[Protective effect and mechanism of Astragalus membranaceus and Angelica sinensis compatibility against triptolide-induced hepatotoxicity by regulating Keap1/Nrf2/PGC-1α].

This paper aims to investigate the protective effect and mechanism of Astragalus membranaceus and Angelica sinensis before and after compatibility against triptolide(TP)-induced hepatotoxicity. The experiment was divided into a blank group, model group, Astragalus membranaceus group, Angelica sinensis group, and compatibility groups with Astragalus membranaceus/Angelica sinensis ratio of 1∶1, 2∶1, and 5∶1. TP-induced hepatotoxicity model was established, and corresponding drug intervention was carried out. The levels of alanine transaminase(ALT), aspartate transaminase(AST), and alkaline phosphatase(ALP) in serum were detected. Pathological injuries of livers were detected by hematoxylin-eosin(HE) staining. The levels of malondialdehyde(MDA), superoxide dismutase(SOD), glutathione peroxidase(GSH-Px), and reduced glutathione(GSH) in the liver were measured. Wes-tern blot method was used to detect the expression of nuclear factor erythroid 2-related factor 2(Nrf2), Kelch-like ECH-associated protein 1(Keap1), peroxisome proliferator-activated receptor gamma, coactivator-1 alpha(PGC-1α), heme oxygenase-1(HO-1), and NAD(P)H quinone dehydrogenase 1(NQO1) in livers. Immunofluorescence was used to detect the expression of Nrf2 and PGC-1α in livers. The results indicated that Astragalus membranaceus/Angelica sinensis ratio of 2∶1 and 5∶1 could significantly reduce the levels of serum AST, ALT, and ALP, improve the pathological damage of liver tissue, increase the levels of GSH and GSH-Px, and reduce the content of MDA in liver tissue. Astragalus membranaceus/Angelica sinensis ratio of 1∶1 and 2∶1 could significantly improve the level of SOD. Astragalus membranaceus and Angelica sinensis before and after compatibility significantly increased the protein expression of HO-1 and NQO1, improved the protein expression of Nrf2 and PGC-1α, and decreased the protein expression of Keap1 in liver tissue. The above results confirmed that the compatibility of Astragalus membranaceus and Angelica sinensis had antioxidant effects by re-gulating Keap1/Nrf2/PGC-1α, and the Astragalus membranaceus/Angelica sinensis ratio of 2∶1 and 5∶1 had stronger antioxidant effect and significantly reduced TP-induced hepatoto-xicity.

ox-LDL induces autophagy-mediated apoptosis by suppressing secretagogin-regulated autophagic flux in pancreatic ß-cells.

Lipotoxicity has been shown to induce the loss of functional ß-cell mass and lead to type 2 diabetes, but the mechanism remains unknown. In this study, we aim to explore the role of secretagogin (SCGN) in lipotoxicity-induced ß-cell injury. Our results indicate that ox-LDL treatment leads to autophagic cell death, as evidenced by decreased cell viability, aggravated cell apoptosis, and the accumulation of the p62 protein in MIN6 cells. LysoTracker Red staining, TEM and mRFP-GFP-LC3 assays demonstrate that autophagic flux is blocked in ox-LDL-treated MIN6 cells. Intriguingly, SCGN is significantly decreased in MIN6 cells under lipotoxic conditions. Additionally, siRNA-guided SCGN knockdown blocks autophagic flux triggered by rapamycin, while SCGN restoration alleviates autophagic flux retardation and mitigates cell apoptosis. The physical interaction between SCGN and SNAP29 is validated by bioinformatics analysis, coimmunoprecipitation assay and SCGN knockdown test. Downregulation of SCGN expression reduces the interaction of these two proteins. Taken together, our results indicate that ox-LDL treatment induces apoptotic ß-cell death by blocking autophagic flux dependent on SCGN downregulation. SCGN administration prevents lipotoxic ß-cell injury and may be a potential therapeutic strategy to promote ß-cell expansion in type 2 diabetes.

Entrepreneurial responses to uncertainties during the COVID-19 recovery: A longitudinal study of B&Bs in Zhangjiajie, China.

