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1.
Adv Mater ; : e2101262, 2021 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-34240473

RESUMO

In mammals, physiological respiration involves respiratory cycles of inhaled and exhaled breaths, which has traditionally been an underutilized resource potentially encompassing a wealth of physiologically relevant information as well as clues to potential diseases. Recently, triboelectric nanogenerators (TENGs) have been widely adopted for self-powered respiration monitoring owing to their compelling features, such as decent biocompatibility, wearing comfort, low-cost, and high sensitivity to respiration activities in the aspect of low frequency and slight amplitude body motions. Physiological respiration behaviors and exhaled chemical regents can be precisely and continuously monitored by TENG-based respiration sensors for personalized health care. This article presents an overview of TENG enabled self-powered respiration monitoring, with a focus on the working principle, sensing materials, functional structures, and related applications in both physical respiration motion detection and chemical breath analysis. Concepts and approaches for acquisition of physical information associated with respiratory rate and depth are covered in the first part. Then the sensing mechanism, theoretical modeling, and applications related to detection of chemicals released from breathing gases are systemically summarized. Finally, the opportunities and challenges of triboelectric effect enabled self-powered respiration monitoring are comprehensively discussed and criticized.

2.
Adv Mater ; : e2101449, 2021 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-34240495

RESUMO

The search for ever higher frequency information processing has become an area of intense research activity within the micro, nano, and optoelectronics communities. Compared to conventional semiconductor-based diffusive transport electron devices, electron tunneling devices provide significantly faster response times due to near-instantaneous tunneling that occurs at sub-femtosecond timescales. As a result, the enhanced performance of electron tunneling devices is demonstrated, time and again, to reimagine a wide variety of traditional electronic devices with a variety of new "lightwave electronics" emerging, each capable of reducing the electron transport channel transit time down to attosecond timescales. In response to unprecedented rapid progress within this field, here the current state-of-the-art in electron tunneling devices is reviewed, current challenges and opportunities are highlighted, and possible future research directions are identified.

3.
Front Med ; 2021 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-34241785

RESUMO

Macrolide and corticosteroid resistance has been reported in patients with Mycoplasma pneumoniae (MP) pneumonia (MPP). MP clearance is difficult to achieve through antibiotic treatment in sensitive patients with severe MPP (SMPP). SMPP in children might progress to airway remodeling and even bronchiolitis/bronchitis obliterans. Therefore, identifying serum biomarkers that indicate MPP progression and exploring new targeted drugs for SMPP treatment require urgency. In this study, serum samples were collected from patients with general MPP (GMPP) and SMPP to conduct proteomics profiling. The Fc fragment of the IgG-binding protein (FCGBP) was identified as the most promising indicator of SMPP. Biological enrichment analysis indicated uncontrolled inflammation in SMPP. ELISA results proved that the FCGBP level in patients with SMPP was substantially higher than that in patients with GMPP. Furthermore, the FCGBP levels showed a decreasing trend in patients with GMPP but the opposite trend in patients with SMPP during disease progression. Connectivity map analyses identified 25 possible targeted drugs for SMPP treatment. Among them, a mechanistic target of rapamycin kinase (mTOR) inhibitor, which is a macrolide compound and a cell proliferation inhibitor, was the most promising candidate for targeting SMPP. To our knowledge, this study was the first proteomics-based characterization of patients with SMPP and GMPP.

4.
Phytother Res ; 2021 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-34236105

RESUMO

Erianin is a small-molecule compound that is isolated from Dendrobium chrysotoxum Lindl. In recent years, it has been found to have evident antitumor activity in various cancers, such as bladder cancer, cervical cancer, and nasopharyngeal carcinoma. In this study, we assessed the effect of erianin on lung cancer in terms of cell growth inhibition and the related mechanism. First, erianin at a concentration of less than 1 nmol/L exhibited cytotoxicity in H1975, A549, LLC lung cancer cells, did not cause marked growth inhibition in normal lung and kidney cells, induced obvious apoptosis and G2/M phase arrest of cells, and inhibited the migration and invasion of lung cancer cells in vitro. Second, in a mouse xenograft model of lewis lung cancer (LLC), oral administration of erianin (50, 35, and 10 mg kg-1  day-1 for 12 days) substantially inhibited nodule growth, reduced the fluorescence counts of lewis cells and the percentage vascularity of tumor tissues, increased the number of apoptotic tumor cells, the thymus indices, up-regulated the levels of interleukin (IL)-2 and tumor necrosis factor-α (TNF-α), decreased IL-10 levels and the spleen index, and enhanced immune function. Lastly, the possible targets of erianin were determined by molecular docking and verified via western blot assay. The results indicated that erianin may achieve the above effects via inhibiting the phosphoinositide 3-kinase (PI3K)/Akt/mammalian target of rapamycin (mTOR) pathway in vitro and vivo. Taken together, the results showed that erianin had obvious antitumor effects via inhibiting the PI3K/Akt/mTOR pathway in vitro and vivo and may have potential clinical value for the treatment of lung cancer.

