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Cardiovascular disease (CVD) is a global health concern, presenting significant risks to human health. Atherosclerosis is among the most prevalent CVD, impacting the medium and large arteries in the kidneys, brain, heart, and other vital organs, as well as the lower limbs. As the disease progresses, arterial obstruction can result in heart attacks and strokes. Therefore, patients with atherosclerosis should receive accurate diagnosis and timely therapeutic intervention. With the advancements in nanomedicine, researchers have proposed new research strategies and methods for atherosclerosis imaging. This paper summarizes some current research findings on the use of nanomaterials in diagnosing atherosclerosis and offers insights for optimizing the imaging applications of nanomaterials in the future.
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Aterosclerose , Humanos , Aterosclerose/diagnóstico , Aterosclerose/diagnóstico por imagem , Nanotecnologia , Nanoestruturas/química , AnimaisRESUMO
The unprecedented phenomenon that a charge density wave (CDW) emerges inside the antiferromagnetic (AFM) phase indicates an unusual CDW mechanism associated with magnetism in FeGe. Here, we demonstrate that both the CDW and magnetism of FeGe can be effectively tuned through postgrowth annealing treatments. Instead of the short-range CDW reported earlier, a long-range CDW order is realized below 110 K in single crystals annealed at 320 °C for over 48 h. The CDW and AFM transition temperatures appear to be inversely correlated with each other. The onset of the CDW phase significantly reduces the critical field of the spin-flop transition, whereas the CDW transition remains stable against minor variations in magnetic orders such as annealing-induced magnetic clusters and spin-canting transitions. Single-crystal x-ray diffraction measurements reveal substantial disorder on the Ge1 site, which is characterized by displacement of the Ge1 atom from the Fe_{3}Ge layer along the c axis and can be reversibly modified by the annealing process. The observed annealing-tunable CDW and magnetic orders can be well understood in terms of disorder on the Ge1 site. Our study provides a vital starting point for the exploration of the unconventional CDW mechanism in FeGe and of kagome materials in general.
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Exotic quantum states arise from the interplay of various degrees of freedom such as charge, spin, orbital, and lattice. Recently, a short-ranged charge order (CO) was discovered deep inside the antiferromagnetic phase of Kagome magnet FeGe, exhibiting close relationships with magnetism. Despite extensive investigations, the CO mechanism remains controversial, mainly because the short-ranged behavior hinders precise identification of CO superstructure. Here, combining multiple experimental techniques, we report the observation of a long-ranged CO in high-quality FeGe samples, which is accompanied with a first-order structural transition. With these high-quality samples, the distorted 2 × 2 × 2 CO superstructure is characterized by a strong dimerization along the c-axis of 1/4 of Ge1-sites in Fe3Ge layers, and in response to that, the 2 × 2 in-plane charge modulations are induced. Moreover, we show that the previously reported short-ranged CO might be related to large occupational disorders at Ge1-site, which upsets the equilibrium of the CO state and the ideal 1 × 1 × 1 structure with very close energies, inducing nanoscale coexistence of these two phases. Our study provides important clues for further understanding the CO properties in FeGe and helps to identify the CO mechanism.
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Non-centrosymmetric topological material has attracted intense attention due to its superior characteristics as compared with the centrosymmetric one, although probing the local quantum geometry in non-centrosymmetric topological material remains challenging. The non-linear Hall (NLH) effect provides an ideal tool to investigate the local quantum geometry. Here, we report a non-centrosymmetric topological phase in ZrTe5, probed by using the NLH effect. The angle-resolved and temperature-dependent NLH measurement reveals the inversion and ab-plane mirror symmetries breaking at <30 K, consistently with our theoretical calculation. Our findings identify a new non-centrosymmetric phase of ZrTe5 and provide a platform to probe and control local quantum geometry via crystal symmetries.
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The Berry curvature dipole (BCD) serves as a one of the fundamental contributors to emergence of the nonlinear Hall effect (NLHE). Despite intense interest due to its potential for new technologies reaching beyond the quantum efficiency limit, the interplay between BCD and NLHE has been barely understood yet in the absence of a systematic study on the electronic band structure. Here, we report NLHE realized in NbIrTe4 that persists above room temperature coupled with a sign change in the Hall conductivity at 150 K. First-principles calculations combined with angle-resolved photoemission spectroscopy (ARPES) measurements show that BCD tuned by the partial occupancy of spin-orbit split bands via temperature is responsible for the temperature-dependent NLHE. Our findings highlight the correlation between BCD and the electronic band structure, providing a viable route to create and engineer the non-trivial Hall effect by tuning the geometric properties of quasiparticles in transition-metal chalcogen compounds.
