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1.
Nat Nanotechnol ; 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38750167

RESUMO

Exploration of new dielectrics with a large capacitive coupling is an essential topic in modern electronics when conventional dielectrics suffer from the leakage issue near the breakdown limit. Here, to address this looming challenge, we demonstrate that rare-earth metal fluorides with extremely low ion migration barriers can generally exhibit an excellent capacitive coupling over 20 µF cm-2 (with an equivalent oxide thickness of ~0.15 nm and a large effective dielectric constant near 30) and great compatibility with scalable device manufacturing processes. Such a static dielectric capability of superionic fluorides is exemplified by MoS2 transistors exhibiting high on/off current ratios over 108, ultralow subthreshold swing of 65 mV dec-1 and ultralow leakage current density of ~10-6 A cm-2. Therefore, the fluoride-gated logic inverters can achieve notably higher static voltage gain values (surpassing ~167) compared with a conventional dielectric. Furthermore, the application of fluoride gating enables the demonstration of NAND, NOR, AND and OR logic circuits with low static energy consumption. In particular, the superconductor-insulator transition at the clean-limit Bi2Sr2CaCu2O8+δ can also be realized through fluoride gating. Our findings highlight fluoride dielectrics as a pioneering platform for advanced electronic applications and for tailoring emergent electronic states in condensed matter.

2.
J Control Release ; 370: 354-366, 2024 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-38685387

RESUMO

Activation of the cyclic GMP-AMP synthase-stimulator of interferon genes (cGAS-STING) pathway is an effective way to initiate an immune response against tumors, and the research on agonists targeting STING has become a new hotspot in the development of antitumor drugs. However, as a novel STING agonist, the limited bioavailability and activation routes of manganese ions (Mn2+) significantly hinder its antitumor effects. To address these challenges, we have designed a metal-coordinated nucleoside metabolic inhibitor (gemcitabine, Gem)-induced metal nanotheranostic (MGP) with PEGylation. This formulation synergistically enhanced the immune response against cancer cells by sensitizing the cGAS-STING pathway and promoting immunogenic cell death (ICD). Modified with PEG derivatives, MGP was efficiently delivered to the tumor site and was internalized by cancer cells. Upon internalization, the release of Mn2+ triggered the activation of the cGAS-STING pathway, while the release of Gem induced DNA damage. On the one hand, the damaged DNA caused by Gem leaked into the cytoplasm, synergistically amplified Mn2+-induced activation of the cGAS-STING pathway, and induced the production of the tumor cytotoxic factor IFN-ß. On the other hand, Mn2+-mediated chemodynamic therapy (CDT) exhibited an ICD effect, which further synergized with the activation of the cGAS-STING pathway to promote dendritic cells (DCs) maturation and antigen-specific T cells infiltration. Both in vitro and in vivo studies have demonstrated that MGP nanotheranostics could elicit a robust antitumor effect, especially when combined with anti-PD-1. This study provided a new paradigm for intensifying immune activation by constructing metal coordination nanotheranostics.

3.
ACS Appl Bio Mater ; 7(2): 1229-1239, 2024 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-38254256

RESUMO

Chronic pain emerges as a major global health issue, significantly impacting individuals' health and quality of life. In this study, we designed a bilayer microneedle loaded with lidocaine nanocomposites in the inner layer and adrenaline (Adr) in the outer layer (HCP MNs) for modulated sequential release to achieve prolonged local anesthesia. The obtained HCP MNs featured an intact structure with adequate mechanical strength for efficient skin penetration. The bilayer structure of MNs was evidenced by loading two fluorescent dyes in each layer. Furthermore, these HCP MNs were capable of inducing rapid as well as prolonged local anesthetic effects in guinea pigs. Hence, the bilayer MN coloaded with Adr and lidocaine nanocomposite serves as a promising transdermal delivery platform for chronic pain management.


