As a critical component in the smart grid, the Distribution Terminal Unit (DTU) dynamically adjusts the running status of the entire smart grid based on the collected electrical parameters to ensure ...the safe and stable operation of the smart grid. However, as a real-time embedded device, DTU has not only resource constraints but also specific requirements on real-time performance, thus, the traditional anomaly detection method cannot be deployed. To detect the tamper of the program running on DTU, we proposed a power-based non-intrusive condition monitoring method that collects and analyzes the power consumption of DTU using power sensors and machine learning (ML) techniques, the feasibility of this approach is that the power consumption is closely related to the executing code in CPUs, that is when the execution code is tampered with, the power consumption changes accordingly. To validate this idea, we set up a testbed based on DTU and simulated four types of imperceptible attacks that change the code running in ARM and DSP processors, respectively. We generate representative features and select lightweight ML algorithms to detect these attacks. We finally implemented the detection system on the windows and ubuntu platform and validated its effectiveness. The results show that the detection accuracy is up to 99.98% in a non-intrusive and lightweight way.
Thousands of Coronavirus Disease 2019 (COVID-19) patients have been discharged from hospitals Persistent follow-up studies are required to evaluate the prevalence of post-COVID-19 fibrosis.
This ...study involves 462 laboratory-confirmed patients with COVID-19 who were admitted to Shenzhen Third People's Hospital from January 11, 2020 to April 26, 2020. A total of 457 patients underwent thin-section chest CT scans during the hospitalization or after discharge to identify the pulmonary lesion. A total of 287 patients were followed up from 90 to 150 days after the onset of the disease, and lung function tests were conducted about three months after the onset. The risk factors affecting the persistence of pulmonary fibrosis were identified through regression analysis and the prediction model of the persistence of pulmonary fibrosis was established.
Parenchymal bands, irregular interfaces, reticulation and traction bronchiectasis were the most common CT features in all COVID-19 patients. During the 0-30, 31-60, 61-90, 91-120 and > 120 days after onset, 86.87%, 74.40%, 79.56%, 68.12% and 62.03% patients developed with pulmonary fibrosis and 4.53%, 19.61%, 18.02%, 38.30% and 48.98% patients reversed pulmonary fibrosis, respectively. It was observed that Age, BMI, Fever, and Highest PCT were predictive factors for sustaining fibrosis even after 90 days from onset. A predictive model of the persistence with pulmonary fibrosis was developed based-on the Logistic Regression method with an accuracy, PPV, NPV, Sensitivity and Specificity of the model of 76%, 71%, 79%, 67%, and 82%, respectively. More than half of the COVID-19 patients revealed abnormal conditions in lung function after 90 days from onset, and the ratio of abnormal lung function did not differ on a statistically significant level between the fibrotic and non-fibrotic groups.
Persistent pulmonary fibrosis was more likely to develop in patients with older age, higher BMI, severe/critical condition, fever, a longer viral clearance time, pre-existing disease and delayed hospitalization. Fibrosis developed in COVID-19 patients could be reversed in about a third of the patients after 120 days from onset. The pulmonary function of less than half of COVID-19 patients could turn to normal condition after three months from onset. An effective prediction model with an average area under the curve (AUC) of 0.84 was established to predict the persistence of pulmonary fibrosis in COVID-19 patients for early diagnosis.
In this study, a new rapid cleanup method was developed for the analysis of 111 pesticide multi-residues in lettuce and Chinese chives by GC-MS/MS and LC-MS/MS. QuEChERS (quick, easy, cheap, ...effective, rugged and safe)-based sample extraction was used to obtain the extracts, and the cleanup procedure was carried out using a Sin-QuEChERS nano cartridge. Comparison of the cleanup effects, limits of quantification and limits of detection, recoveries, precision and matrix effects (MEs) between the Sin-QuEChERS nano method and the classical dispersive solid phase extraction (d-SPE) method were performed. When spiked at 10 and 100 μg/kg, the number of pesticides with recoveries between 90% to 110% and relative standard deviations < 15% were greater when using the Sin-QuEChERS nano method. The MEs of Sin-QuEChERS nano and d-SPE methods ranged between 0.72 to 3.41 and 0.63 to 3.56, respectively. The results verified that the Sin-QuEChERS nano method was significantly more effective at removing pigments and more convenient than the d-SPE method. The developed method with the Sin-QuEChERS nano cleanup procedure was applied successfully to determine pesticide residues in market samples.
