Distinguishable Magnetic Reporter Coordination with Buoyancy-Magnetism Separation for Immobilization-Free Dual-Target Electrochemical Immunosensing.

Simultaneous sensitive and precise determination of multibiomarkers is of great significance for improving detection efficiency, reducing diagnosis and treatment expenses, and elevating survival rates. However, the development of simple and portable biosensors for simultaneous determination of multiplexed targets in biological fluids still faces challenges. Herein, a unique and versatile immobilization-free dual-target electrochemical biosensing platform, which combines distinguishable magnetic signal reporters with buoyancy-magnetism separation, was designed and constructed for simultaneous detection of carcinoembryonic (CEA) and α-fetoprotein (AFP) in intricate biological fluids. To construct such distinguishable magnetic signal reporters with signal transduction, amplification, and output, secondary antibodies of CEA and AFP were respectively functionalized on methylene blue (MB) and 6-(ferrocenyl)hexanethiol (FeC) modified Fe3O4@Au magnetic nanocomposites. Meanwhile, a multifunctional flotation probe with dual target recognition, capture, and isolation capability was prepared by conjugating primary antibodies (Ab1-CEA, Ab1-AFP) to hollow buoyant microspheres. The target antigens of CEA and AFP can trigger a flotation-mediated sandwich-type immunoreaction and capture a certain amount of the distinguishable magnetic signal reporter, which enables the conversion of the target CEA and AFP quantities to the signal of the potential-resolved MB and FeC. Thus, the MB and FeC currents of magnetically adsorbed distinguishable magnetic reporters can be used to determine the CEA and AFP targets simultaneously and precisely. Accordingly, the proposed strategy exhibited a delightful linear response for CEA and AFP in the range of 100 fg·mL-1-100 ng·mL-1 with detection limits of 33.34 and 17.02 fg·mL-1 (S/N = 3), respectively. Meanwhile, no significant nonspecific adsorption and cross-talk were observed. The biosensing platform has shown satisfactory performance in the determination of real clinical samples. More importantly, the proposed approach can be conveniently extended to universal detection just by simply substituting biorecognition events. Thus, this work opens up a new promising perspective for dual and even multiple targets and offers promising potential applications in clinical diagnosis.

N-Heterocyclic Carbene-Derived 1,3,5-Trimethylenebenzene: On-Surface Synthesis and Electronic Structure.

1,3,5-Trimethylenebenzene (1,3,5-TMB), a 3-fold-symmetric triradical with a high-spin ground state, is an attractive platform for investigating the unique spin properties of π-conjugated triangular triradicals. Here, we report the on-surface synthesis of N-heterocyclic carbene (NHC)-derived 1,3,5-TMB (N-TMB) via surface-assisted C-C and C-N coupling reactions on Au(111). The chemical and electronic structures of N-TMB on the Au(111) surface are revealed with atomic precision using scanning tunneling microscopy and noncontact atomic force microscopy, combined with density functional theory (DFT) calculations. It is demonstrated that there is substantial charge transfer between N-TMB and the substrate, resulting in a positively charged N-TMB on Au(111). DFT calculations at the UB3LYP/def2-TZVP level of theory and multireference method, e.g., CASSCF/NEVPT2, indicate that N-TMB possesses a doublet ground state with reduced Cs symmetry in the gas phase, contrasting the quartet ground state of 1,3,5-TMB with D3h symmetry, and exhibits a doublet-quartet energy gap of -0.80 eV. The incorporation of NHC structures and the extended π-conjugation promote the spin-orbital overlaps in N-TMB, leading to Jahn-Teller distortion and the formation of a robust doublet state. Our results not only demonstrate the fabrication of polyradicals based on NHC but also shed light on the effect of NHC and π-conjugation on the electronic structure and spin coupling, which opens up new possibilities for precisely regulating the spin-spin exchange coupling of organic polyradicals.

Semiconservative transmission of DNA N6-adenine methylation in a unicellular eukaryote.