Assuntos
Anestesia Local , Lidocaína , Humanos , Animais , Cobaias , Lidocaína/química , Epinefrina , Qualidade de Vida , Sistemas de Liberação de Medicamentos
4.
Eur J Gastroenterol Hepatol ; 36(2): 203-209, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38047735

RESUMO

OBJECTIVE: This study aimed to investigate the association between novel inflammatory markers (NIMs) and non-alcoholic fatty liver disease (NAFLD). METHODS: A total of 6306 subjects were enrolled in this cross-sectional study. NIMs, including neutrophil to lymphocyte ratio (NLR), platelet to lymphocyte ratio (PLR), C-reactive protein to albumin ratio (CAR), lymphocyte to monocyte ratio (LMR), systemic immune-inflammation index (SII) and prognostic nutritional index (PNI), were calculated. The prevalence of NAFLD and its association with NIMs were assessed by multivariable logistic regression analysis. Subgroup analysis were performed based on age, sex and BMI. RESULTS: The prevalence of NAFLD was 52.5% in the study population. Compared with non-NAFLD subjects, NAFLD patients were older and more frequent in females. The prevalence of NAFLD progressively increased among the higher quartile groups of CAR, LMR, SII and PNI ( P -trend < 0.05), whereas it progressively decreased among the higher quartile group of NLR and PLR ( P -trend < 0.05). According to multivariable logistic regression analysis, the highest quartile (Q4) had a significantly higher risk of NAFLD compared with Q1 in LMR [odds ratio (OR): 1.43; 95% confidence interval (CI): 1.17-1.75; P -trend < 0.001] and PNI (OR: 1.92; 95% CI: 1.57-2.35; P -trend < 0.001). The subgroup analysis showed a stronger association of PNI with NAFLD. CONCLUSION: The study highlights the association between NIMs and NAFLD, with LMR and PNI identified as potential non-invasive markers of inflammation in NAFLD. Specifically, PNI exhibited the strongest association and may serve as a valuable marker for assessing inflammation in NAFLD.


Assuntos
Hepatopatia Gordurosa não Alcoólica , Feminino , Humanos , Hepatopatia Gordurosa não Alcoólica/diagnóstico , Hepatopatia Gordurosa não Alcoólica/epidemiologia , Estudos Transversais , Linfócitos , Avaliação Nutricional , Inflamação/diagnóstico , Inflamação/epidemiologia , Neutrófilos , Estudos Retrospectivos , Prognóstico
5.
Chronic Dis Transl Med ; 9(4): 320-328, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37915384

RESUMO

Background: Although multiple measures of blood pressure variability (BPV) have been proposed, whether they are better than mean blood pressure in predicting target organs is unclear. We aimed to determine the relationship between short term BPV and target organ injury. Methods: This study was a retrospective study, and 635 inpatients in the Department of Cardiology from 2015 to 2020 were selected. We divided participants into four groups on the basis of the quartiles of BPV. One-way analysis of variance was used to compare the differences between the groups, and linear regression was used to analyze the relationship between BPV and target organ damage. Results: The average age of 635 patients was 74.36 ± 6.50 years old. Among them, 354 of 627 patients had diminished renal function (56.5%), 221of 604 patients had associated left ventricular hypertrophy (36.6%), and 227 of 231 patients had carotid plaque formation (98.3%). The baseline data indicated significant differences in fasting glucose, total cholesterol, low-density lipoprotein, creatinine, glomerular filtration rate, sex, calcium channel blocker use, and the rate of diminished renal function. Multiple linear regression analysis showed that BPV was negatively correlated with renal injury (creatinine: r = 0.306, p < 0.01; estimated glomerular filtration rate: r = 0.058, p < 0.01), and BPV is positively correlated with cardiac injury (r = 0.083, p < 0.01). Elevated BPV was not found to be associated with vascular injury. Conclusion: Renal function decreases with increasing BPV and left ventricular mass increases with increasing BPV.

6.
Nano Lett ; 23(22): 10282-10289, 2023 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-37906179

RESUMO

Quasiparticles consisting of correlated electron(s) and hole(s), such as excitons and trions, play important roles in the optical phenomena of van der Waals semiconductors and serve as unique platforms for studies of many-body physics. Herein, we report a gate-tunable exciton-to-trion transition in pressurized monolayer MoSe2, in which the electronic band structures are modulated continuously within a diamond anvil cell. The emission energies of both the exciton and trion undergo large blueshifts over 90 meV with increasing pressure. Surprisingly, the trion binding energy remains constant at 30 meV, regardless of the applied pressure. Combining ab initio density functional theory calculations and quantum Monte Carlo simulations, we find that the remarkable robustness of the trion binding energy originates from the spatially diffused nature of the trion wave function and the weak correlation between its constituent electron-hole pairs. Our findings shed light on the optical properties of correlated excitonic quasiparticles in low-dimensional materials.

