A multiple x-ray-source array (MXA) system with a planar two-dimensional source distribution for digital breast tomosynthesis.

BACKGROUND: Digital breast tomosynthesis (DBT) has outpaced digital mammography in clinical adoption in the United States; however, substantial technological limitations remain to image quality in DBT, including undersampling from a one-dimensional (1D) scan geometry, x-ray source motion during acquisition, and patient motion artifacts from long exam times. PURPOSE: A thermionic cathode x-ray system employing two-dimensional (2D, planar) multiple x-ray-source arrays (MXA) is proposed to improve DBT image quality. METHODS: A 1D MXA, consisting of a linear array of thermionic cathodes was used to simulate a 2D MXA. The 1D MXA included 11 focal spots separated by a distance of Δ d ${{\Delta}}d$  = 23 mm. The 11 cathodes were paired with 11 molybdenum 50 mm diameter anode disks, mounted on a rotating shaft within a single vacuum enclosure. Image quality was investigated as a function of MXA configuration by integrating the 1D MXA with a 200 × 250 mm2 flat panel detector at a source-to-detector distance of 630 mm, resulting in a 20° tomographic arc. To simulate a 2D MXA, the detector (with phantom) was translated orthogonally to the linear array by a distance ( δ $\delta $ ) ranging from δ $\delta $  = 0 mm (conventional 1D) to δ $\delta $  = 57 mm. All sources operated at 30 kV with 80 mA and 4.5 mAs/pulse, yielding ∼100 mAs per DBT dataset. DBT reconstructions involved 22 projections and used filtered backprojection with a ramp and Hann apodization filter. Volumetric reconstructions for each source were weighted by sampling differences between sources, and averaged. Image quality was assessed in terms of contrast-to-noise ratio (CNR), background clutter noise and power spectrum, and slice sensitivity profile (SSP) using a set of physical phantoms, including: (i) contrast-detail signals coupled to spherical clutter (PMMA in air); (ii) an SSP phantom; (iii) a commercial "breast" phantom (CIRS BR3D, Sun Nuclear, Norfolk, VA); and (iv) bovine muscle. RESULTS: Background clutter noise amplitude reduced monotonically from the 1D MXA (σclutter = 5.9 A.U., δ $\delta $  = 0 mm) and 2D MXA arrays with increasing δ $\delta $ , with statistical significance between the 1D MXA and 2D MXA with δ $\delta $  = 57 mm (σclutter = 5.0 A.U., p < 0.001). The contrast-detail/clutter phantom demonstrated CNR from the 2D MXA (δ  = 57 mm) outperforming the 1D MXA in all combinations of contrast and detail. 2D power spectrum analysis of clutter demonstrated a pronounced Fourier domain null cone for the 1D MXA in the anterior field-of-view (away from the 1D MXA position), whereas the 2D MXA geometry (δ = 57 mm) did not exhibit the null cone. The SSP was 15%-50% narrower (FWHM) for the 2D versus the 1D geometry, across all reconstruction setups. CONCLUSIONS: The advantages of a 2D source geometry for DBT imaging were demonstrated quantitatively compared to a conventional 1D line of x-ray sources. The improvement in the 2D geometry was attributed both to improved Fourier domain sampling and reduced SSP. We conclude that 2D MXA sources have the potential to substantially improve DBT imaging in comparison to existing commercial DBT systems.

Anticipative Bayesian classification for data streams with verification latency.

Most of the existing adaptive classification algorithms in non-stationary data streams require recent labelled data for their updates. Such recent labels are often missing. For stream classification under verification latency only few approaches exist. Most of them assume clustered data or homogeneous drift in all features, which limits their applicability. We address this by proposing Anticipative Bayesian stream Classifier (ABClass), an approach that is capable of integrating and automatically selecting from different components. In its Bayesian classification framework, ABClass combines density estimation techniques, extended to extrapolate drift patterns over time, with unsupervised parameter tuning and unsupervised model selection. ABClass allows for multivariate density estimation and extrapolation techniques. In this work, we assume conditional independence between features given the class label for modelling feature-specific drift patterns. ABClass is generative and can also be used for explaining and visualising concept drift patterns. It is generic, making it easy to include further types of drift models, both for the class-conditional feature distribution and for the class prior distribution. The experimental evaluation on several real-world data streams shows its competitiveness compared to other state-of-the-art approaches. ABClass is in most cases ten- to hundred-times faster than its competitors, both for model fitting and for prediction.