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Patient blood management (PBM) guidelines for patients undergoing cardiac surgery under cardiopulmonary bypass (CPB) have increased during the past decade, and pharmacotherapy plays an important role in PBM. In the face of the undefined consistency in the methodologic quality and pharmacotherapy recommendations across multiple guidelines, this study exclusively evaluated methodologies of the related guideline development process, and compiled medication recommendations of PBM for cardiac surgery patients. PBM guidelines for cardiac surgery under CPB were searched through some mainstream literature and guideline databases from database establishment to May 15, 2023. Nine guidelines meeting inclusion criteria were included in this study. The quality of the guidelines was evaluated using the Appraisal of Guidelines for Research and Evaluation II (AGREE II) tool. "Stakeholder involvement" received the lowest mean score of 49.38% in the AGREE II scoring among the guidelines. PBM for cardiac surgery patients spans the perioperative phase. Drug therapy strategies of PBM for cardiac surgery patients involve anemia therapy, perioperative administration of antithrombotic drugs, intraoperative anticoagulation, and the use of hemostatic drugs. Unlike for adults, there is less evidence about the management of antithrombotic drugs and hemostatic drugs for pediatric cardiac surgery patients. Recombinant activated factor VII (rFVIIa) and desmopressin (DDAVP) are not recommended after pediatric cardiac surgery, whereas prothrombin complex concentrate could be considered in clinical trials. As for the controversies regarding the administration of rFVIIa and DDAVP after adult cardiac surgery by different societies, clinicians should exercise their clinical judgment based on individual patient features.
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Procedimentos Cirúrgicos Cardíacos , Ponte Cardiopulmonar , Guias de Prática Clínica como Assunto , Humanos , Ponte Cardiopulmonar/métodos , Ponte Cardiopulmonar/normas , Procedimentos Cirúrgicos Cardíacos/métodos , Guias de Prática Clínica como Assunto/normasRESUMO
We report a comprehensive study of the nanoscale inhomogeneity and disorder on the thermoelectric properties of FeSe[Formula: see text]S[Formula: see text] ([Formula: see text]) single crystals and the evolution of correlation strength with S substitution. A hump-like feature in temperature-dependent thermpower is enhanced for x = 0.12 and 0.14 in the nematic region with increasing in orbital-selective electronic correlations, which is strongly suppressed across the nematic critical point and for higher S content. Nanoscale Se/S atom disorder in the tetrahedral surroundings of Fe atoms is confirmed by scanning transmission electron microscopy measurements, providing an insight into the nanostructural details and the evolution of correlation strength in FeSe[Formula: see text]S[Formula: see text].
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The Berry curvature and quantum metric are the imaginary part and real part, respectively, of the quantum geometric tensor, which characterizes the topology of quantum states1. The Berry curvature is known to generate a number of important transport phenomena, such as the quantum Hall effect and the anomalous Hall effect2,3; however, the consequences of the quantum metric have rarely been probed by transport measurements. Here we report the observation of quantum-metric-induced nonlinear transport, including both a nonlinear anomalous Hall effect and a diode-like non-reciprocal longitudinal response, in thin films of a topological antiferromagnet, MnBi2Te4. Our observations reveal that the transverse and longitudinal nonlinear conductivities reverse signs when reversing the antiferromagnetic order, diminish above the Néel temperature and are insensitive to disorder scattering, thus verifying their origin in the band-structure topology. They also flip signs between electron- and hole-doped regions, in agreement with theoretical calculations. Our work provides a means to probe the quantum metric through nonlinear transport and to design magnetic nonlinear devices.
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Triazoles are common agents for invasive fungal infections, while therapeutic drug monitoring is needed to improve antifungal efficacy and reduce toxicity. This study aimed to exploit a simple and reliable liquid chromatography-mass spectrometry method for high-throughput monitoring of antifungal triazoles in human plasma using UPLC-QDa. Triazoles in plasma were separated by chromatography on a Waters BEH C18 column and detected using positive ions electrospray ionization fitted with single ion recording. M+ for fluconazole (m/z 307.11) and voriconazole (m/z 350.12), M2+ for posaconazole (m/z 351.17), itraconazole (m/z 353.13) and ketoconazole (m/z 266.08, IS) were selected as representative ions in single ion recording mode. The standard curves in plasma showed acceptable linearities over 1.25-40 µg/mL for fluconazole, 0.47-15 µg/mL for posaconazole and 0.39-12.5 µg/mL for voriconazole and itraconazole. The selectivity, specificity, accuracy, precision, recovery, matrix effect, and stability met acceptable practice standards under Food and Drug Administration method validation guidelines. This method was successfully applied to the therapeutic monitoring of triazoles in patients with invasive fungal infections, thereby guiding clinical medication.
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Antifúngicos , Infecções Fúngicas Invasivas , Humanos , Itraconazol , Voriconazol , Fluconazol , Espectrometria de Massas em Tandem/métodos , Triazóis , Cromatografia Líquida de Alta Pressão/métodos , Reprodutibilidade dos TestesRESUMO
Rockbursts have important influences on construction safety, so the risk assessment of rockburst intensity has great significance. Firstly, the depth of the rockburst, the uniaxial compressive strength, the stress concentration coefficients, the brittleness coefficients, and the elastic energy index are selected as the evaluation index. Secondly, an assessment model is developed based on the fuzzy variable theory. And the model is proposed to assess the rockburst intensity in the highway tunnel. Finally, the results demonstrate that the results derived from the proposed model are consistent with the current specifications; the accurate rate comes to 100%. The method can determine the risk level of rockburst intensity and provide an alternative scheme. Hence, the study can accurately present a new approach to assess the rockburst intensity in the future.