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In this work, N-doped and oxygen vacancy-rich NiCo2O4/NiO/Co3O4composites are synthesized by the direct calcination method. Noticeably, by changing the additive concentrations of urea dissolved in DMF (N-N dimethylformamide), the electromagnetic wave (EMW) absorption abilities of NiCo2O4/NiO/Co3O4composite effectively. A maximum reflection loss (RLmax) value at 12.94 GHz for a 2.8 mm thick sheet is -29.76 dB, while its effective absorption bandwidth (RL < -10 dB) reaches 4.21 GHz. In-depth research of possible mechanisms of EMW absorption enhancement. Owing to its simple preparation method and superb EMW absorption properties, the NiCo2O4/NiO/Co3O4composites have a chance to be suitable candidates for high-property EMW absorbers.
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OBJECTIVE: The aim of the work described here was to evaluate the diagnostic performance of a new integrated strategy using breast ultrasound (US) combined with magnetic resonance imaging (MRI) to differentiate benign and malignant breast non-mass-like lesions (NMLs) detected on US. METHODS: From October 2017 to January 2021, 183 NMLs detected on US that had undergone MRI examinations were included in this respective study. Pathological results were used as the reference standard. The integrated diagnostic strategy of breast US combined with MRI based on a combination of MRI Breast Imaging Reporting and Data System (BI-RADS) with discriminant sonographic indicators highly associated with malignancy was established and validated in a cohort of 61 women. The diagnostic performances of US, MRI and the combined method were calculated and compared. RESULTS: In the training set, the area under the receiver operating characteristic curve (AUC), sensitivity and specificity of US, MRI and the integrated diagnostic strategy using US combined with MRI for NMLs were 0.730, 93.7% and 52.3%; 0.849, 94.7% and 75.0%; and 0.901, 92.6% and 87.5%, respectively. Compared with US or MRI alone, the integrated diagnostic strategy significantly increased the AUC (p < 0.001, p = 0.007) and specificity (p < 0.001, p = 0.034) while maintaining high sensitivity (p = 0.774, p = 0.551). In the validation set, the integrated strategy of US combined with MRI (AUC = 0.899) also had good performance compared with US (AUC = 0.728) or MRI (AUC = 0.838). CONCLUSION: The integrated diagnostic strategy of US combined with MRI exhibited good performance for breast NMLs compared with either modality used alone, which can improve the diagnostic specificity while maintaining high sensitivity.
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Neoplasias de la Mama , Ultrasonografía Mamaria , Femenino , Humanos , Ultrasonografía Mamaria/métodos , Ultrasonografía , Mama/diagnóstico por imagen , Sensibilidad y Especificidad , Imagen por Resonancia Magnética/métodos , Neoplasias de la Mama/diagnóstico por imagen , Estudios RetrospectivosRESUMEN
Background: The proteomic differences between mass-like (ML) breast lesions and non-mass-like (NML) breast lesions were compared to explore the formation mechanism of NML ultrasonic morphological characteristics. Methods: From January to August 2021, tissue samples were collected from 10 patients with malignant ML (MML), 10 patients with malignant NML (MNML), 10 patients with benign ML (BML), and seven patients with benign NML (BNML). The proteomic differences between the BML and BNML groups and the MML and MNML groups were compared by data-independent acquisition (DIA) quantitative mass spectrometry. The differentially expressed proteins were analyzed by Gene Ontology (GO), Kyoto Encyclopedia of Genes and Genomes (KEGG), and protein-protein interaction (PPI) networks analyses. Results: We identified a total of 623 significantly differentially expressed proteins in the MML/MNML group, and 167 significantly differentially expressed proteins in the BML/BNML group, with relative ratios >1.2 or <-0.83. The up-regulated differential proteins were more abundant in the tumor necrosis factor (TNF) signaling pathway in both the MML/MNML and BML/BNML groups, suggesting that the TNF signaling pathway may be related to the ultrasonic morphological characteristics of breast lesions. Dual specificity mitogen-activated protein kinase 3 (MP2K3), a protein factor in the TNF signaling pathway, exhibited significant upregulation in both the malignant and BML groups. Conclusions: The TNF signaling pathway may be associated with the ultrasonic morphological characteristics of breast lesions. MP2K3 is the up-regulated differential expression protein in the MML/MNML and BML/BNML groups, which may be related to the ultrasonic morphological characteristics of breast lesions.
