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Background: Acute pancreatitis (AP) is a clinically common acute abdominal disease, whose pathogenesis remains unclear. The severe patients usually have multiple complications and lack specific drugs, leading to a high mortality and poor outcome. Acinar cells are recognized as the initial site of AP. However, there are no precise single-cell transcriptomic profiles to decipher the landscape of acinar cells during AP, which are the missing pieces of jigsaw we aimed to complete in this study. Methods: A single-cell sequencing dataset was used to identify the cell types in pancreas of AP mice and to depict the transcriptomic maps in acinar cells. The pathways' activities were evaluated by gene sets enrichment analysis (GSEA) and single-cell gene sets variation analysis (GSVA). Pseudotime analysis was performed to describe the development trajectories of acinar cells. We also constructed the protein–protein interaction (PPI) network and identified the hub genes. Another independent single-cell sequencing dataset of pancreas samples from AP mice and a bulk RNA sequencing dataset of peripheral blood samples from AP patients were also analyzed. Results: In this study, we identified genetic markers of each cell type in the pancreas of AP mice based on single-cell sequencing datasets and analyzed the transcription changes in acinar cells. We found that acinar cells featured acinar-ductal metaplasia (ADM), as well as increased endocytosis and vesicle transport activity during AP. Notably, the endoplasmic reticulum stress (ERS) and ER-associated degradation (ERAD) pathways activated by accumulation of unfolded/misfolded proteins in acinar cells could be pivotal for the development of AP. Conclusion: We deciphered the distinct roadmap of acinar cells in the early stage of AP at single-cell level. ERS and ERAD pathways are crucially important for acinar homeostasis and the pathogenesis of AP. [ABSTRACT FROM AUTHOR]

The Boussinesq equations with partial or fractional dissipation not only naturally generalize the classical Boussinesq equations but also are physically relevant and mathematically important. Unfortunately, it is not often well‐understood for many ranges of fractional powers. This paper focuses on a system of the 3D Boussinesq equations with fractional horizontal (−Δh)αu$$ {\left(-{\Delta}_h\right)}^{\alpha }u $$ and (−Δh)βθ$$ {\left(-{\Delta}_h\right)}^{\beta}\theta $$ dissipation and proves that if the initial data (u0,θ0$$ {u}_0,{\theta}_0 $$) in the Sobolev space H3(ℝ3)$$ {H}^3\left({\mathrm{\mathbb{R}}}^3\right) $$ are close enough to the hydrostatic balance state, respectively, the equations with α,β∈12,1$$ \alpha, \beta \in \left(\frac{1}{2},1\right] $$ then always lead to a steady solution. [ABSTRACT FROM AUTHOR]

An open tubular capillary electrochromatography column covalently bonded with polystyrene sulfonate was prepared via in situ polymerization using functionalized Azo‐initiator 4,4′‐Azobis(4‐cyanopentanoyl chloride). Scanning electron, fluorescence, and atomic force microscopy techniques showed the formation of a relatively rough layer of polymer. In addition, –CN and C = O stretching vibrations from infrared spectroscopy proved the successful immobilization of the azo‐initiator through covalent bonding and X‐ray photoelectron spectroscopy confirmed the elemental composition of the formed polymer layer. The prepared column was found to be appropriate for small and medium‐sized molecules separation. Compared to bare fused silica capillary column higher selectivity and resolution were obtained for the separation of alkaloids, sulfonamides, and peptides as a result of the electrostatic and pi‐pi stacking interactions between the small organic molecules and the coated column without compromising the electroosmotic flow mobility. Separation efficiency was also increased compared to the bare capillary for the separation of alkaloids (about 1.5 times). Moreover, intraday, inter‐day, intra‐batch, and inter‐batch relative standard deviation values of retention time and peak area of peptides were within 2% and 10%, respectively, indicating good repeatability of the column preparation procedure. The developed method for the covalent bonding of polymers through a functionalized azo‐initiator could represent a promising stable method for the preparation of an open tubular column. [ABSTRACT FROM AUTHOR]