•Polysaccharide contents of shiitake mushrooms decreased in all the MAPs.•All the active MAPs increased total phenolic content and free amino acid levels.•Low oxygen packaging induced an anaerobic ...atmosphere and damage to tissue membranes.•High oxygen and medium oxygen packaging better maintained nutritional compound levels.
The effect of active modified atmosphere packaging with different initial gas compositions on fresh shiitake mushrooms was investigated. Shiitake mushrooms were packaged under each of the following conditions: (1) high oxygen packaging (HOP), 100% oxygen initially; (2) medium oxygen packaging (MOP), 50% O2 and balanced with N2 initially; (3) low oxygen packaging (LOP), 3% O2/5% CO2, balanced with N2 initially. Passive modified atmosphere packaging with air inside initially (AIR) was used as the control treatment. All the packaged samples were stored at 10°C with 90% RH for 7 days. During storage, gas compositions, electrolyte leakage, crude water-soluble polysaccharides, total phenolic content and free amino acid content were determined. The results showed that ethanol release was high in LOP and AIR but retarded in MOP and HOP. No packaging could prevent the decrease in polysaccharide content decreasing. Both the active and passive modified atmosphere packaging maintained the color and integrity of the mushrooms. The active modified atmosphere packaging had a significant effect on the increase of total phenolic content and total amount of free amino acids. LOP had a harmful impact on mushrooms with high levels of electrolyte leakage. In conclusion, HOP and MOP had a better effect on maintaining the nutritional compounds of shiitake mushrooms.
Peptides present an alternative modality to immunoglobulin domains or small molecules for developing therapeutics to either agonize or antagonize cellular pathways associated with diseases. However, ...peptides often suffer from poor chemical and physical stability, limiting their therapeutic potential. Disulfide-constrained peptides (DCP) are naturally occurring and possess numerous desirable properties, such as high stability, that qualify them as drug-like scaffolds for peptide therapeutics. DCPs contain loop regions protruding from the core of the molecule that are amenable to peptide engineering via direct evolution by use of phage display technology. In this study, we have established a robust platform for the discovery of peptide therapeutics using various DCPs as scaffolds. We created diverse libraries comprising seven different DCP scaffolds, resulting in an overall diversity of 2 x 1011. The effectiveness of this platform for functional hit discovery has been extensively evaluated, demonstrating a hit rate comparable to that of synthetic antibody libraries. By utilizing chemically synthesized and in vitro folded peptides derived from selections of phage displayed DCP libraries, we have successfully generated functional inhibitors targeting the HtrA1 protease. Through affinity maturation strategies, we have transformed initially weak binders against Notch2 with micromolar Kd values to high-affinity ligands in the nanomolar range. This process highlights a viable hit-to-lead progression. Overall, our platform holds significant potential to greatly enhance the discovery of peptide therapeutics.
The meridional propagation of Rossby waves links different latitudes. Traditional wave propagation theory is mostly discussed in the non-divergent atmosphere. This work emphasizes the influence of ...the divergent effect on wave propagation by analyzing wave solutions to the linearized shallow-water quasi-geostrophic potential vorticity equation on the zonal mean flow. Changes in the basic-state quantities and wave solutions generated from consideration of the divergent effect are highlighted. Compared with the non-divergent situation, more waves are allowed to exist and propagate to much higher latitudes in the divergent case. The turning latitudes are generally moved northward when the divergent effect is included. This main conclusion is robust in the idealized super-rotational flow and 300 hPa climatological flows in winter and summer. The divergent effect also tends to slow the speed of wave propagation and favor waves reaching remoter longitudes. These finding implicates Rossby wave propagation with divergent effect may contribute more to the long-distance teleconnection than that in non-divergent case.
