The k-modes clustering algorithm has been widely used to cluster categorical data. In this paper, we firstly analyzed the k-modes algorithm and its dissimilarity measure. Based on this, we then ...proposed a novel dissimilarity measure, which is named as GRD. GRD considers not only the relationships between the object and all cluster modes but also the differences of different attributes. Finally the experiments were made on four real data sets from UCI. And the corresponding results show that GRD achieves better performance than two existing dissimilarity measures used in k-modes and Cao’s algorithms.
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FZAB, GIS, IJS, IZUM, KILJ, NLZOH, NUK, OILJ, PILJ, PNG, SAZU, SBCE, SBMB, UL, UM, UPUK
The catalytic deoxygenation mechanism of fatty acid esters on a Lewis acid site of ZSM-5 zeolite was elucidated via density functional theory (DFT) by using a methyl butyrate (MB) as the model ...compound for fatty acid esters. The configurations of the initial reactant, transition states, and products together with the activation barrier of each elementary reaction were determined. The activation barrier of different initial cracking reactions decreases in the order of α-C–C > β-C–C > α-C–O > β-C–O. The best reaction path for catalytic deoxygenation of methyl butyrate over Lewis acid site is CH3CH2CH2C(OCH3)=O⋯Lewis → CH3CH2⋯Lewis⋯C(=CH2)OCH3 → CH2=CH2 + CH3COOCH3 + Lewis. The oxygen of methyl butyrate is mainly removed as CO2, methyl acetate, formaldehyde, and butyraldehyde, while ethylene, propylene, and butane are the main hydrocarbon products. In addition, the group generated by cracking of methyl butyrate form a bond with the Lewis acid site, promoting the transformation between a Lewis acid and a Brønsted acid. The corresponding intermediates have a high single point energy, but the poor stability leads to further deoxygenation and cracking reactions. This work provides a theoretical basis for the modification in the number of Brønsted acid and Lewis acid sites in the ZSM-5 zeolite.
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IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
Chimeric antigen receptor T cell (CART) therapy is currently one of the most promising treatment approaches in cancer immunotherapy. However, the immunosuppressive nature of the tumor ...microenvironment, in particular increased reactive oxygen species (ROS) levels, provides considerable limitations. In this study, we aimed to exploit increased ROS levels in the tumor microenvironment with prodrugs of ROS accelerators, which are specifically activated in cancer cells. Upon activation, ROS accelerators induce further generation of ROS. This leads to an accumulation of ROS in tumor cells. We hypothesized that the latter cells will be more susceptible to CARTs. CD19-specific CARTs were generated with a CD19.CAR.CD28.CD137zeta third-generation retroviral vector. Cytotoxicity was determined by chromium-51 release assay. Influence of the ROS accelerators on viability and phenotype of CARTs was determined by flow cytometry. The combination of CARTs with the ROS accelerator PipFcB significantly increased their cytotoxicity in the Burkitt lymphoma cell lines Raji and Daudi, as well as primary chronic lymphocytic leukemia cells. Exposure of CARTs to PipFcB for 48 h did not influence T cell exhaustion, viability, or T cell subpopulations. In summary, the combination of CARTs with ROS accelerators may improve adoptive immunotherapy and help to overcome tumor microenvironment-mediated treatment resistance.
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IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
Carcinoembryonic antigen (CEACAM5), as a broad-spectrum tumor biomarker, plays a crucial role in analyzing the therapeutic efficacy and progression of cancer. Herein, we propose a novel biosensor ...based on specklegrams of tapered multimode fiber (MMF) and two-dimensional convolutional neural networks (2D-CNNs) for the detection of CEACAM5. The microfiber is modified with CEA antibodies to specifically recognize antigens. The biosensor utilizes the interference effect of tapered MMF to generate highly sensitive specklegrams in response to different CEACAM5 concentrations. A zero mean normalized cross-correlation (ZNCC) function is explored to calculate the image matching degree of the specklegrams. Profiting from the extremely high detection limit of the speckle sensor, variations in the specklegrams of antibody concentrations from 1 to 1000 ng/mL are measured in the experiment. The surface sensitivity of the biosensor is 0.0012 (ng/mL)
within a range of 1 to 50 ng/mL. Moreover, a 2D-CNN was introduced to solve the problem of nonlinear detection surface sensitivity variation in a large dynamic range, and in the search for image features to improve evaluation accuracy, achieving more accurate CEACAM5 monitoring, with a maximum detection error of 0.358%. The proposed fiber specklegram biosensing scheme is easy to implement and has great potential in analyzing the postoperative condition of patients.
Feature selection is a very important process in text classification. It can effectively eliminate redundant features and retain feature words with strong class distinguishing ability. In this paper, ...we propose a feature selection algorithm based on document frequency of segmented term frequency (STF-DF). In the algorithm, we also present two new concepts of "segmented term frequency" and "STF-DF. " Then, we compare STF-DF with six commonly used feature selection algorithms (document frequency, information gain, chi-square, CMFS, NDM, and t-test) on three popular datasets (20 Newsgroups, Classic3, and WebKB). Experimental results show that our proposed algorithm can improve the accuracy of text classification and make the classification more effective.
An optical fiber temperature sensor based on Mach–Zehnder interferometer and thermo-optic effect of the liquid crystal (LC) in fiber ring laser (FRL) system is proposed and experimentally ...demonstrated. The LC is infiltrated into the core of hollow core fiber, and the resonant wavelength is more sensitive to temperature variation due to the interaction between the incident light and the cavity infiltrating liquid crystal with high thermal light coefficient. Meanwhile, the FRL system was further used to make the sensor have good performance in the case of high signal-to-noise ratio (∼35 dB), narrow half-height width (FWHM = 0.15 nm), and high sensitivity in the temperature range from 20 °C to 50 °C, with the maximum sensitivity of 1.318 nm/°C. As far as we know, in the FRL system, the liquid crystal material has a better temperature sensing performance than the previous fiber. Nevertheless, the system has the advantages of good repeatability, low cost, simple production, small volume, high sensitivity. In marine microbial culture and detection, it is necessary to carry out high sensitivity measurement within a small temperature variation range. This reliable and excellent temperature performance has a potential application prospect.
