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1.
Nat Commun ; 14(1): 7647, 2023 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-37996440

RESUMO

The interplay between topology and interaction always plays an important role in condensed matter physics and induces many exotic quantum phases, while rare transition metal layered material (TMLM) has been proved to possess both. Here we report a TMLM Ta2Pd3Te5 has the two-dimensional second-order topology (also a quadrupole topological insulator) with correlated edge states - Luttinger liquid. It is ascribed to the unconventional nature of the mismatch between charge- and atomic- centers induced by a remarkable double-band inversion. This one-dimensional protected edge state preserves the Luttinger liquid behavior with robustness and universality in scale from micro- to macro- size, leading to a significant anisotropic electrical transport through two-dimensional sides of bulk materials. Moreover, the bulk gap can be modulated by the thickness, resulting in an extensive-range phase diagram for Luttinger liquid. These provide an attractive model to study the interaction and quantum phases in correlated topological systems.

2.
Front Psychol ; 14: 1283781, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37794907

RESUMO

With the development of educational cognitive neuroscience, language instruction is no longer perceived as mechanical teaching and learning. Individual cognitive proficiency has been found to play a crucial role in language acquisition, particularly in the realm of reading comprehension. The primary objective of this study was to investigate two key aspects: firstly, to assess the predictive effects of the central executive (CE) on the Chinese reading comprehension scores of Chinese primary school students, and secondly, to explore the influence of CE training on the Chinese reading comprehension performance of Chinese primary school students. Chinese primary school students were recruited as participants. Experiment 1 used a Chinese N-back task, a Chinese Stroop task, and a number-pinyin conversion task to investigate the predictive effect of the CE components on Chinese reading comprehension. Experiment 2, based on the results of Experiment 1, used the Chinese character N-back training to explore the influence of updating training on Chinese reading comprehension. The findings from Experiment 1 underscored that CE had a predictive effect on Chinese reading comprehension scores. And updating had a prominent role in it. Experiment 2 revealed that the experimental group exhibited an enhancement in their updating performance following N-back training. Although the reading comprehension performance of the two groups after training did not produce significant differences in total scores, the experimental group showed maintained and higher microscopic reading comprehension scores than the control group in the more difficult post-test. In summary, this study yields two primary conclusions: (1) CE was able to predict Chinese reading comprehension scores. Updating has an important role in prediction. (2) Updating training enhances students' updating performance and positively influences students' Chinese microscopic reading comprehension performance.

3.
Shock ; 60(4): 594-602, 2023 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-37646610

RESUMO

ABSTRACT: Gut barrier dysfunction caused by intestinal ischemia/reperfusion (I/R) injury is associated with substantial death and morbidity. In this research, the role of microRNAs (miRNAs) in regulating intestinal I/R injury was investigated. We used miRNA sequencing to analyze clinical ischemic and normal intestinal samples. Through bioinformatics analysis based on sequencing results, we found that upregulated miRNAs inhibited epithelial barrier function and cell proliferation, with miR-379-5p being the most significantly upregulated in the ischemic intestine. Further studies confirmed the role of miR-379-5p through experiments in the human ischemic intestine, the mouse I/R injury model in vivo , and cell hypoxia/reoxygenation models in vitro . Inhibiting miR-379-5p increased epithelial cell proliferation and improved barrier function after I/R injury. We also identified eukaryotic translation initiation factor 4 gamma 2 (EIF4G2) as a downstream target gene of miR-379-5p through bioinformatics prediction and experimental verification. The findings suggest that inhibiting miR-379-5p could improve intestinal epithelial cell proliferation and barrier function by targeting EIF4G2. The goal of this study was to find a potential target for treating I/R injury in the intestine, as well as to prevent and mitigate the damage caused.