While DNA N6-adenine methylation (6mA) is best known in prokaryotes, its presence in eukaryotes has generated great interest recently. Biochemical and genetic evidence supports that AMT1, a MT-A70 family methyltransferase (MTase), is crucial for 6mA deposition in unicellular eukaryotes. Nonetheless, 6mA transmission mechanism remains to be elucidated. Taking advantage of Single Molecule Real-Time Circular Consensus Sequencing (SMRT CCS), here we provide definitive evidence for semiconservative transmission of 6mA in Tetrahymena thermophila In wild-type (WT) cells, 6mA occurs at the self-complementary ApT dinucleotide, mostly in full methylation (full-6mApT); after DNA replication, hemi-methylation (hemi-6mApT) is transiently present on the parental strand, opposite to the daughter strand readily labeled by 5-bromo-2'-deoxyuridine (BrdU). In ΔAMT1 cells, 6mA predominantly occurs as hemi-6mApT. Hemi-to-full conversion in WT cells is fast, robust, and processive, while de novo methylation in ΔAMT1 cells is slow and sporadic. In Tetrahymena, regularly spaced 6mA clusters coincide with linker DNA of nucleosomes arrayed in the gene body. Importantly, in vitro methylation of human chromatin by reconstituted AMT1 complex recapitulates preferential targeting of hemi-6mApT sites in linker DNA, supporting AMT1's intrinsic and autonomous role in maintenance methylation. We conclude that 6mA is transmitted by a semiconservative mechanism: full-6mApT is split by DNA replication into hemi-6mApT, which is restored to full-6mApT by AMT1-dependent maintenance methylation. Our study dissects AMT1-dependent maintenance methylation and AMT1-independent de novo methylation, reveals a 6mA transmission pathway with striking similarity to 5-methyl cytosine (5mC) transmission at the CpG dinucleotide, and establishes 6mA as a bona fide eukaryotic epigenetic mark.

A Prospective Self-controlled Clinical Trial of Nonactivated Low Leukocyte PRP in Female Pattern Hair Loss Patients of Childbearing Age.

BACKGROUND: Alopecia significantly affects the mental health and social relationship of women since childbearing age, highlighting the need for a safe, effective, and convenient treatment. METHODS: The authors have conducted a prospective self-controlled trial involving 15 female patients at childbearing age with alopecia. These patients received a subcutaneous scalp injection of platelet-rich plasma once every 4 weeks for 3 treatments in total. Outcome measurements were included below: changes in hair density (hair/cm2), hair follicle density (hair follicle/cm2), and overall photographic assessment (improved or not) at 4, 12, and 24 weeks right after the first treatment. RESULTS: Comparing the photographs taken before and after the intervention, 67% of patients' hair density increased from 151 ± 39.82 hairs/cm2 (preintervention) to 170.96 ± 37.14 hairs/cm2 (at 24-week follow-up), representing an approximate increase of 19 hairs/cm2. Meanwhile, hair follicle density increased by approximately 15 follicles/cm2 after 24 weeks since the first treatment, rising from 151.04 ± 41.99 follicles/cm2 to 166.72 ± 37.13 follicles/cm2. The primary adverse reactions observed were local swelling and pain due to injections. CONCLUSION: Local injection of nonactivated platelet-rich plasma with low leukocytes concentration could be an effective strategy to alleviate alopecia symptoms in female patients.

Constructing an Asymmetric Covalent Triazine Framework to Boost the Efficiency and Selectivity of Visible-Light-Driven CO2 Photoreduction.

The photocatalytic reduction of CO2 represents an environmentally friendly and sustainable approach for generating valuable chemicals. In this study, a thiophene-modified highly conjugated asymmetric covalent triazine framework (As-CTF-S) is developed for this purpose. Significantly, single-component intramolecular energy transfer can enhance the photogenerated charge separation, leading to the efficient conversion of CO2 to CO during photocatalysis. As a result, without the need for additional photosensitizers or organic sacrificial agents, As-CTF-S demonstrates the highest photocatalytic ability of 353.2 µmol g-1 and achieves a selectivity of ≈99.95% within a 4 h period under visible light irradiation. This study provides molecular insights into the rational control of charge transfer pathways for high-efficiency CO2 photoreduction using single-component organic semiconductor catalysts.

