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Flexible pressure and strain sensors have attracted increasing attention with the rapid development of medical and electronic interconnection.Ionic conductive hydrogels demonstrate more potential for flexible electronics sensors because of their excellent physicochemical properties such as biomimetic structures， suitable mechanical properties， and excellent biocompatibility. The classification， preparation methods， characteristics of ionic conductive hydrogels，and their applications in flexible pressure and strain sensors were reviewed. First， the sensing modes of ionic conductive hydrogels in pressure and strain sensors were introduced. Then， according to the different conductive principles， they were divided into three categories：metal ion hydrogels， ionic liquid hydrogels， and polyelectrolyte hydrogels. Their applications and research progress in pressure and strain sensors were systematically introduced from synthesis methods， performance characteristics，and improvement methods.Their potential application prospects and development trends were analyzed. The current challenges were summarized and prospects were made. It was believed that ionic conductive hydrogels still have great exploration space and application potential in intelligent flexible sensing.

Objective Making a reasonable train delay adjustment plan is one of the key tasks to ensure the safe and reliable operation of urban rail transit lines. For those lines with express and local trains running on, it is necessary to study the passengers′ train selection behavior during train delays, and analyze the influence of express and local trains overtaking on their choices as well. Method An analysis is conducted on passenger retention and their train selection behavior during express and local train operation on the line. A simulation algorithm that conforms to the rules of passenger boarding/alighting and their train selection behavior is designed, and a simulation and evaluation model for the operation plan adjustment due to express and local train delay is established. In consideration of the departure time and sequence of the express and local trains, and the overtaking trains and stations, different train delay adjustment plans are developed. The passenger′s travel process under the original operation plan and four delay adjustment plans on Shanghai Metro Line 16 is simulated, and the four delay adjustment plans are comprehensively evaluated. Result & Conclusion The simulation and evaluation model is effective and reliable, which can provide simulation means for urban rail transit operators to evaluate train operation plans, and also provide the basis for improving passenger service level, train capacity utilization rate and train operation plans.

The mixing process of the cathodic jets is an important connection between the metal surface and the plasma arc column, which helps to understand the diffusion mechanism of the vacuum arc and guides the vacuum switch design. The interaction process of double cathode jets is simulated using a 3D magnetohydrodynamic method. This study analyzes the evolution of plasma parameters as the double cathode jets transition from a separated state to a mixed state. The results indicate that a mixed single-peaked jet ultimately forms at the exit when the double cathode jets are present at the inlet of the cathode surface. The transition from the separated state to the mixed state occurs further away from the cathode surface as the inlet current density of the jets increases from 3 to 5 × 109 A/m2. Additionally, the asymmetry in the current density of the double cathode jets causes the peaks of the mixed single-peak current density and ion temperature to be skewed toward the direction of the lower inlet current density. In cases where the inlet current direction is asymmetric, the peaks shift toward the direction where the inlet current is perpendicular to the cathode surface. Furthermore, the outward expansion acceleration trend of the plasma aligns well with the results from single-jet numerical simulations.

Objective To investigate the potential pathogenesis of depression and the improving effect of glutathione (GSH) in the process. Methods Sixty male C57BL/6J mice (6-8 weeks old) were randomly divided into sham operation group (SHAM), post-stroke depression (PSD) group and chronic social defeat depression (CSDS) group, with 20 animals in each group. Open field test, elevated plus maze test, tail suspension test, and sucrose preference test were performed to identify whether they exhibited depressive-like behaviors. After the tissue samples of medial prefrontal cortex (mPFC) were harvested from the 2 models and control mice, neurotransmitter-targeted metabolomics sequencing was carried out. Principal component analysis (PCA) and correlation analysis were performed to explore the expression of metabolites in each group of mice to screen differential metabolites. Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis was used to predict the metabolic pathways related to the depression models. The expression of key differential metabolites related to ferroptosis, including glutathione (GSH), malondialdehyde (MDA) and glutathione peroxidase 4 (GPX4). The effect of exogenous supplementation of GSH was observed by whether the depressive-like behavior of the model mice was improved. Results The results of neurotransmitter-targeted metabolomics analysis showed significant differences in the metabolic levels of the 3 groups of mice. Among the 38 metabolites detected in the mPFC, 6 were specifically decreased in PSD and 4 were specifically decreased in CSDS. GSH, L-tryptophan, and L-lysine were significantly decreased in both PSD and CSDS groups (P < 0.05). KEGG analysis indicated that the main pathways involved in the differential metabolites included GSH metabolism, beta-amino acid metabolism, and alanine, aspartate and glutamate metabolism. GSH/GSSG assay kit indicated that the ratio of reduced GSH/oxidized GSH (GSH/GSSG) in the mPFC of the 2 depression models was significantlly decreased (P < 0.05), and the ferroptosis-related index test found that the 2 depression model mice had increased MDA level and significantly reduced GPX4-positive cells compared with the control group (P < 0.05). Exogenous supplementation of GSH in the depression models extended the open arm time in the elevated plus maze test, increased the central zone time in the open field test (P < 0.05), and reduced the immobility time in the tail suspension test (P < 0.05), significantly improving the depressive-like behaviors. Conclusion There are 13 metabolite imbalances in the brain tissues of PSD and CSDS mice, and ferroptosis triggered by abnormal GSH metabolism may play an important role in the occurrence of depression. Exogenous supplementation of GSH improves depressive-like behaviors in mice.