Assuntos
MicroRNAs , Traumatismo por Reperfusão , Animais , Humanos , Camundongos , Apoptose , Proliferação de Células/genética , Modelos Animais de Doenças , Fator de Iniciação 4G em Eucariotos , Isquemia , MicroRNAs/genética , Recuperação de Função Fisiológica , Reperfusão , Traumatismo por Reperfusão/genética
4.
Pharm Biol ; 61(1): 1310-1317, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37621064

RESUMO

CONTEXT: (-)-Epigallocatechin-3-gallate (EGCG) is involved in cell proliferation and ischemia/reperfusion (I/R) injury of several organs. OBJECTIVE: To identify the role of EGCG in intestinal epithelial proliferation and barrier exposed to I/R injury. MATERIAL AND METHODS: Fifty Sprague-Dawley rats were divided into sham, I/R, I/R + EGCG (12.5 mg/kg), I/R + EGCG (25 mg/kg) and I/R + EGCG (50 mg/kg). I/R group rats were subjected to intestinal ischemia for 1 h and 6 h reperfusion. The rats were supplemented with EGCG 12.5, 25 and 50 mg/kg daily for 3 days via intraperitoneal injection before surgery. We used IEC-6 to expose to hypoxia/reoxygenation (H/R) injury to mimic I/R in vivo. IEC-6 cells were divided into control, H/R and H/R + EGCG (40 µmol/L). The effects of EGCG and its mechanism was explored. RESULTS: Pharmacological treatment with EGCG notably improves intestinal epithelial proliferation (12.5 mg/kg, 1.74-fold; 25 mg/kg, 2.93-fold, and 50 mg/kg, 4.33-fold) and barrier function after I/R injury. EGCG promoted cell proliferation (2.99-fold) and increased the expression of occludin (2.36-fold) and ZO-1 (1.64-fold) in IEC-6 cells after H/R injury. EGCG promoted proliferation of IEC-6 cells with ED50 values of 18.16 µmol/L. Further investigations indicated that EGCG activated Nurr1 expression in intestine after I/R injury. EGCG promote cell proliferation and increased the expression of occludin and ZO-1 in IEC-6 cells after H/R injury were abrogated in the knockdown of Nurr1 by siRNA. DISCUSSION AND CONCLUSION: Our findings indicate that EGCG promotes intestinal epithelial cell proliferation and barrier function after I/R injury in vitro and in vivo via activation of Nurr1.


Assuntos
Membro 2 do Grupo A da Subfamília 4 de Receptores Nucleares , Traumatismo por Reperfusão , Animais , Ratos , Proliferação de Células , Intestinos , Isquemia , Ocludina , Ratos Sprague-Dawley , Traumatismo por Reperfusão/tratamento farmacológico , Membro 2 do Grupo A da Subfamília 4 de Receptores Nucleares/metabolismo
5.
Front Psychol ; 14: 1163132, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37287774

RESUMO

Objective: This study aimed to explore the effects of working memory updating training on primary school students' writing ability and performance. Methods: A total of 46 fourth-grade Chinese primary school students were recruited; their performance in the Chinese character N-back training task, the Writing Ability Questionnaire, and a time-limited writing task was assessed. Results: The paired-sample t-test revealed that working memory updating training significantly improved the experimental group's working memory level. After training, a repeated measures ANOVA revealed that the experimental group's performance on the Writing Ability Questionnaire improved and was higher than that of the control group. In the time-limited writing task, independent-sample t-tests revealed that the experimental group's writing fluency increased and was higher than that of the control group, while the latter's grammatical accuracy and complexity decreased and were lower than those of the former. Conclusion: Working memory updating training can be used as auxiliary cognitive training to improve primary school students' working memory level, thereby promoting their writing development.