Biomimetic Frustrated Lewis Pair Catalysts for Hydrogenation of CO to Methanol at Low Temperatures.

The industrial production of methanol through CO hydrogenation using the Cu/ZnO/Al2O3 catalyst requires harsh conditions, and the development of new catalysts with low operating temperatures is highly desirable. In this study, organic biomimetic FLP catalysts with good tolerance to CO poison are theoretically designed. The base-free catalytic reaction contains the 1,1-addition of CO into a formic acid intermediate and the hydrogenation of the formic acid intermediate into methanol. Low-energy spans (25.6, 22.1, and 20.6 kcal/mol) are achieved, indicating that CO can be hydrogenated into methanol at low temperatures. The new extended aromatization-dearomatization effect involving multiple rings is proposed to effectively facilitate the rate-determining CO 1,1-addition step, and a new CO activation model is proposed for organic catalysts.

Secondary metabolites in host pears defense against two fruit borers and cytochrome-P450-mediated counter-defense.

Herbivorous insects have evolved metabolic strategies to survive the challenges posed by plant secondary metabolites (SMs). This study reports an exploration of SMs present in pears, which serve as a defense against invasive Cydia pomonella and native Grapholita molesta and their counter-defense response. The feeding preferences of fruit borers are influenced by the softening of two pear varieties as they ripen. The content of SMs, such as quercetin and rutin, increases due to feeding by fruit borers. Notably, quercetin levels only increase after C. pomonella feeding. The consumption of SMs affects the growth of fruit borer population differently, potentially due to the activation of P450 genes by SMs. These two fruit borers are equipped with specific P450 enzymes that specialize in metabolizing quercetin and rutin, enabling them to adapt to these SMs in their host fruits. These findings provide valuable insights into the coevolution of plants and herbivorous insects.

Indomethacin restrains cytoplasmic nucleic acid-stimulated immune responses by inhibiting the nuclear translocation of IRF3.

The recognition of cytosolic nucleic acid triggers the DNA/RNA sensor-IRF3 axis-mediated production of type I interferons (IFNs), which are essential for antiviral immune responses. However, the inappropriate activation of these signaling pathways is implicated in autoimmune conditions. Here, we report that indomethacin, a widely used nonsteroidal anti-inflammatory drug, inhibits nucleic acid-triggered IFN production. We found that both DNA- and RNA-stimulated IFN expression can be effectively blocked by indomethacin. Interestingly, indomethacin also prohibits the nuclear translocation of IRF3 following cytosolic nucleic acid recognition. Importantly, in cell lines and a mouse model of Aicardi-Goutières syndrome, indomethacin administration blunts self-DNA-induced autoimmune responses. Thus, our study reveals a previously unknown function of indomethacin and provides a potential treatment for cytosolic nucleic acid-stimulated autoimmunity.

Quantum spin driven Yu-Shiba-Rusinov multiplets and fermion-parity-preserving phase transition in K3C60.

Magnetic impurities in superconductors are of increasing interest due to emergent Yu-Shiba-Rusinov (YSR) states and Majorana zero modes for fault-tolerant quantum computation. However, a direct relationship between the YSR multiple states and magnetic anisotropy splitting of quantum impurity spins remains poorly characterized. By using scanning tunneling microscopy, we systematically resolve individual transition-metal (Fe, Cr, and Ni) impurities induced YSR multiplets as well as their Zeeman effects in the K3C60 superconductor. The YSR multiplets show identical d orbital-like wave functions that are symmetry-mismatched to the threefold K3C60(1 1 1) host surface, breaking point-group symmetries of the spatial distribution of YSR bound states in real space. Remarkably, we identify an unprecedented fermion-parity-preserving quantum phase transition between ground states with opposite signs of the uniaxial magnetic anisotropy that can be manipulated by an external magnetic field. These findings can be readily understood in terms of anisotropy splitting of quantum impurity spins, and thus elucidate the intricate interplay between the magnetic anisotropy and YSR multiplets.

Efficacy and safety of precision-guided transjugular extrahepatic portosystemic shunt (TEPS) in the management of cavernous transformation of the portal vein with portal hypertension: a case series.

