28 research outputs found

    Self-Assembled DNA Hydrogel as Switchable Material for Aptamer-Based Fluorescent Detection of Protein

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    The methodology based on target-responsive structural switching is powerful in bioanalysis with the controllability and sensitivity. In this paper, an aptamer-functionalized DNA hydrogel was designed as a specifically target-responsive switchable material for protein detection. This pure DNA hydrogel was constructed by using a Y-shaped DNA and an aptamer linker through a DNA self-assembly without synthetic polymer backbone. With use of thrombin as the model analyte, the DNA hydrogel was first applied to visual detection with the entrapped Au nanoparticles (AuNPs) as indicating agent. Furthermore, the positively charged quantum dots (QDs) as the fluorophore were synthesized by using polyethyleneimine (PEI) as wrapper and characterized with spectroscopy, transmission electron micrograph, ζ potential, and dynamic laser scattering techniques. Along with a gel-to-sol transition in the presence of the target, the released negatively charged AuNPs from the hydrogel could approach the positively charged QDs. Due to the electrostatic interaction, fluorescence resonance energy transfer between PEI-QDs and AuNPs therefore occurred and quenched the fluorescence signal for the sensitive detection of thrombin. This assay for the detection of thrombin showed a good linear relationship in a range of 0.075 to 12.5 μM with a detection limit of 67 nM at 3σ, and demonstrated excellent feasibility in complex serum matrixes. The biocompatible DNA hydrogel provides a universal switchable material for signal transduction and significantly demonstrates proof-of-concept for the detection of proteins

    Additional file 1 of Prevalence, awareness and control of type 2 diabetes mellitus and risk factors in Chinese elderly population

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    Additional file 1: Table 1. Sociodemographic characteristics of adults aged 65 and older in Wuhan. Notes: T2DM, type 2 diabetes mellitus; SD, standard deviation; BMI, body mass index; SBP, systolic blood pressure; DBP, diastolic blood pressure; WC, waist circumference; FBG, fasting plasma glucose. * P < 0.05;** P < 0.01;***P < 0.001; Categorical variables were analyzed by chi-square test

    Additional file 3 of Prevalence, awareness and control of type 2 diabetes mellitus and risk factors in Chinese elderly population

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    Additional file 3: Table 3. Risk factors for the prevalence, awareness, and control of T2DM. Notes: T2DM, type 2 diabetes mellitus; OR, odds ratio; CI, confidence interval; BMI, body mass index. a Multivariate logistic analysis. Model fittings were conducted using stepwise method with a threshold of 0.10 for variable inclusion in the model. b Central obesity was defined as waist circumference 90 cm or more in men and 85 cm or more in women. * P < 0.05;** P < 0.01;***P < 0.001; Variables that were not included in the final logistic regression model were marked with “-”

    Additional file 2 of Prevalence, awareness and control of type 2 diabetes mellitus and risk factors in Chinese elderly population

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    Additional file 2: Table 2. Prevalence, awareness, and control of T2DM among adults aged 65 and older in Wuhan. Notes: T2DM, type 2 diabetes mellitus; CI, confidence interval; BMI, body mass index. a Central obesity was defined as waist circumference 90 cm or more in men and 85 cm or more in women. * P < 0.05;** P < 0.01;***P < 0.001; Categorical variables were analyzed by chi-square test

    All-Graphene Three-Terminal-Junction Field-Effect Devices as Rectifiers and Inverters

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    We present prominent tunable and switchable room-temperature rectification performed at 100 kHz ac input utilizing micrometer-scale three-terminal junction field-effect devices. Monolayer CVD graphene is used as both a channel and a gate electrode to achieve all-graphene thin-film structure. Instead of ballistic theory, we explain the rectification characteristics through an electric-field capacitive model based on self-gating in the high source–drain bias regime. Previously, nanoscale graphene three-terminal junctions with the ballistic (or quasi-ballistic) operation have shown rectifications with relatively low efficiency. Compared to strict nanoscale requirements of ballistic devices, diffusive operation gives more freedom in design and fabrication, which we have exploited in the cascading device architecture. This is a significant step for all-graphene thin-film devices for integrated monolithic graphene circuits

    Ultrafast Synthesis of Layered Transition-Metal Oxide Cathodes from Metal–Organic Frameworks for High-Capacity Sodium-Ion Batteries

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    Layered transition-metal oxides are promising candidate cathode materials for sodium-ion batteries due to their abundant raw materials and high theoretical capacity. Nevertheless, a long-time high-temperature heat treatment is required in traditional preparation methods, leading to low synthesis efficiency and waste of energy. Herein, an ultrafast preparation method of layered transition-metal oxides was proposed through minute calcination of metal–organic frameworks (MOFs). The homogeneous distribution of different atoms in MOFs allows fast phase transition during the calcination process. P′2-phase layered sodium manganese oxide was successfully obtained and demonstrated excellent electrochemical performance, with a high reversible capacity of 212 mA h g–1 and a cycling performance of 84% capacity retention after 100 cycles. Furthermore, this method can be expanded to a wide variety of MOF precursors and oxide electrode materials for different types of batteries. Our findings provide an efficient and cost-effective synthesis method for high-performance layered transition-metal oxide cathodes