6.
Environ Sci Technol ; 57(18): 7174-7184, 2023 05 09.
Artigo em Inglês | MEDLINE | ID: mdl-37079659

RESUMO

Desert carbon sequestration plays an active role in promoting carbon neutralization. However, the current understanding of the effect of hydrothermal interactions and soil properties on desert carbon sequestration after precipitation remains unclear. Based on the experiment in the hinterland of the Taklimakan Desert, we found that the heavy precipitation will accelerate the weakening of abiotic carbon sequestration in deserts under the background of global warming and intensified water cycle. The high soil moisture can significantly stimulate sand to release CO2 at an incredible speed by rapidly increasing microbial activity and organic matter diffusion. At this time, the CO2 flux in the shifting sand was synergistically affected by soil temperature and soil moisture. As far as soil properties are concerned, with less organic carbon substrate and stronger soil alkalinity, the carbon sequestration of shifting sand is gradually highlighted and strengthened at low temperature. On the contrary, the carbon sequestration of shifting sand is gradually weakened. Our study provides a new way to assess the contribution of desert to the global carbon cycle and improve the accuracy and scope of application.


Assuntos
Sequestro de Carbono , Ecossistema , Clima Desértico , Dióxido de Carbono , Solo/química , Carbono , China
7.
Innovation (Camb) ; 4(2): 100399, 2023 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-36923023

RESUMO

The modulation of topological electronic state by an external magnetic field is highly desired for condensed-matter physics. Schemes to achieve this have been proposed theoretically, but few can be realized experimentally. Here, combining transverse transport, theoretical calculations, and scanning tunneling microscopy/spectroscopy (STM/S) investigations, we provide an observation that the topological electronic state, accompanied by an emergent magneto-transport phenomenon, was modulated by applying magnetic field through induced non-collinear magnetism in the magnetic Weyl semimetal EuB6. A giant unconventional anomalous Hall effect (UAHE) is found during the magnetization re-orientation from easy axes to hard ones in magnetic field, with a UAHE peak around the low field of 5 kOe. Under the reasonable spin-canting effect, the folding of the topological anti-crossing bands occurs, generating a strong Berry curvature that accounts for the observed UAHE. Field-dependent STM/S reveals a highly synchronous evolution of electronic density of states, with a dI/dV peak around the same field of 5 kOe, which provides evidence to the folded bands and excited UAHE by external magnetic fields. This finding elucidates the connection between the real-space non-collinear magnetism and the k-space topological electronic state and establishes a novel manner to engineer the magneto-transport behaviors of correlated electrons for future topological spintronics.

8.
Heliyon ; 9(3): e14147, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36923875

RESUMO

As a special geographical unit on the earth, deserts have certain differences in planetary boundary layer (PBL) characteristics from other surface types. In order to find out the long-term evolution law of the Gurbantünggüt Desert, on the basis of evaluating the availability of reanalysis data, using the most effective reanalysis data and situ measured data in this area, the evolution law of the atmospheric boundary layer in the desert area was studied. The results show that among the ERA5, MERRA2, JRA-55 and NCEP-FNL reanalysis data, the ERA5 data has the smallest error with the measured data in the comparison of ground elements or high-altitude meteorology parameters, and can be used for the long-term evolution of the atmospheric boundary layer in desert areas. Based on the ERA5 dataset, the annual planetary boundary layer height (PBLH) of the desert fluctuated between 1979 and 1985, but showed a downward trend overall. From 1986 to 2019, the PBLH generally shows an upward trend, and by 2020, the PBLH decreases again. The PBLH in the summer of the desert was contrary to the inter-annual change trend of the PBLH throughout the year. The spatial distribution shows that the PBLH has the characteristics of north-south anisotropy. The characteristics of the ABL in the Gurbantünggüt Desert in different thermal states in summer vary greatly. Based on the sounding observational data, the average PBLH of the stable boundary layer in the Gurbantünggüt Desert in summer is 496 m, the average PBLH of the convective boundary layer is 1693 m, and the average PBLH of the neutral boundary layer is 1208 m. The ABL in desert areas from 02:00 to 08:00 and 23:00 is dominated by stable boundary layers, of which the proportion of stable boundary layers at 05:00 is as high as 67%. During the day, the boundary layer from 14:00 to 17:00 is mainly the convective boundary layer, accounting for more than 50%, and the boundary layer at 20:00 is mainly a neutral boundary layer, accounting for 55%.