The COVID-19 pandemic has brought sweeping changes to global tourism alongside large-scale travel restrictions, posing complex challenges to entrepreneurs and firms seeking to find their footing in a turbulent climate. This study presents a theoretical framework linking uncertainty, capital, and innovation to analyse how bed-and-breakfast small and medium-sized enterprises have innovatively responded to unprecedented obstacles during COVID-19 recovery. Three-stage longitudinal interviews were conducted with more than 30 entrepreneurs between April and November 2020 to unpack their ongoing responses to the pandemic. The recovery process was found to be non-linear due to the shifting nature of sources of uncertainty and changes in entrepreneurs' capital. These alterations shaped interviewees' responses, especially in terms of product and marketing innovations, which ultimately generated new uncertainty.

Antibodies against atypical pathogens and respiratory viruses detected by Pneumoslide IgM test in adults with community-acquired pneumonia in Guangzhou City.

BACKGROUND: To detect the serum antibodies against respiratory viruses and atypical pathogens in adults with community-acquired pneumonia (CAP) in Guangzhou City (Guangdong province, China). METHODS: A retrospective study was carried out with samples from 685 adults who were admitted with CAP and 108 non-CAP control patients. Atypical pathogens and respiratory viruses in serum were detected using the Pneumoslide IgM test from Vircell, Spain. All patients were divided into 6 groups according to age: 18-24, 25-44, 45-59, 60-74, 75-89, and >90. RESULTS: The total positive rate of CAP was 35.4%, which was highest in the 18-24 age group (P < .05). The highest positive rate, 17.11%, was observed for Mycoplasma pneumoniae (MP). The mean age of MP-infected patients was higher than that of the controls (P < .05). The positive rates for influenza B (INFB), Legionella pneumophila (LP1), Coxiella burnetii (COX), influenza A (INFA), parainfluenza virus (PIV), respiratory syncytial virus (RSV), Chlamydophila pneumoniae (CP), and adenovirus (ADV) were 5.56%, 3.07%, 2.63%, 2.34%, 1.90%, 1.61, 0.88%, and 0.29%, respectively. There were 4.37% of patients with CAP having multiple infections. The main symptoms observed in the 685 CAP patients were cough and sputum production, in 78.4% and 67.4%. Fever was followed by 54% of CAP patients. Dyspnea (39.1%), anorexia (36.8%), increased thirst (26.7%), chills (18.7), headache (14.6%), and nausea (13.1%) were also frequently observed in the CAP patients. CONCLUSIONS: MP infection was the most common in adult CAP patients in Guangzhou City with the highest positive rate in the 18-24 age groups.

Promoter Variation and Gene Expression of mcr-1-Harboring Plasmids in Clinical Isolates of Escherichia coli and Klebsiella pneumoniae from a Chinese Hospital.

Next-generation sequencing of 6 mcr-1-harboring Escherichia coli and Klebsiella pneumoniae isolates collected from a tertiary care hospital in China revealed significant sequence variations in the regions flanking the mcr-1 gene. While sequence variations significantly affected the expression and promoter activity of mcr-1, the mcr-1 gene expression levels did not correlate with the in vitro colistin resistance levels, which warrants further in-depth investigations.

Direct Detection and Identification of Bacterial Pathogens from Urine with Optimized Specimen Processing and Enhanced Testing Algorithm.

