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In undrained triaxial tests, membrane penetration varies with the change of effective confining pressure. Membrane compliance correction is a necessary step to accurately obtain the dynamic characteristics of soils in geotechnical tests. In this paper, a real-time instrument compensation equipment was adopted to eliminate membrane compliance The influence of membrane compliance on pore pressure was explained from experimental perspective, and a two-stage formula was proposed to establish the relationship between the optimized membrane correction coefficient Cm and the normalized pore pressure U/σ0′. C, which is the constant value of Cm in the stationary segment, is analyzed under different confining pressures, relative densities, consolidation ratios, and gravel contents, and the power function of C with the characteristic particle size d50 is proposed. Based on Cm, a series of predictions of pore pressure development without membrane compliance are implemented, which are basically consistent with the actual experimental results. The method to predict the pore pressure development without membrane compliance based on Cm is accurate and effective, and a large amount of experimental workload can be reduced for practical engineering applications. [ABSTRACT FROM AUTHOR]

In undrained triaxial tests, membrane penetration varies with the change of effective confining pressure. Membrane compliance correction is a necessary step to accurately obtain the dynamic characteristics of soils in geotechnical tests. In this paper, a real-time instrument compensation equipment was adopted to eliminate membrane compliance The influence of membrane compliance on pore pressure was explained from experimental perspective, and a two-stage formula was proposed to establish the relationship between the optimized membrane correction coefficient Cm and the normalized pore pressure U/σ0′. C, which is the constant value of Cm in the stationary segment, is analyzed under different confining pressures, relative densities, consolidation ratios, and gravel contents, and the power function of C with the characteristic particle size d50 is proposed. Based on Cm, a series of predictions of pore pressure development without membrane compliance are implemented, which are basically consistent with the actual experimental results. The method to predict the pore pressure development without membrane compliance based on Cm is accurate and effective, and a large amount of experimental workload can be reduced for practical engineering applications. [ABSTRACT FROM AUTHOR]

Amyloid beta 42 (A[[beta].sub.1-42])-induced oxidative stress causes the death of neuronal cells and is involved in the development of Alzheimer's disease. Oxymatrine (OMT) inhibits oxidative stress. In this study, we investigated the effect of OMT on A[[beta].sub.1-42]induced neurotoxicity in vivo and in vitro. In the Morris water maze test, OMT significantly decreased escape latency and increased the number of platform crossings. In vitro, OMT markedly increased cell viability and superoxide dismutase activity. Moreover, OMT decreased lactate dehydrogenase leakage, malondialdehyde content, and reactive oxygen species in a dosedependent manner. OMT upregulated the ratio of Bcl-2/Bax and downregulated the level of caspase-3. Furthermore, OMT inhibited the activation of MAP kinase (ERK 1/2, JNK) and nuclear factor [kappa]B. In summary, OMT may potentially be used in the treatment of Alzheimer's disease.Key words: oxymatrine, Alzheimer's disease, oxidative stress, neuroprotection, memory impairment, MAPK, NF-[kappa]B.Le stress oxydatif qu'engendre le peptide amyloide beta 42 (A[[beta].sub.1-42]) entraine la mort des cellules neuronales, processus jouant un role dans l'apparition de la maladie d'Alzheimer. Par ailleurs, l'oxymatrine (OMT) entraine une inhibition du stress oxydatif. Dans ces travaux, nous avons etudie l'effet de l'OMT sur la neurotoxicite qu'engendre l'A[[beta].sub.1-42] in vivo et in vitro. Dans le test de piscine de Morris, l'OMT entrainait une diminution notable de la latence d'evasion avec une augmentation du nombre de traversees de plateforme. In vitro, l'OMT entrainait une augmentation marquee de la vitalite cellulaire et de l'activite de la superoxyde dismutase. De plus, l'OMT entrainait une diminution de la fuite de deshydrogenase lactique, ainsi que des taux de malondialdehyde et des derives reactifs de l'oxygene de maniere proportionnelle a la dose. L'OMT entrainait une regulation a la hausse du ratio Bcl-2/Bax avec une regulation a la baisse des taux de caspase-3. En outre, l'OMT entrainait une inhibition de l'activation de la MAP kinase (ERK 1/2, JNK) et du facteur nucleaire [kappa]B. En resume, l'OMT pourrait eventuellement etre utilise dans le traitement de la maladie d'Alzheimer. [Traduit par la Redaction]Mots-cles : oxymatrine, maladie d'Alzheimer, stress oxydatif, neuroprotection, trouble de la memoire, MAPK, NF-[kappa]B., IntroductionOxidative stress is caused by an imbalance between the oxidative and antioxidant systems in the brain (Dal Santo et al. 2014). The overproduction of reactive oxygen species (ROS) is the [...]