BACKGROUND AND AIMS: Performing a Transjugular intrahepatic portal system shunt (TIPS) in patients with portal vein cavernous transformation (CTPV) poses significant challenges. As an alternative, transjugular extrahepatic portal vein shunt (TEPS) may offer a potential solution for these patients. Nonetheless, the effectiveness and safety of TEPS remain uncertain. This case series study aimed to evaluate the efficacy and safety of TEPS in treating patients with CTPV portal hypertension complications. METHODS: The study encompassed a cohort of 22 patients diagnosed with CTPV who underwent TEPS procedures. Of these, 13 patients manifested recurrent hemorrhagic episodes subsequent to conventional therapies, 8 patients grappled with recurrent or refractory ascites, and 1 patient experienced acute bleeding but refused endoscopic treatment. Comprehensive postoperative monitoring was conducted for all patients to rigorously evaluate both the technical and clinical efficacy of the intervention, as well as long-term outcomes. RESULTS: The overall procedural success rate among the 22 patients was 95.5% (21/22).During the TEPS procedure, nine patients were guided by percutaneous splenic access, three patients were guided by percutaneous hepatic access, five patients were guided by transmesenteric vein access from the abdomen, and two patients were guided by catheter marking from the hepatic artery. Additionally, guidance for three patients was facilitated by pre-existing TIPS stents. The postoperative portal pressure gradient following TEPS demonstrated a statistically significant decrease compared to preoperative values (24.95 ± 3.19 mmHg vs. 11.48 ± 1.74 mmHg, p < 0.01).Although three patients encountered perioperative complications, their conditions ameliorated following symptomatic treatment, and no procedure-related fatalities occurred. During a median follow-up period of 14 months, spanning a range of 5 to 39 months, we observed four fatalities. Specifically, one death was attributed to hepatocellular carcinoma, while the remaining three were ascribed to chronic liver failure. During the follow-up period, no instances of shunt dysfunction were observed. CONCLUSIONS: Precision-guided TEPS appears to be a safe and efficacious intervention for the management of CTPV.

2,2'-Bipyridine-Enabled Photocatalytic Radical [4+2] Cyclization of N-Aryl-α-amino Acids for Synthesizing Polysubstituted Tetrahydroquinolines.

A facile photocatalytic radical [4+2] cyclization of N-aryl-α-amino acids with various alkenes to access structurally polysubstituted tetrahydroquinolines has been developed. Using a simple bipyridine as a catalyst, different N-aryl-α-amino acids could be utilized as the radical precursors to react with diverse electrophilic alkenes, including exocyclic terminal alkenes, acyclic terminal alkenes, and cycloalkenes, producing 10 types of nitrogen-containing heterocyclic compounds fused in multiple frameworks in generally moderate yields with good diastereoselectivities. Scale-up synthesis and transformations of the products further demonstrated the synthetic application of this protocol. Moreover, a decarboxylative radial pathway via a proton-coupled electron transfer process for illustration of this [4+2] cyclization was proposed on the basis of the control experiments. This process is highlighted by a simple bipyridine photocatalysis, mild reaction conditions, various N-aryl-α-amino acids and alkene materials, and application for the modification of natural products.

Iron(II)-Catalyzed Radical [3 + 2] Cyclization of N-Aryl Cyclopropylamines for the Synthesis of Polyfunctionalized Cyclopentylamines.

A facile iron(II)-catalyzed radical [3 + 2] cyclization of N-aryl cyclopropylamines with various alkenes to access the structurally polyfunctionalized cyclopentylamine scaffolds has been developed. Using low-cost FeCl2·4H2O as catalyst, N-aryl cyclopropylamines could be utilized to react with a wide range of alkenes including exocyclic/acyclic terminal alkenes, cycloalkenes, alkenes from the natural-occurring compounds (Alantolactone, Costunolide), and known drugs (Ibuprofen, l-phenylalanine, Flurbiprofen) to obtain a variety of cyclopentylamines fused with different useful motifs in generally good yields and diastereoselectivities. The highlight of this protocol is also featured by no extra oxidant, no base, EtOH as the solvent, gram-scale synthesis, and further diverse transformations of the synthetic products. More importantly, an iron(II)-mediated hydrogen radical dissociation pathway was proposed based on the mechanism research experiments.