Rapid and accurate detection and identification of microbial pathogens causing urinary tract infections allow prompt and specific treatment. We optimized specimen processing to maximize the limit of detection (LOD) by matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS) and evaluated the capacity of combination of MALDI-TOF MS and urine analysis (UA) for direct detection and identification of bacterial pathogens from urine samples. The optimal volumes of processed urine, formic acid/acetonitrile, and supernatant spotted onto the target plate were 15 ml, 3 µl, and 3 µl, respectively, yielding a LOD of 1.0 × 105 CFU/ml. Among a total of 1,167 urine specimens collected from three hospital centers, 612 (52.4%) and 351 (30.1%) were, respectively, positive by UA and urine culture. Compared with a reference method comprised of urine culture and 16S rRNA gene sequencing, the sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of MALDI-TOF MS alone and MALDI-TOF MS coupled with UA were 86.6% versus 93.4% (χ2 = 8.93; P < 0.01), 91.5% versus 96.3% (χ2 = 7.06; P < 0.01), 81.5% versus 96.4% (χ2 = 37.32; P < 0.01), and 94.1% versus 93.1% (χ2 = 0.40; P > 0.05), respectively. No significant performance differences were revealed among the three sites, while specificity and NPV of MALDI-TOF MS for males were significantly higher than those for females (specificity, 94.3% versus 77.3%, χ2 = 44.90, P < 0.01; NPV, 95.5% versus 86.1%, χ2 = 18.85, P < 0.01). Our results indicated that the optimization of specimen processing significantly enhanced analytical sensitivity and that the combination of UA and MALDI-TOF MS provided an accurate and rapid detection and identification of bacterial pathogens directly from urine.

[Study on Non-Detective Determination of ß-Carotene Content in Loquats with Raman Spectroscopy].

In china, researches on Raman spectroscopy in terms of foodstuff mainly focus on carbohydrates, fatty acids, proteins and vitamins. Conventional methods for determining the carotenoids content require the extraction of the samples as well as other cleanup steps. In this work, Raman spectroscopy is applied to get the measured value form loquats with different mature stage which are compared with the reference value get from High Performance Liquid Chromatography (HPLC)，in order to find new, fast, and nondestructive calibration methods for quantification of ß-carotene content in loquat fruits. Least Squares Support Vector Machine and Partial least squares data processing methods are used to analyze the Raman spectra while PLS model has a prediction quality with the correlation coefficient of 0.845; the root-mean-square error of 0.022 µg·g(-1) and LS-SVM model has a better prediction quality with the correlation coefficient of 0.910 with the root-mean-square error of 0.058 µg·g(-1).

[Study on Visual Identification of Corn Seeds Based on Hyperspectral Imaging Technology].

The seed purity is an important indicator of seed quality. The paper proposes a visual identification method of corn seed based on the near-infrared (874~1,734 nm) hyperspectral image technology. Hyperspectral image data of 4 cultivars of a total of 384 corn seed samples will be acquired. Then 288 of samples are to be selected randomly as the calibration set, and the remaining 96 samples will be used for the prediction set. After inspection of the near-infrared spectral curves, 7 effective wavelengths (EWs) are to be selected by successive projection algorithm (SPA). And then 7 EWs of the calibration set will be used as input to build a partial least squares (PLS) model. Good results are to be obtained with Rc = 0.917 7, RMSECV = 0.444 2; Rcv = 0.911 5, RMSECV = 0.459 9. And the total identification rate of the developed PLS model will be 78.5% for the calibration set and 70.8% for the prediction set. Finally, average spectral data of each corn seed in a hyperspectral image will be extracted by image process technology, and used as input of the developed SPA-PLS model. In the produced identification map, different colors are to be used to represent different predicted cultivars. 3 mixture samples of corn seeds will be identified, and help to achieve satisfied visual effects. The result indicates that, by means of the visual identification technology we could intuitively observe the distribution of corn seeds of different cultivars in mixture samples. The research provides help for the identification and screening of seeds in agricultural production.

Unraveling the link between hypertriglyceridemia, dampness syndrome, and chronic diseases: A comprehensive observational study.