Performance Analysis and Prediction of 5G Round-Trip Time Based on the VMD-LSTM Method.

With the increasing level of industrial informatization, massive industrial data require real-time and high-fidelity wireless transmission. Although some industrial wireless network protocols have been designed over the last few decades, most of them have limited coverage and narrow bandwidth. They cannot always ensure the certainty of information transmission, making it especially difficult to meet the requirements of low latency in industrial manufacturing fields. The 5G technology is characterized by a high transmission rate and low latency; therefore, it has good prospects in industrial applications. To apply 5G technology to factory environments with low latency requirements for data transmission, in this study, we analyze the statistical performance of the round-trip time (RTT) in a 5G-R15 communication system. The results indicate that the average value of 5G RTT is about 11 ms, which is less than the 25 ms of WIA-FA. We then consider 5G RTT data as a group of time series, utilizing the augmented Dickey-Fuller (ADF) test method to analyze the stability of the RTT data. We conclude that the RTT data are non-stationary. Therefore, firstly, the original 5G RTT series are subjected to first-order differencing to obtain differential sequences with stronger stationarity. Then, a time series analysis-based variational mode decomposition-long short-term memory (VMD-LSTM) method is proposed to separately predict each differential sequence. Finally, the predicted results are subjected to inverse difference to obtain the predicted value of 5G RTT, and a predictive error of 4.481% indicates that the method performs better than LSTM and other methods. The prediction results could be used to evaluate network performance based on business requirements, reduce the impact of instruction packet loss, and improve the robustness of control algorithms. The proposed early warning accuracy metrics for control issues can also be used to indicate when to retrain the model and to indicate the setting of the control cycle. The field of industrial control, especially in the manufacturing industry, which requires low latency, will benefit from this analysis. It should be noted that the above analysis and prediction methods are also applicable to the R16 and R17 versions.

Ribosome-inactivation by a class of widely distributed C-tail anchored membrane proteins.

Ribosome hibernation is a commonly used strategy that protects ribosomes under unfavorable conditions and regulates developmental processes. Multiple ribosome-hibernation factors have been identified in all domains of life, but due to their structural diversity and the lack of a common inactivation mechanism, it is currently unknown how many different hibernation factors exist. Here, we show that the YqjD/ElaB/YgaM paralogs, initially discovered as membrane-bound ribosome binding proteins in E. coli, constitute an abundant class of ribosome-hibernating proteins, which are conserved across all proteobacteria and some other bacterial phyla. Our data demonstrate that they inhibit in vitro protein synthesis by interacting with the 50S ribosomal subunit. In vivo cross-linking combined with mass spectrometry revealed their specific interactions with proteins surrounding the ribosomal tunnel exit and even their penetration into the ribosomal tunnel. Thus, YqjD/ElaB/YgaM inhibit translation by blocking the ribosomal tunnel and thus mimic the activity of antimicrobial peptides and macrolide antibiotics.

Angstrom-Level Tuning in Confined Space of Metal-Organic Framework for Ultra-High Resolution in Gas Chromatographic Separation.

Optimizing the balance between thermodynamic interaction and kinetic diffusion is pivotal to obtaining high-performance gas chromatographic stationary phases. Here, three aluminum-based metal-organic frameworks featuring fym topology were chosen to achieve such balance by refined controlling the thermodynamic interactions toward analytes at angstrom level in a confined space. The CAU-10-H with the middle-sized channels (5.4 Å) provided weak interactions with xylenes because of the benzene ring around the channel, leading to the fastest diffusion. While the MIL-160 provided stronger interactions toward the analytes due to the abundance of O-heterocyclic sites of 2,5-furandicarboxylic acid ligands, resulting in slightly higher diffusion barriers. Thereby, although MIL-160 had a larger channel (5.9 Å) than CAU-10-H, the xylenes still diffused more slowly in MIL-160 than in CAU-10-H. The CAU-10-NH2 with the channel of 4.7 Å provided overstrong thermodynamic interactions and significant stereospecific blockade to the analytes because of the NH2 sites in the confined channels. These factors collectively contributed to achieving the lowest diffusion kinetics. The confined interactions were also proved by molecular dynamics simulation. Furthermore, the application indicated that MIL-160 exhibited the highest separation ability as a GC stationary phase among all reported materials. This strategy offers an approach for developing high-performance MOF stationary phases.