7.
Sci Adv ; 9(36): eadf6758, 2023 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-37683003

RESUMO

Two-dimensional superconductivity is primarily realized in atomically thin layers through extreme exfoliation, epitaxial growth, or interfacial gating. Apart from their technical challenges, these approaches lack sufficient control over the Fermiology of superconducting systems. Here, we offer a Fermiology-engineering approach, allowing us to desirably tune the coherence length of Cooper pairs and the dimensionality of superconducting states in arsenic phosphides AsxP1-x under hydrostatic pressure. We demonstrate how this turns these compounds into tunable two-dimensional superconductors with a dome-shaped phase diagram even in the bulk limit. This peculiar behavior is shown to result from an unconventional valley-dimensionality locking mechanism, driven by a delicate competition between three-dimensional hole-type and two-dimensional electron-type energy pockets spatially separated in momentum space. The resulting dimensionality crossover is further discussed to be systematically controllable by pressure and stoichiometry tuning. Our findings pave a unique way to realize and control superconducting phases with special pairing and dimensional orders.

8.
Nat Commun ; 14(1): 5568, 2023 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-37689758

RESUMO

Van der Waals dielectrics are fundamental materials for condensed matter physics and advanced electronic applications. Most dielectrics host isotropic structures in crystalline or amorphous forms, and only a few studies have considered the role of anisotropic crystal symmetry in dielectrics as a delicate way to tune electronic properties of channel materials. Here, we demonstrate a layered anisotropic dielectric, SiP2, with non-symmorphic twofold-rotational C2 symmetry as a gate medium which can break the original threefold-rotational C3 symmetry of MoS2 to achieve unexpected linearly-polarized photoluminescence and anisotropic second harmonic generation at SiP2/MoS2 interfaces. In contrast to the isotropic behavior of pristine MoS2, a large conductance anisotropy with an anisotropy index up to 1000 can be achieved and modulated in SiP2-gated MoS2 transistors. Theoretical calculations reveal that the anisotropic moiré potential at such interfaces is responsible for the giant anisotropic conductance and optical response. Our results provide a strategy for generating exotic functionalities at dielectric/semiconductor interfaces via symmetry engineering.

9.
Chin Med J (Engl) ; 136(20): 2442-2450, 2023 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-37677929

RESUMO

BACKGROUND: Atherosclerosis-related diseases represent significant health issues among adults globally. Despite their widespread impact, comprehensive data concerning the global and national burden and trends of these diseases remain sparse. Our objective is to examine the trends in the burden of atherosclerosis among adults from 1990 to 2019 at both global and national levels. METHODS: We reported the average annual percentage changes (AAPCs) in prevalence, incidence, mortality, and disability-adjusted life years (DALYs) of atherosclerosis-related diseases (ischemic heart disease [IHD], ischemic stroke, and peripheral arterial disease [PAD]) at the global and national levels among individuals based on a trend analysis of the Global Burden of Diseases Study (GBD) 2019. We further analyzed these global trends as a function of age, gender, and the social development index. We also used joinpoint regression analysis to identify the year with the most substantial changes in global trends. RESULTS: Globally, the AAPC of IHD incidence rose from 1990 to 2019 (0.20; 95% confidence interval [CI], 0.12-0.28), with substantial surges in 1995, 2001, 2005, 2010, and 2017. Conversely, AAPC of IHD mortality rates exhibited a different trend until a rise in 2014. The AAPC of incidence rates of ischemic stroke and PAD also escalated during the same period, with respective 0.43 (95% CI, 0.39-0.48) and 0.13 (95% CI, 0.06-0.21). For ischemic stroke, both incidence and mortality soared in 2014, while PAD incidence declined in 1994 and 1998, then sharply climbed in 2016. Nationally, the Northern Mariana Islands experienced the steepest increase in IHD and PAD incidence and mortality between 1990 and 2019. China saw a significant rise in ischemic stroke incidence, whereas the highest mortality rate increase occurred in Timor-Leste. By sociodemographic index (SDI) quintile, low-middle-, middle-, and high-middle-SDI countries all showed upward trends in IHD, ischemic stroke, and PAD incidence. Simultaneously, IHD and ischemic stroke mortality rates, as well as DALYs, dropped in the low-, high-middle-, and high-SDI nations. However, PAD mortality rates and DALYs saw an uptick across all SDI quintiles. Regarding age demographics, a global decrease in the AAPC IHD incidence as noted in individuals above 55 years old, in contrast to an increase in the 20-55 age group during this period. AAPC of mortality rates for IHD, ischemic stroke, and PAD decreased across all ages. The AAPC showed an increase in IHD incidence in both genders. Conversely, IHD's DALYs saw a reduction in both males and females. Ischemic stroke patterns mirrored these trends, whereas all measures for PAD exhibited growth for both sexes. CONCLUSIONS: From 1990 to 2019, there was an overall increasing trend in the global incidence of all three clinical manifestations of atherosclerosis. Between 1990 and 2019, both the mortality rate and DALYs for IHD and ischemic stroke declined across all age groups. Overall, the burden of atherosclerosis-related diseases has not significantly decreased and even shows signs of trending upward. These findings strongly suggest that despite some progress made, efforts to control atherosclerosis diseases globally need to be intensified.