The important metabolic characteristics of cancer cells include increased fat production and changes in amino acid metabolism. Based on the category of tumor, tumor cells are capable of synthesizing as much as 95% of saturated and monounsaturated fatty acids through de novo synthesis, even in the presence of sufficient dietary lipid intake. This fat transformation starts early when cell cancerization and further spread along with the tumor cells grow more malignant. In addition, local catabolism of tryptophan, a common feature, can weaken anti-tumor immunity in primary tumor lesions and TDLN. Arginine catabolism is likewise related with the inhibition of anti-tumor immunity. Due to the crucial role of amino acids in tumor growth, increasing tryptophan along with arginine catabolism will promote tumor growth. However, immune cells also require amino acids to expand and distinguish into effector cells that can kill tumor cells. Therefore, it is necessary to have a deeper understanding of the metabolism of amino acids and fatty acids within cells. In this study, we established a method for the simultaneous analysis of 64 metabolites consisting of fatty acids and amino acids, covering biosynthesis of unsaturated fatty acids, aminoacyl-tRNA biosynthesis, and fatty acid biosynthesis using the Agilent GC-MS system. We selected linoleic acid, linolenic acid, sodium acetate, and sodium butyrate to treat H460 cells to validate the current method. The differential metabolites observed in the four fatty acid groups in comparison with the control group indicate the metabolic effects of various fatty acids on H460 cells. These differential metabolites could potentially become biomarkers for the early diagnosis of lung cancer. [ABSTRACT FROM AUTHOR]

Perfluorooctanoic acid (PFOA) is a novel type of persistent synthetic organic pollutant, and its exposure on pregnant women can cause some adverse effects, such as pregnancy-induced hypertension, gestational diabetes mellitus, and preeclampsia. Therefore, understanding the metabolic changes caused by PFOA exposure is of great significance to protect pregnant women from its adverse effects. In this study, the metabolomes from the urine samples of pregnant women exposure to PFOA at different degrees were analyzed by GC-MS and LC-MS. The samples in different groups were distinguished and the differential metabolites were screened based on the VIP value, FC, and P-value of each comparison group through multivariate statistical analysis. The pathways related to differential metabolites were searched to reveal the effects of PFOA exposure on metabolic changes in pregnant women at different degrees. Finally, the ROC of differential metabolites was performed, and the differential metabolites with large area under the curve (AUC) values were selected and compared to identify the mutually differential metabolites. Meanwhile, these metabolites were fitted with a multivariable to explore if they could be used to distinguish different groups. The quantitative comparison of mutually differential metabolites revealed that the levels of L-cysteine, glycine, and 5-aminovaleric acid were positively correlated with the degree of PFOA exposure, indicating that different degrees of PFOA exposure could affect the synthesis or degradation of GSH and change the metabolism of oral or intestinal microbiota. Additionally, they may cause oxidative stress and abnormal fat metabolism in pregnant women. [ABSTRACT FROM AUTHOR]

Lung cancer is the most common primary malignant lung tumor. However, the etiology of lung cancer is still unclear. Fatty acids include short-chain fatty acids (SCFAs) and polyunsaturated fatty acids (PUFAs) as essential components of lipids. SCFAs can enter the nucleus of cancer cells, inhibit histone deacetylase activity, and upregulate histone acetylation and crotonylation. Meanwhile, PUFAs can inhibit lung cancer cells. Moreover, they also play an essential role in inhibiting migration and invasion. However, the mechanisms and different effects of SCFAs and PUFAs on lung cancer remain unclear. Sodium acetate, butyrate, linoleic acid, and linolenic acid were selected to treat H460 lung cancer cells. Through untargeted metabonomics, it was observed that the differential metabolites were concentrated in energy metabolites, phospholipids, and bile acids. Then, targeted metabonomics was conducted for these three target types. Three LC-MS/MS methods were established for 71 compounds, including energy metabolites, phospholipids, and bile acids. The subsequent methodology validation results were used to verify the validity of the method. The targeted metabonomics results show that, in H460 lung cancer cells incubated with linolenic acid and linoleic acid, while the content of PCs increased significantly, the content of Lyso PCs decreased significantly. This demonstrates that there are significant changes in LCAT content before and after administration. Through subsequent WB and RT-PCR experiments, the result was verified. We demonstrated a substantial metabolic disparity between the dosing and control groups, further verifying the reliability of the method. [ABSTRACT FROM AUTHOR]

