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1.
Int J Biol Macromol ; 269(Pt 2): 132212, 2024 May 08.
Article En | MEDLINE | ID: mdl-38729495

Polyphenols, polysaccharides, and proteins are essential nutrients and functional substances present in food, and when present together these components often interact with each other to influence their structure and function. Proteins and polysaccharides are also excellent carrier materials for polyphenols. In this context, this study investigated the non-covalent interactions between taxifolin (TAX), Lentinus edodes mycelia polysaccharide (LMP), and ß-casein (ß-CN). ß-CN and LMP spontaneously formed nanocomplexes by hydrogen bonds and van der Waals forces. The quenching constant and binding constant were (1.94 ± 0.02) × 1013 L mol-1 s-1 and (3.22 ± 0.17) × 105 L mol-1 at 298 K, respectively. The altered conformation of ß-CN, resulting from the binding to LMP, affected the interaction with TAX. LMP significantly enhanced the binding affinity of TAX and ß-CN, but did not change the static quenching binding mode. The binding constant for ß-CN-TAX was (3.96 ± 0.09) × 1013 L mol-1, and that for the interaction between TAX and ß-CN-LMP was (32.06 ± 0.05) × 1013 L mol-1. In summary, ß-CN-LMP nanocomplexes have great potential as a nanocarrier for polyphenols, and this study provides a theoretical foundation for the rational design of non-covalent complexes involving LMP and ß-CN, both in binary and ternary configurations.

2.
Phys Chem Chem Phys ; 26(19): 14194-14204, 2024 May 15.
Article En | MEDLINE | ID: mdl-38713135

Constructing Z-scheme heterojunctions incorporating an exquisite hollow structure is an effective performance regulation strategy for the realization of high quantum efficiency and a strong redox ability over photocatalysts. Herein, we report the delicate design and preparation of a core-shell hollow CdS@CoTiO3 Z-scheme heterojunction with a CdS nanoparticle (NP)-constructed outer shell supported on a CoTiO3 nanorod (NR) inner shell. The in situ growth synthetic method led to a tightly connected interface for the heterojunction between CdS and CoTiO3, which shortened the transport distance of photoinduced charges from the interface to the surface. The promoted charge carrier separation efficiency and the retained strong redox capacity caused by the Z-scheme photoinduced charge-transfer mechanism were mainly responsible for the boosted photocatalytic performance. Additionally, the well-designed core-shell structure afforded a larger interfacial area by the multiple direction contact between CdS and CoTiO3, ensuring sufficient channels for efficient charge transfer, and thus further boosting the photocatalytic activity. As an efficient photocatalyst, the optimized CdS@CoTiO3 nanohybrids displayed excellent 2,4-dichlorophenol (2,4-DCP) and tetracycline (TC) degradation efficiencies of 91.3% and 91.8%, respectively. This study presents a Z-scheme heterojunction based on ecofriendly CoTiO3, which could be valuable for the development of metal perovskite photocatalysts for application in environmental remediation, and also demonstrated the tremendous potential of integrating a Z-scheme heterojunction with the morphology design of photocatalyts.

3.
Environ Geochem Health ; 46(6): 197, 2024 May 02.
Article En | MEDLINE | ID: mdl-38696118

Micro/nanoplastics (MNPs) are emerging as environmental pollutants with potential threats to human health. The accumulation of MNPs in the body can cause oxidative stress and increase the risk of cardiovascular disease (CVD). With the aim to systematically evaluate the extent of MNPs-induced oxidative damage and serum biochemical parameters in rats and mice, a total of 36 eligible articles were included in this meta-analysis study. The results reported that MNPs can significantly increase the levels of oxidants such as reactive oxygen species (ROS) and malondialdehyde (MDA) (P < 0.05), and resulted in notable increase in serum biochemical parameters including aspartate aminotransferase (AST) and alanine aminotransferase (ALT) (P < 0.05). Conversely, MNPs significantly reduced levels of antioxidants such as superoxide dismutase (SOD), glutathione (GSH), glutathione peroxidase (GPx) and catalase (CAT) (P < 0.05). Subgroup analysis revealed that smaller MNPs with oral administration and prolonged treatment, were associated with more pronounced oxidative stress and enhanced serum biochemical parameters alteration. In addition, after affected by MNPs, the levels of ALT and AST in liver group (SMD = 2.26, 95% CI = [1.59, 2.94] and SMD = 3.10, 95% CI = [1.25, 4.94]) were higher than those in other organs. These comprehensive results provide a scientific foundation for devising strategies to prevent MNPs-induced damage, contributing to solution of this environmental and health challenge.