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Finding solutions to the challenges posed by China's urbanization is an urgent, pressing global concern. An effective approach for evaluating the ecological well-being performance (EWP) is a guideline for improvement. Most previous studies have focused on the evaluation of EWP efficiency without considering the effectiveness of the EWP, which may mislead the practice of improving the EWP. This paper proposed a bi-dimensional effectiveness and efficiency perspective evaluation of the EWP for pursuing sustainable development goals. The Ecological Consumption Index and the Human Development Index are selected to evaluate indicators for the EWP. The entropy method, line-weighted method, and four-quadrant evaluation framework are used to disclose EWP effectiveness. A Super SBM model and the DEA moving split-windows analysis method are applied to calculate the EWP efficiency. Data from 30 provinces in China for the period of 1997 to 2019 have been collected for empirical study to demonstrate the effectiveness of the proposed method. The main findings of the case study are: (1) The ECI and HDI increased during the study period, while the annual average value of the EWP efficiency among 30 provinces in China has decreased with fluctuation; (2) provinces in southern China and Chongqing have a low level of ECI and demonstrate good performance in the HDI; and (3) most developed regions, such as Beijing, Shanghai, and Guangdong, have not presented the best EWPs. The results of this study can provide a basis for understanding the EWP in China so as to formulate targeted sustainable-development strategies.
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Desarrollo Económico , Urbanización , Humanos , China , Beijing , Desarrollo Sostenible , EficienciaRESUMEN
Background: Previous studies show the size of lesions could affect the diagnostic accuracy of contrast-enhanced ultrasound (CEUS). It is unclear whether CEUS has good diagnostic performance for lesions ≤2.0 and ≤1.0 cm. It is beneficial for the early diagnosis to explore the application of CEUS in breast lesions of different sizes. This study aims to analyze the diagnostic performance of CEUS and explore diagnostic models better suited to breast lesions of different sizes. Methods: A total of 1,059 lesions (656 benign and 403 malignant) examined by ultrasound and CEUS with definite pathological results were included in this retrospective study and divided into training (n=847) and validation (n=212) sets. All lesions were divided into three groups according to size. Diagnostic models (M0: all lesions; M1: ≤1.0 cm, M2: >1.0-2.0 cm, and M3: >2.0 cm) were developed through logistic regression analyses of CEUS features from the training set. Diagnostic performance was evaluated using the area under the receiver operating characteristic curve (AUC) and validated in the validation set. Results: The median age of patients was 45±11 years (range, 18-80 years). The AUC values of M0 combined with the Breast Imaging Reporting and Data System (BI-RADS) in the training and validation sets were 0.921 and 0.922, respectively (P=0.893). The AUC values of M0 combined with BI-RADS in the three groups were 0.844, 0.936 and 0.928 respectively. M0 was less effective in diagnosing lesions ≤1.0 cm (0.844 vs. 0.921, P=0.029). The AUC of M1 combined with BI-RADS for lesions ≤1.0 cm was higher than that of M0 (0.893 vs. 0.844, P=0.047), and M2 and M3 had no statistical difference in diagnostic performance when compared with M0 (P=0.243; P=0.246). Conclusions: The diagnostic performance of CEUS was closely related to lesion size. Establishing a new diagnostic model for lesions ≤1.0 cm can improve the CEUS diagnostic performance for breast lesions ≤1.0 cm.