Analysis of antibiotic response in Clinical Wound Pseudomonas aeruginosa isolates: Unveiling Proteome Dynamics of tobramycin tolerant phenotype.

Pseudomonas aeruginosa (P. aeruginosa) is an opportunistic human pathogen, causing serious chronic infections. P. aeruginosa can adapt efficiently to antibiotic stressors via different genotypic or phenotypic strategies such as resistance and tolerance. The adaptation regulatory system is not always very well understood. In this study, we use shotgun proteomics to investigate the system-level response to tobramycin in two clinical wound P. aeruginosa isolates and PAO1. We profiled each strain for its antibiotic drug-tolerant phenotype using supra-minimum inhibitory concentrations (supra-MIC) of tobramycin and applied proteomics to investigate the protein expression profiles. The MIC revealed that all isolates were susceptible to tobramycin but at supra-MIC concentrations at stationary growth, a degree of tolerance was observed for the isolates. We identified around 40 % of the total proteins encoded by the P. aeruginosa genome and highlighted shared and unique protein signatures for all isolates. Comparative proteome profiling in the absence of antibiotic treatment showed divergent fingerprints, despite similarities in the growth behavior of the isolates. In the presence of tobramycin, the isolates shared a common response in the downregulation of proteins involved in the two-component system, whereas stress response proteins were present at higher levels. Our findings provide insight into the use of proteomic tools to dissect the system-level response in clinical isolates in the absence and presence of antibiotic stress.

Bridged Ethylene Polyethylene Oxide Surfaces to Improve Packing Materials for Widepore Size Exclusion Chromatography.

Here, we describe the preparation of bridged ethylene polyethylene oxide (BE-PEO) surface-modified silica packing materials for size exclusion chromatography. BE-PEO surface-modified silica was hydrolyzed and subsequent 1H nuclear magnetic resonance analysis of hydrolysis products confirmed the successful formation of BE-PEO bonded surface. Silica particles exhibiting 3 µm diameters and 1000 Å nominal pore diameters were selected as a base material for this work out of the critical need to improve analytical capabilities for the testing of cell and gene therapy drug products. Accelerated high pH aging study revealed significant enhancement in column stability. Multi-angle light scattering noise measurements showed inordinately lower baseline noise. Moreover, we evaluated the chromatographic performance of BE-PEO silica-packed columns through separations of a protein test mixture, DNA ladder, monoclonal antibody-based therapeutics, and adeno-associated viruses. BE-PEO silica columns demonstrated high resolution, high recovery separations that were confirmed to be reproducible and capable of extended column lifetimes and exhibited low ionic and hydrophobic secondary interactions. In summary, BE-PEO silica particles have yielded a new level of performance, improved base stability, and inherently lower baseline noise. These novel widepore particles will facilitate more sensitive size-based detection and characterization of large biologics in the form of advanced gene therapy products.

Wide-pore fully porous mixed-mode octyl/pyridyl-bonded silica material with pH-dependent surface charge reversal for high-performance hydrophobic charge-induction chromatography of proteins.