5.
Inorg Chem ; 2021 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-34236180

RESUMO

Zero thermal expansion (ZTE) is an intriguing phenomenon by virtue of its peculiar lack of expansion and contraction with temperature. The achievement of ZTE in a metallic material is a desired but challenging task. Here we report the ZTE behavior of a single-phase metallic VB2 compound, stacking with the V and B atomic layers along the c direction (αV = 2.18 × 10-6 K-1, 5-150 K). Neutron powder diffraction demonstrates that the ZTE behavior is entangled in the direct blocking of the lattice expansion along all crystallographic directions with temperature. X-ray photoelectron spectroscopy and density functional theory calculations indicate that strong covalent binding adheres the nearest-neighbor B-B and V-B pairs, which is proposed to control the ZTE within both the basal plane and the c direction. An intimate correlation is revealed between the covalent binding and the lattice parameters. Our work indicates the opportunity to design metallic ZTE with strong chemical binding in the future.

6.
Radiol Med ; 2021 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-34236572

RESUMO

PURPOSE: To compare predictive efficiency of multiple classifiers modeling and establish a combined magnetic resonance imaging (MRI) radiomics model for identifying lymph node (LN) metastases of papillary thyroid cancer (PTC) preoperatively. MATERIALS AND METHODS: A retrospective analysis based on the preoperative MRI scans of 109 PTC patients including 77 patients with LN metastases and 32 patients without metastases was conducted, and we divided enroll cases into trained group and validation group. Radiomics signatures were selected from fat-suppressed T2-weighted MRI images, and the optimal characteristics were confirmed by spearman correlation test, hypothesis testing and random forest methods, and then, eight predictive models were constructed by eight classifiers. The receiver operating characteristic (ROC) curves analysis were performed to demonstrate the effectiveness of the models. RESULTS: The area under the curve (AUC) of ROC based on MRI texture diagnosed LN status by naked eye was 0.739 (sensitivity = 0.571, specificity = 0.906). Based on the 5 optimal signatures, the best AUC of MRI radiomics model by logistics regression classifier had a considerable prediction performance with AUCs 0.805 in trained group and 0.760 in validation group, respectively, and a combination of best radiomics model with visual diagnosis of MRI texture had a high AUC as 0.969 (sensitivity = 0.938, specificity = 1.000), suggesting combined model had a preferable diagnostic efficiency in evaluating LN metastases of PTC. CONCLUSION: Our combined radiomics model with visual diagnosis could be a potentially effective strategy to preoperatively predict LN metastases in PTC patients before clinical intervention.

7.
Talanta ; 233: 122524, 2021 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-34215027

RESUMO

Covalent organic polymers (COPs) are a promising class of cross-linked polymeric networks that attracted extensive attention in separation and analysis fields. Exploring facile and convenient strategy to prepare COPs-based mixed-mode stationary phases for high performance liquid chromatography (HPLC) has seriously lagged and has never been reported. Herein, we describe a facile in-situ grow strategy for fabrication of silica@COPs core-shell composites (SiO2@TpBD-(OH)2) as a novel mixed-mode stationary phase for HPLC. Owing to the co-existing of abundant hydroxyl, carbonyl, imine, cyclohexyl groups, and benzene rings in the skeleton of COPs shell, the developed mixed-mode stationary phase exhibits hydrophilic interaction liquid chromatography (HILIC)/reversed-phase liquid chromatography (RPLC)/ion-exchange chromatography (IEX) retention mechanisms. The content of acetonitrile, pH value, and salt concentration in the mobile phase were investigated on SiO2@TpBD-(OH)2 packed column. In comparison to conventional single-mode columns, the SiO2@TpBD-(OH)2 column showed flexible selectivity, enhanced separation performance, and superior resolution for benzene homologues, polycyclic aromatic hydrocarbons, nucleosides and bases, and acidic organic compounds. The column efficiency of p-nitrobenzoic acid was up to 54440 plates per meter. The packed column also possessed outstanding chromatographic repeatability for six nucleosides and bases with the RSDs of 0.07-0.23%, 0.58-1.77%, and 0.31-1.23% for retention time, peak area, and peak height, respectively. Besides, the SiO2@TpBD-(OH)2 column offered baseline separation of multiple organic pollutants in lake water, which verified its great potential in real sample analysis. Overall, the silica@COPs core-shell composites not only provide a new candidate of mixed-mode stationary phases, but also extend the potential application of COPs in separation science.