Oxidative Stress , Animals , Oxidative Stress/drug effects , Rats , Mice , Aspartate Aminotransferases/blood , Microplastics/toxicity , Alanine Transaminase/blood , Antioxidants/metabolism , Reactive Oxygen Species/metabolism , Liver/drug effects , Liver/metabolism , Environmental Pollutants/toxicity , Nanoparticles , Malondialdehyde/blood , Superoxide Dismutase/metabolism
4.
Front Public Health ; 12: 1333811, 2024.
Article En | MEDLINE | ID: mdl-38605869

Background: In recent years, an increasing number of observational studies have reported the impact of air pollution on autoimmune diseases (ADs). However, no Mendelian randomization (MR) studies have been conducted to investigate the causal relationships. To enhance our understanding of causality, we examined the causal relationships between particulate matter (PM) and nitrogen oxides (NOx) and ADs. Methods: We utilized genome-wide association study (GWAS) data on PM and NOx from the UK Biobank in European and East Asian populations. We also extracted integrated GWAS data from the Finnish consortium and the Japanese Biobank for two-sample MR analysis. We employed inverse variance weighted (IVW) analysis to assess the causal relationship between PM and NOx exposure and ADs. Additionally, we conducted supplementary analyses using four methods, including IVW (fixed effects), weighted median, weighted mode, and simple mode, to further investigate this relationship. Results: In the European population, the results of MR analysis suggested a statistically significant association between PM2.5 and psoriasis only (OR = 3.86; 95% CI: 1.89-7.88; PIVW < 0.00625), while a potential association exists between PM2.5-10 and vitiligo (OR = 7.42; 95% CI: 1.02-53.94; PIVW < 0.05), as well as between PM2.5 and systemic lupus erythematosus (OR = 68.17; 95% CI: 2.17-2.1e+03; PIVW < 0.05). In East Asian populations, no causal relationship was found between air pollutants and the risk of systemic lupus erythematosus and rheumatoid arthritis (PIVW > 0.025). There was no pleiotropy in the results. Conclusion: Our results suggest a causal association between PM2.5 and psoriasis in European populations. With the help of air pollution prevention and control, the harmful progression of psoriasis may be slowed.


Air Pollution , Autoimmune Diseases , Lupus Erythematosus, Systemic , Psoriasis , Humans , Genome-Wide Association Study , Mendelian Randomization Analysis , Autoimmune Diseases/etiology , Autoimmune Diseases/genetics , Air Pollution/adverse effects , Particulate Matter/adverse effects , Psoriasis/etiology , Psoriasis/genetics
5.
Int J Biol Macromol ; 267(Pt 1): 131387, 2024 May.
Article En | MEDLINE | ID: mdl-38582470

A novel Lentinus edodes mycelia polysaccharide (LMP) prepared in our laboratory has been identified to be effective in inhibiting the damage of islet ß cells induced by glucose toxicity. However, whether it can effectively alleviate the pyroptosis of human umbilical vein endothelial cells (HUVECs) induced by advanced glycation end products (AGEs) remains unclear. Bioinformatics and cell biology techniques were used to explore the mechanism of LMP inhibiting AGEs-induced HUVECs damage. The results indicated that AGEs significantly increased the expression of LncRNA MALAT1, decreased cell viability to 79.67 %, increased intracellular ROS level to 248.19 % compared with the control group, which further led to cell membrane rupture. The release of LDH in cellular supernatant was increased to 149.42 %, and the rate of propidium iodide staining positive cells increased to 277.19 %, indicating the cell pyroptosis occurred. However, the above trend was effectively retrieved after the treatment with LMP. LMP effectively decreased the expression of LncRNA MALAT1 and mTOR, promoted the expression of miR-199b, inhibited AGEs-induced HUVECs pyroptosis by regulating the NLRP3/Caspase-1/GSDMD pathway. LncRNA MALAT1 might be a new target for LMP to inhibit AGEs-induced HUVECs pyroptosis. This study manifested the role of LMP in improving diabetes angiopathy and broadens the application of polysaccharide.