Silver Surface-Assisted Dehydrobrominative Cross-Coupling between Identical Aryl Bromides.

Cross-coupling reactions represent an indispensable tool in chemical synthesis. An intriguing challenge in this field is to achieve selective cross-coupling between two precursors with similar reactivity or, to the limit, the identical molecules. Here we report an unexpected dehydrobrominative cross-coupling between 1,3,5-tris(2-bromophenyl)benzene molecules on silver surfaces. Using scanning tunneling microscopy, we examine the reaction process at the single-molecular level, quantify the selectivity of the dehydrobrominative cross-coupling, and reveal the modulation of selectivity by substrate lattice-related catalytic activity or molecular assembly effect. Theoretical calculations indicate that the dehydrobrominative cross-coupling proceeds via regioselective C-H bond activation of debrominated TBPB and subsequent highly selective C-C coupling of the radical-based intermediates. The reaction kinetics plays an important role in the selectivity for the cross-coupling. This work not only expands the toolbox for chemical synthesis but also provides important mechanistic insights into the selectivity of coupling reactions on the surface.

Gossamer: Scaling Image Processing and Reconstruction to Whole Brains.

Neuronal reconstruction-a process that transforms image volumes into 3D geometries and skeletons of cells-bottlenecks the study of brain function, connectomics and pathology. Unlike artistic domains with similar challenges (e.g., hair modeling), scientists need exact and complete segmentations to study subtle topological differences. Existing methods are disk-bound, dense-access, coupled, single-threaded, algorithmically unscalable and require manual cropping of small windows and proofreading of skeletons due to low topological accuracy. Designing a data-intensive parallel solution suited to a neurons' shape, topology and far-ranging connectivity is particularly challenging due to I/O and load-balance, yet by abstracting vision tasks such as segmentation and skeletonization into strategically ordered specializations of search, we progressively lower memory by 4 orders of magnitude. This enables 1 mouse brain to be fully processed in-memory on a single server, at 67× the scale with 870× less memory while having 78% higher automated yield than the highest performing alternative methods.

Gemfibrozil-Platinum(IV) Precursors for New Enhanced-Starvation and Chemotherapy In Vitro and In Vivo.

A brand-new enhanced starvation is put forward to trigger sensitized chemotherapy: blocking tumor-relation blood vessel formation and accelerating nutrient degradation and efflux. Following this concept, two cisplatin-like gemfibrozil-derived Pt(IV) prodrugs, GP and GPG, are synthesized. GP and GPG had nanomolar IC50 against A2780 cells and higher selectivity against normal cells than cisplatin. Bioactivity results confirmed that GP and GPG highly accumulated in cells and induced DNA damage, G2-phase arrest, and p53 expression. Besides, they could increase ROS and MDA levels and reduce mitochondrial membrane potential and Bcl-2 expression to promote cell apoptosis. In vivo, GP showed superior antitumor activity in A2780 tumor-bearing mice with no observable tissue damage. Mechanistic studies suggested that highly selective chemotherapy could be due to the new enhanced starvation effect: blocking vasculature formation via inhibiting the CYP2C8/EETs pathway and VEGFR2, NF-κB, and COX-2 expression and cholesterol efflux and degradation acceleration via increasing ABCA1 and PPARα.

Secular trends in the prevalence of meeting 24-hour movement guidelines among U.S. adolescents: evidence from NHANES 2007-2016.