In recent years, the combined surgery of phacoemulsification, intraocular lens implantation, and goniosychialysis has gradually emerged as a primary and effective approach in treating primary angle-closure glaucoma with cataracts. However, with the continuous progress of medical technology, postoperative intraocular pressure control is no longer the sole pursuit. Patients increasingly aspire to achieve higher postoperative visual quality. In order to ensure that patients attain a better refractive status and higher visual quality postoperatively, it is essential to minimize the negative impact caused by primary angle-closure glaucoma. This involves personalized selection of different intraocular lenses or calculation formulas,etc. Evaluation metrics for visual quality encompass visual acuity, contrast sensitivity, higher-order aberrations, subjective perception, etc. Therefore, this paper provides a comprehensive review of postoperative refractive shift, higher-order aberrations, contrast sensitivity and their influencing factors, and the selection of intraocular lenses for patients undergoing combined surgery for primary angle-closure glaucoma with cataracts.

Background Stroke is an acute cerebrovascular disease in which blood fails to flow into the brain, resulting in damage to brain tissue, with high rates of disability, death, and recurrence, and most of the related studies in Ningxia region are clinical analyses of strokes, which lack trend analysis of stroke hospitalization in Ningxia in recent years. Objective To analyze the disease prevalence characteristics and distribution of stroke hospitalized patients in Ningxia, and provide a basis for the development of comprehensive prevention and treatment measures for stroke. Methods The case home page data of 55 hospitals of traditional Chinese medicine (TCM) and western medicine in Ningxia region were collected, and the data discharged from 2013 to 2019 with a primary diagnosis of stroke [International Classification of Diseases (ICD) -10 coded as I60-I63] were screened and analyzed. SPSS 24.0 software was applied to analyze the differences in gender and age using the chi-square test, and a geographic information system (GIS) was applied to analyze the distribution of stroke hospitalization rate data across Ningxia from 2013 to 2019 using global spatial auto correlation analysis. Results A total of 190 634 stroke patients were finally included. The hospitalization rate of stroke in Ningxia region showed an increasing trend year by year from 2013 to 2019 (hospitalization rates of 24.302/10 000, 30.045/10 000, 34.949/10 000, 39.397/10 000, 44.049/10 000, 47.617/10 000, and 52.944/10 000, respectively, χ2trend=5.982, P=0.014) , and the hospitalization rates were higher during the cold season of each year, with a significant peak in March and a slight decline thereafter. Among the stroke inpatients in Ningxia from 2013 to 2019, there were 167 194 cases of ischemic stroke and 23 440 cases of hemorrhagic stroke; there was significant difference between ischemic stroke and hemorrhagic stroke patients in gender and age (χ2=473.533, 7 518.543, P

Abstract Background The aim of this study was to determine the underlying potential mechanisms and function of DIO3OS, a lincRNA in osteosarcoma and clarify that DIO3OS can be used as a potential diagnostic biomarker and immunotherapeutic target. Methods The expression matrix data and clinical information were obtained from XENA platform of UCSC and GEO database as the test cohorts. The external validation cohort was collected from our hospital. Bioinformatics analysis was used to annotate the biological function of DIO3OS. Immune infiltration and immune checkpoint analysis were applied to evaluate whether DIO3OS can be used as an immunotherapeutic target. ROC curves and AUC were established to assess the diagnostic value of DIO3OS for differentiating patients from other subtypes sarcoma. The expression analysis was detected by qRT-PCR, western blot, and immunohistochemical. Wound healing assay and Transwell assay were applied to determine the migration and invasion function of DIO3OS in osteosarcoma cell lines. The tail vein injection osteosarcoma cells metastases model was used in this research. Results High expression of DIO3OS was identified as a risk lincRNA for predicting overall survival of osteosarcoma in test cohort. The outcomes of experiments in vitro and in vivo showed that low expression of DIO3OS limited osteosarcoma tumor metastasis with inhibiting TGF-β signaling pathway. Immune checkpoint genes (CD200 and TNFRSF25) expressions were inhibited in the low DIO3OS expression group. The DIO3OS expression can be applied to reliably distinguish osteosarcoma from lipomatous neoplasms, myomatous neoplasms, nerve sheath tumors, and synovial-like neoplasms. This result was further validated in the validation cohort. Conclusions In conclusion, our outcomes indicated that DIO3OS is a potential diagnostic and prognostic biomarker of osteosarcoma, emphasizing its potential as a target of immunotherapy to improve the treatment of osteosarcoma through TGF-β signaling pathway. Trial registration number: The present retrospectively study was approved by the Ethics Committee of The Second Affiliated Hospital of Nanchang University [Review (2020) No. (115)].

Fe40Cr25Ni25Al5Ti5 (atom fraction/%) medium entropy alloys (MEAs) were prepared by a vacuum arc-melting furnace with a water-cooled copper mold, and the microstructure, mechanical properties and strengthening deformation mechanism of the alloy in solid solution and annealed states were studied by scanning electron microscopy (SEM), energy spectrometry(EDS), X-ray diffractometer (XRD), transmission electron microscopy(TEM) and tensile testing machine.The results show that the Fe40Cr25Ni25Al5Ti5 medium entropy alloy has FCC+BCC1+BCC2 triple-phase organization of solid solution state, with yield strength of 520 MPa, fracture strength of 852 MPa and elongation of 13%. After annealing at 600 ℃ for 2 h, the phase composition of the alloy has no change, the size of granular BCC2 phase increases, and the volume fraction of FCC zone and BCC zone has no change significantly. The yield strength is 668 MPa, the fracture strength is 1029 MPa, and the elongation is reduced to 9%. The strength of Fe40Cr25Ni25Al5Ti5 alloy originates from the synergistic effect of coherent strengthening, solid solution strengthening and phase boundary strengthening. Dislocation slips are the main deformation mechanism of alloy.