To investigate the dampness syndrome score in hypertriglyceridemia and the correlations between hypertriglyceridemia and other chronic diseases and lifestyle factors. Data were retrospectively obtained from individuals who underwent physical examinations at Guangzhou Cadres Health Management Centre from May 2022 to May 2023. t Test, variance analysis, and chi-square test were used to compare the score of dampness syndrome and the prevalence of hypertriglyceridemia among different subgroups. Pearson, Spearman correlation analysis, and regression analysis were used to explore the correlations between hypertriglyceridemia and dampness syndrome, chronic diseases, and lifestyle factors. The prevalence of hypertriglyceridemia was 26.70%. Clinical test index and dampness syndrome score were significant differences between hypertriglyceridemia group and normal group (P < .05). Subgroup analyses as a function of the degree of triglyceridemia indicated that the dampness syndrome score increased with increasing degree of triglyceridemia (P < .05). Correlation analysis showed that hypertriglyceridemia was correlated with dampness syndrome, overweight/obesity, hypertension, diabetes, and other chronic diseases (P < .05). Multivariate logistic regression analysis showed that age, sex, marriage, education level, smoking, drinking, fruit consumption, vegetable consumption, milk and dairy product consumption, dessert or snack consumption, the degree of dampness syndrome, and engagement in exercise were associated with hypertriglyceridemia (P < .05). Hypertriglyceridemia is associated with a variety of chronic diseases and lifestyle factors, and is closely related to dampness syndrome. The score of dampness syndrome can reflect hypertriglyceridemia to a certain extent. It provides more clinical reference for the treatment of hypertriglyceridemia combined with the analysis of dampness syndrome of traditional Chinese medicine.

Characterization of tongue coating microbiome from patients with colorectal cancer.

Background: Tongue coating microbiota has aroused particular interest in profiling oral and digestive system cancers. However, little is known on the relationship between tongue coating microbiome and colorectal cancer (CRC). Methods: Metagenomic shotgun sequencing was performed on tongue coating samples collected from 30 patients with CRC, 30 patients with colorectal polyps (CP), and 30 healthy controls (HC). We further validated the potential of the tongue coating microbiota to predict the CRC by a random forest model. Results: We found a greater species diversity in CRC samples, and the nucleoside and nucleotide biosynthesis pathway was more apparent in the CRC group. Importantly, various species across participants jointly shaped three distinguishable fur types.The tongue coating microbiome profiling data gave an area under the receiver operating characteristic curve (AUC) of 0.915 in discriminating CRC patients from control participants; species such as Atopobium rimae, Streptococcus sanguinis, and Prevotella oris aided differentiation of CRC patients from healthy participants. Conclusion: These results elucidate the use of tongue coating microbiome in CRC patients firstly, and the fur-types observed contribute to a better understanding of the microbial community in human. Furthermore, the tongue coating microbiota-based biomarkers provide a valuable reference for CRC prediction and diagnosis.

The clinical significance comparison of a latex agglutination based syphilis screening test at low antibody titer.

The rapid increase of syphilis underscores a tremendous need to carefully evaluate many new serological tests for syphilis and choose efficient and economical strategies for syphilis screening, especially in the case of primary infection with low antibody titer. Between 2011 and 2012, 73 patients' sera samples were included in this retrospective study. They were either TRUST or TPPA reactive, either LA (latex agglutination) based auto3 TP or CLIA (chemiluminescence assay) based Architect Syphilis TP assay reactive. The contradictory weak response samples were further examined by FTA-Abs method. TPPA could not give reactive results in samples with antibody concentration less than 10 mIU. Auto3 TP reagent shows good linearity at low antibody titers and was more sensitive than TPPA, while the former does not show significant superiority compared to the Architect Syphilis TP assay at low antibody titer, except that it is suitable for adaptation on diverse automated chemistry analyzers.

Uric acid en route to gout.

Gout and hyperuricemia (HU) have generated immense attention due to increased prevalence. Gout is a multifactorial metabolic and inflammatory disease that occurs when increased uric acid (UA) induce HU resulting in monosodium urate (MSU) crystal deposition in joints. However, gout pathogenesis does not always involve these events and HU does not always cause a gout flare. Treatment with UA-lowering therapeutics may not prevent or reduce the incidence of gout flare or gout-associated comorbidities. UA exhibits both pro- and anti-inflammation functions in gout pathogenesis. HU and gout share mechanistic and metabolic connections at a systematic level, as shown by studies on associated comorbidities. Recent studies on the interplay between UA, HU, MSU and gout as well as the development of HU and gout in association with metabolic syndromes, non-alcoholic fatty liver disease (NAFLD), and cardiovascular, renal and cerebrovascular diseases are discussed. This review examines current and potential therapeutic regimens and illuminates the journey from disrupted UA to gout.