Background: Esophageal squamous cell carcinoma (ESCC) is a deadly gastrointestinal malignancy, and chemotherapy resistance is a key factor leading to its poor prognosis. M2 tumor-associated macrophages (M2-TAMs) may be an important cause of chemoresistance in ESCC, but its exact mechanism is still unclear. Methods: In order to study the role of M2-TAMs in ESCC chemoresistance, CCK-8, clone formation assay, flow cytometric apoptosis assay, qRT-PCR, western blotting, and serum-free sphere formation assays were used. In vivo animal experiments and human ESCC tissues were used to confirm the findings. Results: In vitro and in vivo animal experiments, M2-TAMs reduced the sensitivity of ESCC cells to cisplatin. Mechanistically, M2-TAMs highly secreted TGF-β1 which activated the TGFβR1-smad2/3 pathway to promote and maintain the stemness characteristic of ESCC cells, which could inhibit the sensitivity to cisplatin. Using TGFβ signaling inhibitor SB431542 or knockdown of TGFβR1 could reverse the cisplatin resistance of ESCC cells. In 92 cases of human ESCC tissues, individuals with a high density of M2-TAMs had considerably higher levels of TGF-β1. These patients also had worse prognoses and richer stemness markers. Conclusion: TGF-β1 secreted from M2-TAMs promoted and maintained the stemness characteristic to induce cisplatin resistance in ESCC by activating the TGFβ1-Smad2/3 pathway. [ABSTRACT FROM AUTHOR]

This study evaluated the mediating role of social support in the relationships between mental health and academic achievement and used a sample of 640 college students from lower socioeconomic status (LSES) compared to 501 from higher socioeconomic status (HSES) in China. Self-report measures of depression, anxiety, Internet addiction, self-esteem, perceived social support, and grade point average (GPA) were measured online. Group differences were examined with Chi-square analyses. Results. (1) There were significant differences in mental health, academic achievement, and social support between LSES and HSES. (2) Anxiety, depression, and Internet addiction were significantly negatively correlated with academic achievement; self-esteem and social support were significantly positively correlated with academic achievement. (3) Social support has a mediating role between mental health and academic achievement. These results proved that it is necessary to pay more attention to their mental health and develop social support to improve their academic achievement for LSES students. Previous studies have paid little attention to the LSES students, but these students are more prone to psychological problems. Therefore, this study focuses on the LSES students. [ABSTRACT FROM AUTHOR]

The entrance and exit sections of a tunnel are the accident black-spots in an expressway. For a safe operation of road tunnels, it is necessary to understand a driver's physiological indices and driving performance when driving through tunnels. In this study, the UC-Win/Road simulation software was used to build 12 tunnel models of different lengths. A simulated driving experiment was carried out in a 6-DoF motion platform. The lateral position of vehicles characterizing the driving performance was measured using the motion platform. Electrocardiogram and eye movement data of 25 recruited drivers were collected simultaneously through the experiment. The spatial changes in a driver's heart rate (HR) growth rate, RMSSD, pupil diameter growth rate and vehicle lateral deviation within 300 m before and after the tunnel entrance and exit were analyzed to determine the variation rules in the different tunnels. The study identified the length range in the tunnel entrance and exit sections that influences the drivers. A quantitative analysis was further carried out to analyze the relationship between the physiological indices and the driving performance indicator. The results showed that a driver's heart rate fluctuates significantly 250 m before the tunnel entrance and 50 m before the exit. In this region, the pupil diameter increases gradually, and drivers tend to shift the vehicle to the left. At the tunnel exit, the HR and RMSSD are affected significantly by the tunnel length, and the variation is higher in longer tunnels. In comparison, the tunnel length has no significant effect on the physiological indicators and driving performance of the drivers at the entrance and exit. [ABSTRACT FROM AUTHOR]

