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1.
Artigo em Inglês | MEDLINE | ID: mdl-38605498

RESUMO

Lead-free relaxor ferroelectric ceramics with outstanding energy-storage (ES) density (Wrec) and high ES efficiency (η) are crucial for advanced pulse-power capacitors. This study introduces a strategic approach to maximizing the polarization difference (ΔP) by inducing a transition from the ferroelectric phase to the ergodic relaxor (ER) phase. By employing this strategy, a series of ceramics, (1 - x)(Bi0.5Na0.4K0.1)TiO3-x(Sr0.85La0.1)(Zr0.5Ti0.5)O3 (BNKT-xSLZT), with varying SLZT content (x = 0.05, 0.10, 0.15, and 0.20), were designed. The addition of SLZT enhances cationic disorder, induces vacancies at A sites, and disrupts long-range ferroelectric order, facilitating the formation of polar nanoregions and enhancing relaxor ferroelectric behavior. Furthermore, a viscous polymer process (VPP) technology is employed to optimize the ceramics' structure, aiming to increase the breakdown strength (Eb) and enhance ΔP. Ultimately, enhanced ES performance is demonstrated in BNKT-0.15SLZTVPP, achieving a remarkable Wrec of 6.85 J/cm3 and η of 84% under 470 kV/cm. This composition demonstrates excellent stability with minimal variations in Wrec (3.0%) and η (4.4%) over the temperature range of 20-110 °C. Additionally, BNKT-0.15SLZTVPP exhibits exceptional pulse charge-discharge properties, featuring a high discharge density of 3.72 J/cm3, a large power density of 164.2 MW/cm3, and a short discharge time (t0.9) of 193 ns under 300 kV/cm. The study validates the practicality of BNKT-0.15SLZTVPP for pulse capacitors and underscores the potential to enhance ES performance through A-site donor doping and VPP technology. This work provides a comprehensive understanding of the interplay among composition, structure, and ES properties in lead-free relaxor dielectric ceramics, laying the groundwork for innovative advancements in the field.

2.
World J Psychiatry ; 14(1): 76-87, 2024 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-38327892

RESUMO

BACKGROUND: Occult breast cancer (OBC) has traditionally been considered to be a carcinoma of unknown primary origin with a favorable prognosis and can be treated as stage II-III breast cancer. Due to the small number of cases and limited clinical ex-perience, treatments vary greatly around the world and no standardized treat-ment has yet been established. AIM: To investigate the clinicopathological features, psychological status and prog-nostic features of patients with OBC. METHODS: The clinicopathological data of 33 OBC patients diagnosed and treated in the Affiliated Hospital of Xuzhou Medical University and Xuzhou Central Hospital from November 2015 to November 2022 were retrospectively analyzed. The psychological status of OBC patients was evaluated by the Self-rating Anxiety Scale and Self-rating Depression Scale. Patients' emotions, stress perception and psychological resilience were evaluated by the Positive and Negative Affect Schedule, the Chinese Perceived Stress Scale, and the Connor-Davidson Resilience Scale (CD-RISC), respectively. Patient survival was calculated using the Kaplan-Meier method, and survival curves were plotted for analysis with the log-rank test. Univariate and multivariate survival analyses were performed using the Cox regression model. RESULTS: The 33 OBC patients included 32 females and 1 male. Of the 33 patients, 30 (91%) had axillary tumors, 3 (9%) had a neck mass as the primary symptom; 18 (54.5%) had estrogen receptor-positive tumors, 17 (51.5%) had progesterone receptor-positive tumors, and 18 (54.5%) had Her-2-positive tumors; 24 (72.7%) received surgical treatment, including 18 patients who underwent modified radical mastectomy, 1 patient who underwent breast-conserving surgery plus axillary lymph node dissection (ALND), and 5 patients who underwent ALND alone; 12 patients received preoperative neoadjuvant therapy. All 30 patients developed anxiety and depression, with low positive affect scores and high negative affect scores, accompanied by a high stress level and poor psychological resilience. There were no differences in the psychological status of patients according to age, body mass index, or menopausal status. The overall survival and disease-free survival (DFS) of all the patients were 83.3% and 55.7%, respectively. Univariate analysis demonstrated that the initial tumor site (P = 0.021) and node stage (P = 0.020) were factors that may affect patient prognosis. The 5-year DFS rate of OBC patients who received radiotherapy was greater (P < 0.001), while the use of different surgical methods (P = 0.687) had no statistically significant effect on patient outcomes. Multivariate analysis revealed that radiotherapy (P = 0.031) was an independent prognostic factor. Receiving radiotherapy had a significant effect on the CD-RISC score (P = 0.02). CONCLUSION: OBC is a rare breast disease whose diagnosis and treatment are currently controversial. There was no significant difference in the efficacy of other less invasive surgical procedures compared to those of modified radical mastectomy. In addition, radiotherapy can significantly improve patient outcomes. We should pay attention to the psychological state of patients while they receive antitumor therapy.