9.
Sci Bull (Beijing) ; 67(6): 598-608, 2022 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-36546121

RESUMO

The complete band representations (BRs) have been constructed in the work of topological quantum chemistry. Each BR is expressed by either a localized orbital at a Wyckoff site in real space, or by a set of irreducible representations in momentum space. In this work, we define unconventional materials with a common feature of the mismatch between average electronic centers and atomic positions. They can be effectively diagnosed as whose occupied bands can be expressed as a sum of elementary BRs (eBRs), but not a sum of atomic-orbital-induced BRs (aBRs). The existence of an essential BR at an empty site is described by nonzero real-space invariants (RSIs). The "valence" states can be derived by the aBR decomposition, and unconventional materials are supposed to have an uncompensated total "valence" state. The high-throughput screening for unconventional materials has been performed through the first-principles calculations. We have discovered 423 unconventional compounds, including thermoelectronic materials, higher-order topological insulators, electrides, hydrogen storage materials, hydrogen evolution reaction electrocatalysts, electrodes, and superconductors. The diversity of these interesting properties and applications would be widely studied in the future.

10.
Sci Rep ; 12(1): 16786, 2022 10 06.
Artigo em Inglês | MEDLINE | ID: mdl-36202905

RESUMO

The association between the expression of Lysyl oxidase (LOX) and its clinicopathological parameters and prognosis in patients with gastric cancer (GC) is still disputed. We performed this meta-analysis and bioinformatics analysis to clarify the relationship between the expression and methylation level of LOX with its clinicopathological parameters and prognostic value. We applied odds ratios with a 95% confidence interval to study the associations between LOX expression and clinicopathological parameters and overall survival (OS) in GC patients. In addition, association analysis of promoter methylation levels and expression of LOX with its prognostic value was performed using the Cancer Genome Atlas (TCGA) and four Gene Expression Omnibus (GEO) datasets. The PRISMA 2020 checklist was used to guide the data extraction and analysis. This meta-analysis includes seven clinical studies with a total of 1435 GC patients. LOX expression was related to lymph node metastasis and tumor distant metastasis in GC patients, but not to gender, tumor differentiation, Lauren classification, or tumor depth of invasion. Patients with GC grouped in high-expression of LOX had a much worse OS than those in low-expression. In addition, TCGA and four GEO datasets with 1279 samples were included in the bioinformatics analysis. The bioinformatics analysis showed that patients with high LOX levels had poor OS; low levels of methylation at some cg sites in the LOX gene were strongly related to poor OS and PFS; and methylation levels of LOX are negatively correlated with advanced tumor stage. The conclusion from comprehensive DNA methylation and gene expression analysis supports LOX as a specific diagnostic and prognosis biomarker in GC. LOX expression was related to lymph node metastasis, tumor distant metastasis and poor prognosis in GC. Low methylation levels were related to advanced tumor stage and poor prognosis in GC. Integrative analysis supports LOX as a specific diagnostic and prognosis biomarker in GC.


Assuntos
Neoplasias Gástricas , Biomarcadores , Biomarcadores Tumorais/metabolismo , Biologia Computacional , Humanos , Metástase Linfática , Prognóstico , Proteína-Lisina 6-Oxidase/genética , Proteína-Lisina 6-Oxidase/metabolismo , Neoplasias Gástricas/patologia
11.
Nat Commun ; 13(1): 3900, 2022 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-35794123

RESUMO

Ultra-wide bandgap semiconductor Ga2O3 based electronic devices are expected to perform beyond wide bandgap counterparts GaN and SiC. However, the reported power figure-of-merit hardly can exceed, which is far below the projected Ga2O3 material limit. Major obstacles are high breakdown voltage requires low doping material and PN junction termination, contradicting with low specific on-resistance and simultaneous achieving of n- and p-type doping, respectively. In this work, we demonstrate that Ga2O3 heterojunction PN diodes can overcome above challenges. By implementing the holes injection in the Ga2O3, bipolar transport can induce conductivity modulation and low resistance in a low doping Ga2O3 material. Therefore, breakdown voltage of 8.32 kV, specific on-resistance of 5.24 mΩ⋅cm2, power figure-of-merit of 13.2 GW/cm2, and turn-on voltage of 1.8 V are achieved. The power figure-of-merit value surpasses the 1-D unipolar limit of GaN and SiC. Those Ga2O3 power diodes demonstrate their great potential for next-generation power electronics applications.