In an attempt to overcome silanophilic interactions like observed on popular reversed-phase butyl­bonded silica stationary phases in protein HPLC, a mixed-mode stationary phase based on wide pore silica (3 µm, 300 Å) was prepared by co-immobilization of octyl and 2-pyridylethyl ligands. The surface modification was performed by a new approach using synthesized functional silatranes of the above ligands and prewetted silica. It allowed to generate a dense polymeric siloxane layer on the silica surface. Butyl-bonded silica and octyl/3-aminopropyl-bonded mixed-mode silica phases were prepared for comparison. The modified silicas were subsequently characterized by elemental analysis regarding ligand densities, by solid-state 29Si and 13C cross polarization/magic angle spinning nuclear magnetic resonance spectroscopy for confirming the surface-bonded structure, and by pH-dependent ζ-potential measurements via electrophoretic light scattering providing net surface charge information at distinct pH values. While the classical butyl­bonded stationary phase revealed negative ζ-potential over the entire pH range investigated (pH 3.5-9.5) due to residual silanols and the mixed-mode octyl/3-aminopropyl-bonded silica positive ζ-potential over the entire pH range, pH-dependent charge reversal was observed at approximately pH 5.5 for the octyl/pyridyl-bonded stationary phase. Then, a test set of proteins differing in hydrophobicities and isoelectric points was employed to evaluate the retention characteristics of all three synthesized stationary phases over the pH range of 3 to 7.5 by acetonitrile-gradient elution reversed-phase HPLC. Under acidic conditions (pH 3) the mixed-mode phases octyl/pyridyl-silica and octyl/aminopropyl-silica showed reduced retention and improved peak shapes due to repulsive interactions preventing silanophilic interactions, while protein separations by their hydrophobicities were achieved (repulsive charge-assisted protein RPLC). Finally, the prepared novel mixed-mode octyl/pyridyl-bonded stationary phase was evaluated in hydrophobic charge induction chromatography mode for protein separation of the same test set. Instead of an organic modifier gradient, elution was enforced by a pH gradient from almost neutral to acidic pH at constant organic modifier content of 10 %. This chromatographic mode showed orthogonal retention characteristics and reversed elution order compared to above organic gradient RP-HPLC. In addition, significantly less organic solvent was used under these conditions, classifying it as a green protein LC technology.

Adaptive nonlinear filtering algorithms for removal of non-stationary noise in electronystagmographic signals.

Non-stationary physiological noise poses significant difficulties due to its time-varying and previously unknown characteristics. When processing electronystagmographic signals, linear filtering can distort diagnostically significant rapid changes caused by saccadic eye movements. In such cases, nonlinear filters based on robust estimators are more appropriate, whereas linear filtering effectively reduces white noise in parts of a signal with linear behaviour. Therefore, an adaptive signal processing approach that varies in nonlinearity from highly nonlinear robust estimation to linear averaging and combines their benefits appears promising. We have proposed a low-complexity adaptive method for switching filter sets and relevant filter parameter settings based on the estimated noise level and local signal behaviour. This method does not require time for filter parameter modification and does not need prior information on the signal model and noise variance. Based on this method, we have designed adaptive nonlinear filtering algorithms to exploit the advantages of both the nonlinear robust and linear averaging estimators. We have evaluated the filtering quality statistically using the minimum mean square error criteria and the maximum signal-to-noise ratio for a model signal with different levels of additive Gaussian noise. The proposed real-time adaptive filtering algorithms demonstrate a significant efficiency improvement compared to the commonly used filters. The proposed adaptive myriad algorithm achieves the highest efficiency by adjusting a sample myriad linearity parameter depending on the local estimate of a signal scale and changing the sliding window length and the coefficient affecting the linearity parameter.

Zirconium(IV) coordination-mediated rapid and versatile post-modification of polydopamine coating as stationary phase for open-tubular capillary electrochromatography.

In recent years, mussel-inspired polydopamine (PDA)-based materials have attracted significant attention in the field of open-tubular capillary electrochromatography (OT-CEC) owing to their diverse and appealing properties. However, previously established functionalized PDA coating-based CEC stationary phases predominantly relied on the latent reactivity of PDA with amine/thiol-containing molecules, limiting the types of applicable modifiers and requiring time-consuming reaction processes. Herein, we presented a versatile and efficient method for the facile and rapid fabrication of diverse functionalized PDA coatings as OT-CEC stationary phases through a Zr(IV) coordination-mediated post-modification strategy. Different kinds of modifiers, including octadecylamine (ODA), lauric acid (LA), and perfluorooctanoic acid (PFOA), were rapidly and robustly grafted onto the PDA coating, verified through multiple characterization techniques. The influences of preparation parameters on the grafting efficiency of the functionalized PDA coating were systematically investigated. Utilizing the Zr(IV)-mediated ODA-, LA- and PFOA-functionalized PDA-based OT-CEC columns, we achieved high-efficiency baseline separation of a series of neutral analytes with excellent repeatability, good stability, and long lifetime. Given the strong universality of the Zr(IV) coordination-mediated post-modification approach, our study provides an effective pathway for advancing the development of a wider range of functional PDA-based chromatographic stationary phases.

Stereoisomeric separation and chiral recognition mechanism study of star cyclodextrin polymer as the chiral stationary phase.