Assuntos
Cromatografia de Fase Reversa , Dióxido de Silício , Cromatografia por Troca Iônica , Interações Hidrofóbicas e Hidrofílicas , Polímeros
8.
BMC Genomics ; 22(1): 503, 2021 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-34217229

RESUMO

BACKGROUND: The dieback epidemic decimating common ash (Fraxinus excelsior) in Europe is caused by the invasive fungus Hymenoscyphus fraxineus. In this study we analyzed the genomes of H. fraxineus and H. albidus, its native but, now essentially displaced, non-pathogenic sister species, and compared them with several other members of Helotiales. The focus of the analyses was to identify signals in the genome that may explain the rapid establishment of H. fraxineus and displacement of H. albidus. RESULTS: The genomes of H. fraxineus and H. albidus showed a high level of synteny and identity. The assembly of H. fraxineus is 13 Mb longer than that of H. albidus', most of this difference can be attributed to higher dispersed repeat content (i.e. transposable elements [TEs]) in H. fraxineus. In general, TE families in H. fraxineus showed more signals of repeat-induced point mutations (RIP) than in H. albidus, especially in Long-terminal repeat (LTR)/Copia and LTR/Gypsy elements. Comparing gene family expansions and 1:1 orthologs, relatively few genes show signs of positive selection between species. However, several of those did appeared to be associated with secondary metabolite genes families, including gene families containing two of the genes in the H. fraxineus-specific, hymenosetin biosynthetic gene cluster (BGC). CONCLUSION: The genomes of H. fraxineus and H. albidus show a high degree of synteny, and are rich in both TEs and BGCs, but the genomic signatures also indicated that H. albidus may be less well equipped to adapt and maintain its ecological niche in a rapidly changing environment.


Assuntos
Elementos de DNA Transponíveis , Fraxinus , Ascomicetos , Europa (Continente) , Fraxinus/genética , Humanos , Doenças das Plantas
9.
Genome Biol ; 22(1): 208, 2021 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-34256818

RESUMO

One challenge facing omics association studies is the loss of statistical power when adjusting for confounders and multiple testing. The traditional statistical procedure involves fitting a confounder-adjusted regression model for each omics feature, followed by multiple testing correction. Here we show that the traditional procedure is not optimal and present a new approach, 2dFDR, a two-dimensional false discovery rate control procedure, for powerful confounder adjustment in multiple testing. Through extensive evaluation, we demonstrate that 2dFDR is more powerful than the traditional procedure, and in the presence of strong confounding and weak signals, the power improvement could be more than 100%.

10.
J Cereb Blood Flow Metab ; : 271678X211028680, 2021 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-34259069

RESUMO

Traumatic brain injury (TBI) is commonly followed by long-term cognitive deficits that severely impact the quality of life in survivors. Recent studies suggest that microglial/macrophage (Mi/MΦ) polarization could have multidimensional impacts on post-TBI neurological outcomes. Here, we report that repetitive intranasal delivery of interleukin-4 (IL-4) nanoparticles for 4 weeks after controlled cortical impact improved hippocampus-dependent spatial and non-spatial cognitive functions in adult C57BL6 mice, as assessed by a battery of neurobehavioral tests for up to 5 weeks after TBI. IL-4-elicited enhancement of cognitive functions was associated with improvements in the integrity of the hippocampus at the functional (e.g., long-term potentiation) and structural levels (CA3 neuronal loss, diffusion tensor imaging of white matter tracts, etc.). Mechanistically, IL-4 increased the expression of PPARγ and arginase-1 within Mi/MΦ, thereby driving microglia toward a global inflammation-resolving phenotype. Notably, IL-4 failed to shift microglial phenotype after TBI in Mi/MΦ-specific PPARγ knockout (mKO) mice, indicating an obligatory role for PPARγ in IL-4-induced Mi/MΦ polarization. Accordingly, post-TBI treatment with IL-4 failed to improve hippocampal integrity or cognitive functions in PPARγ mKO mice. These results demonstrate that administration of exogenous IL-4 nanoparticles stimulates PPARγ-dependent beneficial Mi/MΦ responses, and improves hippocampal function after TBI.