12.
Front Surg ; 9: 920595, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35784926

RESUMO

Background: It has been reported that there is a correlation between the level of ubiquitin-specific protease 22 (USP22) and the clinicopathological parameters and prognosis of gastric cancer (GC) patients, but the conclusions are inconsistent. Hence, a meta-analysis must be conducted to clarify the relationship between USP22 expression and clinicopathological and prognostic value of GC patients to provide more accurate evidence. Methods: According to the predetermined selection criteria, systematic file retrieval was performed. The hazard ratio (HR) or odds ratio (OR) and its 95% confidence interval (CI) were used to evaluate the relationship between USP22 expression and clinicopathological and prognostic value of GC patients. Results: In a total of 802 patients, those with GC were finally included in 6 studies. The pooled results demonstrated that the expression of USP22 was significantly increased in GC tissues compared with control tissues (OR = 9.947, 95% CI, 6.074-16.291, P = 0.000), and USP22 expression was related to lymph node metastasis (OR = 2.415, 95% CI, 1.082, P = 0.031), distant metastasis (OR = 3.956, 95% CI, 1.365-11.464, P = 0.011) and TNM stage (OR = 2.973, 95% CI, 1.153-7.666, P = 0.024). Nevertheless, the expression of USP22 was not correlated with gender (OR = 1.202, 95% CI, 0.877-1.648, P = 0.253), age (OR = 1.090, 95% CI, 0.811-1.466, P = 0.568), tumor size (OR = 0.693,95% CI, 0.348-1.380, P = 0.297), tumor differentiation (OR = 1.830, 95%CI, 0.948-3.531, P = 0.072) and depth of invasion (OR = 2.320, 95% CI, 0.684-7.871, P = 0.177). Moreover, a high expression of USP22 predicted a poor overall survival (OS) in GC patients (HR = 2.012, 95% CI, 1.522-2.658, P = 0.000). The database of Kaplan-Meier plotter confirmed that a high expression of USP22 was correlated with poor prognostics in GC patients (HR = 1.41, 95% CI, 1.18-1.68, P < 0.01). Conclusion: USP22 overexpression in GC tissues is positively related to lymph node metastasis, distant metastasis and TNM stage and indicates a poor clinical outcome of GC patients, but it is not associated with age, gender, depth of invasion, tumor differentiation and tumor size of GC patients.Systematic Review Registration: https://www.crd.york.ac.uk/prospero/, identifier: 338361.

13.
Adv Mater ; 34(31): e2110664, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35680130

RESUMO

Topological crystalline insulators (TCIs) with hourglass fermion surface state have attracted a lot of attention and are further enriched by crystalline symmetries and magnetic order. Here, the emergence of hourglass fermion surface state and exotic phases in the newly discovered, air-stable ErAsS single crystals are shown. In the paramagnetic phase, ErAsS is expected to be a TCI with hourglass fermion surface state protected by the nonsymmorphic symmetry. Dirac-cone-like bands and nearly linear dispersions in large energy range are experimentally observed, consistent well with theoretical calculations. Below TN  ≈ 3.27 K, ErAsS enters a collinear antiferromagnetic state, which is a trivial insulator breaking the time-reversal symmetry. An intermediate incommensurate magnetic state appears in a narrow temperature range (3.27-3.65 K), exhibiting an abrupt change in magnetic coupling. The results reveal that ErAsS is an experimentally available TCI candidate and provide a unique platform to understand the formation of hourglass fermion surface state and explore magnetic-tuned topological phase transitions.