BACKGROUND: As the derivatives of cyclodextrin (CD), cyclodextrin polymers (CDPs) effectively increase the concentration of CD units and construct supramolecular structures with unique stereoselectivity by the structure design. CDPs have shown significant potential in chiral separation, however, the process of stereoselective interactions on chiral stationary phases (CSPs) and the specific contribution of intermolecular forces are still a challenge issue. A comprehensive understanding of the chiral recognition mechanism of CDPs will help to optimize chiral separation conditions and design new CSPs. RESULTS: The star CDP with a supermolecular structure was synthesized by grafting ß-CD onto the external 6-position hydroxyl groups using ß-CD as the parent nucleus. The enhanced host-guest recognition ability of CD supramolecular polymer structure provided better inclusion interaction and increased chiral recognition of the isomers. The Star-CD CSP with star CDP as a chiral ligand performed satisfactory stereoisomer separation ability with the separation factor (α) up to 2.0 for various quinoline alkaloid isomers and 1.89 for catechins. To elucidate its chiral separation mechanism, molecular docking was used to construct the three-dimensional visual models of the binding sites and the contribution of non-covalent interactions between Star-CD CSP and quinoline alkaloid isomers. In addition, the formation sites of non-covalent interactions on the CD monomers of the polymer side chains were confirmed from the actual geometric structure by analyzing the NMR chemical shift changes before and after the formation of complexes between Star-CD polymers and isomers. Combined with the mutual evidence of molecular simulation and chiral NMR, the specific recognition mechanism of selector-selectand complexes was comprehensively expounded. SIGNIFICANCE: The multi-mode CSP based on cyclodextrin supramolecular structure provides new ideas for the stereoisomeric separation of complex chiral components with multiple chiral centers in natural products. Not limited to the macroscopic performance of the chromatographic separation, molecular docking explored the theoretical model of chiral recognition from the molecular level. The chiral NMR analysis confirmed the credibility of the model from the geometry structure, and then the recognition mechanism of multi-mode CSP was fully elaborated combining the above three aspects.

A Polymer-Based Polar Stationary Phase Grafted With Modified Lysine for Hydrophilic Interaction Chromatography.

The high hydrophobicity and chemical inertness of poly(styrene-divinylbenzene) (PS-DVB) microspheres make their surface hydrophilic modification difficult. Here we describe a facile way to convert PS-DVB microspheres to hydrophilic, then can be used as polar stationary phase for hydrophilic interaction chromatography. This approach utilizes the grafting of an acrylamide-terminated lysine zwitterionic monomer onto PS-DVB microspheres via free radical polymerization. The obtained stationary phase shows good hydrophilicity and a typical retention mechanism of hydrophilic interaction chromatography toward several model polar analytes. It also exhibits obvious zwitterionic properties and is capable of separating cationic and anionic analytes simultaneously. The column shows negligible bleeding level, much superior to silica-based ones.

Preparation of Chiral Stationary Phase Based on 1,1'-bi-2-Naphthol for Chiral Enantiomer Separation.

Two enantiomeric novel chiral stationary phases (CSPs) R-3-Amide-BINOL CSP (CSP-1) and S-3-Amide-BINOL CSP (CSP-2) were prepared using (R/S)-1,1'-bi-2-naphthol (BINOL) derivatives as chiral selectors. The structure of CSPs was characterized by nuclear magnetic resonance, scanning electron microscope and elemental analysis. Four chiral solutes were selected under normal phase HPLC conditions to evaluate the chiral separation ability of the two novel CSPs. The effects of mobile phase and acidic additives on enantiomeric separation were investigated. The combination of molecular docking simulation and experimental data has elucidated the crucial role of hydrogen bonds and π-π interactions formed between the analyte and CSP in chiral recognition, and different configurations of CSP can cause enantiomeric elution sequence reversal, indicating that the configuration of chiral selectors in CSP has a significant impact on chiral recognition ability.

Analysis of a stochastic SEI u I r R epidemic model incorporating the Ornstein-Uhlenbeck process.