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OBJECTIVES: To investigate the prevalence of diabetes mellitus (DM) among Uygur children in Hotan Prefecture of Xinjiang, China, as well as the factors influencing the development of DM. METHODS: The cluster random sampling method was used to select 5 308 children, aged 4-18 years, from the middle and primary schools and kindergartens in Hotan Prefecture of Xinjiang. The survey methods included questionnaire survey and the measurement of height and weight. All subjects were tested for fasting fingertip blood glucose to investigate the prevalence of DM and impaired fasting glucose (IFG). RESULTS: A total of 5 184 valid questionnaires were collected. Fourteen children (0.27%) were found to have DM, among whom 8 had type 1 DM, 2 had type 2 DM, and 4 had unclassified DM. Twenty-nine children (0.56%) were found to have IFG. There was no significant difference in the prevalence rate of DM and IFG between boys and girls (P>0.05). The prevalence rate of DM was 0.18% in the 4-<10 years group, 0.47% in the 10-<15 years group, and 0.07% in the 15-18 years group (P=0.072).The prevalence rate of IFG in the above three age groups was 0.18%, 0.94%, and 0.42%, respectively, with a significant difference among groups (P=0.007). The proportion of family history of DM and the proportion of overweight/obesity in children with DM were significantly higher than those in children without DM (P<0.05), while the proportion of children with DM who preferred coarse grains was significantly lower than that in children without DM (P<0.05). CONCLUSIONS: The prevalence of DM and IFG in Uyghur children in Hotan Prefecture of Xinjiang is relatively low. There is no significant difference in the prevalence of DM among children of different genders or age groups, but the prevalence of IFG in children of different age groups is different. A family history of DM, overweight or obesity, and low intake of coarse grains might be associated with the development of DM.
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Obesidad Infantil , Estado Prediabético , Adolescente , Glucemia , Niño , Preescolar , China/epidemiología , Femenino , Humanos , Masculino , Estado Prediabético/epidemiología , Prevalencia , Factores de RiesgoRESUMEN
The van der Waals layered material CuInP2S6 features interesting functional behavior, including the existence of four uniaxial polarization states, polarization reversal against the electric field through Cu ion migration, a negative-capacitance regime, and reversible extraction of Cu ions. At the heart of these characteristics lies the high mobility of Cu ions, which also determines the spontaneous polarization. Therefore, Cu migration across the lattice results in unusual ferroelectric behavior. Here, we demonstrate how the interplay of polar and ionic properties provides a path to ionically controlled ferroelectric behavior, achieved by applying selected DC voltage pulses and subsequently probing ferroelectric switching during fast triangular voltage sweeps. Using current measurements and theoretical calculations, we observe that increasing DC pulse duration results in higher ionic currents, the buildup of an internal electric field that shifts polarization loops, and an increase in total switchable polarization by â¼50% due to the existence of a high polarization phase which is stabilized by the internal electric field. Apart from tuning ferroelectric behavior by selected square pulses, hysteretic polarization switching can even be entirely deactivated and reactivated, resulting in three-state systems where polarization switching is either inhibited or can be performed in two different directions.
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Fe-N-C materials exhibit excellent activity and stability for oxygen reduction reaction (ORR), as one of the most promising candidates to replace commercial Pt/C catalysts. However, it is challenging to unravel features of the superior ORR activity originating from Fe-N-C materials. In this work, the electronic and geometric structures of the isolated Fe-N-C sites and their correlations with the ORR performance are investigated by varying the secondary thermal activation temperature of a rationally designed NC-supported Fe single-atom catalyst (SAC). The systematic analyses demonstrate the significant role of coordinated atoms of SA and metallic Fe nanoparticles (NPs) in altering the electronic structure of isolated Fe-N-C sites. Meanwhile, strong interaction between isolated Fe-N-C sites and adjacent Fe NPs can change the geometric structure of isolated Fe-N-C sites. Theoretical calculations reveal that optimal regulation of the electronic and geometric structure of isolated Fe-N-C sites by the co-existence of Fe NPs narrows the energy barriers of the rate-limiting steps of ORR, resulting in outstanding ORR performance. This work not only provides the fundamental understanding of the underlying structure-activity relationship, but also sheds light on designing efficient Fe-N-C catalysts.