14.
Sci Total Environ ; 838(Pt 1): 155988, 2022 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-35584750

RESUMO

Studies showing that deserts can sequester CO2 through non-photosynthetic processes have contributed to locating missing carbon sinks. However, the contradiction between the desert CO2 flux obtained by different observation methods leads to uncertainty in evaluating desert carbon sequestration. This has caused scepticism regarding desert carbon sequestration after years of research. Through a comparative experiment in the non-vegetated shifting sand of the Taklimakan Desert (TD), it was found that if the abnormal negative CO2 flux observed by IRGASON during the day was not corrected, the carbon sequestration of the TD would be overestimated. The CO2 flux observed by EC155 is highly consistent with that of LI-COR8100A and can reflect the real CO2 exchange in the desert. The CO2 flux observed by EC155 was used to correct the results of IRGASON. Results show that the expansion/contraction of soil air containing CO2 caused by the change in the daily average soil temperature difference (T0-10cm) drives CO2 exchange in shifting sand. This results in diurnal variation of CO2 release caused by shifting sand during the day and CO2 absorption at night, and a unimodal distribution of CO2 exchange caused by shifting sand throughout the year. From April to September (T0-10cm > 2 °C), the shifting sand releases CO2 as a carbon source. In the other months (T0-10cm < 2 °C), the shifting sand absorbs CO2 as a carbon sink. The stronger absorption shows that the shifting sand in the TD provides carbon sequestration, with a CO2 uptake rate of ~148.85 × 104 tons a-1. This suggests that deserts play an active role in locating the missing carbon sinks and mitigating climate change, and that the status of deserts in the global carbon cycle cannot be ignored.


Assuntos
Dióxido de Carbono , Sequestro de Carbono , Carbono , Ciclo do Carbono , Dióxido de Carbono/análise , Ecossistema , Solo
15.
Org Lett ; 24(21): 3823-3827, 2022 06 03.
Artigo em Inglês | MEDLINE | ID: mdl-35604037

RESUMO

The diastereoselective synthesis of sulfonylated indolines is reported. A palladium-catalyzed dearomative sulfination of (aza)indole-tethered aryl iodides generates reactive benzylic sulfinates. These intermediates react with electrophiles in a one-pot, two-step process to generate sulfonylated products in good yields and excellent diastereoselectivity. This three-component sequence demonstrates good scalability and can be applied toward the synthesis of sulfonamides. Additionally, further derivatizations of aryl iodide containing products furnish spiro- and alkynylated indoline products.


Assuntos
Paládio , Sulfonamidas , Catálise , Iodetos
16.
BMC Gastroenterol ; 22(1): 142, 2022 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-35346069

RESUMO

BACKGROUND: The relationship between PROX1 expression and clinicopathological characteristics and prognosis in patients with gastric cancer (GC) remain controversial. The aim of this study is to determine the clinicopathological and prognostic significance of PROX1 expression in patients with GC. METHODS: A systematic literature search and meta-analysis were performed. Odds ratio (OR) and confidence interval (CI) were used to evaluated the relationship between PROX1 expression and clinicopathological characteristics and overall survival (OS) of GC patients. Additionally, the Cancer Genome Atlas (TCGA) and the Genotype-Tissue Expression (GTEx) datasets were utilized to examine the relationship between PROX1 expression and clinicopathological significance and OS in GC patients. RESULTS: A total of 8 studies pooling 1289 GC patients were included in the assessment. In GC patients, PROX1 expression was not related to gender (OR: 1.234, 95% CI 0.958-1.590, P = 0.104), depth of tumor invasion (OR: 0.742, 95% CI 0.428-1.287, P = 0.289), lymph node metastasis (OR: 2.161, 95% CI 0.808-5.779, P = 0.125), TNM stage (OR: 1.324, 95% CI 0.572-3.066, P = 0.513), tumor size (OR: 0.889, 95% CI 0.502-1.576, P = 0.687), distant metastasis (OR: 1.096, 95% CI 0.470-2.555, P = 0.763). In addition, we also found that PROX1 expression was not associated with 1-year OS (OR: 0.908, 95% CI 0.631-1.306, P = 0.602), 3-year OS (OR: 1.234, 95% CI 0.482-3.160, P = 0.661) and 5-year OS (OR: 0.853, 95% CI 0.266-2.736, P = 0.790). According to TCGA, in comparison with high and low PROX1 expression in GC patients, the OS did not differ statistically (p = 0.119). CONCLUSION: The expression of PROX1 was shown to lack a significant relationship to gender, TNM stage, depth of invasion, tumor size, stage, distant metastasis, or lymph node metastasis in statistically. The expression of PROX1 was not related to OS and it failed to be a meaningful biomarker to prevent and diagnose GC.