3.
Front Immunol ; 14: 1256355, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37868990

RESUMO

Background: Numerous studies and research papers have provided evidence suggesting that tertiary lymphoid structures (TLS) play a crucial role in combating and suppressing tumor growth and progression. Despite the wealth of information on the significance of TLS in various types of cancer, their prognostic value in gastrointestinal (GI) cancers remains uncertain. Therefore, this meta-analysis investigated the prognostic value of TLS in GI cancers. Methods: We searched Web of science, Pubmed, Embase and Cochrane Library for studies that met the requirements as of May 1, 2023, and the hazard ratio (HR) and the corresponding 95% confidence interval (CI) were included in the analysis. The bioinformatics analysis results based on the TCGA database are used to supplement our research. Results: The meta-analysis included 32 studies involving 5778 patients. The results of comprehensive analysis showed that TLS-High is associated with prolonged OS (HR=0.525,95%CI:0.447-0.616 (P < 0.001), RFS (HR=0.546,95%CI:0.461-0.647, P < 0.001), DFS (HR=0.519,95%CI:0.417-0.646, P < 0.001) and PFS (HR=0.588,95%CI:0.406-0.852, P=0.005) in GI cancer. Among the patients who received immunotherapy, TLS-High is associated with significantly prolonged OS (HR=0.475, 95%CI:0.282-0.799, P=0.005) and PFS(HR=0.576, 95%CI:0.381-0.871, P=0.009). It is worth noting that subgroup analysis showed that there was no significant relationship between TLS and OS(HR=0.775, 95%CI:0.570-1.053,P=0.103) in CRC. And when Present is used as the cut-off criteria of TLS, there is no significant correlation between TLS and OS (HR=0.850, 95%CI:0.721-1.002, P=0.053)in HCC. Conclusion: TLS is a significant predictor of the prognosis of GI cancers and has the potential to become a prognostic biomarker of immunotherapy-related patients. Systematic review registration: https://www.crd.york.ac.uk/PROSPERO/#recordDetails, identifier CRD42023443562.


Assuntos
Carcinoma Hepatocelular , Neoplasias Gastrointestinais , Neoplasias Hepáticas , Estruturas Linfoides Terciárias , Humanos , Prognóstico , Biomarcadores Tumorais
4.
Pest Manag Sci ; 79(8): 2675-2685, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-36889932

RESUMO

BACKGROUND: The rational utilization of botanical secondary metabolites is one of the strategies to reduce the application of chemical fungicides. The extensive biological activities of Clausena lansium indicate that it has the potential to develop botanical fungicides. RESULTS: A systematic investigation on the antifungal alkaloids from C. lansium branch-leaves following bioassay-guided isolation was implemented. Sixteen alkaloids, including two new and nine known carbazole alkaloids, one known quinoline alkaloid and four known amides, were isolated. Compounds 4, 7, 12 and 14 showed strong antifungal activity on Phytophthora capsiciwith EC50 values ranging from 50.67 to 70.82 µg mL-1 . Compounds 1, 3, 8, 10, 11, 12 and 16 displayed different degrees of antifungal activity against Botryosphaeria dothidea with EC50 values ranging from 54.18 to 129.83 µg mL-1 . It was reported for the first time that these alkaloids had antifungal effects on P. capsici or B. dothidea, and their structure-activity relationships were further discussed systematically. Additionally, among all alkaloids, dictamine (12) had the strongest antifungal activities against P. capsici (EC50  = 50.67 µg mL-1 ) and B. dothidea (EC50  = 54.18 µg mL-1 ), and its physiological effects on P. capsici and B. dothidea also were further evaluated. CONCLUSION: Capsicum lansium is a potential source of antifungal alkaloids, and C. lansium alkaloids had the potential as lead compounds of botanical fungicides in the development of new fungicides with novel action mechanism. © 2023 Society of Chemical Industry.