This article aims to analyze a stochastic epidemic model S E I u I r R (Susceptible-exposed-undetected infected-detected infected (reported -recovered) assuming that the transmission rate at which people undetected become detected is perturbed by the Ornstein-Uhlenbeck process. Our first objective is to prove that the stochastic model has a unique positive global solution by constructing a nonnegative Lyapunov function. Afterward, we provide a sufficient criterion to prove the existence of an ergodic stationary distribution of the mode by constructing a suitable series of Lyapunov functions. Subsequently, we establish sufficient conditions for the extinction of the disease. Finally, a series of numerical simulations are carried out to illustrate the theoretical results.

Monomer-mediated growth of ß-cyclodextrin-based microporous organic network as stationary phase for capillary electrochromatography.

CD-MONs (ß-cyclodextrin-based microporous organic networks), derived from ß-cyclodextrin, possess notable hydrophobic characteristics, a considerable specific surface area, and remarkable stability, rendering them highly advantageous in separation science. This research aimed to investigate the utility of CD-MONs in chromatography separation. Through a monomer-mediated technique, we fabricated an innovative CD-MON modified capillary column for application in open-tubular capillary electrochromatography (OT-CEC). The CD-MON-based stationary phase on the capillary's inner surface was analyzed using Fourier transform infrared (FT-IR) spectroscopy and scanning electron microscopy (SEM). We assessed the performance of the CD-MON modified capillary column for separation purposes. The microstructure and pronounced hydrophobicity of CD-MON contributed to enhanced selectivity and resolution in separating diverse hydrophobic analytes, such as alkylbenzenes, halogenated benzenes, parabens, and polycyclic aromatic hydrocarbons (PAHs). The maximum column efficiency achieved was 1.5 × 105 N/m. Additionally, the CD-MON modified capillary column demonstrated notably high column capacity, with a methylbenzene mass loading capacity of up to 197.9 pmol, surpassing that of previously reported porous-material-based capillaries. Furthermore, this self-constructed column was effectively utilized for PAHs determination in actual environmental water samples, exhibiting spiked recoveries ranging from 93.2 to 107.9% in lake water samples. These findings underscore the potential of CD-MON as an effective stationary phase in separation science.

Randomized crossover trial of a demand oxygen delivery system in nocturnal hypoxemia.

The newly developed portable oxygen concentrator with an auto-demand oxygen delivery system (auto-DODS) automatically switches between 3 sensitivities according to the negative pressure gradient of inhalation and supplies oxygen only during inhalation. The aim of this study was to verify the effectiveness and safety of auto-demand devices compared with a continuous flow oxygen concentrator, during sleep, in a randomized crossover noninferiority trial. We alternatively used an auto-DODS or a continuous-flow oxygen concentrator, all night on separate days for HOT (Home Oxygen Therapy) patients with nocturnal hypoxemic symptoms. The primary endpoints were the mean value of oxygen saturation (SpO2) over the total sleep time. The secondary endpoints included the efficacy endpoints and the safety endpoints. Regarding the primary endpoint, the difference in SpO2 between the auto-DODS and continuous flow was 0.835%. Since the upper limit of this difference did not exceed 2.8, which was set as the noninferiority margin, it was shown that the auto-DODS did not reduce SpO2 by at least 2.8% on average compared to continuous flow. No equipment failure or exacerbation of disease was observed, confirming the safety of the auto-DODS during the night.

Hydrogen-bonded organic frameworks as stationary phase for open-tubular capillary electrochromatography.

BACKGROUND: Capillary electrochromatography (CEC) stationary phases have always been the focus of attention. The selection of excellent stationary phases are the key to realize separate of different compounds. Hydrogen-bonded organic frameworks (HOFs) are porous materials connected by hydrogen bonds between molecules, which have the advantages of renewable, high specific surface area and mild synthesis conditions. At present, HOFs are used in gas adsorption and storage, catalysis and drug delivery. Because of its unique advantages, HOFs have a bright future as CEC stationary phases. RESULTS: Using melamine (MA) and 1,3,6,8-tetra (4-carboxylphenyl)pyrene (H4TBAPy) as reaction monomers, a HOFs named MA/PFC-1 was synthesized by solvent evaporation at room temperature. The inner wall of the capillary column was coated with MA/PFC-1 by chemical bonding. Sulfonamides were used as the target analytes. The effects of pH, phosphate buffer solution concentration, organic additive content and applied voltage on sulfonamides separation were investigated. The MA/PFC-1-coated capillary column had good resolution (>1.5) and reproducibility. The intra-day, inter-day, column-to-column, and inter-batch precision of the retention times were 0.03%-0.09%, 0.04%-0.09%, 0.03%-0.14% and 0.06%-0.09%, respectively. The intra-day, inter-day, column-to-column, and inter-batch precision of the peak areas were 0.11%-0.25%, 0.13%-0.20%, 0.12%-0.15% and 0.08%-0.15%, respectively. The MA/PFC-1-coated capillary column was run 150 consecutive times, and the results showed no noticeable change, which proved that this method had good stability. SIGNIFICANCE: This work applied HOFs to CEC. The results show the that MA/PFC-1-coated capillary column has good separation performance. The MA/PFC-1-coated capillary column has been successfully applied to the determination of sulfamethoxazole in tablets, which has practical application value. To open up the application of HOFs in CEC and provide a new idea for developing new CEC stationary phases.