Immunogenic cell death (ICD) has been increasingly indicated to be related to caners. However, ICD's role in Lung adenocarcinoma (LUAD) is still not well investigated. Clinical data along with associated mRNA expression profiles from LUAD cases were collected in TCGA and GEO databases. 13 ICD-related genes were identified. Relations of ICD-related genes expression with prognosis of patients, tumor immune microenvironment (TIME) was analyzed. Then, candidate genes were identified and the prognostic signature were constructed. Afterwards, one nomogram incorporating those chosen clinical data together with risk scores were built. Finally, the effect of HSP90AA1, one gene of the prognostic signature, on LUAD cell were analyzed. Two clusters were identified, which were designated as the ICD-high or -low subtype according to ICD-related genes levels. ICD-high subgroup showed good prognosis, high immune cell infiltration degrees, and enhanced immune response signaling activity compared with ICD-low subtype. Moreover, we established and verified the risk signature based on ICD-related genes. High risk group predicted poor prognosis of LUAD independently and presented negative association with immune score and immune status. Furthermore, nomogram contributed to the accurate prediction of LUAD prognostic outcome. Finally, HSP90AA1 levels were remarkably elevated within tumor cells in comparison with healthy pulmonary epithelial cells. HSP90α, HSP90AA1 protein product, promoted growth, migration, and invasion of LUAD cells. Molecular subtypes and prognostic model were identified by incorporating ICD-related genes, and it was related to TIME and might be adopted for the accurate prediction of LUAD prognosis. [ABSTRACT FROM AUTHOR]

Urban space architectural color is the first feature to be perceived in a complex vision beyond shape, texture and material, and plays an important role in the expression of urban territory, humanity and style. However, because of the difficulty of color measurement, the study of architectural color in street space has been difficult to achieve large-scale and fine development. The measurement of architectural color in urban space has received attention from many disciplines. With the development and promotion of information technology, the maturity of street view big data and deep learning technology has provided ideas for the research of street architectural color measurement. Based on this background, this study explores a highly efficient and large-scale method for determining architectural colors in urban space based on deep learning technology and street view big data, with street space architectural colors as the research object. We conducted empirical research in Jiefang North Road, Tianjin. We introduced the SegNet deep learning algorithm to semantically segment the street view images, extract the architectural elements and optimize the edges of the architecture. Based on K-Means clustering model, we identified the colors of the architectural elements in the street view. The accuracy of the building color measurement results was cross-sectionally verified by means of a questionnaire survey. The validation results show that the method is feasible for the study of architectural colors in street space. Finally, the overall coordination, sequence continuity, and primary and secondary hierarchy of architectural colors of Jiefang North Road in Tianjin were analyzed. The results show that the measurement model can realize the intuitive expression of architectural color information, and also can assist designers in the analysis of architectural color in street space with the guidance of color characteristics. The method helps managers, planners and even the general public to summarize the characteristics of color and dig out problems, and is of great significance in the assessment and transformation of the color quality of the street space environment. [ABSTRACT FROM AUTHOR]

Diabetes is mainly caused by abnormal increase of blood glucose level, the corresponding glucose sensor can be used to monitor the concentration of glucose. TiO2/NiOOH composite sensor was prepared by a facile method of electrodeposition of NiOOH on TiO2 nanotube arrays (TNT), and triangle Ag sheets modified by photodeposition. The structures and photoelectric properties were characterized by electrochemical workstation. It was found that NiOOH could effectively improve the photoelectrochemical properties of TNT. When Ag was further photodeposited on TNT/NiOOH, the photocurrent density improved at 0.21 mA/cm2. The enhanced photoelectrochemical properties can be attributed to the extended visible light absorption and effective separation of photo-generated carriers by the synergistic effect of Ag and NiOOH. The modified TNT/NiOOH exhibited much stronger photoelectrochemical reduction property toward glucose in comparison to pure TNT. The sensitivity of TNT/NiOOH/Ag to glucose can reach 2490 μA·cm−2·mM−1 and its detection limit low to 0.44 μM. [ABSTRACT FROM AUTHOR]

Characterizing natural mercury (Hg) isotopic compositions in geological and environmental matrices provides a better understanding of the biogeochemical cycles of Hg. However, preconcentration is indispensable for the determination of samples with low Hg contents (e.g., ng L−1 levels), which is time-consuming and requires a lot of manpower and materials. Herein, a sensitive method for the online determination of Hg isotopic compositions by automated purge & trap (P&T) coupled with multicollector inductively coupled plasma-mass spectrometry (MC-ICPMS) was developed. Rapid Hg isotopic analysis was realized in 15 min (single sample-standard bracketing procedure) with a sample consumption of 25 mL per measurement. The optimization of the P&T module and MC-ICPMS was conducted to obtain a high sensitivity for Hg isotopic determination (202Hg max intensity over 10 V for 40 ng L−1 Hg solution). Strategic signal acquisition and data treatment using the linear regression slope without time-lag correction were applied. Accurate isotopic compositions in a referenced standard solution at 8 ng L−1 (NIST 3177, δ202Hg −0.55 ± 0.29‰, Δ199Hg −0.02 ± 0.23‰, Δ200Hg 0.01 ± 0.19‰, Δ201Hg −0.02 ± 0.16‰, 2SD, and N = 31) and certified reference materials (CRMs) at 40 ng L−1 were obtained (NRC DORM-4, δ202Hg 0.45 ± 0.14‰, Δ199Hg 1.73 ± 0.16‰, Δ200Hg 0.06 ± 0.08‰, Δ201Hg 1.42 ± 0.13‰, 2SD, N = 13; NIST 1632e, δ202Hg −2.22 ± 0.19‰, Δ199Hg −0.02 ± 0.07‰, Δ200Hg 0.00 ± 0.07‰, Δ201Hg −0.01 ± 0.09‰, 2SD, and N = 20). The measuring concentration of this proposed method has decreased from μg L−1 to ng L−1 levels compared to CV introduction. The sample size and analytical time are 2–3 orders of magnitude lower compared to offline preconcentration methods (several hours to process several to dozens of liters). This proposed method can be used for the analysis of Hg isotopic compositions in solution samples with low Hg concentrations including natural aquatic samples. [ABSTRACT FROM AUTHOR]