Assuntos
Aterosclerose , AVC Isquêmico , Isquemia Miocárdica , Adulto , Humanos , Masculino , Feminino , Pessoa de Meia-Idade , Carga Global da Doença , Anos de Vida Ajustados por Qualidade de Vida , Aterosclerose/epidemiologia , Isquemia Miocárdica/epidemiologia , Incidência
10.
J Am Chem Soc ; 145(29): 15869-15878, 2023 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-37449950

RESUMO

Designing new synthesis routes to fabricate highly thermally durable precious metal single-atom catalysts (SACs) is challenging in industrial applications. Herein, a general strategy is presented that starts from dual-metal nanocrystals (NCs), using bimetallic NCs as a facilitator to spontaneously convert a series of noble metals to single atoms on aluminum oxide. The metal single atoms are captured by cation defects in situ formed on the surface of the inverse spinel (AB2O4) structure, which process provides numerous anchoring sites, thus facilitating generation of the isolated metal atoms that contributes to the extraordinary thermodynamic stability. The Pd1/AlCo2O4-Al2O3 shows not only improved low-temperature activity but also unprecedented (hydro)thermal stability for CO and propane oxidation under harsh aging conditions. Furthermore, our strategy exhibits a small scaling-up effect by the simple physical mixing of commercial metal oxide aggregates with Al2O3. The good regeneration between oxidative and reductive atmospheres of these ionic palladium species makes this catalyst system of potential interest for emissions control.

11.
Nat Nanotechnol ; 18(8): 867-874, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37322146

RESUMO

The Berry curvature dipole (BCD) is a key parameter that describes the geometric nature of energy bands in solids. It defines the dipole-like distribution of Berry curvature in the band structure and plays a key role in emergent nonlinear phenomena. The theoretical rationale is that the BCD can be generated at certain symmetry-mismatched van der Waals heterointerfaces even though each material has no BCD in its band structure. However, experimental confirmation of such a BCD induced via breaking of the interfacial symmetry remains elusive. Here we demonstrate a universal strategy for BCD generation and observe BCD-induced gate-tunable spin-polarized photocurrent at WSe2/SiP interfaces. Although the rotational symmetry of each material prohibits the generation of spin photocurrent under normal incidence of light, we surprisingly observe a direction-selective spin photocurrent at the WSe2/SiP heterointerface with a twist angle of 0°, whose amplitude is electrically tunable with the BCD magnitude. Our results highlight a BCD-spin-valley correlation and provide a universal approach for engineering the geometric features of twisted heterointerfaces.