    Grain Refinement of Al-5Ti-0.62C-0.2Nd Grain Refiner for Commercial Pure Aluminum and Its Effect on Mechanical Properties

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    It is well known that the mechanical properties of commercial pure Al are influenced by size of α-Al dendrites. In the present work, Al-5Ti-0.62C-0.2Nd grain refiner was prepared by a pure molten aluminum thermal explosion reaction, and its effect on grain refinement and mechanical properties of commercial pure Al was investigated. Microstructure and phase composition show that Al-5Ti-0.62C-0.2Nd grain refiner consists of α-Al, granular TiC, lump-like TiAl3, and block-like Ti2Al20Nd. Grain-refining tests on commercial pure Al show that an Al-5Ti-0.62C-0.2Nd grain refiner has better refining performance compared with Al-5Ti-0.62C grain refiner. With addition of 0.2-wt.%-Al-5Ti-0.62C-0.2Nd grain refiner, the average grain size of commercial pure Al can be refined from roughly 2800 to 155±5 µm effectively, and it has higher resistance to grain-refinement fading. On account of the grain refinement, the tensile strength and elongation are increased by approximately 18.3% and 83.5%, respectively.</div

    DataSheet_1_A radiomics model based on preoperative gadoxetic acid–enhanced magnetic resonance imaging for predicting post-hepatectomy liver failure in patients with hepatocellular carcinoma.docx

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    BackgroundPost-hepatectomy liver failure (PHLF) is a fatal complication after liver resection in patients with hepatocellular carcinoma (HCC). It is of clinical importance to estimate the risk of PHLF preoperatively.AimsThis study aimed to develop and validate a prediction model based on preoperative gadoxetic acid–enhanced magnetic resonance imaging to estimate the risk of PHLF in patients with HCC.MethodsA total of 276 patients were retrospectively included and randomly divided into training and test cohorts (194:82). Clinicopathological variables were assessed to identify significant indicators for PHLF prediction. Radiomics features were extracted from the normal liver parenchyma at the hepatobiliary phase and the reproducible, robust and non-redundant ones were filtered for modeling. Prediction models were developed using clinicopathological variables (Clin-model), radiomics features (Rad-model), and their combination.ResultsThe PHLF incidence rate was 24% in the whole cohort. The combined model, consisting of albumin–bilirubin (ALBI) score, indocyanine green retention test at 15 min (ICG-R15), and Rad-score (derived from 16 radiomics features) outperformed the Clin-model and the Rad-model. It yielded an area under the receiver operating characteristic curve (AUC) of 0.84 (95% confidence interval (CI): 0.77–0.90) in the training cohort and 0.82 (95% CI: 0.72–0.91) in the test cohort. The model demonstrated a good consistency by the Hosmer–Lemeshow test and the calibration curve. The combined model was visualized as a nomogram for estimating individual risk of PHLF.ConclusionA model combining clinicopathological risk factors and radiomics signature can be applied to identify patients with high risk of PHLF and serve as a decision aid when planning surgery treatment in patients with HCC.</p

    DataSheet_1_A Radiomics Model Based on Gd-EOB-DTPA-Enhanced MRI for the Prediction of Microvascular Invasion in Solitary Hepatocellular Carcinoma ≤ 5 cm.docx

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    AimThe aim of this study is to establish and validate a radiomics-based model using preoperative Gd-EOB-DTPA-enhanced MRI to predict microvascular invasion (MVI) in patients with hepatocellular carcinoma ≤ 5 cm.MethodsClinicopathologic and MRI data of 178 patients with solitary hepatocellular carcinoma (HCC) (≤5 cm) were retrospectively collected from a single medical center between May 2017 and November 2020. Patients were randomly assigned into training and test subsets by a ratio of 7:3. Imaging features were extracted from the segmented tumor volume of interest with 1-cm expansion on arterial phase (AP) and hepatobiliary phase (HBP) images. Different models based on the significant clinical risk factors and/or selected imaging features were established and the predictive performance of the models was evaluated.ResultsThree radiomics models, the AP_model, the HBP_model, and the AP+HBP_model, were constructed for MVI prediction. Among them, the AP+HBP_model outperformed the other two. When it was combined with a clinical model, consisting of tumor size and alpha-fetoprotein (AFP), the combined model (AP+HBP+Clin_model) showed an area under the curve of 0.90 and 0.70 in the training and test subsets, respectively. Its sensitivity and specificity were 0.91 and 0.76 in the training subset and 0.60 and 0.79 in the test subset, respectively. The calibration curve illustrated that the combined model possessed a good agreement between the predicted and the actual probabilities.ConclusionsThe radiomics-based model combining imaging features from the arterial and hepatobiliary phases of Gd-EOB-DTPA-enhanced MRI and clinical risk factors provides an effective and reliable tool for the preoperative prediction of MVI in patients with HCC ≤ 5 cm.</p
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