could result in the transition of C. albicans from the mature hypha form to the unicellular yeast form. Hence, this study provides useful information for the development of new agents to combat mono- and dual-species biofilm-associated infections, caused by C. albicans and S. aureus.

To improve the electron-induced secondary electron emission (SEE) properties of MgO/Au composite film, the strategy of Al doping in the MgO surface layer is adopted and investigated. For an MgO/Au film, Al doping in its MgO surface layer results in a slight increase of its grain size as well as a reduction of its surface roughness according to microstructure characterizations and also causes the decreases of both the band gap and work function of MgO crystal on the basis of the first-principles calculations, all of which have a close relationship with the improvement of secondary electron yield (SEY) demonstrated by the SEE measurement. An MgO/Au film including an Al-doped MgO surface layer with a doping ratio of 4.4% has an SEY of 4.7 with an increase of 14.6% at a primary electron energy (Ep) of 200 eV and the maximum SEY of 10.4 with an increase of 8.3% at Ep of 1100 eV in comparison with an MgO/Au film including an undoped MgO surface layer.

We describe several, recently reported, new topologies and compare them with each other, in order to find out the optimal multilevel grid-connected inverter topology. Then, we classify these topologies according to the basic unit which predecessors proposed. Eventually, we propose the hybrid T-type inverter topology structure, which is composed of two best basic units. This structure takes full advantage of the two components, to reduce the harmonic content and the power loss of the converter and improve the conversion efficiency of the system. At the same time, the space vector pulse width modulation (SVPWM) method is used to simulate the proposed topology in the MATLAB/SIMULINK platform, while the loss of each semiconductor switch is calculated using MELCOSIM software. The results show that the proposed structure is superior to the most widely used topology, i.e., the diode clamped and the T-type three-level circuits.

A scheme to semi-analytically derive waters’ Secchi depth (Zsd) from remote sensing reflectance (Rrs) considering the effects of the residual errors in satellite Rrs was developed for the China Eastern Coastal Zone (CECZ). This approach was evaluated and compared against three existing algorithms using field measurements. As it was challenging to provide the accurately inherent optical properties data for running the three existing algorithms in the extremely turbid waters, the new developed algorithm worked more effective than the latter. Moreover, with both synthetic and match-up data, the results indicated that the proposed algorithm was able to minimize some residual errors in Rrs, and thus could generate inter-mission consistent Zsd results from two ocean color missions. Finally, after application of new model to satellite images, we presented the spatial and temporal variations of Secchi depth and trophic state in the CECZ during 2002−2014. The study led to several findings: Firstly, the Zsd-based trophic state index (TSI) in the East China Sea first increased since 2002, and then gradually dropped during 2008−2014. Secondly, more and more waters within 30−35 m and 20−25 m isobaths were deteriorating from oligotrophic to mesotrophic type and from mesotrophic to eutrophic water, respectively, during 2002−2014. Lastly, the TSI increased on average 0.091 and 0.286 m per year respectively in Bohai Sea and Yellow Sea since 2002, and it might only take 14 and 67 years for Bohai Sea and Yellow Sea to deteriorate from mesotrophic to eutrophic water, following their current yearly deterioration rate and trophic trend. These results highlighted the importance to make some strict regulations for protecting the aquatic environment in the CECZ.

For special instruments or equipments including particle accelerators, space microwave devices and spacecrafts, the suppression for electron-induced secondary electron emission (SEE) occurring on the component surfaces is of great significance due to a negative influence caused by SEE on their normal operations. In this paper, amorphous carbon (a-C) films were prepared on stainless-steel substrates by radio frequency magnetron sputtering, and the effects of substrate temperature (Ts) and continuous electron bombardment on the microstructure and secondary electron emission yield (SEY) of a-C film were investigated in order to achieve a better inhibition for SEE. The experimental results show that a rise of Ts during the a-C film preparation is conducive to a SEY reduction and an increase of multipactor threshold due to the increases of surface roughness and sp2 bond content. In addition, although the SEY of a-C film has a slight increase with the rise of electron bombardment time, the a-C film sample with a lower SEY keeps its lower SEY all the time during continuous electron bombardment. The a-C film prepared at Ts of 500 °C has the lowest SEY peak value of 1.09 with a reduction of 30.6% in comparison with the stainless-steel substrate.