Caspase 1 , Gasdermins , Glycation End Products, Advanced , Human Umbilical Vein Endothelial Cells , MicroRNAs , Mycelium , NLR Family, Pyrin Domain-Containing 3 Protein , Pyroptosis , RNA, Long Noncoding , Shiitake Mushrooms , Signal Transduction , TOR Serine-Threonine Kinases , Humans , RNA, Long Noncoding/genetics , RNA, Long Noncoding/metabolism , Pyroptosis/drug effects , NLR Family, Pyrin Domain-Containing 3 Protein/metabolism , Human Umbilical Vein Endothelial Cells/drug effects , Human Umbilical Vein Endothelial Cells/metabolism , TOR Serine-Threonine Kinases/metabolism , MicroRNAs/genetics , MicroRNAs/metabolism , Caspase 1/metabolism , Shiitake Mushrooms/chemistry , Glycation End Products, Advanced/metabolism , Signal Transduction/drug effects , Mycelium/chemistry , Phosphate-Binding Proteins/metabolism , Phosphate-Binding Proteins/genetics , Intracellular Signaling Peptides and Proteins/metabolism , Intracellular Signaling Peptides and Proteins/genetics , Fungal Polysaccharides/pharmacology , Fungal Polysaccharides/chemistry , Cell Survival/drug effects , Polysaccharides/pharmacology , Polysaccharides/chemistry
6.
J Funct Biomater ; 15(4)2024 Apr 18.
Article En | MEDLINE | ID: mdl-38667566

In recent years, the use of zinc (Zn) alloys as degradable metal materials has attracted considerable attention in the field of biomedical bone implant materials. This study investigates the fabrication of porous scaffolds using a Zn-1Mg-0.1Sr alloy through a three-dimensional (3D) printing technique, selective laser melting (SLM). The results showed that the porous Zn-1Mg-0.1Sr alloy scaffold featured a microporous structure and exhibited a compressive strength (CS) of 33.71 ± 2.51 MPa, a yield strength (YS) of 27.88 ± 1.58 MPa, and an elastic modulus (E) of 2.3 ± 0.8 GPa. During the immersion experiments, the immersion solution showed a concentration of 2.14 ± 0.82 mg/L for Zn2+ and 0.34 ± 0.14 mg/L for Sr2+, with an average pH of 7.61 ± 0.09. The porous Zn-1Mg-0.1Sr alloy demonstrated a weight loss of 12.82 ± 0.55% and a corrosion degradation rate of 0.36 ± 0.01 mm/year in 14 days. The Cell Counting Kit-8 (CCK-8) assay was used to check the viability of the cells. The results showed that the 10% and 20% extracts significantly increased the activity of osteoblast precursor cells (MC3T3-E1), with a cytotoxicity grade of 0, which indicates safety and non-toxicity. In summary, the porous Zn-1Mg-0.1Sr alloy scaffold exhibits outstanding mechanical properties, an appropriate degradation rate, and favorable biosafety, making it an ideal candidate for degradable metal bone implants.

7.
Nano Lett ; 24(17): 5125-5131, 2024 May 01.
Article En | MEDLINE | ID: mdl-38639405

We report a study of thickness-dependent interband and intraband magnetic breakdown by thermoelectric quantum oscillations in ZrSiSe nanoplates. Under high magnetic fields of up to 30 T, quantum oscillations arising from degenerated hole pockets were observed in thick ZrSiSe nanoplates. However, when decreasing the thickness, plentiful multifrequency quantum oscillations originating from hole and electron pockets are captured. These multiple frequencies can be explained by the emergent interband magnetic breakdown enclosing individual hole and electron pockets and intraband magnetic breakdown within spin-orbit coupling (SOC) induced saddle-shaped electron pockets, resulting in the enhanced contribution to thermal transport in thin ZrSiSe nanoplates. These experimental frequencies agree well with theoretical calculations of the intriguing tunneling processes. Our results introduce a new member of magnetic breakdown to the field and open up a dimension for modulating magnetic breakdown, which holds fundamental significance for both low-dimensional topological materials and the physics of magnetic breakdown.