Constructing surface micro/nano structures and preparing nano-coatings could endow the material surface with special performance. In this work, the special functions of surface micro/nano structures, as well as the main methods and processing technologies for preparing surface micro/nano structures and nano-coatings were mainly reviewed. Firstly, the applications of surface micro/nano structures in superhydrophobicity, optical superlens, friction and wear were introduced. Secondly, the research progress of lithography technology, laser processing technology, self-assembly technology, additive manufacturing technology (3D printing), processing methods of surface micro/nano structures and nano-coatings, such as deposition method and sol-gel method, was described, respectively. Finally, the problems and development trend of different preparation methods of surface micro/nano structures and nano-coatings were summarized.

Polyetheretherketone (PEEK) is known as a high-grade engineering plastic with good mechanical properties, chemical stability and biocompatibility. Currently, PEEK materials have been widely used in prosthodontics, such as complete dentures and removable partial dentures. The relevant research shows that PEEK posts are superior to glass fiber posts, which have high tensile bond strength and bending strength. At present, few case reports of PEEK postcores have been published, and clinical case reports suggest that PEEK postcores have good oral prosthetic aesthetics and are ideal and reliable postcore crown materials. However, the preparation and surface treatment methods of PEEK require further refinement. A review of the related properties of PEEK and the prospects of its application in the field of postcore crown restoration will be presented in this paper.

The formulations and approximations of the branch flow model for general (radial and mesh) power networks (General-BranchFlow) are given in this paper. Using different sets of the power flow equations, six formats of the exact General-BranchFlow model are listed. The six formats are mathematically equivalent with each other. Linear approximation and second-order cone programming (SOCP) are then used to derive the six formats of the convex General-BranchFlow model. The branch ampacity constraints considering the shunt conductance and capacitance of the transmission line $\Pi$-model are derived. The key foundation of deriving the ampacity constraints is the correct interpretation of the physical meaning of the transmission line II-model. An exact linear expression of the ampacity constraints of the power loss variable is derived. The applications of the General-BranchFlow model in deriving twelve formats of the exact optimal power flow (OPF) model and twelve formats of the approximate OPF model are formulated and analyzed. Using the Julia programming language, the extensive numerical investigations of all formats of the OPF models show the accuracy and computational efficiency of the General-BranchFlow model. A penalty function based approximation gap reduction method is finally proposed and numerically validated to improve the AC-feasibility of the approximate General-BranchFlow model.

Semiconductor CdS fluorescent quantum dots (QDs) have been widely studied for their excellent optical and electrical properties. There are many mature preparation methods of CdS QDs have been developed. Among these, the ionizing radiation preparation method is generally easy to implement under normal temperature and pressure, it is also safe and effective, and environmentally friendly. The associated ionizing radiation preparation methods for CdS QDs, such as γ-ray radiation preparation and electron beam radiation preparation, are reviewed to provide a reference for the preparation of other fluorescent QDs. The applications of CdS QDs in the fields of photocatalysts, biomedicine, and solar cells, in addition to applications in the field of analysis, are reviewed. In light of the current research status of CdS QDs, the application prospects and development directions of CdS QDs are discussed.

To overcome the disadvantage of regular photocatalysts that lack favorable recyclability, hydrogel has become an excellent carrier for photocatalysts. Hydrogel-based photocatalytic composites have the advantages of super-absorbency and recyclability. They can be widely used in the environmental treatment and in medical and health fields. As one of the preparation methods of hydrogel-based photocatalytic composites, ionizing radiation technology is simple, safe, and pollution-free; it can be applied to the industrial production of hydrogel-based photocatalytic composites. This paper summarizes the characteristics of the ionizing radiation technology, the classification of hydrogel-based photocatalytic composites, and radiation preparation methods and their applications. Further, it provides an outlook on future research directions in light of the current research status of hydrogel-based photocatalytic composites.

A nano-TiO2 layer was coated onto the surface of an Indium Tin Oxide (ITO) conductive glass sheet by electrostatic self-assembly, sol-gel, and impregnation and pull methods. The 3, 4-vinyldioxythiophene (EDOT) monomer was grafted onto the surface by electron-beam radiation grafting. Thus, an ITO-TiO2-PEDOT conductive composite film was successfully prepared. Composite films were characterized by Fourier transform infrared spectrometer, X-ray diffractometry, scanning electron microscopy, and contact angle testing. The conductivity of ITO-TiO2-PEDOT (poly 3,4-ethylenedioxythiophene) conductive composite film reached 4×10‒1 S/cm at a dose of 4 kGy/s, and the absorbed dose was 20 kGy, providing a theoretical reference for studies on composite conductive materials produced by techniques involving radiation.

Hydrogels comprise hydrophilic polymer networks. Owing to their good biocompatibility and hydrophilicity, they are widely used in wound dressings, drug delivery, tissue engineering, bioreactors, contact lenses, and other fields. This article summarizes some typical photocatalysts, photosensitizers, and hydrogel composite materials and their antibacterial activities, as well as the basic mechanisms of photothermal and photodynamic effects. In addition, the advantages of radiation technology for preparing photosensitive antibacterial hydrogels are discussed in detail, along with the applications of hydrogels in various fields and the challenges in their use. Finally, future development of photosensitive antibacterial hydrogels is discussed.

Using polyvinyl alcohol (PVA), highly substituted hydroxypropyl cellulose (HHPC), and graphene oxide (GO) as raw materials, a high-strength GO composite hydrogel was synthesized. The effects of the absorbed dose and GO doping on the mechanical properties of the composite hydrogels were investigated via freeze-thawing and irradiation crosslinking. The effects of GO doping on the microstructure and composition of the HHPC/PVA hydrogel were analyzed using scanning electron microscopy, a material testing machine, X-ray diffraction, Fourier-transform infrared spectroscopy, thermogravimetry, and other characterization methods. For an absorbed dose of 60 kGy and GO filling amount of 0.36 mg/g, the GO/HHPC/PVA composite hydrogel exhibited the highest mechanical strength (up to 3.5 MPa), excellent swelling degree (5.3%), and high gel fraction (81.65%). Therefore, the hydrogel is expected to have applications in fields such as tissue engineering and biomedicine.