Assuntos
Proteínas de Homeodomínio , Neoplasias Gástricas , Proteínas Supressoras de Tumor , Proteínas de Homeodomínio/genética , Humanos , Metástase Linfática , Razão de Chances , Prognóstico , Neoplasias Gástricas/genética , Neoplasias Gástricas/patologia , Proteínas Supressoras de Tumor/genética
17.
Natl Sci Rev ; 8(8): nwaa218, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34691705

RESUMO

After the significant discovery of the hole-doped nickelate compound Nd0.8Sr0.2NiO2, analyses of the electronic structure, orbital components, Fermi surfaces and band topology could be helpful to understand the mechanism of its superconductivity. Based on first-principle calculations, we find that Ni [Formula: see text] states contribute the largest Fermi surface. The [Formula: see text] states form an electron pocket at Γ, while 5d xy states form a relatively bigger electron pocket at A. These Fermi surfaces and symmetry characteristics can be reproduced by our two-band model, which consists of two elementary band representations: B 1g @1a âŠ• A 1g @1b. We find that there is a band inversion near A, giving rise to a pair of Dirac points along M-A below the Fermi level upon including spin-orbit coupling. Furthermore, we perform density functional theory based Gutzwiller (DFT+Gutzwiller) calculations to treat the strong correlation effect of Ni 3d orbitals. In particular, the bandwidth of [Formula: see text] has been renormalized largely. After the renormalization of the correlated bands, the Ni 3d xy states and the Dirac points become very close to the Fermi level. Thus, a hole pocket at A could be introduced by hole doping, which may be related to the observed sign change of the Hall coefficient. By introducing an additional Ni 3d xy orbital, the hole-pocket band and the band inversion can be captured in our modified model. Besides, the nontrivial band topology in the ferromagnetic two-layer compound La3Ni2O6 is discussed and the band inversion is associated with Ni [Formula: see text] and La 5d xy orbitals.