Background: Increases in the levels of serum C-reactive protein (CRP) and creatinine (Cr) and decreases in those of albumin (Alb) are commonly observed in acute pancreatitis (AP). We aimed to evaluate the efficacy of the Cr/Alb and CRP/Alb ratios in the prediction of surgical treatment effect in AP patients.Methods: This study retrospectively analyzed clinical data obtained from 140 AP patients who underwent debridement from January 2008 to November 2018 in Shanghai Ruijin Hospital. The Cr/Alb and CRP/Alb ratios at admission and before surgery were assessed in the analysis of clinical statistics, prediction of prognoses, and logistic regression analysis.Results: The admission Cr/Alb had the best predictive value of the four ratios. This value was significantly higher in patients with re-operation and those who died (P < 0.05) and was correlated with the Acute Physiology and Chronic Health Evaluation (APACHE II) score, admission CRP/Alb, preoperative Cr/Alb, and post-operative complications. The admission Cr/Alb could predict the risk of AP-related re-operation and mortality with sensitivities, specificities and areas under the curve of 86.3%, 61.7% and 0.824, and 73.4%, 81.3% and 0.794, respectively. At a cut-off value of 3.43, admission Cr/Alb values were indicative of a worse clinical state, including impaired laboratory test values, APACHE II scores, rates of post-operative complications and re-operation, and mortality (P < 0.05). In the logistic regression analysis, admission Cr/Alb values were independently related to the APACHE II score, post-operative renal failure, and mortality.Conclusion: Cr/Alb is a novel but promising, easy-to-measure, reproducible, non-invasive prognostic score for the prediction of the effect of debridement in AP patients. [ABSTRACT FROM AUTHOR]

Stair-climbing posture is a common motion posture of lower extremity exoskeleton robots. In the process of climbing stairs, with the change of the gravity center of system, it has a direct impact on the dynamic stability characteristics of human-machine system. Based on this, a complete diagram of the stair-climbing posture can be set up, which can be divided into the starting stage, the intermediate stage and the ending stage. The foot trajectory, COG trajectory and ZMP trajectory of human-machine system in the intermediate stage of stair-climbing posture can be analyzed by drawing stair-climbing motion diagram of six-step. Based on the inverted pendulum theory, a virtual inverted pendulum model with variable height (VCHIPM) is proposed to analyze the influence of the change of the gravity center on the dynamic stability of the human-machine system in the upstairs posture. The test results show us that COG position can be changed by adjusting the value of a, so as to adjust the position of ZMP, reduce the error of ZMP and ensure the stability of human-machine system. [ABSTRACT FROM AUTHOR]

Cellulose pressboard is used as a key element in various power equipment insulation structures and determines the operational safety of electric equipment and power systems. This paper aims to increase the application of a pressboard aging assessment method based on frequency domain spectroscopy, a promising nondestructive method for power equipment diagnosis, through in-depth theoretical analysis and accurate data fitting. To achieve this purpose, first, based on classic theoretical models in the field of dielectric physics, a mathematical deduction is proposed to separate each dielectric process in the overlapping frequency band. Second, a novel analysis approach that considers both the pressboard dielectric response and the thermally stimulated current is proposed and demonstrated to be effective in determining the physical meaning of pressboard microscopic dielectric processes. Third, a function model based on a specific microscopic mechanism is established to fit the frequency domain spectra of pressboard samples with different aging degrees. Based on this approach, the variations in charge carrier motion characteristics in the frequency domain with increasing pressboard aging degree are clarified. Moreover, the function model provides characteristic parameters that are clearly related to the degree of polymerization of the material, which represents a quantitative method for evaluating the aging degree of cellulose pressboard by indirectly obtaining its frequency response curve. [ABSTRACT FROM AUTHOR]