Abstract Targeted kinase inhibitors improve the prognosis of lung cancer patients with ALK alterations (ALK+). However, due to the emergence of acquired resistance and varied clinical trajectories, early detection of disease progression is warranted to guide patient management and therapy decisions. We utilized 343 longitudinal plasma DNA samples from 43 ALK+ NSCLC patients receiving ALK-directed therapies to determine molecular progression based on matched panel-based targeted next-generation sequencing (tNGS), and shallow whole-genome sequencing (sWGS). ALK-related alterations were detected in 22 out of 43 (51%) patients. Among 343 longitudinal plasma samples analyzed, 174 (51%) were ctDNA-positive. ALK variant and fusion kinetics generally reflected the disease course. Evidence for early molecular progression was observed in 19 patients (44%). Detection of ctDNA at therapy baseline indicated shorter times to progression compared to cases without mutations at baseline. In patients who succumbed to the disease, ctDNA levels were highly elevated towards the end of life. Our results demonstrate the potential utility of these NGS assays in the clinical management of ALK+ NSCLC.

In this study, the impact of varying spraying current on tribological performance and microstructural properties for coating was investigated. Atmospheric plasma spraying (APS) was used as the technique of depositing coatings on Q235 grade steel (equivalent to ASTM A36 mild steel). The coated samples were characterized using optical microscopy (OM), scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), adhesion testers and microhardness tester. Scratch tests were carried out under ambient and dry environments using a pin-on-plate configuration against Tungsten Carbide (WC) body (pin/stylus) for a constant load. It was found that samples sprayed under higher current had better adhesive bond and erosion wear resistance, they also had the lowest wear loss and least percentage porosity. Additionally, hardness was improved almost 10 times of the base material in comparison to lower current samples. Resumen: En este estudio se investigó el impacto de la corriente de pulverización variable sobre el rendimiento tribológico y las propiedades microestructurales para el recubrimiento del Cr2O3. La pulverización con plasma atmosférico (PPA) se usó como la técnica para depositar recubrimientos de Cr2O3 sobre acero de grado Q235 (equivalente al acero dulce ASTM A36). Las muestras recubiertas se caracterizaron usando microscopía óptica (MO), microscopía electrónica de barrido (MEB), espectroscopia de energía dispersiva (EED), probadores de adherencia y probadores de microdureza. Las pruebas se llevaron a cabo en medios ambientales y secos utilizando una configuración de pin en placa contra el cuerpo de carburo de tungsteno (WC) (pin/stylus) para una carga constante. Se encontró que las muestras rociadas con una corriente más alta tenían un mejor enlace adhesivo y una mejor resistencia al desgaste por erosión, también tenían menor pérdida de desgaste y menor porcentaje de porosidad. Además, se mejoró la dureza casi 10 veces del material base en comparación con muestras de corriente más baja.

Objective To investigate the clinical characteristics and influencing factors of insomnia in perimenopausal women based on polysomnography (PSG). Methods A total of 52 perimenopausal women admitted to our psychological clinic due to insomnia were included in this study. According to the results of Pittsburgh sleep quality index (PSQI), they were divided into study group (PSQI≥7) and control group (PSQI < 7). Sleep status was recorded by polysomnography (PSG), and symptoms related to perimenopausal period were measured by menopause rating scale (MRS).The differences of PSG monitoring sleep-related indicators and MRS results were compared between the 2 groups, and the correlations of each sleep indicator with perimenopausal symptoms were analyzed. Results ① The total sleep time and sleep efficiency were significantly decreased in the perimenopausal women from the study group than those from the control group (P < 0.05). The former group had obviously longer sleep latency and wakefulness time when compared with the latter group (P < 0.05). ② These perimenopausal women had the clinical feature of rapid eye movement (REM) sleep behavior, which were characterized by decreased total time of REM sleep, decreased proportion of REM sleep, prolonged latency of REM sleep, and increased frequency of REM to wakefulness in the study group when compared with the control group (P < 0.05). ③The total MRS score, somatic symptom score, psychological symptom score and genitourinary system score were 26.69±5.13, 9.49±2.92, 10.34±2.95 and 6.86±2.89, respectively, in the study group, which were all higher than those of the control group (P < 0.05). ④The proportion of REM sleep and the total time of REM sleep were negatively correlated with depression (P < 0.05), while the latency of REM sleep was positively correlated with anxiety and sexual life quality (P < 0.05). Conclusion Insomnia in perimenopausal women is characterized by REM sleep disorder, and REM sleep is closely related to anxiety, depression and sexual life quality.

This paper informs the design guidelines, fabrication process, and evaluation of a 1.7-kV and 300-A multi-chip half bridge power module using the novel Si-IGBT and SiC-MOSFET hybrid switch in each switch position. The module achieves its maximum DC current rating with a 6:1 current ratio of Si to SiC. This high current ratio yields significant cost savings compared to an all-SiC power module. The module employs high-reliability silver clips, which replaces conventional wire bonds for top-side interconnection, to partly enable a low power loop inductance of 12.38 nH. A novel thermal pyrolytic graphite-encapsulated metal baseplate is key to reducing the thermal coupling among the adjacent Si and SiC die, enabling higher junction temperature for SiC die relative to the Si die.