18.
Front Oncol ; 11: 668946, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34568009

RESUMO

BACKGROUND: The clinicopathological and prognostic significance of SRY-box transcription factor 9 (SOX9) expression in gastric cancer (GC) patients is still controversial. Our aim is to investigate the clinicopathological and prognostic value of SOX9 expression in GC patients. METHODS: A systemic literature search and meta-analysis were used to evaluate the clinicopathological significance and overall survival (OS) of SOX9 expression in GC patients. The Cancer Genome Atlas (TCGA) dataset was used to investigate the relationship between SOX9 expression and OS of stomach adenocarcinoma (STAD) patients. RESULTS: A total of 11 articles involving 3,060 GC patients were included. In GC patients, the SOX9 expression was not associated with age [odds ratio (OR) = 0.743, 95% CI = 0.507-1.089, p = 0.128], sex (OR = 0.794, 95% CI = 0.605-1.042, p = 0.097), differentiation (OR = 0.728, 95% CI = 0.475-1.115, p = 0.144), and lymph node metastasis (OR = 1.031, 95% CI = 0.793-1.340, p = 0.820). SOX9 expression was associated with depth of invasion (OR = 0.348, 95% CI = 0.247-0.489, p = 0.000) and TNM stage (OR = 0.428, 95% CI = 0.308-0.595, p = 0.000). The 1-year OS (OR = 1.507, 95% CI = 1.167-1.945, p = 0.002), 3-year OS (OR = 1.482, 95% CI = 1.189-1.847, p = 0.000), and 5-year OS (OR = 1.487, 95% CI = 1.187-1.862, p = 0.001) were significantly shorter in GC patients with high SOX9 expression. TCGA analysis showed that SOX9 was upregulated in STAD patients compared with that in normal patients (p < 0.001), and the OS of STAD patients with a high expression of SOX9 is poorer than that in patients with low expression of SOX9, but the statistical difference is not obvious (p = 0.31). CONCLUSION: SOX9 expression was associated with the depth of tumor invasion, TNM stage, and poor OS of GC patients. SOX9 may be a potential prognostic factor for GC patients but needs further study. SYSTEMATIC REVIEW REGISTRATION: PROSPERO, ID NUMBER 275712.

19.
Ultrasonics ; 115: 106438, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33895526

RESUMO

The existing multi-sensor cluster acoustic emission (AE) source localization method has good positioning performance, but the parallel assumption in this method could cause positioning error. This paper focused on the analysis of the positioning error of multi-sensor cluster methods with sensor arrangements of isosceles right-angled triangle and triangular pyramid. Meanwhile, two and three-dimensional amendment algorithms for the two sensor arrangements were proposed. Pencil lead break experiments and numerical examples were used to verify the rationality of error source analysis and the accuracy of the amendment algorithms. Results show that the multi-sensor cluster methods can only accurately locate the AE sources in special positions, such as the AE sources satisfying θi = π/4 in the multi-sensor cluster method with a sensor arrangement of isosceles right-angled triangle and the AE sources satisfying cosθij=3/3 in the multi-sensor cluster method with a sensor arrangement of triangular pyramid. The results of pencil lead break experiment show that the two-dimensional amendment algorithm can accurately locate the AE sources in two-dimensional isotropic structure. For the two-dimensional anisotropic structure, the positioning result of the two-dimensional amendment algorithm is 27.8% higher than that of the multi-sensor cluster method with a sensor arrangement of isosceles right-angled triangle. The results of numerical examples show that the positioning errors of the multi-sensor cluster method with a sensor arrangement of triangular pyramid and the three-dimensional amendment algorithm are 24.6 mm and 0, respectively. Due to the correction of the positioning error caused by the parallel assumption, the latter has better positioning performance. Therefore, the amendment algorithms of the multi-sensor cluster methods have certain engineering application value in AE monitoring of two and three-dimensional structures.

20.
Nat Commun ; 12(1): 747, 2021 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-33531480

RESUMO

The simple ABO3 and A-site-ordered AA'3B4O12 perovskites represent two types of classical perovskite functional materials. There are well-known simple perovskites with ferroelectric properties, while there is still no report of ferroelectricity due to symmetry breaking transition in A-site-ordered quadruple perovskites. Here we report the high pressure synthesis of an A-site-ordered perovskite PbHg3Ti4O12, the only known quadruple perovskite that transforms from high-temperature centrosymmetric paraelectric phase to low-temperature non-centrosymmetric ferroelectric phase. The coordination chemistry of Hg2+ is changed from square planar as in typical A-site-ordered quadruple perovskite to a rare stereo type with 8 ligands in PbHg3Ti4O12. Thus PbHg3Ti4O12 appears to be a combinatory link from simple ABO3 perovskites to A-site-ordered AA'3Ti4O12 perovskites, sharing both displacive ferroelectricity with former and structure coordination with latter. This is the only example so far showing ferroelectricity due to symmetry breaking phase transition in AA'3B4O12-type A-site-ordered perovskites, and opens a direction to search for ferroelectric materials.

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