11.
Bioinformatics ; 2021 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-34255026

RESUMO

SUMMARY: PERMANOVA (permutational multivariate analysis of variance based on distances) has been widely used for testing the association between the microbiome and a covariate of interest. Statistical significance is established by permutation, which is computationally intensive for large sample sizes. As large-scale microbiome studies such as American Gut Project (AGP) become increasingly popular, a computationally efficient version of PERMANOVA is much needed. To achieve this end, we derive the asymptotic distribution of the PERMANOVA pseudo-F statistic and provide analytical p-value calculation based on chi-square approximation. We show that the asymptotic p-value is close to the PERMANOVA p-value even under a moderate sample size. Moreover, it is more accurate and an order-of-magnitude faster than the permutation-free method MDMR. We demonstrated the use of our procedure D-MANOVA on the AGP dataset. AVAILABILITY: D-MANOVA is implemented by the dmanova function in the CRAN package GUniFrac. SUPPLEMENTARY INFORMATION: Supplementary data are available at Bioinformatics online.

12.
Artigo em Inglês | MEDLINE | ID: mdl-34278795

RESUMO

The key to unlocking the full potential of two-dimensional (2D) materials in ultrathin opto-electronics is their layer-by-layer integration and the ability to produce them on the wafer scale using traditional industry-compatible technology. Here, we demonstrate a novel stacking method for assembling uniform-patterned periodic 2D arrays into vertical-layered heterostructures. The fabricated heterostructure can serve as photodetectors, with graphene electrodes and transition-metal dichalcogenides as the photo-absorber. All 2D materials used are grown into continuous films with only mono- or bilayer thickness. Each layer is prepatterned into a specific shape on a substrate and then transferred to the device substrate with aligned precision. In order to achieve long-range alignment across the wafer, interlocking marker pairs are used to help guide the lateral accuracy and reduce rotational error. We show hundreds of identical devices produced with 2D periodic spacing on a 1 cm × 1 cm SiO2/Si substrate, a fundamental prerequisite for future pixelated detectors. Statistics of the photovoltaic performance of the devices are reported, with values that are comparable to devices made by chemical vapor deposition-grown materials. Our work provides pathways for the large-scale fabrication of ultrathin all-2D opto-electronics that form the basis of the future in 2D-pixelated cameras and displays.

13.
J Cell Sci ; 2021 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-34279633

RESUMO

The F-BAR protein Imp2 is an important contributor to cytokinesis in the fission yeast, Schizosaccharomyces pombe. Because cell cycle regulated phosphorylation of the central intrinsically disordered region (IDR) of the Imp2 paralog, Cdc15, controls Cdc15 oligomerization state, localization, and ability to bind protein partners, we investigated whether Imp2 is similarly phosphoregulated. We found that Imp2 is endogenously phosphorylated on 28 sites within its IDR with the bulk of phosphorylation being constitutive. In vitro, casein kinase 1 (CK1) Hhp1 and Hhp2 can phosphorylate 17 sites and Cdk1 the remaining 11 sites. Mutations that prevent Cdk1 phosphorylation result in precocious Imp2 recruitment to the cell division site, and mutations designed to mimic these phosphorylation events delay Imp2 CR accumulation. Mutations that eliminated CK1 phosphorylation sites allowed CR sliding, and phosphomimetic substitutions at these sites reduced Imp2 protein levels and slowed CR constriction. Thus, like Cdc15, the Imp2 IDR is phosphorylated at many sites by multiple kinases. In contrast to Cdc15, for which phosphorylation plays a major cell cycle regulatory role, Imp2 phosphorylation is primarily constitutive with milder effects on localization and function.