Polyimide is often used as the insulating material of the repulsion coil, which needs to withstand the collision of the fast repulsion mechanism in high-speed motion and temperature rise. The polyimide molecular model was established in this study. The external electric field was applied to the model through the semi-empirical method to calculate the total molecular energy, dipole moment, molecular orbital energy, and energy gap of polyimide. It was found that the total molecular energy of plasma-modified polyimide was lower, the energy gap was smaller, and the corresponding molecular properties were more stable. Then, the cell models of ordinary polyimide and plasma-modified polyimide were established by molecular dynamics simulation. The effects of plasma modification on the micro properties of polyimide were studied and compared. The free volume, mean square displacement, cohesive energy density, mechanical properties, and relative dielectric constant of polyimide models with different modified ratios were calculated. The results show that the introduction of polar groups through plasma modification can inhibit the movement of the polyimide molecular chain and improve the thermal stability of the polyimide system. The mechanical properties of polyimide are also improved due to plasma modification, and the elastic modulus is the largest when the modification rate is 20%. At the same time, the relative dielectric constant of polyimide increases with the increase of the modification rate.

Morchella is a genus of fungi with the ability to concentrate Cd both in the fruit-body and mycelium. However, the molecular mechanisms conferring resistance to Cd stress in Morchella are unknown. Here, RNA-based transcriptomic sequencing was used to identify the genes and pathways involved in Cd tolerance in Morchella spongiola. 7444 differentially expressed genes (DEGs) were identified by cultivating M. spongiola in media containing 0.15, 0.90, or 1.50 mg/L Cd2+. The DEGs were divided into six sub-clusters based on their global expression profiles. GO enrichment analysis indicated that numerous DEGs were associated with catalytic activity, cell cycle control, and the ribosome. KEGG enrichment analysis showed that the main pathways under Cd stress were MAPK signaling, oxidative phosphorylation, pyruvate metabolism, and propanoate metabolism. In addition, several DEGs encoding ion transporters, enzymatic/non-enzymatic antioxidants, and transcription factors were identified. Based on these results, a preliminary gene regulatory network was firstly proposed to illustrate the molecular mechanisms of Cd detoxification in M. spongiola. These results provide valuable insights into the Cd tolerance mechanism of M. spongiola and constitute a robust foundation for further studies on detoxification mechanisms in macrofungi that could potentially lead to the development of new and improved fungal bioremediation strategies.

The resource utilization of solid waste is an important way to achieve energy saving and emission reduction. A lauric acid (LA)/raw fly ash (RFA)-diatomite(DT)/carbon nanotubes(CNT) composite form-stable phase change materials (FSPCM) for thermal energy storage were prepared via simple direct impregnation method, in which LA, RFA-DT binary matrix and CNT were employed as phase change materials(PCMs), the supporting material, and thermal conductive additive, respectively. The loading capacity, structure and thermal properties of FSCPCM were investigated through the diffusion-oozing testing, Fourier transform infrared spectrometer (FTIR), differential scanning calorimetry (DSC), thermo gravimetry analysis (TGA) and paperless recorder, respectively. The results show that the RFA-DT binary material can effectively prevent the leakage of LA. When the mass fraction of LA in composite is 28%, the FSPCM without leakage can be obtained. What’s more, the utilization rate of RFA reaches 55%. The FTIR demonstrates that FSPCM has good compatibility between its four components, LA, RFA-DT, and CNT. The melting onset temperature of FSPCM is 45.79 ℃ measured by DSC, and the corresponding latent heat of FSPCM is determined as 51.06 J/g. TGA analysis shows LA/RFA-DT has good thermal stability. The storage/release performance curve indicates that when mass fraction of CNT is added with 5%, the melting and solidification time of LA/RFA-DT/CNT are decreased by 60% and 62.5%, respectively, indicating that the heat transfer performance is remarkably improved.

Abstract The direct‐current circuit breaker (DCCB) is the most ideal choice for DC fault isolation in DC grids. Despite a late start, China's research and development on the DCCB have made outstanding achievements. This article provides a brief glance of current China's DCCB development status. It begins by sorting out the technical route according to the topology of DCCB. Then it systematically summarises both mechanical and hybrid DCCBs with focussing on the aspects of topology structure and principle, key technology and characteristics, prototype development and application. It is apparent that Chinese scientists and engineers confronted the worldwide problem of large capacity DC breaking, and put forward a comprehensive solution which consists of an innovative topology structure based on coupled negative voltage circuit, breaking throughs on the key technologies such as highly controllable and reliable fault current commutation, millisecond‐level ultra‐fast and efficient electromagnetic repulsion mechanism, high tolerance and high stability power electronic switch, low residual voltage and fast response energy consumption device, etc. The article states that the world's first set of hybrid high‐voltage (HV) DCCB, and the first set of mechanical HV DCCB have been developed. These DCCBs will soon be deployed to the DC grids which have the highest voltage levels therefore require the strongest breaking capacity. These achievements are leading the world in the development and application of DCCB. The article also discusses the overall development trends of DCCB in the areas of new topologies, key technological breakthroughs and application scenarios, etc. These discussions serve as references for DCCB's future technological advancement and its ever‐expanding applications.