Engineering unique electronic structure of catalyst to boost catalytic performance is of prime scientific and industrial importance. Herein, the identification of intrinsic electronic sensitivity for ...direct propene epoxidation was first achieved over highly stable Au/wormhole-like TS-1 catalyst. Results show that the electron transfer of Au species can be regulated by manipulating the dynamic evolutions and contents of Au valence states, thus resulting in different catalytic performance in 100 h time-on-stream. By DFT calculations, kinetic analysis and multi-characterizations, it is found that the Au0 species with higher electronic population can easily transfer more electrons to activate surface O2 compared with Au1+ and Au3+ species. Moreover, there is a positive correlation between Au0 content and activity. Based on this correlation, a facile strategy is further proposed to boost Au0 percentage, resulting in the reported highest PO formation rate without adding promoters. This work harbors tremendous guiding significance to the design of highly efficient Au/Ti-containing catalyst for propene epoxidation with H2 and O2.
The identification of intrinsic electronic sensitivity for propene epoxidation with H2 and O2 is achieved and the enhanced dynamic electron transfer of Au0 species by increasing the Au0 content boost the reaction performance of green propene epoxidation. Display omitted
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
A multisensor data fusion algorithm is proposed in this study for life detection in cluttered environments. The method consists of four steps: data acquisition, data preprocessing, data fusion, and ...result sort. First, four kinds of data (RGB image, RGB video, infrared image, and radar wave) are acquired from three different sensors (RGB camera, infrared camera, and life detection radar). Then, four specified algorithms are used on each data for data preprocessing. Third, an ordered weighted average (OWA)-based data fusion is used to fuse the four single results. The result is a sort of four possible results (Formula Omitted, Formula Omitted, Formula Omitted, and Formula Omitted). A series of cluttered environments are designed to verify the effectiveness of the proposed method. The results show that the data fusion method can effectively improve the success rate of life detection in cluttered environments. Specifically, the average accuracies of 97.8%, 96.7%, and 89.7% under different distances, light intensities, and shelter, respectively, are obtained.
Three-dimension hollow cubic carbon material is prepared from low-cost vacuum residuum, which demonstrates excellent activity and stability of two-electron oxygen reduction reaction. The formation ...mechanism of material has been systematically analyzed.
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Constructing efficient carbon material with enhanced mass transfer ability from vacuum residuum (VR) is of prime industrial and scientific significance. Herein, we demonstrated a one-pot synthesis of metal-free and highly symmetric hollow carbon cubes (HCCs) using cost-efficient vacuum residuum (VR) as a C/N/S source. By multi-techniques such as TEM, SEM, Raman, XPS, and XRD, it is found that the CTAB surfactant plays an important role in emulsifying and forming oil-in-water suspension particles. Subsequently, high aromatics contents in VR favor the formation of HCCs shell by graphitization on the surface of NaCl template. Notably, heavy metals (e.g., V, Ni) are not enriched in carbon skeleton due to the unique graphitization mechanism. This metal-free HCCs catalyst showed good catalytic stability and high selectivity towards direct and local electrochemical production of hydrogen peroxide (H2O2) through two-electron O2 reduction due to enhanced mass transfer ability. The results provide a novel avenue to synthesize metal-free cubic carbon material from low-cost and plentiful VR, which are essential to the design of more efficient catalysts for O2 reduction to H2O2.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Coronary artery disease (CAD) is a metabolically perturbed pathological condition. However, the knowledge of metabolic signatures on outcomes of CAD and their potential causal effects and impacts on ...left ventricular remodeling remains limited. We aim to assess the contribution of plasma metabolites to the risk of death and major adverse cardiovascular events (MACE) as well as left ventricular remodeling.
In a prospective study with 1606 Chinese patients with CAD, we have identified and validated several independent metabolic signatures through widely-targeted metabolomics. The predictive model respectively integrating four metabolic signatures (dulcitol, β-pseudouridine, 3,3',5-Triiodo-L-thyronine, and kynurenine) for death (AUC of 83.7% vs. 76.6%, positive IDI of 0.096) and metabolic signatures (kynurenine, lysoPC 20:2, 5-methyluridine, and L-tryptophan) for MACE (AUC of 67.4% vs. 59.8%, IDI of 0.068) yielded better predictive value than trimethylamine N-oxide plus clinical model, which were successfully applied to predict patients with high risks of death (P = 0.0014) and MACE (P = 0.0008) in the multicenter validation cohort. Mendelian randomisation analysis showed that 11 genetically inferred metabolic signatures were significantly associated with risks of death or MACE, such as 4-acetamidobutyric acid, phenylacetyl-L-glutamine, tryptophan metabolites (kynurenine, kynurenic acid), and modified nucleosides (β-pseudouridine, 2-(dimethylamino) guanosine). Mediation analyses show that the association of these metabolites with the outcomes could be partly explained by their roles in promoting left ventricular dysfunction.
This study provided new insights into the relationship between plasma metabolites and clinical outcomes and its intermediate pathological process left ventricular dysfunction in CAD. The predictive model integrating metabolites can help to improve the risk stratification for death and MACE in CAD. The metabolic signatures appear to increase death or MACE risks partly by promoting adverse left ventricular dysfunction, supporting potential therapeutic targets of CAD for further investigation.
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