8.
Phys Rev Lett ; 132(11): 110201, 2024 Mar 15.
Article En | MEDLINE | ID: mdl-38563920

We propose a solvable model of quantum Darwinism to encoding transitions-abrupt changes in how quantum information spreads in a many-body system under unitary dynamics. We consider a random Clifford circuit on an expanding tree, whose input qubit is entangled with a reference. The model has a quantum Darwinism phase, where one classical bit of information about the reference can be retrieved from an arbitrarily small fraction of the output qubits, and an encoding phase where such retrieval is impossible. The two phases are separated by a mixed phase and two continuous transitions. We compare the exact result to a two-replica calculation. The latter yields a similar "annealed" phase diagram, which applies also to a model with Haar random unitaries. We relate our approach to measurement-induced phase transitions (MIPTs), by solving a modified model where an environment eavesdrops on an encoding system. It has a sharp MIPT only with full access to the environment.

9.
Digit Health ; 10: 20552076241241381, 2024.
Article En | MEDLINE | ID: mdl-38550266

Background: Hyperuricemia is a common complication of type 2 diabetes mellitus and can lead to serious consequences such as gout and kidney disease. Methods: Patients with type 2 diabetes mellitus from six different communities in Fuzhou were recruited from June to December 2022. Questionnaires, physical examinations, and laboratory tests were conducted to collect data on various variables. Variable screening steps were performed using univariate and multivariate stepwise regression, least absolute shrinkage and selection operator (LASSO) regression, and Boruta feature selection. The dataset was divided into a training-testing set (80%) and an independent validation set (20%). Six machine learning models were built and validated. Results: A total of 8243 patients with type 2 diabetes mellitus were included in this study. According to Occam's razor method, the LASSO regression algorithm was determined to be the optimal risk factors selection method, and nine variables were identified as parameters for the risk assessment model. The absence of diabetes medication and elevated fasting blood glucose levels exhibited a negative correlation with the risk of hyperuricemia. Conversely, seven other variables demonstrated a positive association with the risk of hyperuricemia among patients diagnosed with type 2 diabetes mellitus. Among the six machine learning models, the artificial neural network (ANN) model demonstrated the highest performance. It achieved an areas under curve of 0.736, accuracy of 68.3%, sensitivity of 65.0%, specificity of 72.2%, precision of 73.6% and F1-score of 69.0%. Conclusions: We developed an ANN model to better evaluate the risk of hyperuricemia in the type 2 diabetes population. In the type 2 diabetes population, women should pay particular attention to their uric acid levels, and type 2 diabetics should not neglect their obesity level, blood pressure, kidney function and lipid profile during their regular medical check-ups, in order to do their best to avoid the risks associated with the combination of type 2 diabetes and hyperuricemia.

10.
Environ Res ; 251(Pt 1): 118534, 2024 Feb 22.
Article En | MEDLINE | ID: mdl-38395336

TatD DNase, a key enzyme in vertebrates and invertebrates, plays a pivotal role in various physiological processes. Dugesia japonica (D. japonica), a flatworm species, has remarkable regenerative capabilities and possesses a simplified immune system. However, the existence and biological functions of TatD DNase in D. japonica require further investigation. Here, we obtained the open reading frame (ORF) of DjTatD and demonstrated its conservation. The three-dimensional structure of DjTatD revealed its active site and binding mechanism. To investigate its enzymological properties, we overexpressed, purified, and characterized recombinant DjTatD (rDjTatD). We observed that DjTatD was primarily expressed in the pharynx and its expression could be significantly challenged upon stimulation with lipopolysaccharide, peptidoglycan, gram-positive and gram-negative bacteria. RNA interference results indicated that both DjTatD and DjDN2s play a role in pharyngeal regeneration and may serve as functional complements to each other. Additionally, we found that rDjTatD and recombinant T7DjTatD effectively reduce biofilm formation regardless of their bacterial origin. Together, our results demonstrated that DjTatD may be involved in the planarian immune response and pharyngeal regeneration. Furthermore, after further optimization in the future, rDjTatD and T7DjTatD can be considered highly effective antibiofilm agents.

11.
Nat Immunol ; 25(2): 307-315, 2024 Feb.
Article En | MEDLINE | ID: mdl-38182667

The global outbreak of the mpox virus (MPXV) in 2022 highlights the urgent need for safer and more accessible new-generation vaccines. Here, we used a structure-guided multi-antigen fusion strategy to design a 'two-in-one' immunogen based on the single-chain dimeric MPXV extracellular enveloped virus antigen A35 bivalently fused with the intracellular mature virus antigen M1, called DAM. DAM preserved the natural epitope configuration of both components and showed stronger A35-specific and M1-specific antibody responses and in vivo protective efficacy against vaccinia virus (VACV) compared to co-immunization strategies. The MPXV-specific neutralizing antibodies elicited by DAM were 28 times higher than those induced by live VACV vaccine. Aluminum-adjuvanted DAM vaccines protected mice from a lethal VACV challenge with a safety profile, and pilot-scale production confirmed the high yield and purity of DAM. Thus, our study provides innovative insights and an immunogen candidate for the development of alternative vaccines against MPXV and other orthopoxviruses.


