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Temporal changes in electrical resistance of a nanopore sensor caused by translocating target analytes are recorded as a sequence of pulses on current traces. Prevalent algorithms for feature extraction in pulse-like signals lack objectivity because empirical amplitude thresholds are user-defined to single out the pulses from the noisy background. Here, we use deep learning for feature extraction based on a bi-path network (B-Net). After training, the B-Net acquires the prototypical pulses and the ability of both pulse recognition and feature extraction without a priori assigned parameters. The B-Net is evaluated on simulated data sets and further applied to experimental data of DNA and protein translocation. The B-Net results are characterized by small relative errors and stable trends. The B-Net is further shown capable of processing data with a signal-to-noise ratio equal to 1, an impossibility for threshold-based algorithms. The B-Net presents a generic architecture applicable to pulse-like signals beyond nanopore currents.

Drospirenone (DE) is a fourth-generation progesterone that has been widely used in oral contraceptives for women because of its safety and few side effects in terms of pharmacological activity. A new solvatomorph (crystal form C) of DE with dimethyl sulfoxide was identified and characterized for the first time through a thermogravimetry-mass spectrometry (TG-MS) coupling system. The thermodynamic property of the new solvatomorph of DE was different from those of most pharmaceutical solvatomorphs, and it was revealed via the skimmer-type interfaced TG-MS system and differential scanning calorimetry. This new solvatomorph and a polymorph of DE obtained without solvent (crystal form A) were well characterized by X-ray crystallography and vibrational spectroscopic analysis. Computational studies based on their single-crystal structures, such as Hirshfeld surface analyses, were used to determine the intermolecular interactions in the crystal network. The single-crystal structure of crystal form C of DE was determined and reported for the first time.

The application of certified reference materials (CRMs) to genetically modified organism (GMO) detection is essential for guaranteeing the accuracy, comparability, and traceability of quantitative results over time and among laboratories. Clean leaves from GM rice Kefeng 6 were used as raw materials to develop a batch of genomic DNA (gDNA) CRMs. The optimized KF6/PLD duplex digital PCR was used for collaborative characterization of Kefeng 6 gDNA CRMs by eight qualified laboratories; this batch of gDNA CRMs was certified for two property values, namely, copy number ratio and copy number concentration, which were 1.03 ± 0.04 and (1.60 ± 0.11) × 105 copies/μL, respectively. The gDNA CRMs displayed good between-vial homogeneity when the minimum sample intake of 2 μL was taken into account. Stability studies indicated that the gDNA CRMs should be transported below 25 °C, and cold chain transport was recommended. Shelf life was assessed to be at least 12 months, and when using gDNA CRMs, freeze–thaw should not exceed 10 cycles. Compared to the available gDNA CRMs in the market, this batch of gDNA CRMs has accurate property values with combined uncertainties, providing user-friendly calibrators for GM rice Kefeng 6 inspection and monitoring. The development and characterization of Kefeng 6 gDNA CRMs contribute to the establishment of a copy number-based reference system for GMO detection.

Ankylosing spondylitis (AS) is a chronic immune-mediated disease. Various immune cells play an essential role in the AS pathogenesis. However, the specific pathogenesis of AS has not been well understood. Proteomic profiles of peripheral blood mononuclear cells (PBMCs) were applied to reveal the specific pathogenesis of AS. Quantitative proteomic analyses were performed using liquid chromatography-tandem mass spectrometry (LC-MS/MS)-based methods to investigate the protein profiling of PBMCs from new-onset AS patients (n = 9) and healthy controls (n = 9). We identified 782 differentially expressed proteins (DEPs) and 527 differentially phosphorylated proteins (DPPs) between AS patients and healthy controls. The subcellular location of DEPs and DPPs showed that most of the DEPs were from the cytoplasm (n = 296, 38%), were extracellular (n = 141, 18%), and from the nucleus (n = 114, 15%); most of the DPPs were from the cytoplasm (n = 37, 34%), nucleus (n = 35, 32%), and plasma membrane (n = 10, 9%). We further identified 89 proteins with both expression and phosphorylation differences. The functional annotation of the 89 differentially expressed and phosphorylated proteins enriched in the antigen processing and presentation pathway. Four DEPs with six phosphorylated positions were found in the antigen processing and presentation pathway. The differentially expressed and phosphorylated proteins may be helpful to uncover the pathogenesis of AS. The six AS-specific proteins may serve as candidate markers for AS diagnosis and new treatment targets.

A series of NiMoP(x)-Al catalysts with different phosphorus contents were prepared by the incipient wetness co-impregnation method. The effects of phosphorus modification on the acidity, active phase nanostructure, and catalytic properties of the residue hydrodenitrogenation catalysts were investigated to find the role of phosphorus in the catalytic mechanism. The results of temperature-programmed desorption of NH3 and pyridine IR spectroscopy of the catalysts indicate that phosphorus modification can increase the total acid and Bronsted acid. Transmission electron microscopy analysis shows that phosphorus modification increases the stacking number N A, reduces the slab length L A of the active MoS2 phase, and increases the Mo dispersion f Mo, leading to the promotion of the sulfidation degree of the active Mo phase and thus increasing the denitrification rate. The catalyst with a 3.4 wt % P2O5 loading shows the highest Bronsted/Lewis acid ratio, the largest amount of three-layer active phases, the smallest L A, the highest f Mo, the optimal sulfurization degree, and the highest denitrification rate, 63.6%, indicating the correlation between the nanostructure of the active phase and its catalytic property because of the addition of phosphorus.

FactSage simulation, X-ray diffraction (XRD), and scanning electron microscopy (SEM) coupled to energy-dispersive spectroscopy (EDS) analyses were performed to explore the combined influence of SiO2 and O2 on the crystallization behavior of modified Ti-bearing blast furnace slag. The results of FactSage simulation showed that an increase in the added amount of SiO2 was beneficial to the conversion of Ti-bearing minerals into simple titanium oxides. An increase in oxidation time was conducive to the transformation of low-valent titanium oxides to tetravalent titanium oxide. Therefore, Ti components were precipitated only in the form of rutile under the optimal added amount of SiO2 (40 g) and the optimum oxidation time (126 s). The results of XRD and SEM analyses were well in agreement with the results of FactSage simulation. Moreover, the mechanism of formation of rutile and glassy phases was discussed.