Dysbiosis of the gut microbiome in elderly patients with hepatocellular carcinoma.

Fecal samples from participants aged 60-80 were collected and sequenced by a high-throughput second-generation sequencer to explore the structural composition of gut microbiota in elderly patients with hepatocellular carcinoma(HCC). Comparison of gut microbiota between patients with hepatocellular carcinoma and healthy controls, α diversity and ß diversity were statistically different. At the genus level, compared with the normal group, the abundance of A Blautia, Fusicatenibacter, Anaerostipes, Lachnospiraceae_ND3007_group, CAG-56, Eggerthella, Lachnospiraceae_FCS020_group and Olsenella were decreased significantly in the LC group. In contrast, the abundance of Escherichia-Shigella, Fusobacterium, Megasphaera, Veillonella, Tyzzerella_4, Prevotella_2 and Cronobacter increased significantly. The KEGG and COG pathway analyses showed that the dysbiosis of gut bacteria in primary liver carcinoma is associated with several pathways, including amino acid metabolism, replication and repair, nucleotide metabolism, cell motility, cell growth and death, and transcription. Age is negatively associated with the abundance of Bifidobacterium. Lachnospiraceae_ ND3007_ group, [Eubacterium]_hallii_group, Blautia, Fuscatenibacter and Anaerostipes are negatively correlated with ALT, AST and GGT levels (p < 0.05), respectively. Alpha-fetoprotein (AFP) is positively associated with the abundance of Erysipelatoclostridium, Magasphaera, Prevotella 2, Escherichia-Shigella, Streptococcus and [Eubacterium]_eligens_group (p < 0.05), respectively. A random forest model showed that the genera Eggerthella, Anaerostipes, and Lachnospiraceae_ ND3007_ group demonstrated the best predictive capacity. The area under the Receiver Operating Characteristic Curve of Eggerthella, Anaerostipes and Lachnospiraceae_ ND3007_ group are 0.791, 0.766 and 0.730, respectively. These data are derived from the first known gut microbiome study in elderly patients with hepatocellular carcinoma. Potentially, specific microbiota can be used as a characteristic index for screening, diagnosis, and prognosis of gut microbiota changes in elderly patients with hepatocellular carcinoma and even as a therapeutic clinical target.

Efficacy and safety of Camrelizumab combined with Abraxane + lobaplatin regimen for advanced gastric cancer.

PURPOSE: To examine the safety and effectiveness of the combination of Camrelizumab and Abraxane + lobaplatin in advanced gastric cancer therapy. METHODS: The data of 60 patients with advanced gastric cancer in Shaanxi Provincial People's Hospital from May 2017 to March 2019 were analyzed retrospectively. The patients were divided into a study group (n=30) and a control group (n=30) according to different treatment methods. The study group received Camrelizumab combined with the Abraxane + lobaplatin regimen, and the control group received the Abraxane + lobaplatin regimen only. The levels of soluble interleukin-2 receptor (sIL-2R), secretory glycoprotein (Dickkopf-1, DKK-1) and tumor specific growth factors (TSGFs), the relative molecular expression of serum miRNA-1290, miRNA-647 and miRNA-182, and the Karnofsky performance status (KPS) were compared between the two groups. The adverse reactions of the two groups were observed, and the 3-year survival rates were compared. RESULTS: The disease control rate and overall remission rate of the study group (53.33%, 90.00%) were higher than those of the control group (26.67%, 50.00%), with statistically significant differences (P<0.05). The levels of sLL-2R, DKK-1 and TSGF were reduced in both groups (P<0.05) after being treated, whereas these were comparatively lower levels in the study group (P<0.05). After treatment, serum concentration of miRNA-1290, miRNA-647 and miRNA-182 were lower in the study group than in the control group (P<0.05). Upon comparison with those in the control group, the KPS scores were higher at 1, 3 and 6 months after treatment in the study group (P<0.05). The incidence of adverse events was not significantly different between the two groups (P>0.05). The 1-year, 2-year and 3-year survival rates were higher in the study group (57.38%, 39.34% and 29.51%) than in the control group (32.79%, 18.03% and 8.20%) (P<0.05). CONCLUSION: The combination of Camrelizumab and Abraxane + lobaplatin is an effective treatment for advanced gastric cancer and can increase the patient's survival rate.