Monkeypox virus , Vaccines , Animals , Mice , Viral Envelope Proteins , Antibodies, Viral , Vaccinia virus , Antigens, Viral , Immunity
13.
Sci Rep ; 14(1): 2197, 2024 01 25.
Article En | MEDLINE | ID: mdl-38273015

Type 2 diabetes with hyperuricaemia may lead to gout, kidney damage, hypertension, coronary heart disease, etc., further aggravating the condition of diabetes as well as adding to the medical and financial burden. To construct a risk model for hyperuricaemia in patients with type 2 diabetes mellitus based on artificial neural network, and to evaluate the effectiveness of the risk model to provide directions for the prevention and control of the disease in this population. From June to December 2022, 8243 patients with type 2 diabetes were recruited from six community service centers for questionnaire and physical examination. Secondly, the collected data were used to select suitable variables and based on the comparison results, logistic regression was used to screen the variable characteristics. Finally, three risk models for evaluating the risk of hyperuricaemia in type 2 diabetes mellitus were developed using an artificial neural network algorithm and evaluated for performance. A total of eleven factors affecting the development of hyperuricaemia in patients with type 2 diabetes mellitus in this study, including gender, waist circumference, diabetes medication use, diastolic blood pressure, γ-glutamyl transferase, blood urea nitrogen, triglycerides, low-density lipoprotein cholesterol, high-density lipoprotein cholesterol, fasting glucose and estimated glomerular filtration rate. Among the generated models, baseline & biochemical risk model had the best performance with cutoff, area under the curve, accuracy, recall, specificity, positive likelihood ratio, negative likelihood ratio, precision, negative predictive value, KAPPA and F1-score were 0.488, 0.744, 0.689, 0.625, 0.749, 2.489, 0.501, 0.697, 0.684, 0.375 and 0.659. In addition, its Brier score was 0.169 and the calibration curve also showed good agreement between fitting and observation. The constructed artificial neural network model has better efficacy and facilitates the reduction of the harm caused by type 2 diabetes mellitus combined with hyperuricaemia.


Diabetes Mellitus, Type 2 , Hyperuricemia , Humans , Risk Factors , Cholesterol, HDL , Neural Networks, Computer
14.
Chin Med J (Engl) ; 137(5): 588-595, 2024 Mar 05.
Article En | MEDLINE | ID: mdl-37415525

BACKGROUND: Cerebrovascular disease (CVD) ranks among the foremost factors responsible for mortality on a global scale. The mortality patterns of CVDs and temporal trends in China need to be well-illustrated and updated. METHODS: We collected mortality data on patients with CVD from Chinese Center for Disease Control and Prevention's Disease Surveillance Points (CDC-DSP) system. The mortality of CVD in 2020 was described by age, sex, residence, and region. The temporal trend from 2013 to 2019 was evaluated using joinpoint regression, and estimated rates of decline were extrapolated until 2030 using time series models. RESULTS: In 2019, the age-standardized mortality in China (ASMRC) per 100,000 individuals was 113.2. The ASMRC for males (137.7/10 5 ) and rural areas (123.0/10 5 ) were both higher when stratified by gender and urban/rural residence. The central region had the highest mortality (126.5/10 5 ), the western region had a slightly lower mortality (123.5/10 5 ), and the eastern region had the lowest mortality (97.3/10 5 ). The age-specific mortality showed an accelerated upward trend from aged 55-59 years, with maximum mortality observed in individuals over 85 years of age. The age-standardized mortality of CVD decreased by 2.43% (95% confidence interval, 1.02-3.81%) annually from 2013 to 2019. Notably, the age-specific mortality of CVD increased from 2013 to 2019 for the age group of over 85 years. In 2020, both the absolute number of CVD cases and the crude mortality of CVD have increased compared to their values in 2019. The estimated total deaths due to CVD were estimated to reach 2.3 million in 2025 and 2.4 million in 2030. CONCLUSION: The heightened focus on the burden of CVD among males, rural areas, the central and western of China, and individuals aged 75 years and above has emerged as a pivotal determinant in further decreasing mortalities, consequently presenting novel challenges to strategies for disease prevention and control.