14.
Ann Palliat Med ; 10(6): 6883-6891, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34237986

RESUMO

BACKGROUND: Our study aims to explore the knowledge, attitude, and practice (KAP) and its influencing factors of medication among residents in Haikou, the capital city of Hainan Province, and inform the development of interventions to reduce residents' medication errors. METHODS: A cross-sectional questionnaire survey was conducted to investigate the KAP of medication among Haikou residents and its influencing factors from March to September 2019. RESULTS: A total of 471 valid questionnaires were collected (245 online and 226 offline), with an effective recovery rate of 94.2%. The average score of KAP of medication were 52.2±13.08, 27.34±8.14, and 51.54±9.22, respectively. The knowledge score reached "good" in the evaluation criteria of the questionnaire, and the attitude and practice scores were "fair". Multiple linear regression analysis revealed the medication knowledge increased with age; a lower education degree was associated with less knowledge and more medication errors, and a higher education level was associated with more access to medication knowledge. CONCLUSIONS: Education on rational drug use should be performed via multiple ways to promote rational drug use and reduce risky medication behaviors, particularly among residents with low education degrees, e.g., drug counseling and guidance, regularly push medication science popularization, public welfare lecture on rational drug use, organize and compile popular science books.


Assuntos
Aconselhamento , Conhecimentos, Atitudes e Prática em Saúde , Estudos Transversais , Humanos , Inquéritos e Questionários
15.
Zhongguo Yi Xue Ke Xue Yuan Xue Bao ; 43(3): 371-381, 2021 Jun 30.
Artigo em Chinês | MEDLINE | ID: mdl-34238413

RESUMO

Objective To explore the function and mechanism of related genes in the occurrence and development of liver cancer, and the possibility of key genes as potential biomarkers and prognostic indicators for the treatment of liver cancer.Methods We selected 4 datasets(GSE57957, GSE121248, GSE36376 and GSE14520)from the GEO database.With P<0.05 and |log2FC|>1 as the thresholds, we used GEO2R and Venn Diagram Software to filter out the common significant differentially expressed genes(DEGs).Cytoscape 3.6.1 plug-ins CytoHubba and molecular complex detection(MCODE)were used to screen out the hub genes and modules of DEGs.In addition, survival analysis of DEGs was performed by gene expression profiling(GEPIA), and Human Protein Atlas(HPA)were used to examine the protein expression levels of key genes in normal liver tissue and liver cancer tissue.Results There were 45 obviously up-regulated genes and 132 down-regulated genes, and MCODE identified 13 clusters.The cluster 1 and cluster 2 with higher scores included 16 genes and 13 genes, respectively.Among the 32 significant DEGs, IGFALS, HGFAC, CYP3A4, SLC22A1, TAT and CYP2E1 demonstrated significantly higher expression levels in liver tissue than in other organs.The HPA immunohistochemistry(IHC)data showed that the expression levels of IGFALS, CYP3A4, SLC22A1 and CYP2E1 in liver cancer tissue were significantly down-regulated and related to the low overall survival rate of patients.Conclusion The liver tissue-specific genes IGFALS, CYP3A4, SLC22A1 and CYP2E1 are under-expressed in liver cancer and associated with poor prognosis, which may be potential biomarkers and prognostic indicators for liver cancer.


Assuntos
Citocromo P-450 CYP2E1 , Neoplasias Hepáticas , Biomarcadores Tumorais/genética , Biologia Computacional , Citocromo P-450 CYP3A , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Redes Reguladoras de Genes , Humanos , Neoplasias Hepáticas/genética , Prognóstico , Mapas de Interação de Proteínas
16.
Adv Healthc Mater ; : e2100975, 2021 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-34263555

RESUMO

Wound healing, one of the most complex processes in the human body, involves the spatial and temporal synchronization of a variety of cell types with distinct roles. Slow or nonhealing skin wounds have potentially life-threatening consequences, ranging from infection to scar, clot, and hemorrhage. Recently, the advent of triboelectric nanogenerators (TENGs) has brought about a plethora of self-powered wound healing opportunities, owing to their pertinent features, including wide range choices of constitutive biocompatible materials, simple fabrication, portable size, high output power, and low cost. Herein, a comprehensive review of TENGs as an emerging biotechnology for wound healing applications is presented and covered from three unique aspects: electrical stimulation, antibacterial activity, and drug delivery. To provide a broader context of TENGs applicable to wound healing applications, state-of-the-art designs are presented and discussed in each section. Although some challenges remain, TENGs are proving to be a promising platform for human-centric therapeutics in the era of Internet of Things. Consequently, TENGs for wound healing are expected to provide a new solution in wound management and play an essential role in the future of point-of-care interventions.