Phosphorus conditions change the cellular responses of Microcystis aeruginosa to perfluorooctanoic acid.

Perfluorooctanoic acid (PFOA), a widespread and emerging organic contaminant of aquatic environments, has high bioaccumulation potential and high toxicity. Consequently, major concerns have been raised worldwide regarding the management of this pollutant in aquatic ecosystems. To thoroughly understand PFOA's toxic effects on aquatic organisms, systematic investigations were conducted on the cellular responses of Microcystis aeruginosa to the environmental concentrations of PFOA under various concentrations as well as phosphorus (P) conditions (concentrations and forms). The results showed that P conditions remarkably affected cyanobacterial growth as well as photosynthetic pigment content, triggered oxidative stress to disrupt the function and structure of the cell membrane, and caused changes in the extracellular and intracellular contents of microcystin-LR (MC-LR). Furthermore, PFOA (100 µg/L) was absorbed by cyanobacterial cells through the stimulation of the secretion of extracellular polymeric substances (EPS) by M. aeruginosa. After entering the cyanobacterial cells, PFOA inhibited photosynthesis, reduced P absorption, induced oxidative damage, lead to a loss of cell integrity evident in scanning electron microscope images, and increased mcyA gene expression to promote MC-LR production. Moreover, the limited P concentration and forms conditions led to increased PFOA absorption by cyanobacterial cells, which further upregulated mcyA gene expression and increased the risk of MC-LR diffusion into the aquatic environment. Our present study provided a theoretical basis and new ideas for understanding and addressing safety issues related to the presence of PFOA in aquatic environments with varying nutritional statuses.

Quorum sensing N-acyl homoserine lactones-SdiA enhances the biofilm formation of E. coli by regulating sRNA CsrB expression.

As an important virulence phenotype of Escherichia coli, the regulation mechanism of biofilm by non-coding RNA and quorum sensing system has not been clarified. Here, by transcriptome sequencing and RT-PCR analysis, we found CsrB, a non-coding RNA of the carbon storage regulation system, was positively regulated by the LuxR protein SdiA. Furthermore, ß-galactosidase reporter assays showed that SdiA enhanced promoter transcriptional activity of csrB. The consistent dynamic expression levels of SdiA and CsrB during Escherichia coli growth were also detected. Moreover, curli assays and biofilm assays showed sdiA deficiency in Escherichia coli SM10λπ or BW25113 led to a decreased formation of biofilm, and was significantly restored by over-expression of CsrB. Interestingly, the regulations of SdiA on CsrB in biofilm formation were enhanced by quorum sensing signal molecules AHLs. In conclusion, SdiA plays a crucial role in Escherichia coli biofilm formation by regulating the expression of non-coding RNA CsrB. Our study provides new insights into SdiA-non-coding RNA regulatory network involved in Escherichia coli biofilm formation.

Lane-GAN: A Robust Lane Detection Network for Driver Assistance System in High Speed and Complex Road Conditions.

Lane detection is an important and challenging part of autonomous driver assistance systems and other advanced assistance systems. The presence of road potholes and obstacles, complex road environments (illumination, occlusion, etc.) are ubiquitous, will cause the blur of images, which is captured by the vision perception system in the lane detection task. To improve the lane detection accuracy of blurred images, a network (Lane-GAN) for lane line detection is proposed in the paper, which is robust to blurred images. First, real and complex blur kernels are simulated to construct a blurred image dataset, and the improved GAN network is used to reinforce the lane features of the blurred image, and finally the feature information is further enriched with a recurrent feature transfer aggregator. Extensive experimental results demonstrate that the proposed network can get robust detection results in complex environments, especially for blurred lane lines. Compared with the SOTA detector, the proposed detector achieves a larger gain. The proposed method can enhance the lane detail features of the blurred image, improving the detection accuracy of the blurred lane effectively, in the driver assistance system in high speed and complex road conditions.