Objective To explore the clinical effect of bulk-fill composite resin combined with transparent preformed crowns for aesthetic restoration of deciduous incisor of children. Methods A predesigned clinical prospective randomized controlled research method was used to select 90 patients (123 teeth). The random number table method was divided into three groups: A, B, and C. Group A was treated with a bulk-fill composite resin of SF (SonicFill) combined with a transparent preformed crown (41 teeth in 30 cases), and group B was treated with a large block of Tetric N-Ceram Bulk Fill Composite resin combined with transparent preformed crowns (39 teeth in 29 cases). Group C was treated with 3M Z350 XT universal nano resin combined with transparent preformed crowns (43 teeth in 31 cases). The visual analog scale (VAS) and the modified USPHS standard were used to evaluate the completeness, marginal steps, marginal discoloration, surface condition, secondary caries and satisfaction of the parents with prostheses after 12 months. Results Twelve months after the operation, the evaluation indexes of group A were better than those of group B and group C, and the differences were statistically significant, including edge integrity (χ2=10.847, P=0.028), edge step (χ2=7.799, P=0.020), edge discoloration (χ2=10.391, P=0.034), surface state (χ2=11.476, P=0.021), and secondary caries (χ2=10.447, P=0.034). The satisfaction of parents in group A on the overall contour (χ2=10.238, P=0.037), shape and texture (χ2=11.521, P=0.021) were better than those in group B and group C, and the differences were statistically significant. There was no significant difference in the evaluation of color satisfaction among the three groups (χ2=0.990, P=0.610). Conclusion SonicFill bulk-fill composite resin combined with transparent preformed crown is good for short-term aesthetic restoration of deciduous incisor, and parental satisfaction is high.

The DC solid state circuit breaker (SSCB) is the key equipment to construct the DC distribution network. In this paper, an improved topological scheme of RC buffer and metal oxide arrester (MOA) in parallel is proposed, which can not only improve the capacity of circuit breaker to cut off large current, but also reduce the pressure of MOA absorbing energy and shorten the time of fault clearing. A 10kV DC SSCB is designed based on the proposed topology, and a model of the influence of different RC buffer parameters on MOA and DC SSCB is built in PSCAD. The simulation results show that the energy absorbed by MOA is linearly decreasing with buffer capacitance Csand total inductance L of the system. As the buffer resistance Rsincreases, the energy absorbed by the MOA decreases first and then increases. Too small snubber resistance will cause the DC SSCB breaking overvoltage and fault current to oscillate; excessive snubber capacitor will cause the DC SSCB breaking overvoltage to be too high. Therefore, it is necessary to select the optimal RC parameters under different fault currents, which can not only reduce the pressure of MOA, but also improve the shutdown capability of DC SSCB.

The flexible DC transmission system needs a DC circuit breaker to remove and isolate the bipolar short-circuit fault to prevent the excessive short-circuit current from damaging the DC transmission system. In this paper, a comprehensive model of DC circuit breaker and transmission system is established by using PSCAD based on capacitive buffered hybrid DC circuit breaker. The short-circuit current waveform and DC port voltage waveform of the three-terminal ±350 kV flexible DC transmission system under the condition of double-pole short-circuit fault at the DC side of rectifier station are simulated and calculated. The simulation results show that the maximum current and voltage of the capacitor-buffering hybrid DC circuit breaker model is lower than that of the ideal DC circuit breaker model under the condition of bipolar short-circuit fault at the DC side of the rectifier station. The system fault waveform under different parameters of capacitor-buffered hybrid DC circuit breaker is compared and analyzed through simulation, so as to optimize the parameters of circuit breaker. It can be seen that the actual results more in line with the switching process can be obtained by using the capacitor buffer type hybrid DC circuit breaker.

With the increase of short circuit current, measures should be taken to reduce the impact. Among various measures, a new technique to interrupt or limit current is proposed and applied to power grid based on high coupled split reactor (HCSR). As the key equipment in new technique, the insulation design of HCSR is a priority. Previous works mainly involve voltage across HCSR in different working states, and take the whole voltages as design requirements. It is rough and takes no account of voltage distribution inside HCSR, thus not suitable for insulation design of HCSR. In order to analyze the overvoltage problems and determine insulation demands for HCSR, this article establishes the equivalent circuit model in turn unit to calculate the voltage distribution inside HCSR, which is simplified and accurate enough for HCSR. A 500 kV AC fault current limiter is briefly introduced, and voltages between turns or arms in HCSR are obtained. The voltage between turns are evenly distributed and voltage between arms are very low under switching impulse. As for lightning impulse, maximum turn-to-turn voltages mainly appear in the end of encapsulations, and the voltage between arms in current sharing state is considerable. This article gives the calculation method and general rules of voltage distribution inside HCSR, and it has great significance for the insulation design of HCSR.

The gas-solid compatibility between environmentally friendly insulating gas and copper contacts is worth studying. In this paper, based on density functional theory, the adsorption calculation of CF3I, c-C4F8, five typical decomposition gases, and Cu (1 1 1) surface was carried out. The adsorption energies, transferred charges, charge densities, and densities of states were calculated for different adsorption configurations. Research indicates that there is no obvious charge transfer between the I atom and the Cu atom in the four adsorption sites of Cu (1 1 1) for the CF3I molecule. There is a charge transfer between the F atoms and the Cu top surface. The electrons lost by Cu are transferred to F atoms. In the configurations of different adsorption positions on CF3I and Cu (1 1 1) planes, the top and bridge adsorption energies are −0.835 eV and −0.993 eV, respectively, which are chemical adsorption. Therefore, CF3I is most likely to form adsorption at the top or bridge site of the Cu (1 1 1) surface. The adsorption energy of c-C4F8 gas on Cu (1 1 1) surface is similar to that of CF3I at fcc and hcp sites. The absolute values are all less than 0.8 eV, and the van der Waals force is the main force. The adsorption energies of C2F4 and C3F6 in the five decomposed gases are −1.315 eV and −1.204 eV, respectively. The charge transfer is −0.32 eV and −0.45 eV, respectively. Their values are larger than those of the other gases studied, which belong to chemical adsorption. The smaller values of the remaining three gases belong to physical adsorption. All molecular structures and Cu (1 1 1) planes were not significantly deformed. From a microscopic point of view, the gas can better exist on the copper surface.