12.
Intern Emerg Med ; 18(5): 1385-1396, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37195594

RESUMO

Adjusting antiplatelet strategies after antiplatelet-associated gastrointestinal bleeding (GIB) is a complex clinical challenge. To assess the risk of outcomes at different times of resumption of antiplatelet therapy in an attempt to find the optimal time to resume therapy. The study analyzed consecutive patients with antiplatelet-associated GIB from Beijing Friendship Hospital Information System between October 2019 and June 2022. The primary outcomes were recurrent bleeding, major adverse cardiovascular and cerebrovascular events (MACE), and all-cause death. Multivariate-adjusted Cox proportional hazards models were used to evaluate the risks of these outcomes. The receiver operating characteristic curve was used to find the optimal time to resume treatment. Of the 617 patients with GIB after antiplatelet therapy successfully followed up, the median follow-up was 246 (interquartile range: 120-466) days, most patients (87.36%) interrupted therapy after GIB and 45.22% resumed within 90 days, of which 35.13% resumed within 7 days and 64.87% resumed after 7 days. Resumption therapy had a low risk of recurrent bleeding (uninterrupted as a reference: HR 0.32, 95% CI 0.15-0.67, p = 0.003), MACE (no resumption as a reference: HR 0.66, 95% CI 0.45-0.98, p = 0.037), and all-cause death (no resumption as a reference: HR 0.18, 95% CI 0.08-0.40, p < 0.001). And resuming therapy within 7 days had a lower risk of MACE (HR 0.18, 95% CI 0.08-0.44, p < 0.001) than after 7 days without a significantly higher risk of re-bleeding. The optimal time point for resuming therapy in this study was 8.5 days. Resuming antiplatelet therapy after GIB provides better clinical benefits compared to discontinued and uninterrupted therapy, especially compared with resuming after 7 days, resuming within 7 days is associated with a lower risk of MACE and a less significant increased risk of recurrent bleeding, leading to a higher net clinical benefit. China Clinical Trial Registration: ChiCTR2200064063.


Assuntos
Hemorragia Gastrointestinal , Inibidores da Agregação Plaquetária , Humanos , Inibidores da Agregação Plaquetária/efeitos adversos , Hemorragia Gastrointestinal/induzido quimicamente , Hemorragia Gastrointestinal/terapia , Risco , China , Anticoagulantes/uso terapêutico
13.
Chin Med J (Engl) ; 136(8): 959-966, 2023 04 20.
Artigo em Inglês | MEDLINE | ID: mdl-37014764

RESUMO

BACKGROUND: Limited data are available on the comparison of clinical outcomes of complete vs. incomplete percutaneous coronary intervention (PCI) for patients with chronic total occlusion (CTO) and multi-vessel disease (MVD). The study aimed to compare their clinical outcomes. METHODS: A total of 558 patients with CTO and MVD were divided into the optimal medical treatment (OMT) group ( n = 86), incomplete PCI group ( n = 327), and complete PCI group ( n = 145). Propensity score matching (PSM) was performed between the complete and incomplete PCI groups as sensitivity analysis. The primary outcome was defined as the occurrence of major adverse cardiovascular events (MACEs), and unstable angina was defined as the secondary outcome. RESULTS: At a median follow-up of 21 months, there were statistical differences among the OMT, incomplete PCI, and complete PCI groups in the rates of MACEs (43.0% [37/86] vs. 30.6% [100/327] vs. 20.0% [29/145], respectively, P = 0.016) and unstable angina (24.4% [21/86] vs. 19.3% [63/327] vs. 10.3% [15/145], respectively, P = 0.010). Complete PCI was associated with lower MACE compared with OMT (adjusted hazard ratio [HR] = 2.00; 95% confidence interval [CI] = 1.23-3.27; P = 0.005) or incomplete PCI (adjusted HR = 1.58; 95% CI = 1.04-2.39; P = 0.031). Sensitivity analysis of PSM showed similar results to the above on the rates of MACEs between complete PCI and incomplete PCI groups (20.5% [25/122] vs. 32.6% [62/190], respectively; adjusted HR = 0.55; 95% CI = 0.32-0.96; P = 0.035) and unstable angina (10.7% [13/122] vs. 20.5% [39/190], respectively; adjusted HR = 0.48; 95% CI = 0.24-0.99; P = 0.046). CONCLUSIONS: For treatment of CTO and MVD, complete PCI reduced the long-term risk of MACEs and unstable angina, as compared with incomplete PCI and OMT. Complete PCI in both CTO and non-CTO lesions can potentially improve the prognosis of patients with CTO and MVD.