A low-light image enhancement method with brightness balance and detail preservation.

This paper proposes a new method for low-light image enhancement with balancing image brightness and preserving image details, this method can improve the brightness and contrast of low-light images while maintaining image details. Traditional histogram equalization methods often lead to excessive enhancement and loss of details, thereby resulting in an unclear and unnatural appearance. In this method, the image is processed bidirectionally. On the one hand, the image is processed by double histogram equalization with double automatic platform method based on improved cuckoo search (CS) algorithm, where the image histogram is segmented firstly, and the platform limit is selected according to the histogram statistics and improved CS technology. Then, the sub-histograms are clipped by two platforms and carried out the histogram equalization respectively. Finally, an image with balanced brightness and good contrast can be obtained. On the other hand, the main structure of the image is extracted based on the total variation model, and the image mask with all the texture details is made by removing the main structure of the image. Eventually, the final enhanced image is obtained by adding the mask with texture details to the image with balanced brightness and good contrast. Compared with the existing methods, the proposed algorithm significantly enhances the visual effect of the low-light images, based on human subjective evaluation and objective evaluation indices. Experimental results show that the proposed method in this paper is better than the existing methods.

Experimental investigation of heat transfer for diesel spray impingement on a high temperature wall.

In this paper, the heat transfer characteristics of spray-wall impingement on a high temperature wall were studied by using a transient thermocouple and a one-dimensional finite-difference conduction model to obtain variations of wall temperature and heat flux. Results showed that increasing the injection pressure and decreasing the ambient temperature both caused an increase in surface heat flux and heat transfer coefficient. However, with the increase of the initial surface temperature from 200 to 600 °C, the surface heat flux and heat transfer coefficient first increased and then decreased, and reached the maximum at about 520 °C and 390 °C respectively, which was due to the change of heat transfer regime on the wall. The contribution of experimental factors descended in the order of initial surface temperature, injection pressure and ambient temperature. The dimensionless surface heat fluxes in terms of Biot and Fourier numbers were highly similar and a dimensionless correlation was developed to quantify this heat transfer behavior, which showed that the ratio of the thermal resistance of the high temperature wall to the thermal resistance of convection heat transfer on the wall surface changed almost linearly during the process of spray-wall impingement.

Rheological Properties and Early-Age Microstructure of Cement Pastes with Limestone Powder, Redispersible Polymer Powder and Cellulose Ether.

In order to study the synergistic effects of organic and inorganic thickening agents on the rheological properties of cement paste, the rheological parameters, thixotropy cement-paste containing limestone powder (LP), re-dispersible polymer powder (RPP), and hydroxypropyl methylcellulose ether (HPMC) were investigated using the Anton Paar MCR 102 rheometer at different resting times. The early-age hydration process, hydration products, and microstructure were also analyzed with scanning electron microscopy (SEM) and thermogravimetry analyses (TGA). The results showed that the addition of LP, RPP, and HPMC affected the rheological properties of cement paste, but the thickening mechanism between organic and inorganic thickening agents was different. The small amount of LP increased the plastic viscosity but decreased the yield stress of cement paste due to its dense filling effect. Adding 1% of RPP improved the thixotropic property of cement paste by 50%; prolonging the standing time could improve the thixotropic performance by as much as two times. Only 0.035% HPMC added to the cement paste increased the plastic viscosity by 20%, while the yield stress increased nearly twice. The more HPMC added, the more significant effect it showed. Cement paste compounds with LP, RPP, and HPMC balanced the yield stress and plastic viscosity and improved the thixotropy. The C-L6-R1.0-H0.035 paste presented as a pseudoplastic, its rheological indexes were close to one, and it was hardly affected by the resting time. The composite superposition effect of organic and inorganic thickening agents reduced the impact of resting time for all pastes. As the organic thickening component inhibited the hydration more than the LP promoted the hydration of the cement paste, indicating that the C-L6-R1.0-H0.035 paste remained in the particle fusion stage after curing for three days, as shown by the SEM images.