17.
Am J Chin Med ; : 1-19, 2021 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-34263719

RESUMO

Gut microbiota has been proven to play an important role in many metabolic diseases and cardiovascular disease, particularly atherosclerosis. Ophiopogonin D (OPD), one of the effective compounds in Ophiopogon japonicus, is considered beneficial to metabolic syndrome and cardiovascular diseases. In this study, we have illuminated the effect of OPD in ApoE knockout (ApoE[Formula: see text] mice on the development of atherosclerosis and gut microbiota. To investigate the potential ability of OPD to alleviate atherosclerosis, 24 eight-week-old male ApoE[Formula: see text] mice (C57BL/6 background) were fed a high-fat diet (HFD) for 12 weeks, and 8 male C57BL/6 mice were fed a normal diet, serving as the control group. ApoE[Formula: see text] mice were randomly divided into the model group, OPD group, and simvastatin group ([Formula: see text]= 8). After treatment for 12 consecutive weeks, the results showed that OPD treatment significantly decreased the plaque formation and levels of serum lipid compared with those in the model group. In addition, OPD improved oral glucose tolerance and insulin resistance as well as reducing hepatocyte steatosis. Further analysis revealed that OPD might attenuate atherosclerosis through inhibiting mTOR phosphorylation and the consequent lipid metabolism signaling pathways mediated by SREBP1 and SCD1 in vivo and in vitro. Furthermore, OPD treatment led to significant structural changes in gut microbiota and fecal metabolites in HFD-fed mice and reduced the relative abundance of Erysipelotrichaceae genera associated with cholesterol metabolism. Collectively, these findings illustrate that OPD could significantly protect against atherosclerosis, which might be associated with the moderation of lipid metabolism and alterations in gut microbiota composition and fecal metabolites.

18.
Small ; : e2101058, 2021 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-34242471

RESUMO

The sodium-ion battery (SIB) has attracted ever growing attention as a promising alternative of the lithium-ion battery (LIB). Constructing appropriate anode materials is critical for speeding up the application of SIB. This review aims at guiding anode design from the material's perspective, and specifically focusing on solid solution metal chalcogenide anode. The sodium ion storage mechanisms of a solid solution metal chalcogenide anode is overviewed on basis of the elements it is composed of, and discusses how the solid solution character alters the electrochemical performances through diffusion and surface-controlled processes. In addition, by classifying solid solution metal chalcogenide as cation and anion, their recent applications are updated, and understanding the roles of guest elements in improving the electrochemical behaviors of a solid solution metal chalcogenide is carried out. After that, discussion of possible strategies to further optimize these anode materials in the future, flowing from crystal structure design to morphology control and finally to the intimacy improvement between conductive matrix and solid solution metal chalcogenide are also provided.

19.
Rev Sci Instrum ; 92(4): 043544, 2021 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-34243392

RESUMO

The x-ray imaging crystal spectrometer (XICS) is proposed as the principal method of diagnostics for plasma ion temperature and rotation for the China Fusion Engineering Test Reactor (CFETR) for its simplicity in implementation and no reliance on neutral beams. For D-T experiments with the electron temperature as high as 35-40 keV at the core region, highly charged high-Z ions can serve as the diagnostic ions for the XICS. For the CFETR, Xe44+, Xe51+, and W64+ are selected as the impurity ions. Appropriate crystal parameters are selected, as well as the preliminary layout for the spectrometer. We estimated the general performance of the spectrometer, including the emissivity of the impurities, the spatial resolution of the x-ray detector, and the expected count rate of line emissions. For the application in the fusion reactor environment, the effect of neutron irradiation on the crystal is briefly discussed.

20.
Rev Sci Instrum ; 92(4): 045103, 2021 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-34243417

RESUMO

A coil system to generate a uniform field is urgently needed in quantum experiments. However, general coil configurations based on the analytical method have not considered practical restrictions, such as the region for coil placement due to holes in the center of the magnetic shield, which could not be directly applied in most of the quantum experiments. In this paper, we develop a coil design method for quantum experiments using hybrid machine learning. The algorithm part consists of a machine learner based on an artificial neural network and a differential evolution (DE) learner. The cooperation of both learners demonstrates its higher efficiency than a single DE learner and robustness in the coil optimization problem compared with analytical proposals. With the help of a DE learner, in numerical simulation, a machine learner can successfully design coaxial coil systems that generate fields whose relative inhomogeneity in a 25 mm-long central region is ∼10-6 under constraints. In addition, for experiments, a coil system with 0.069% inhomogeneity of the field, designed by a machine learner, is constructed, which is mainly limited by machining the precision of the circuit board. Benefitting from machine learning's high-dimension optimization capabilities, our coil design method is convenient and has potential for various quantum experiments.

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