The red imported fire ant, Solenopsis invicta Buren, is a serious agricultural and public health pest in its introduced range. Several natural products have been tested to replace synthetic insecticides for the novel, economically feasible and environmentally friendly control of this pest. No information is available on the toxicity of vitamins to red imported fire ants. This study examined the effects of l-ascorbic acid (vitamin C) on the survival and behavior of red imported fire ants. In a toxicity assay, l-ascorbic acid (l-AA, vitamin C) appeared to be the most toxic vitamin to S. invicta and caused significantly higher mortality of S. invicta than the control and other tested vitamins. Concentration- and exposure time-dependent mortality of ants was observed after feeding on different concentrations of l-AA. S. invicta equally preferred l-AA and sucrose solution and rapidly transferred l-AA by workers. Significant adverse effects on the necrophoric, recruiting and foraging behavior of this pest insect were observed after feeding on l-AA. The walking speed of l-AA-fed ants was significantly reduced; however, we observed no significant difference in mortality of ants during group aggression assays. When we examined the presence of l-AA in the hemolymph and excretion, unlike in the normal control, more l-AA was observed in the hemolymph of the workers that ingested 0.05/0.1 g/ml of l-AA solution after 48 h. However, there was no significant difference in the concentration of l-AA in the excretion. This study demonstrated that l-AA has negative effects on S. invicta and can be used as baits to provide a highly effective and environmentally sustainable method to control red imported fire ants. [ABSTRACT FROM AUTHOR]

A high efficiency capacitor-free low-dropout regulator (LDO) with the cross-couple class-AB push–pull input stage is presented for wireless internet of things and wireless senor network chip. Utilizing the proposed input stage, both load/line regulation and power supply rejection ratio (PSRR) are improved. Meanwhile, the transient response including the undershoot voltage, the overshoot voltage and the recovery time is optimized with the sub-threshold slew-rate enhancement circuit and the multiple loop compensation strategy. Simulation results show that the LDO only consumes a quiescent current of 41.8 μA, resulting in the energy efficiency of 99.96% at a 100-mA maximum load current (IL) from 1.2 V supply voltage using 0.18-μm CMOS process. When IL is switching from 0 A to 100 mA in 0.3 μs, the undershoot voltage and the overshoot voltage are about 131.62 mV and 126.31 mV while the corresponding recovery time are 0.77 μs and 0.55 μs with CL = 100 pF, respectively. Furthermore, PSRR at 1-kHz is boosted to − 58.8 dB at full load. Besides, an excellent line and load regulation of 0.24 mV/V and 1.76 μV/mA are obtained, respectively. [ABSTRACT FROM AUTHOR]

Attention maps have been fused in the VggNet structure (EAC-Net) [] and have shown significant improvement compared to that of the VggNet structure. However, in [], E-Net was designed based on the facial action unit (AU) center and for facial AU detection only. Thus, for the use of attention maps in every image type, this paper proposed a new convolutional neural network (CNN) structure, P_VggNet, comprising the following parts: P_Net and VggNet with 16 layers (VggNet-16). The generation approach of P_Net was designed, and the P_VggNet structure was proposed. To prove the efficiency of P_VggNet, we designed two experiments, which indicated that P_VggNet could more efficiently extract image features than VggNet-16. [ABSTRACT FROM AUTHOR]

Frequency domain spectroscopy is considered to be a promising and novel method for the assessment of the insulation condition of power equipment. This work has practical significance as it explains the microscopic mechanism of this method in a wide temperature range and further establishes its quantitative model. To achieve this, in the present paper, we select oil-impregnated paper—one of the most common insulation materials for power equipment with a complex microstructure—as a test sample, deduce a formula based on the relationship between the real and imaginary parts of the complex permittivity to extract the spectra of independent dielectric processes and measure the frequency domain spectra of oil-impregnated paper under different temperatures, as well as its thermally stimulated depolarization current with a series of bias voltages. The analysis results reveal that oil-impregnated paper's frequency domain spectra in a wide temperature range are mainly determined by dielectric processes whose generation mechanisms are low-frequency dispersion, DC conduction, electrode relaxation, interfacial relaxation and dipole relaxation, respectively. Moreover, due to the different thermal properties of charge motions, the macroscopic characteristics and microscopic generation mechanisms of both spectra vary significantly with the sample's temperature. After verifying the generation mechanisms of the spectra in high, middle and low-temperature ranges, function models for those spectra with clear physical meanings are established separately, providing sufficient physical parameters to carry out insulation assessment. [ABSTRACT FROM AUTHOR]