Background: The 24-Hour Movement Guidelines (24-HMG) recommend a balanced combination of physical activity (PA), sedentary behavior (SB) and sleep (SLP) for optimal health. However, there is limited understanding of how well U.S. adolescents adhere to these guidelines. This study aims to analyze the prevalence trends of meeting the 24-HMG among a nationally representative sample of U.S. general adolescents. Methods: The study included 2,273 adolescents (55.3% boys) aged 16-19 who participated in the National Health and Nutrition Examination Surveys (NHANES) from 2007 to 2016. The researchers categorized the adolescents based on whether they met various PA, SB, and SLP recommendations, as well as different combinations of these recommendations, separately for boys and girls. The prevalence rate, weighted by survey data, was calculated along with a 95% confidence interval (CI) to assess the changes in meeting the 24-HMG among U.S. adolescents across different survey years and sociodemographic subgroups. Results: In the 2015-2016 cycle, approximately 6.3% of adolescents did not meet any of the three recommendations, while only 19.2% of adolescents achieved all three guidelines. Compliance with PA and SB recommendations among adolescents has decreased over time, from 72.5% (65.9% to 79.2%) to 64.2% (57.4% to 70.9%) for PA, and from 59.0% (49.6% to 68.4%) to 46.6% (37.8% to 55.5%) for SB, respectively, from 2007-2008 cycle to 2015-2016 cycle. Boys exhibited more favorable patterns in meeting different sets of recommendations compared to girls (p-value <0.001). This includes meeting both PA and SB guidelines (15.5% for boys and 11.1% for girls) and meeting both PA and SLP guidelines (19.5% for boys and 15.7% for girls). The level of parental education was found to have effect on meeting all three guidelines (Ptrend < 0.05). Conclusion: We analyzed ten consecutive years of representative NHANES data to evaluate the prevalence meeting 24-HMG and found that the proportion of adolescents aged 16-19 in the U.S. who adhered to all three movement guidelines simultaneously has consistently remained low throughout each survey cycle. Notably, there has been a significant decline in the proportion of adolescents meeting the SB guideline.

Preventing CXCL12 elevation helps to reduce acute exacerbation of COPD in individuals co-existing type-2 diabetes: A bioinformatics and clinical pharmacology study.

AIMS: To investigate the immunology shared mechanisms underlying chronic obstructive pulmonary disease (COPD) and type 2 diabetes mellitus (T2DM) and examine the impact of anti-diabetic drugs on acute exacerbation of COPD (AECOPD). METHODS: We analyzed GSE76925, GSE76894, GSE37768, and GSE25724 to identify differentially expressed genes. Hub-genes were identified through protein-protein interaction network analysis and evaluated by the receiver operating characteristic curve. CXCL12 emerged as a robust biomarker, and its correlation with lung function and CD8+ T cells were further quantified and validated. The activated signaling pathways were inferred through Gene set enrichment analysis (GSEA). The retrospective clinical analysis was executed to identify the influence of dipeptidyl peptidase-4 inhibitors (DPP-4i) on CXCL12 and evaluate the drug's efficacy in AECOPD. RESULTS: The significant up-regulation of CXCL12 expression in patients with two diseases were revealed. CXCL12 exhibited a negative correlation with pulmonary function (r = -0.551, p < 0.05). Consistent with analysis in GSE76925 and GSE76894, the positive correlation between the proportion of CD8+ T cells was demonstrated(r=0.469, p<0.05). GSEA identified "cytokines interaction" as an activated signaling pathway, and the clinical study revealed the correlation between CXCL12 and IL-6 (r=0.668, p<0.05). In patients with COPD and T2DM, DDP-4i treatment exhibited significantly higher serum CXCL12, compared to GLP-1RA. Analysis of 187 COPD patients with T2DM indicated that the DPP-4i group had a higher frequency of AECOPD compared to the GLP-1RA group (OR 1.287, 95%CI [1.018-2.136]). CONCLUSIONS: CXCL12 may represent a therapeutic target for COPD and T2DM. GLP-1RA treatment may be associated with lower CXCL12 levels and a lower risk of AECOPD compared to DPP-4i treatment. CLINICAL TRIAL REGISTRATION: China Clinical Trial Registration Center（ChiCTR2200055611）.

Dual-potential ratiometric electrochemiluminescence based on single emitter and single coreactant for the sensitive detection of carcinoembryonic antigen.

