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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: Menopause hormone therapy (MHT), as an effective method to alleviate the menopause-related symptoms of women, its benefits, risks, and potential influencing factors for the cardiovascular system of postmenopausal women are not very clear. OBJECTIVES: To evaluate cardiovascular benefits and risks of MHT in postmenopausal women, and analyze the underlying factors that affect both. SEARCH STRATEGY: The EMBASE, MEDLINE, and CENTRAL databases were searched from 1975 to July 2022. SELECTION CRITERIA: Randomized Clinical Trials (RCTs) that met pre-specified inclusion criteria were included. DATA COLLECTION AND ANALYSIS: Two reviewers extracted data independently. A meta-analysis of random effects was used to analyze data. MAIN RESULTS: This systematic review identified 33 RCTs using MHT involving 44,639 postmenopausal women with a mean age of 60.3 (range 48 to 72 years). There was no significant difference between MHT and placebo (or no treatment) in all-cause death (RR = 0.96, 95%CI 0.85 to 1.09, I2 = 14%) and cardiovascular events (RR = 0.97, 95%CI 0.82 to 1.14, I2 = 38%) in the overall population of postmenopausal women. However, MHT would increase the risk of stroke (RR = 1.23, 95%CI 1.08 to 1.41,I2 = 0%) and venous thromboembolism (RR = 1.86, 95%CI 1.39 to 2.50, I2 = 24%). Compared with placebo, MHT could improve flow-mediated arterial dilation (FMD) (SMD = 1.46, 95%CI 0.86 to 2.07, I2 = 90%), but it did not improve nitroglycerin-mediated arterial dilation (NMD) (SMD = 0.27, 95%CI - 0.08 to 0.62, I2 = 76%). Compared with women started MHT more than 10 years after menopause, women started MHT within 10 years after menopause had lower frequency of all-cause death (P = 0.02) and cardiovascular events (P = 0.002), and more significant improvement in FMD (P = 0.0003). Compared to mono-estrogen therapy, the combination therapy of estrogen and progesterone would not alter the outcomes of endpoint event. (all-cause death P = 0.52, cardiovascular events P = 0.90, stroke P = 0.85, venous thromboembolism P = 0.33, FMD P = 0.46, NMD P = 0.27). CONCLUSIONS: MHT improves flow-mediated arterial dilation (FMD) but fails to lower the risk of all-cause death and cardiovascular events, and increases the risk of stroke and venous thrombosis in postmenopausal women. Early acceptance of MHT not only reduces the risk of all-cause death and cardiovascular events but also further improves FMD, although the risk of stroke and venous thrombosis is not reduced. There is no difference in the outcome of cardiovascular system endpoints between mono-estrogen therapy and combination therapy of estrogen and progesterone.
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Acidente Vascular Cerebral , Tromboembolia Venosa , Trombose Venosa , Feminino , Humanos , Pessoa de Meia-Idade , Idoso , Pós-Menopausa , Progesterona , Artérias , Estrogênios , Terapia de Reposição Hormonal , Medição de RiscoRESUMO
African swine fever virus (ASFV) is a kind of DNA virus and can infect both domestic pigs and wild boars with fatality up to 100%. The contaminated meat products mainly led to the worldwide transmission of ASFV. The outbreak of ASF greatly affects the supply stability of meat products as well as the development of the global pig industry. In this study, a visual isothermal amplification detection assay for ASFV based on trimeric G-quadruplex cis-cleavage activity of Cas12a was developed. The introduction of Cas12a could discriminate the specific amplification from the non-specific amplification and improve the sensitivity. The detection limit was as low as 0.23 copies/µL. This assay had good potential in the detection of ASFV and would be helpful for the stability of meat production and supply.
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Vírus da Febre Suína Africana , Febre Suína Africana , Suínos , Animais , Vírus da Febre Suína Africana/genética , Febre Suína Africana/diagnóstico , Febre Suína Africana/epidemiologia , Sus scrofaRESUMO
OBJECTIVE: To observe the combination effects of Panax notoginseng saponins (PNS)and dual antiplatelet drugs (DAPT), and to explore the mechanism via cyclooxygenase /prostaglandin pathway. METHODS: Right carotid artery thrombosis was induced in Wistar rats by infiltration with 70% FeCl3, and the animals were randomly divided into sham group, model group, DAPT group and PNS + DAPT group, intragastrically treated for 4 weeks. The cerebral pia mater microcirculation was observed in vivo after anesthetizing by anatomical microscope. The wet weight of carotid artery thrombosis was measured. Gastric mucosal injury was observed by hematoxylin and eosin staining. Platelet aggregation rate was detected with adenosine diphosphate -induced turbidimetry. Platelet CD62p expression was detected by flow cytometry. Concentrations of 6-Ketoprostaglandin F1 alpha, prostaglandin E2 in gastric mucosa and thromboxane B2, 6-Ketoprostaglandin F1 alpha, tissue plasminogen activator, plasminogen activator inhibitor, and fibrin fragment D in the plasma were measured by radioimmunoassay. RESULTS: PNS and DAPT increased the blood flow volume of cerebral pia mater and decreased erythrocyte aggregation and leukocyte adhesion of model rats. Compared to DAPT, PNS and DAPT further reduced the weight of carotid artery thrombosis with enhanced inhibition of platelet aggregation, increased tissue plasminogen activator levels and decreased fibrin fragment D levels. PNS and DAPT alleviated gastric injury induced by dual antiplatelet drugs and upregulated the expression of 6-Ketoprostaglandin F1 alpha in the gastric mucosa compared with DAPT. CONCLUSIONS: PNS combined with DAPT increased anti-thrombosis effects of DAPT and mitigated DAPT-related gastric injury. The underlying mechanisms may be associated with enhanced antiplatelet aggregation and activation of the fibrinolytic system and up-regulation of 6-Ketoprostaglandin F1 alpha expression in gastric mucosa.