Assuntos
Oclusão Coronária , Intervenção Coronária Percutânea , Humanos , Resultado do Tratamento , Intervenção Coronária Percutânea/métodos , Oclusão Coronária/cirurgia , Prognóstico , Angina Instável/cirurgia , Doença Crônica , Fatores de Risco
14.
Cell Discov ; 9(1): 37, 2023 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-37015915

RESUMO

The pandemic of COVID-19 caused by SARS-CoV-2 continues to spread around the world. Mutant strains of SARS-CoV-2 are constantly emerging. At present, Omicron variants have become mainstream. In this work, we carried out a systematic and comprehensive analysis of the reported spike protein antibodies, counting the epitopes and genotypes of these antibodies. We further comprehensively analyzed the impact of Omicron mutations on antibody epitopes and classified these antibodies according to their binding patterns. We found that the epitopes of the H-RBD class antibodies were significantly less affected by Omicron mutations than other classes. Binding and virus neutralization experiments showed that such antibodies could effectively inhibit the immune escape of Omicron. Cryo-EM results showed that this class of antibodies utilized a conserved mechanism to neutralize SARS-CoV-2. Our results greatly help us deeply understand the impact of Omicron mutations. Meanwhile, it also provides guidance and insights for developing Omicron antibodies and vaccines.

15.
Polymers (Basel) ; 15(6)2023 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-36987240

RESUMO

The in situ electrochemical oxidation process has received considerable attention for the removal of dye molecules and ammonium from textile dyeing and finishing wastewater. Nevertheless, the cost and durability of the catalytic anode have seriously limited industrial applications of this technique. In this work, the lab-based waste polyvinylidene fluoride membrane was employed to fabricate a novel lead dioxide/polyvinylidene fluoride/carbon cloth composite (PbO2/PVDF/CC) via integrated surface coating and electrodeposition processes. The influences of operating parameters (pH, Cl- concentration, current density, and initial concentration of pollutant) on the oxidation efficiency of PbO2/PVDF/CC were evaluated. Under optimal conditions, this composite achieves a 100% decolorization of methyl orange (MO), 99.48% removal of ammonium, and 94.46% conversion for ammonium-based nitrogen to N2, as well as an 82.55% removal of chemical oxygen demand (COD). At the coexistent condition of ammonium and MO, MO decolorization, ammonium, and COD removals still remain around 100%, 99.43%, and 77.33%, respectively. It can be assigned to the synergistic oxidation effect of hydroxyl radical and chloride species for MO and the chlorine oxidation action for ammonium. Based on the determination of various intermediates, MO is finally mineralized to CO2 and H2O, and ammonium is mainly converted to N2. The PbO2/PVDF/CC composite exhibits excellent stability and safety.

16.
Adv Mater ; 35(19): e2211409, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36808146

RESUMO

Superconducting quantum interferometer device (SQUID) plays a key role in understanding electromagnetic properties and emergent phenomena in quantum materials. The technological appeal of SQUID is that its detection accuracy for the electromagnetic signal can precisely reach the quantum level of a single magnetic flux. However, conventional SQUID techniques normally can only be applied to a bulky sample and do not have the capability to probe the magnetic properties of micro-scale samples with small magnetic signals. Herein, it is demonstrated that, based on a specially designed superconducting nano-hole array, the contactless detection of magnetic properties and quantized vortices in micro-sized superconducting nanoflakes is realized. An anomalous hysteresis loop and a suppression of Little-Parks oscillation are observed in the detected magnetoresistance signal, which originates from the disordered distribution of the pinned vortices in Bi2 Sr2 CaCu2 O8+δ . Therefore, the density of pinning centers of the quantized vortices on such micro-sized superconducting samples can be quantitatively evaluated, which is technically inaccessible for conventional SQUID detection. The superconducting micro-magnetometer provides a new approach to exploring mesoscopic electromagnetic phenomena of quantum materials.