A novel magnetic fluid was obtained using a colloidal dispersion of amorphous magnetic Fe-Ni-B nanoparticles into water. Its magnetorheological and viscoelastic behaviors were all investigated. Results showed that the generated particles were spherical amorphous particles 12–15 nm in diameter. The saturation magnetization of Fe-based amorphous magnetic particles could reach 49.3 emu/g. The amorphous magnetic fluid exhibited shear shinning behavior under magnetic fields and showed strong magnetic responsiveness. The yield stress increased with the rising magnetic field strength. A crossover phenomenon was observed from the modulus strain curves due to the phase transition under applied magnetic fields. The storage modulus G′ was higher than the loss modulus G″ at low strains, while G′ was lower than G″ at high strains. The crossover points shifted to higher strains with increasing magnetic field. Furthermore, G′ decreased and fell off in a power law relationship when the strain exceeded a critical value. However, G″ showed a distinct maximum at a critical strain, and then decreased in a power law fashion. The magnetorheological and viscoelastic behaviors were found to be related to the structural formation and destruction in the magnetic fluids, which is a joint effect of magnetic fields and shear flows.

BackgroundThe electron beams produced by laser plasma acceleration have excellent quality for pulse lengths of the order of fs. Due to the existence of a strong laser field, there are difficulties in direct applications, and more applications need to transmit the electron beams to the application terminal. The energy spread leads to the generation of energy chirp of the electron beam in the transmission.PurposeThis study aims to explore the design of the beam optics to compress the pulse length and keep it on the fs scale.MethodsAn achromatic beamline consisting of bending magnets and quadrupole magnets was designed to compress the pulse length of electron beams. Critical parameters of an achromatic beamline were given by a derived formula. Transformation matrix was employed to investigate the differences of the pulse lengths in achromatic transmission and non-achromatic transmission. The pulse lengths of electron beams with different energies were scanned with different deflection angles (0.3 rad, 0.6 rad, 0.9 rad) and deflection radii (0.15 m, 0.25 m, 0.35 m) to study the influence of beamline parameters. Finally, the magnetic field gradients of the quadrupole lens were adjusted to realize the compression of electron beams with different energies in a beamline.ResultsComparing to non-achromatic transmission, the pulse lengths of electrons with the same energy and different initial divergence angles can be compressed effectively in the achromatic beamline. The larger the deflection angle or the deflection radius, the longer the pulse duration of the electron beam with higher energy (>25 MeV). By adjusting the magnetic field gradients of the quadrupole lens, the pulse lengths can be reduced from more than 100 fs to around 20 fs at higher energies.ConclusionsUsing a fixed-size achromatic beamline, combined with magnetic field strength adjustment, the pulse lengths of electron beams with different energies can be kept on the order of fs after transmission.

To achieve the established carbon emission reduction targets, reduce the intensity of carbon leakage, and protect the EU local enterprise market, in December 2022, the amendment to the EU Carbon Border Adjustment Mechanism (CBAM), which covers key industries such as steel, aluminum products, cement, fertilizer, and electricity, was officially released by the EU Parliament decision and will be officially implemented on October 1, 2023. This study tries to discuss its impact for China—EU trade.

Taking a commercial building in Shanghai as an example, a list of cooling and heating systems are established and operation strategies are formulated. Based on the precondition that the excess electricity can be sold to the grid, the primary energy utilization rate and economices of the energy supply schemes are analyzed. The results show that compared with the traditional heating and cooling supply method, the combined cooling, heating, and power systems have better energy-saving and economic benefits. Additionally, the inclusion of the thermal energy storage yields additional economic benefits (up to 36% reduction in the CO2eq emissions and up to the 21% reduction in the total annual cost). Under the following-electric-load operation mode, the role of the thermal energy storage is to alleviate the temporal mismatch between the electric demand and the heating or cooling demand. To be specific, in the combined cooling, heating, and power systems, the total annual cost is reduced by up to 5.8% and the annual carbon dioxide equivalent emissions are reduced by up to 2.4% when the thermal energy storage is used. While under the following-electric-price operation mode, the performance of the CCHP system is largely subject to the natural gas price. Last, although heat pump systems are often regarded as efficient systems owing to the relatively high coefficient of performance of the heat pump, the energy supply through the heat pump systems may be carbon-emission-intensive currently.

BackgroundG protein subunit gamma 12 (GNG12) is observed in some types of cancer, but its role in osteosarcoma is unknown. This study hypothesized that GNG12 may be a potential biomarker and therapeutic target. We aimed to identify an association between GNG12 and osteosarcoma based on the Gene Expression Omnibus and the Therapeutically Applicable Research to Generate Effective Treatments (TARGET) databases.MethodsOsteosarcoma samples in GSE42352 and TARGET database were selected as the test cohorts. As the external validation cohort, 78 osteosarcoma specimens from The Second Affiliated Hospital of Nanchang University were collected. Patients with osteosarcoma were divided into high and low GNG12 mRNA-expression groups; differentially expressed genes were identified as GNG12-related genes. The biological function of GNG12 was annotated using Gene Ontology, Kyoto Encyclopedia of Genes and Genomes, gene set enrichment analysis, and immune infiltration analysis. Gene expression correlation analysis and competing endogenous RNA regulatory network construction were used to determine potential biological regulatory relationships of GNG12. Overall survival, Kaplan–Meier analysis, and log-rank tests were calculated to determine GNG12 reliability in predicting survival prognosis.ResultsGNG12 expression decreased in osteosarcoma samples. GNG12 was a highly effective biomarker for osteosarcoma [area under the receiver operating characteristic (ROC) curve (AUC) = 0.920], and the results of our Kaplan–Meier analysis indicated that overall survival and progression-free survival differed significantly between low and high GNG-expression group (p < 0.05). Functional analyses indicated that GNG12 may promote osteosarcoma through regulating the endoplasmic reticulum. Expression correlation analysis and competing endogenous RNA network construction showed that HOTTIP/miR-27a-3p may regulate GNG12 expression. Furthermore, the subunit suppresses adaptive immunity via inhibiting M1 and M2 macrophage infiltration. GNG12 was inhibited in metastatic osteosarcoma compared with non-metastatic osteosarcoma, and its expression predicted survival of patients (1, 3, and 5-year AUCs were 0.961, 0.826, and 0.808, respectively).ConclusionThis study identified GNG12 as a potential biomarker for osteosarcoma prognosis, highlighting its potential as an immunotherapy target.