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Recently, novel core-shell MOF@COF hybrids display excellent performance in various fields because of their inherited advantages from their parent MOFs and/or COFs. However, it is still a grand challenge to adjust the morphology of MOFs and/or COFs for consequent performance improvement. Herein, a Ti-MOF@TpTt hybrid coated with ultra-thin COF nanobelt, which is different from the fibrillar-like parent COF, is successfully synthesized through a sequential growth strategy. The as-obtained Pd decorated Ti-MOF@TpTt catalyst exhibits much higher photocatalytic performance than those of Ti-MOF, TpTt-COF, and Ti-MOF@TpTt hybrids with fibrillar-like COF shell for the photocatalytic cascade reactions of ammonia borane (AB) hydrolysis and nitroarenes hydrogenation. These can be attributed to its high BET surface area, core-shell structure, and type II heterojunction, which offers more accessible active sites and improves the separation efficiency of photo-generated carriers. Finally, the possible mechanisms of the cascade reaction are also proposed to well explain the improved performance of this photocatalytic system. This work presents a constructive route for designing core-shell MOF@COF hybrids with controllable morphology adjustment of COF shell, leading to the improved photocatalytic ability to broaden the applications of MOF/COF hybrid materials.
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A ferroelectric semiconductor junction is a promising two-terminal ferroelectric device for nonvolatile memory and neuromorphic computing applications. In this work, we propose and report the experimental demonstration of asymmetric metal/α-In2Se3/Si crossbar ferroelectric semiconductor junctions (c-FSJs). The depletion in doped Si is used to enhance the modulation of the effective Schottky barrier height through the ferroelectric polarization. A high-performance α-In2Se3 c-FSJ is achieved with a high on/off ratio > 104 at room temperature, on/off ratio > 103 at an elevated temperature of 140 °C, retention > 104 s, and endurance > 106 cycles. The on/off ratio of the α-In2Se3 asymmetric FSJs can be further enhanced to >108 by introducing a metal/α-In2Se3/insulator/metal structure.
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Articular cartilage regeneration is one of the challenges faced by orthopedic surgeons. Microcarrier applications have made great advances in cartilage tissue engineering in recent years and enable cost-effective cell expansion, thus providing permissive microenvironments for cells. In addition, microcarriers can be loaded with proteins, factors, and drugs for cartilage regeneration. Some microcarriers also have the advantages of injectability and targeted delivery. The application of microcarriers with these characteristics can overcome the limitations of traditional methods and provide additional advantages. In terms of the transformation potential, microcarriers have not only many advantages, such as providing sufficient and beneficial cells, factors, drugs, and microenvironments for cartilage regeneration, but also many application characteristics; for example, they can be injected to reduce invasiveness, transplanted after microtissue formation to increase efficiency, or combined with other stents to improve mechanical properties. Therefore, this technology has enormous potential for clinical transformation. In this review, we focus on recent advances in microcarriers for cartilage regeneration. We compare the characteristics of microcarriers with other methods for repairing cartilage defects, provide an overview of the advantages of microcarriers, discuss the potential of microcarrier systems, and present an outlook for future development. TRANSLATIONAL POTENTIAL OF THIS ARTICLE: We reviewed the advantages and recent advances of microcarriers for cartilage regeneration. This review could give many scholars a better understanding of microcarriers, which can provide doctors with potential methods for treating patients with cartilage injure.
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The geriatric nutritional risk index (GNRI) is associated with the prognosis of many diseases. However, the association between the GNRI and the prognosis of patients aged ≥65 years with severe community-acquired pneumonia (SCAP) has not been studied. We aimed to evaluate the prognostic value of GNRI in elderly SCAP patients.This study retrospectively analyzed the clinical data of 346 patients aged ≥65 years with SCAP from December 2013 to September 2019. Patients were divided into 4 groups by the GNRI. The chi-square test or student's t test was used to compare the differences between the groups. Logistic regression analysis was used to evaluate the factors that affect prognosis. The receiver operating characteristic curve was used to compare the prognostic performance of the GNRI with other indicators. A GNRI-based nomogram was established based on the result of the multivariate analysis.Two hundred nine (60.4%) patients had a poor prognosis. GNRI scores were significantly lower in the poor prognosis group than in the group with a good prognosis. In the multivariate analysis, gender, mean arterial pressure, neutrophil counts, and the GNRI were independently correlated with the prognosis of elderly patients. The GNRI was a significantly better predictor for poor prognosis than other indicators. The GNRI-based nomogram had excellent prediction capabilities.GNRI is a simple and effective prognostic indicator for elderly patients with SCAP, and a GNRI-based nomogram can aid in developing individualized treatment plans for elderly patients with SCAP.