17.
Hellenic J Cardiol ; 69: 9-15, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36509330

RESUMO

OBJECTIVE: This study aimed to assess the effects of coronary collateral circulation (CCC) on the prognosis of patients with chronic total occlusion (CTO) under different treatment strategies. METHODS: We analyzed a total of 1124 patients who were diagnosed with CTO and divided them into groups with good CCC (grade 2 to 3, n = 539) or poor CCC (grade 0 to 1, n = 531). The primary outcome was cardiac death during follow-up; the secondary outcome was major adverse cardiovascular events (MACEs). We also performed subgroup analyses in groups with and without CTO revascularization (CTO-R and CTO-NR, respectively), and sensitivity analyses excluding patients who received failed CTO-PCI to further investigate the effect of CCC. RESULTS: During a median follow-up duration of 23 months, we did not detect any significant differences between the good CCC group and the poor CCC group in terms of cardiac death (4.2% vs 4.1%; adjusted hazard ratio [HR], 1.01; 95% confidence interval [CI], 0.56-1.83; p = 0.970) and MACEs (23.6% vs 23.2%; adjusted HR, 1.07; 95% CI, 0.84-1.37; p = 0.590). Subgroup analyses according to CTO revascularization showed similar results. In addition, we observed no differences in sensitivity analyses when patients who received failed CTO-PCI were excluded. CONCLUSION: Good CCC was not associated with a lower risk of cardiac death or MACEs among patients with CTO, regardless of whether the patients received CTO revascularization treatment.


Assuntos
Oclusão Coronária , Intervenção Coronária Percutânea , Humanos , Intervenção Coronária Percutânea/efeitos adversos , Circulação Colateral , Oclusão Coronária/diagnóstico , Oclusão Coronária/cirurgia , Oclusão Coronária/etiologia , Prognóstico , Morte , Doença Crônica , Resultado do Tratamento , Fatores de Risco
18.
Nat Commun ; 13(1): 6938, 2022 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-36376300

RESUMO

Valence fluctuation of interacting electrons plays a crucial role in emergent quantum phenomena in correlated electron systems. The theoretical rationale is that this effect can drive a band insulator into a superconductor through charge redistribution around the Fermi level. However, the root cause of such a fluctuating leap in the ionic valency remains elusive. Here, we demonstrate a valence-skipping-driven insulator-to-superconductor transition and realize quasi-two-dimensional superconductivity in a van der Waals insulator GeP under pressure. This is shown to result from valence skipping of the Ge cation, altering its average valency from 3+ to 4+, turning GeP from a layered compound to a three-dimensional covalent system with superconducting critical temperature reaching its maximum of 10 K. Such a valence-skipping-induced superconductivity with a quasi-two-dimensional nature in thin samples, showing a Berezinskii-Kosterlitz-Thouless-like character, is further confirmed by angle-dependent upper-critical-field measurements. These findings provide a model system to examine competing order parameters in valence-skipping systems.

19.
Chemosphere ; 307(Pt 4): 136132, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36002064

RESUMO

In this work, a three-dimensional self-supporting copper/cobalt phosphide/nickel foam (Co/CoP/NF) composite was fabricated and employed as the cathode for electrochemical nitrate removal from surface water with the assistance of a commercial Ir-Ru/Ti anode. The experimental results demonstrate that the introduction of Cu nanoparticles on CoP nanosheets is favorable for the electrocatalytic nitrate reduction. The influences of operating parameters (pH value, current density and initial nitrate concentration) on the nitrate reduction were assessed with the presence of Cl-. At the optimized conditions, the removal of nitrate exhibits an efficiency ca. 100% via the coupling electrochemical reduction and oxidation processes. Moreover, the nitrogen selectivity is found to be as high as 98.8% within 210 min, accompanied with a promising test endurance (>94.0% for total nitrogen (TN) and NO3- removal efficiencies after an electrochemical run of 24.5 h). Importantly, as for the treated actual surface water, the concentration of TN is smaller than 1.5 mg L-1, in accordance with the limit of Ⅳ-level standard of the surface water environmental quality in China (GB 3838-2002). The efficient removal of nitrate can be attributed to the synergistic effect of Cu and CoP microparticles to enhance the reduction activity, as well as the subsequent chloride oxidation for the major intermediate of ammonium.


Assuntos
Compostos de Amônio , Nitratos , Cloretos , Cobre , Eletrodos , Níquel , Nitrogênio , Óxidos de Nitrogênio , Titânio , Água
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