Cardiovascular Diseases , Cerebrovascular Disorders , Male , Humans , Aged, 80 and over , Urban Population , Cardiovascular Diseases/epidemiology , China/epidemiology , Rural Population
15.
Comput Biol Med ; 168: 107715, 2024 01.
Article En | MEDLINE | ID: mdl-38007975

Sizing of flow diverters (FDs) is a challenging task in the treatment of intracranial aneurysms due to their foreshortening behavior. The purpose of this study is to evaluate the difference between the sizing results from the AneuGuide™ software and from conventional 2D measurement. Ninety-eight consecutive patients undergoing pipeline embolization device (PED) treatment between October 2018 and April 2023 in the First Medical Center of Chinese PLA General Hospital (Beijing, China) were retrospectively analyzed. For all cases, the optimal PED dimensions were both manually determined through 2D measurements on pre-treatment 3D-DSA and computed by AneuGuide™ software. The inter-rater reliability between the two sets of sizing results for each methodology was analyzed using intraclass correlation coefficient (ICC). The degree of agreement between manual sizing and software sizing were analyzed with the Bland-Altman plot and Pearson's test. Differences between two methodologies were analyzed with Wilcoxon signed rank test. Statistical significance was defined as p < 0.05. There was better inter-rater reliability between AneuGuide™ measurements both for diameter (ICC 0.92, 95%CI 0.88-0.95) and length (ICC 0.93, 95%CI 0.89-0.96). Bland-Altman plots showed a good agreement for diameter selection between two methodologies. However, the median length proposed by software group was significantly shorter (16 mm versus 20 mm, p < 0.001). No difference was found for median diameter (4.25 mm versus 4.25 mm). We demonstrated that the AneuGuide™ software provides highly reliable results of PED sizing compared with manual measurement, with a shorter stent length. AneuGuide™ may aid neurointerventionalists in selecting optimal dimensions for FD treatment.


Blood Vessel Prosthesis , Software , Humans , Retrospective Studies , Reproducibility of Results , Stents
16.
Int J Sports Med ; 45(2): 85-94, 2024 Feb.
Article En | MEDLINE | ID: mdl-37820692

To identify factors associated with subscapularis (SSC) tears and provide a theoretical basis for clinical diagnosis, we included studies related to subscapularis tears published before February 1, 2023. We screened for six predictors across previous studies for the meta-analysis. The predictors included age, sex, coracoid overlap (CO), coracohumeral distance (CHD), impairment of the long head of the biceps tendon (LHB), and dominant arm. The Newcastle-Ottawa Scale (NOS) was used to evaluate the quality of the studies. The risk ratios (RRs) and the weighted mean differences (WMDs) were used to evaluate the effect size of categorical variables and continuous variables, respectively. The Egger test was used to assess the publication bias of the studies. Ten studies were included from seven countries. A total of 2 126 patients were enrolled, of whom 1 041 had subscapularis tears and 1 085 did not. The study showed that age (WMD, 4.23 [95% CI, 2.32-6.15]; P<.00001), coracoid overlap (WMD, 1.98 [95% CI, 1.55-2.41]; P<.00001), coracohumeral distance(WMD, -1.03 [95% CI, -1.17- -0.88]; P<.00001), and an injury of the long head of the biceps tendon (RR, 4.98 [95% CI, 3.75-6.61]; P<.00001) were risk factors for subscapularis tears. These risk factors can help clinicians identify subscapularis tears early and select appropriate interventions. The level of evidence is 3.


Rotator Cuff Injuries , Rotator Cuff , Humans , Rotator Cuff Injuries/diagnosis , Retrospective Studies , Magnetic Resonance Imaging , Rupture , Arthroscopy
17.
Nano Lett ; 24(1): 16-25, 2024 Jan 10.
Article En | MEDLINE | ID: mdl-38109350

The anomalous Hall effect (AHE) is an important transport signature revealing topological properties of magnetic materials and their spin textures. Recently, MnBi2Te4 has been demonstrated to be an intrinsic magnetic topological insulator. However, the origin of its intriguing AHE behaviors remains elusive. Here, we demonstrate the Berry curvature-dominated intrinsic AHE in wafer-scale MnBi2Te4 films. By applying back-gate voltages, we observe an ambipolar conduction and n-p transition in ∼7-layer MnBi2Te4, where a quadratic relation between the AHE resistance and longitudinal resistance suggests its intrinsic AHE nature. In particular, for ∼3-layer MnBi2Te4, the AHE sign can be tuned from pristine negative to positive. First-principles calculations unveil that such an AHE reversal originated from the competing Berry curvature between oppositely polarized spin-minority-dominated surface states and spin-majority-dominated inner bands. Our results shed light on the underlying physical mechanism of the intrinsic AHE and provide new perspectives for the unconventional sign-tunable AHE.