Low swelling and high mechanical strength organosilane hybrid polydivinylbenzene microspheres for hydrophilic interaction chromatography applications.

In this work, monodisperse organosilane hybrid polymer microspheres with a particle size of about 5 µm were synthesized using seed swelling polymerization. The organosilicon reagent methacryloxypropyltrimethoxysilane was introduced into the polymer framework as a copolymerization monomer, and the crosslinking degree of the microspheres was improved by the hydrolysis-condensation reaction of siloxanes. The synthesized hybrid microspheres have good mechanical strength as well as low swelling, with swelling propensity values of 0.167 and 0.348 in methanol and acetonitrile, respectively. Hybrid microspheres modified with cysteine have a hydrophilic interaction chromatography/reversed-phase liquid chromatography mixed-mode retention mechanism. Compared to the commercial cysteine-modified silica column, the synthesized stationary phase has higher separation selectivity for partially acidic or basic samples and better basic resistance for use under high pH mobile phase conditions (at least 10).

Methods and Software Tools for Reliable Operation of Flying LiFi Networks in Destruction Conditions.

The analysis of utilising unmanned aerial vehicles (UAVs) to form flying networks in obstacle conditions and various algorithms for obstacle avoidance is conducted. A planning scheme for deploying a flying LiFi network based on UAVs in a production facility with obstacles is developed and described. Such networks are necessary to ensure reliable data transmission from sensors or other sources of information located in dangerous or hard-to-reach places to the crisis centre. Based on the planning scheme, the following stages are described: (1) laying the LiFi signal propagation route in conditions of interference, (2) placement of the UAV at the specified points of the laid route for the deployment of the LiFi network, and (3) ensuring the reliability of the deployed LiFi network. Strategies for deploying UAVs from a stationary depot to form a flying LiFi network in a room with obstacles are considered, namely the strategy of the first point for the route, the strategy of radial movement, and the strategy of the middle point for the route. Methods for ensuring the uninterrupted functioning of the flying LiFi network with the required level of reliability within a given time are developed and discussed. To implement the planning stages for deploying the UAV flying LiFi network in a production facility with obstacles, the "Simulation Way" and "Reliability Level" software tools are developed and described. Examples of utilising the proposed software tools are given.

Simplified Synthesis of Poly(ethyleneimine)-Modified Silica Particles and Their Application in Oligosaccharide Isolation Methods.

There are great challenges in the field of natural product isolation and purification and in the pharmacological study of oligosaccharide monomers. And these isolation and purification processes are still universal problems in the study of natural products (NPs), traditional Chinese medicine (TCM), omics, etc. The same polymer-modified materials designed for the special separation of oligosaccharides, named Sil-epoxy-PEI and Sil-chloropropyl-PEI, were synthesized via two different methods and characterized by scanning electron microscopy combined with energy spectrum analysis, Fourier transform infrared spectroscopy, thermogravimetric analysis, zeta potential as well as surface area analysis, etc. Several nucleotide/nucleoside molecules with different polarities and selectivities were successfully isolated in our laboratory using stainless-steel columns filled with the synthesized material. In addition, the separation of saccharide probes and oligosaccharides mixtures in water extracts of Morinda officinalis were compared in HILIC mode. The results showed that the resolution of separations for the representative analytes of the Sil-epoxy-PEI column was higher than for the Sil-chloropropyl-PEI column, and the developed stationary phase exhibited improved performance compared to hydrothermal carbon, amide columns and other HILIC materials previously reported.