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The pursuit of discovering new high-temperature superconductors that diverge from the copper-based model1-3 has profound implications for explaining mechanisms behind superconductivity and may also enable new applications4-8. Here our investigation shows that the application of pressure effectively suppresses the spin-charge order in trilayer nickelate La4Ni3O10-δ single crystals, leading to the emergence of superconductivity with a maximum critical temperature (Tc) of around 30 K at 69.0 GPa. The d.c. susceptibility measurements confirm a substantial diamagnetic response below Tc, indicating the presence of bulk superconductivity with a volume fraction exceeding 80%. In the normal state, we observe a strange metal behaviour, characterized by a linear temperature-dependent resistance extending up to 300 K. Furthermore, the layer-dependent superconductivity observed hints at a unique interlayer coupling mechanism specific to nickelates, setting them apart from cuprates in this regard. Our findings provide crucial insights into the fundamental mechanisms underpinning superconductivity, while also introducing a new material platform to explore the intricate interplay between the spin-charge order, flat band structures, interlayer coupling, strange metal behaviour and high-temperature superconductivity.
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Materials manifesting the Kitaev model, characterized by bond-dependent interactions on a honeycomb lattice, can host exotic phenomena like quantum spin liquid states and topological magnetic excitations. However, finding such materials remains a formidable challenge. Here, we report high-resolution inelastic neutron scattering measurements performed on VI_{3}, a van der Waals ferromagnetic Mott insulator, covering a wide range of reciprocal space. Our measurements unveil highly anisotropic magnetic excitations in momentum space. Through a comprehensive comparative analysis of various models that incorporate diverse symmetry-allowed magnetic interactions, we find the observed excitations are well captured by a model with a large bond-dependent Kitaev interaction. These results not only help to understand the intriguing properties of VI_{3}, such as the pronounced anomalous thermal Hall effects and strong pressure or structure dependence of magnetism, but also open a new avenue for exploring Kitaev physics.
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BACKGROUND: Allogeneic hematopoietic stem cell transplantation (allo-HSCT) has been identified as the potentially curative treatment for high-risk acute lymphoblastic leukemia (ALL) in adult patients. However, relapse of the disease and/or development of graft-versus-host disease (GVHD) remain to be the most common barriers for successful allo-HSCT. Preclinical studies showed that ruxolitinib, a Janus tyrosine kinase (Jak)1 and Jak2 inhibitor, has a selective anti-GVHD effects while preserving a potent graft-versus-leukemia (GVL) effect. Our study aimed to investigate the efficacy and safety in early application of ruxolitinib for the high-risk ALL patients to prevent GVHD. METHODS: There were eight patients undergoing allo-HSCT at the Bone Marrow Transplantation Center of the Third Xiangya Hospital of Central South University between April 2020 and April 2021. Ruxolitinib (5-10 mg twice daily) was administered early (median time: 45 days) after stem cell infusion. RESULTS: After a median follow-up of 14 months (range from 8 to 18 months), the ALL disease relapse occurred in two cases. Among all eight patients, two of them developed grade I/II acute (a) GVHD, while no patient developed grade III/IV aGVHD, and one patient developed chronic (c) GVHD. As for the virus activation, no patient developed EBV activation or EBV related lymphoproliferative disease, and three patients developed CMV activation. Our results suggest that the early application of ruxolitinib could safely and effectively prevent the occurrence of GVHD after allo-HSCT for the high-risk ALL patients. However, it may have a limited effect on preventing the recurrence of high-risk ALL and thus may require additional therapy with other anti-relapse drugs. CONCLUSIONS: Our preliminary observations suggest that an early application of ruxolitinib can safely and effectively prevent the occurrence of GVHD after allo-HSCT for the high-risk ALL patients. However, ruxolitinib may have a limited effect on preventing the ALL recurrence of high-risk patients.