Objective To evaluate the efficacy of hypnosis combined with cognitive behavior therapy for insomnia (CBT-I) in improving the symptoms of patients with chronic insomnia and anxiety. Methods Between March and May, 2018, 48 patients with chronic insomnia and moderate anxiety were recruited from the Psychology Clinic of our center and randomized into the observation group and control group. The patients in the observation group received hypnosis therapy combined with CBT-I for 6 weeks, and those in the control group were treated with CBT-I only. The patients were assessed for anxiety level and sleep quality using Self-Rating Anxiety Scale (SAS) and Pittsburg Sleep Quality Index (PSQI) before and immediately after the intervention, and at 1 month and 3 months after the intervention; Cardiopulmonary Coupling Sleep Quality Assessment System (CPC) was used to measure the sleep onset latency (SOL), time in bed (TIB), total sleep time (TST) and sleep efficiency (SE) of the patients at the same time points. Results At each of the time points after intervention, the patients in the observation group had lower SAS and PSQI scores than those in the control group. Repeated measures analysis of variance showed that the patients in the observation group had significantly better improvement in the anxiety level and sleep quality than the control patients (P < 0.05). The combined therapies also significantly reduced the SOL and increased TST and SE as compared with CBT-I only (P < 0.05). Conclusion Intervention with CBT-I alone has a poor effect on anxiety and an unstable effect on insomnia. The combination of CBT-I with hypnosis can achieve significant improvements in the anxiety level and sleep quality of the patients with long-lasting and stable effects.

In this paper, in accordance with the breaker requirements of a parallel-type circuit breaker based on a high-coupling split reactor, the structure of a coupling reactor is proposed, and the influences of the inner radius, encapsulation height, air ducts width, and encapsulation number of the reactor on coupling factor is analyzed. The reactor design is optimized to minimize metal conductor usage, and the initial design parameters of the coupling reactor are selected based on equal height and heat flux of the coaxial encapsulations. Meanwhile, combined thermal and electromagnetic optimization method and heat load optimization are adopted considering a single-arm limiting current and two-arm flow current working conditions. The optimization results show that the metal conductor usage of the coupling reactor is only 63% compared to a design based on the initial design parameters, and the correctness of the optimization is verified by simulation results.

BackgroundThe detectors of traditional gamma-ray imaging systems cannot meet the radiation detection requirements of positioning for the nuclear industry application. LaBr3(Ce) crystal is a crystal with high light output, very short decay time of luminescence and large density. As a new type of photoelectric conversion device, SiPM has the advantages of small size, anti-magnetic field interference, low power supply voltage, and good time resolution compared with position sensitive photomultiplier tube (PSPMT).PurposeThis study aims to develop a position sensitive detector based on the LaBr3(Ce) crystal coupled with SiPM to achieve high energy resolution, high count rate and miniaturization.MethodsAn 8×8 LaBr3(Ce) crystal array with pixel size 6.4 mm×6.4 mm×20 mm per crystal bar was employed to couple 8×8 SiPM array with silicone grease to form the position sensitive. Then the corresponding readout circuit was designed according to the characteristics of the pulse signal. Finally, 137Cs point sources with different activities were used to test the performance of this detector system and conduct calibration.ResultsTest results show that the average energy resolution of the 64 crystal strips of the detector module is 4.96%, of which the best energy resolution is 3.92% and the worst is 5.91%. Subsequent testing and calibration of the peak position uniformity and sensitivity uniformity of each crystal strip pixel achieve good results.ConclusionsThe position sensitive detector based on the LaBr3(Ce) crystal coupled with SiPM can meet the design requirements of gamma camera imaging in the nuclear industry in terms of energy resolution, peak position uniformity and sensitivity uniformity.

The contact is the core element of the vacuum interrupter of the mechanical DC circuit breaker. The electrical conductivity and welding resistance of the material directly affect its stability and reliability. AgSnO2 contact material has low resistivity, welding resistance, and so on. This material occupies an important position of the circuit breaker contact material. This research is based on the first-principles analysis method of density functional theory. The article calculated the lattice constant, enthalpy change, energy band, electronic density of state, charge density distribution, population, and conductivity of Ce, C single-doped, and Ce-C codoped SnO2 systems. The results show that Ce, C single doping, and Ce-C codoping all increase the cell volume and lattice constant. When the elements are codoped, the enthalpy change is the largest, and the thermal stability is the best. It has the smallest bandgap, the most impurity energy levels, and the least energy required for electronic transitions. The 4f orbital electrons of the Ce atom and the 2p orbital electrons of C are the sources of impurity energy near the Fermi level. When the elements are codoped, more impurity energy levels are generated at the bottom of the conduction band and the top of the valence band. Its bandgap is reduced so conductivity is improved. From the charge density and population analysis, the number of free electrons of Ce atoms and C atoms is redistributed after codoping. It forms a Ce-C covalent bond to further increase the degree of commonality of electrons and enhance the metallicity. The conductivity analysis shows that both single-doped and codoped conductivity have been improved. When the elements are codoped, the conductivity is the largest, and the conductivity is the best.