Sweet tea, which functions as tea, sugar and medicine, was listed as a new food resource in 2017. Flavonoids are the main medicinal components in sweet tea and have significant pharmacological ...activities. Therefore, the quality of sweet tea is related to the content of flavonoids. Flavonoid content in plants is normally determined by time-consuming and expensive chemical analyses. The aim of this study was to develop a methodology to measure three constituents of flavonoids, namely, total flavonoids, phloridin and trilobatin, in sweet tea leaves using near-infrared spectroscopy (NIR).
In this study, we demonstrated that the combination of principal component analysis (PCA) and NIR spectroscopy can distinguish sweet tea from different locations. In addition, different spectral preprocessing methods are used to establish partial least squares (PLS) models between spectral information and the content of the three constituents. The best total flavonoid prediction model was obtained with NIR spectra preprocessed with Savitzky-Golay combined with second derivatives (SG + D2) (R
= 0.893, and RMSEP = 0.131). For trilobatin, the model with the best performance was developed with raw NIR spectra (R
= 0.902, and RMSEP = 2.993), and for phloridin, the best model was obtained with NIR spectra preprocessed with standard normal variate (SNV) (R
= 0.818, and RMSEP = 1.085). The coefficients of determination for all calibration sets, validation sets and prediction sets of the best PLS models were higher than 0.967, 0.858 and 0.818, respectively.
The conclusion indicated that NIR spectroscopy has the ability to determine the flavonoid content of sweet tea quickly and conveniently.
Lipid droplets (LDs) targeting probes are important for investigating the biological functions of LDs. The interplay between LDs and some other organelles can help to further understand the ...biological functions of these organelles. However, it is still a challenge to design functional probes that can specifically target LDs and are responsive to some other organelles. Herein, a multifunctional aggregation-induced emission luminogen (AIEgen), namely the TPA-CN, was prepared by the simple aldimine condensation reaction for lipid droplet-specific imaging and tracing. TPA-CN can be sensitively responsive to the acid environment of lysosomes due to the pH-response detachable connector in TPA-CN. With the assistance of this characteristic, it can be concluded from the fluorescence imaging and co-localization analysis results that the internalization of TPA-CN and the targeting of LDs does not involve the lysosome and the lysosomal escape process. At last, the TPA-CN was successfully used for the high-sensitivity imaging of dynamic information of LDs.
Tropical Indo-western Pacific convection anomalies influence atmospheric circulation, impacting climate far beyond the tropics. Here we present observational and modelling evidence for an ...interhemispheric effect of the boreal summer (June–August) Indo-Pacific convection oscillation (IPCO), which is characterized by a zonal seesaw pattern between the north Indian Ocean (NIO) and the western North Pacific (WNP). It is found that the IPCO is significantly correlated with simultaneous rainfall over many parts of the Southern Hemisphere (SH), including western Australia and western Brazil. These interhemispheric connections in rainfall remain significant when then El Niño–Southern Oscillation, the Indian Ocean Dipole, and the SH Annular Mode related signals are excluded simultaneously, which may help to improve the SH seasonal predictions. The physical mechanism that underlies this interhemispheric connection is investigated using observations, Rossby wave diagnostics and a series of atmospheric model experiments. Results suggest that convective heating anomalies associated with the IPCO excite two distinct southward-propagating equivalent barotropic wave trains that propagate into the extratropics in the SH: the South Africa–mid-latitudes wave train excited by the heat sink over the NIO, and the Maritime Continent–subtropical Australia wave train excited by the heat source over the WNP. We further demonstrate that upper tropospheric northerlies over tropical Africa and the Indian Ocean are responsible for the southward propagation of stationary Rossby waves across the easterlies. These equivalent barotropic waves then modulate the moisture transport, baroclinicity, and mid-latitude storminess, and thus affect rainfall anomalies in the SH. The new wave train patterns provide novel insight into the teleconnection pathways of convective heating over the tropical Indian Ocean and western Pacific.
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