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Doença Enxerto-Hospedeiro , Transplante de Células-Tronco Hematopoéticas , Nitrilas , Leucemia-Linfoma Linfoblástico de Células Precursoras , Pirazóis , Pirimidinas , Adulto , Humanos , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Doença Enxerto-Hospedeiro/prevenção & controle , Leucemia-Linfoma Linfoblástico de Células Precursoras/etiologia , Doença Aguda , Doença Crônica , Recidiva , Estudos RetrospectivosRESUMO
Purpose: The deleterious impact of aggressive behavior on college students necessitates urgent mitigation. To explore the influencing factors and underlying mechanisms of aggressive behaviors among college students, this study aims to validate the mediating roles of life satisfaction, meaning in life, and depression by examining the relationship between physical exercise and aggressive behaviors among college students. Methods: The Physical Activity Rating Scale-3 (PARS-3), Satisfaction with Life Scale, Meaning in Life Questionnaire, Chinese Version DASS-21 and 12-item Perception of Aggression Scale (POAS) were tested on 1596 college students from three universities in western China, and SPSS 26.0 and Mplus 8.3 were used for analysis. Results: Physical exercise exhibited a significant negative correlation with both aggressive behaviors and depression among college students (r = -0.57, P < 0.001; r = -0.36, P < 0.001), as well as a significant positive correlation with life satisfaction and meaning in life (r = 0.45, P < 0.001; r = 0.27, P < 0.001). Regarding the impact of physical exercise on aggressive behaviors among college students, the mediating effects of life satisfaction, meaning in life, and depression were significant. The respective effect sizes were -0.11, -0.08, and -0.03. The chain mediation effect of life satisfaction through depression was also found to be significant, with an effect size of -0.02. Conclusion: This study elucidates the mechanistic pathways through which physical exercise influences aggressive behavior among college students. The relationship between physical exercise and aggressive behavior is influenced by the individual mediating effects of life satisfaction, meaning in life, and depression, as well as the chain mediation effect of life satisfaction through depression. These findings provide a novel perspective on the prevention and intervention of aggressive behaviors among college students in China and potentially worldwide. This suggests that more attention should be paid to the organic combination of students' physical activity and mental health education.
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Introduction: The potential positive impact of computer game playing on cognitive function and its potential role in reducing the risk of Alzheimer's disease (AD) has been suggested. However, current observational studies have certain limitations. We utilized Mendelian randomization (MR) alongside extensive genome-wide association study (GWAS) data to examine the relationship between computer game playing, cognitive function, risk of AD, and levels of brain-derived neurotrophic factor (BDNF). Methods: We collected datasets on computer game playing, cognition function, risk of AD, and BDNF level from the IEU Open GWAS project. Causal effects were assessed using various MR methods, including inverse variance weighted (IVW), weighted median, MR-Egger, simple mode, and weighted mode. To ensure the accuracy of the results, sensitivity analyses were conducted. Results: Our analysis revealed a significant association between computer game playing and cognitive function (ß = 0.801, 95% CI: 0.351, 1.328, P = 0.001). There was no statistically significant association between computer game playing and either BDNF level or risk of AD (ß = -0.112, 95%CI: -1.315, 1.091, P = 0.855; OR = 1.000, 95% CI: 1.004, 0.997, P = 0.891, respectively). We further confirmed the reliability of our evidence through the MR-Egger intercept test, MR-PRESSO global test, Cochran's Q test, and funnel plots. Conclusion: The results of our study indicate that engaging in computer game playing may confer a safeguarding influence on cognitive function. This underscores the potential advantages associated with computer gaming. Nevertheless, given the constraints inherent in our research, further investigation is warranted to substantiate our findings and delve into the underlying mechanisms.
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Polyhydroxyalkanoates (PHAs) could be used to make sustainable, biodegradable plastics. However, the precise and accurate mechanistic modeling of PHA biosynthesis, especially medium-chain-length PHA (mcl-PHA), for yield improvement remains a challenge to biology. PHA biosynthesis is typically triggered by nitrogen limitation and tends to peak at an optimal carbon-to-nitrogen (C/N) ratio. Specifically, simulation of the underlying dynamic regulation mechanisms for PHA bioprocess is a bottleneck owing to surfeit model complexity and current modeling philosophies for uncertainty. To address this issue, we proposed a quantum-like decision-making model to encode gene expression and regulation events as hidden layers by the general transformation of a density matrix, which uses the interference of probability amplitudes to provide an empirical-level description for PHA biosynthesis. We implemented our framework modeling the biosynthesis of mcl-PHA in Pseudomonas putida with respect to external C/N ratios, showing its optimization production at maximum PHA production of 13.81% cell dry mass (CDM) at the C/N ratio of 40:1. The results also suggest the degree of P. putida's preference in channeling carbon towards PHA production as part of the bacterium's adaptative behavior to nutrient stress using quantum formalism. Generic parameters (kD, kN and theta θ) obtained based on such quantum formulation, representing P. putida's PHA biosynthesis with respect to external C/N ratios, was discussed. This work offers a new perspective on the use of quantum theory for PHA production, demonstrating its application potential for other bioprocesses.