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Trombose das Artérias Carótidas , Panax notoginseng , Saponinas , Trombose , 6-Cetoprostaglandina F1 alfa , Animais , Trombose das Artérias Carótidas/tratamento farmacológico , Inibidores da Agregação Plaquetária/farmacologia , Ratos , Ratos Wistar , Saponinas/farmacologia , Trombose/tratamento farmacológico , Trombose/prevenção & controle , Ativador de Plasminogênio Tecidual/farmacologiaRESUMO
We report neutron scattering measurements of the spinel oxide LiGaCr_{4}O_{8}, in which magnetic ions Cr^{3+} form a breathing pyrochlore lattice. Our experiments reveal the coexistence of a nearly dispersionless resonance mode and dispersive spin-wave excitations in the magnetically ordered state, which can be quantitatively described by a quantum spin model of hexagonal loops and linear spin-wave theory with the same set of exchange parameters, respectively. Comparison to other Cr spinel oxides reveals a linear relationship between the resonance energy and lattice constant across all these materials, which is in agreement with our hexagonal loop calculations. Our results suggest a unified picture for spin resonances in Cr spinel oxides.
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Purpose: The study aims to evaluate the effects of high-intensity and moderate-intensity exercise training on cardiopulmonary function and exercise endurance in patients with coronary artery diseases (CAD). Methods: We performed a systematic search of the English and Chinese databases from their inception to March 2022. Randomized controlled trials (RCTs) were included to compare high-intensity and moderate-intensity exercise training on cardiopulmonary function in patients with CAD. The primary outcomes included peak oxygen uptake (peak VO2) and anaerobic threshold (AT). The secondary outcomes included left ventricular ejection fraction (LVEF), exercises duration (ED), respiratory exchange ratio (RER), resting heart rate (RHR), peak heart rate (PHR) and oxygen pulse (O2 pulse). The continuous variables were expressed as mean differences (MD) along with their corresponding standard deviations (SD), and the I2 test was applied in the assessment of heterogeneity. Results: After systematically literature search, 19 studies were finally selected for our meta-analysis (n = 1,036), with 511 patients in the experimental group (high-intensity exercise) and 525 patients in the control group (moderate-intensity exercise). The results showed that high-intensity exercise significantly increased patients' Peak VO2 [MD = 2.67, 95% CI (2.24, 3.09), P < 0.00001], LVEF [MD = 3.60, 95% CI (2.17, 5.03), P < 0.00001], ED [MD = 37.51, 95% CI (34.02, 41.00), P < 0.00001], PHR [MD = 6.86, 95% CI (4.49, 9.24), P < 0.00001], and O2 pulse [MD = 0.97, 95% CI (0.34, 1.60), P = 0.003] compared with moderate-intensity exercise. However, there were no significant differences in AT [MD = 0.49, 95% CI (-0.12, 1.10), P = 0.11], RER [MD = 0.00, 95% CI (-0.01, 0.02), P = 0.56], and RHR [MD = 1.10, 95% CI (-0.43, 2.63), P = 0.16]. Conclusion: Our results show that high-intensity exercise training has more significant positive effects compared with moderate-intensity exercise training in improving peak VO2, LVEF, ED, PHR and O2 pulse in patients with CAD, while no significant differences were observed in AT, RER and RHR. To sum up, high-intensity exercise training is better than moderate-intensity exercise training in improving cardiopulmonary function and exercise endurance in patients with CAD. Systematic review registration: PROSPERO (CRD42022328475), https://www.crd.york.ac.uk/PROSPERO/.
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Ischemic heart disease is a significant risk factor that threatens human health, and antiplatelet drugs are routinely used to treat cases in clinical settings. Chinese medicine for promoting blood circulation and removing blood stasis (PBCRBSCM) can often be combined with antiplatelet drugs to treat ischemic heart disease. PBCRBSCM can inhibit platelet adhesion, activation, and aggregation; moreover, PBCRBSCM in combination with antiplatelet drugs exerts antiplatelet effects. The mechanism is related to several factors, including the inhibition of platelet activation and aggregation, improvement of the hemodynamic status and coagulation function, and correction of metabolism and inflammation. PBCRBSCM can also regulate the absorption and metabolism of conventional antiplatelet drugs and protect the gastric mucosal epithelial cells against damage induced by conventional antiplatelet drugs. Randomized controlled trials have confirmed that PBCRBSCM preparations and the active ingredients in these preparations can reduce resistance to aspirin and clopidogrel so that the combination of these drugs can exert their antiplatelet effects. In the perioperative treatment of patients with stable angina pectoris, unstable angina pectoris, and acute coronary syndrome undergoing percutaneous coronary intervention therapy, preparations of the active ingredients of PBCRBSCM combined with antiplatelet drugs and other conventional Western medicine treatments have been proven effective. The efficacy and safety of such combinations have also been extensively verified. Considerable progress has been made to understand the antiplatelet mechanism of PBCRBSCM. However, most clinical studies had problems, such as limited sample size and inappropriate research design, which has limited the translational use of PBCRBSCM in antiplatelet therapy. A large-scale, multicenter, randomized controlled study with cardiovascular events as the endpoint is still to be conducted to provide evidence for the combined application of PBCRBSCM and antiplatelet drugs in the prevention and treatment of ischemic heart disease.