Dual-potential ratiometric electrochemiluminescence (ECL) is in favor of resistance to environmental interference. However, two kinds of emitters or coreactants, and a wide scan potential range (>2 V) are mandatory. This work developed a new dual-potential ratiometric ECL sensor for detection of carcinoembryonic antigen (CEA) using single emitter (luminol) and single coreactant (H2O2) with a mild potential range from -0.1 to 0.6 V. Luminol could produce a strong cathodic ECL (Ec) induced by hydroxyl radicals (HO‧) from the reduction of H2O2, and a relatively weak anodic ECL (Ea). After the ferrocene modified CEA aptamer (Apt-Fc) was attached, Fc could promote Ea by catalyzing the oxidation of H2O2, and reduce Ec by consuming HO‧. With the cycling amplification of the exonuclease I, CEA could substantially reduce the amount of Apt-Fc, resulting in the decrease of Ea and the rise of Ec. So, the ratio of Ec to Ea (Ec/Ea) was used as the detection signal, realizing the sensitive determination of CEA from 0.1 pg mL-1 to 10 ng mL-1 with a LOD of 41.85 fg mL-1 (S/N = 3). The developed sensor demonstrated excellent specificity, stability and reproducibility, with satisfactory results in practical detection.

Improved empirical mode decomposition method based on amplitude-frequency characteristic of vortex signals.

The vortex flowmeter occupies a vital position in flow measurement with its unique advantages. It is essentially a fluid vibration instrument, and its measurement process is susceptible to interference, which seriously affects measurement accuracy. In particular, at low flow rates, it is an urgent problem to extract vortex signals from the complex noise. Among many signal processing methods, Empirical Mode Decomposition (EMD) is a time-frequency analysis method suitable for nonlinear, non-stationary signals. EMD can adaptively decompose noisy signals into noise and useful signal components arranged from high frequency to low frequency. For the above problems, an innovative, improved EMD method is proposed in this paper. The digital filter is designed according to the amplitude-frequency characteristic of vortex signals. After filtering, the vortex signal is adjusted to a fixed value, and high-frequency noise is filtered. According to the consistency of the filtered signal's amplitude, we design a decomposition stop criterion for EMD to process the output signal of the vortex sensor. This method not only maintains the characteristic of adaptive decomposition in EMD but also completes the automatic extraction of the vortex signal under complex noise. It provides a new comprehensive method for realizing high-precision and anti-interference vortex flowmeters.

Relative apical sparing obtained with speckle tracking echocardiography is not a sensitive parameter for diagnosing light-chain cardiac amyloidosis.

Background: Distinguishing light-chain cardiac amyloidosis (AL CA) from left ventricular wall thickening (LVWT) resulted from other etiologies has proven to be challenging. This study aimed to determine the sensitivity and specificity of relative apical sparing in diagnosing AL CA and investigate the differences in clinical and echocardiographic characteristics between AL CA patients with apical sparing and those with non-apical sparing. Methods: A total of 63 consecutive patients with AL CA, 102 consecutive patients with LVWT (including 51 hypertrophic cardiomyopathy (HCM) and 51 hypertension) and 33 healthy individuals were recruited retrospectively at Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology. Conventional and speckle tracking echocardiography were performed on all subjects. Results: Although wall thickening was observed in all patients, almost all functional parameters were worse in AL CA, except for relative apical longitudinal strain (LS) (P=0.906). Of 63 patients with AL CA, only 17.5% (n=11) showed an apical sparing pattern. Patients with apical sparing had poorer cardiac performance than those with non-apical sparing. Relative apical sparing showed the lowest diagnostic accuracy with an area under the curve (AUC) of 0.58 [95% confidence interval (CI): 0.49-0.67, sensitivity: 17.5%, specificity: 98.0%, P=0.095] to detect AL CA, but right ventricular strain (RVS) (AUC: 0.86, P<0.001) showed the highest among all echocardiographic parameters. When diagnosing AL CA patients with non-apical sparing, RVS continued to maintain excellent diagnostic accuracy (AUC: 0.84, P<0.001), followed by left atrial reservoir strain (LASr) (AUC: 0.77, P<0.001). Conclusions: The diagnostic value of relative apical sparing for AL CA was limited with low sensitivity. In clinical practice, the diagnosis of early AL CA patients should not solely rely on relative apical sparing.