18.
Opt Express ; 31(21): 35086-35099, 2023 Oct 09.
Article En | MEDLINE | ID: mdl-37859248

Metasurfaces have shown extraordinary capability in individually manipulating various electromagnetic (EM) properties, including polarization, phase, and amplitude. However, it is still a challenge to manipulate these EM properties in one metasurface simultaneously. In this paper, a programmable multifunctional metasurface (PMFMS) is demonstrated with polarization, phase, and amplitude manipulation abilities. By controlling tunable coding states and changing the direction of incident waves, the PMFMS can operate as a transmission cross-polarization converter, spatial wave manipulator, and low-RCS radome. Besides, the PMFMS possesses an ultra-wideband property, which can operate from 6.5 to 10.2 GHz with 44.3% relative bandwidth. More importantly, multiple functionalities can also be achieved in reflection operating mode by reassembling the PMFMS. As a proof of concept, the PMFMS is fabricated and experimentally verified. Measured results are in good agreement with simulated results. Benefiting from multifunctional EM manipulations in an ultra-wideband, such a design can be applied in wireless communication systems, radar detection, and EM stealth platform.

19.
Nano Lett ; 23(19): 9026-9033, 2023 Oct 11.
Article En | MEDLINE | ID: mdl-37767914

The quantum Hall effect is one of the exclusive properties displayed by Dirac Fermions in topological insulators, which propagates along the chiral edge state and gives rise to quantized electron transport. However, the quantum Hall effect formed by the nondegenerate Dirac surface states has been elusive so far. Here, we demonstrate the nondegenerate integer quantum Hall effect from the topological surface states in three-dimensional (3D) topological insulator ß-Ag2Te nanostructures. Surface-state dominant conductance renders quantum Hall conductance plateaus with a step of e2/h, along with typical thermopower behaviors of two-dimensional (2D) massless Dirac electrons. The 2D nature of the topological surface states is proven by the electrical and thermal transport responses under tilted magnetic fields. Moreover, the degeneracy of the surface states is removed by structure inversion asymmetry (SIA). The evidenced SIA-induced nondegenerate integer quantum Hall effect in low-symmetry ß-Ag2Te has implications for both fundamental study and the realization of topological magneto-electric effects.

20.
Stroke Vasc Neurol ; 2023 Jul 11.
Article En | MEDLINE | ID: mdl-37433695

OBJECTIVES: The presence of dural sinus septum has long been identified anatomically but is often neglected for its clinical significance. Our findings revealed the association of dural sinus septum with venous sinus stenting failure and complications supported by clinical evidence. METHODS: This retrospective study included 185 consecutive patients treated with cerebral venous sinus stenting from January 2009 to May 2022. We identified the dural sinus septa using digital subtraction angiography (DSA) and classified them into three types based on their location. The septa at the transverse sinus were defined as type I, those at the junction between the transverse sinus and sigmoid sinus were defined as type II and those at the sigmoid sinus were defined as type III. Based on the anatomic features and neuroimaging clues, we investigated the correlation of dural sinus septa with stenting failure and complications. RESULTS: 32 (17.1%) out of 185 patients (121 with idiopathic intracranial hypertension and 64 with venous pulsatile tinnitus) were identified with dural sinus septa by DSA. More than half of the septa were type I (18/32, 56.2%), followed by type II (11/32, 34.4%) and type III (3/32, 9.4%). The dural sinus septa caused three stenting failures and complications, including one case of venous sinus injury with subdural haemorrhage and two cases of incomplete stent expansion. Statistical analysis revealed that the presence of dural sinus septum (p<0.01) was associated with complications of cerebral venous sinus stenting. DISCUSSION: The dural sinus septum is a common structure in the cerebral venous sinus. We found that the presence of dural sinus septa introduces uncertainties to cerebral venous sinus stenting and suggested precautions and ingenious skills in imaging and treatment.

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