Assuntos
Alcaloides , Clausena , Fungicidas Industriais , Rutaceae , Clausena/química , Antifúngicos/farmacologia , Estrutura Molecular , Fungicidas Industriais/farmacologia , Fungicidas Industriais/análise , Alcaloides/farmacologia , Alcaloides/química , Folhas de Planta/química
5.
ACS Appl Mater Interfaces ; 15(5): 6990-7001, 2023 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-36694407

RESUMO

Although relaxor ferroelectrics have been widely investigated owing to their various advantages, there are still impediments to boosting their energy-storage density (Wrec) and energy-storage efficiency (η). In this paper, we propose a cooperative optimization strategy for achieving comprehensive outstanding energy-storage performance in (Na0.5Bi0.5)0.7Sr0.3TiO3 (NBST)-based ceramics by triggering a nonergodic-to-ergodic transformation and optimizing the forming process. The first step of substituting NaNbO3 (NN) for NBST generated an ergodic state and induced polar nanoregions under the guidance of a phase-field simulation. The second step was to apply a viscous polymer process (VPP) to the 0.85NBST-0.15NN ceramics, which reduced porosity and increased compactness, resulting in a significant polarization difference and high breakdown strength. Consequently, 0.85NBST-0.15NN-VPP ceramics optimized by this cooperative two-step strategy possessed improved energy-storage characteristics (Wrec = 7.6 J/cm3, η = 90%) under 410 kV/cm as well as reliable temperature adaptability within a range of 20-120 °C, outperforming most reported (Na0.5Bi0.5) TiO3-based ceramics. The improved energy-storage performance validates the developed ceramics' practical applicability as well as the advantages of implementing a cooperative optimization technique to fabricate similar high-performance dielectric ceramics.

6.
Pest Manag Sci ; 77(3): 1355-1360, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33089666

RESUMO

BACKGROUND: Clausena lansium (Lour.) Skeels, belonging to the genus Clausena of the family Rutaceae, has a wide range of medical and agricultural activities. Previous studies on agricultural activities have shown that C. lansium extracts and some components have obvious herbicidal activities. In order to study systematically herbicidal activity of this plant, we studied the herbicidal effect of ethyl acetate (EtOAc) extract from the stems and leaves of this plant and further isolated the active compounds. RESULTS: The EtOAc extract inhibited the growth of roots and shoots of Echinochloa crus-galli (L.) Beauv., and the inhibitory effect of the EtOAc extract on roots were stronger than those on shoots with half maximal inhibitory concentration (IC50 ) values of 420.45 and 585.05 mg L-1 , respectively. Fifteen compounds were subsequently isolated and identified from the stems and leaves of C. lansium, including nine O-monoterpenoid furanocoumarins and six cinnamamides. Our results showed that most compounds exhibited varying degrees of herbicidal activities to E. crus-galli. Among them, compounds 3, 8, and 13-15 showed the best inhibitory activities on the growth of E. crus-galli roots, with inhibition rate values ranging from 70% to 83% at a concentration of 300 mg L-1 . Compounds 1 and 2 are two new compounds, and their structures were established as 5-O-monoterpenoid furanocoumarin and 8-O-monoterpenoid furanocoumarin, and named as claulansicoumarin-A and -B, respectively. CONCLUSION: The EtOAc extract and pure compounds showed noticeable herbicidal activities against E. crus-galli and indicated a great potential for these natural compounds to be developed as a herbicide. © 2020 Society of Chemical Industry.


Assuntos
Clausena , Furocumarinas , Herbicidas , Herbicidas/farmacologia , Monoterpenos , Folhas de Planta
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