Effects of temperature variations on the deflections of airfield jointed plain concrete pavements

This paper aims to study the influences of temperature variations on airfield jointed plain concrete pavement (JPCP) deflections. The maximum deflection at the transverse joint (D0j), the maximum deflection at the corner of a slab (D0c), and the deflection basin at the centre of a slab were considered. The in-situ deflection measurements at three civil airports were conducted over a 24-hour period and numerical simulations for JPCP at a civil airport were performed as well. The results indicate that the temperature change slightly affects the deflection basin at the centre of a slab unless the positive temperature gradient in the slab increases to exceed a certain critical value. But both D0j and D0c are significantly affected by temperature variations. The results of in-situ tests show that D0j (or D0c) is almost stable from 1 pm and 5 pm in a day. At other times of one day, there is a strong negative liner correlation between D0j (or D0c) and the pavement surface temperature during the heating period and the cooling period, respectively. The results of numerical simulations reveal that both D0j and D0c gradually increase with the increase of the average temperature. The results of numerical simulations also suggest that a critical negative/positive temperature gradient exists at the transverse joint while there is a critical positive temperature gradient at the slab corner. Besides, all the critical temperature gradients are seldom affected by the average temperature. When the temperature gradient exceeds the critical value, D0j, D0c and all values of the deflection basin have a strong positive linear correlation with the temperature gradient. Keywords: Jointed plain concrete pavement, Falling weight deflectometer, Numerical simulations, Temperature variations, Deflection

Structural optimization and performance evaluation of precast concrete pavement with composite base layer

This paper proposed a precast concrete pavement structure with the composite base layer comprised of the concrete beam and the filling low strength materials (B-PCP). The mechanical responses of the B-PCP induced by moving wheel loads coupled with temperature loads were analysed using the finite element method. Then the optimal geometry of the concrete beam was determined based on the sensitivity analysis, considering the tensile stress of both the slab and the beam of the base layer, the slab curling, and the faulting. Furthermore, the performance evaluation of the B-PCP was conducted by the numerical analysis and the scale experiment testing, respectively. The results showed that the optical concrete beam was 0.8 ∼ 1.0 m wide and 0.2 ∼ 0.3 m thick. The numerical results showed that the optimal B-PCP structure had a good fatigue resistance performance, and the corresponding slab curling decreased by almost 40% compared with that of the traditional precast concrete pavement. Meanwhile, the scale experiment testing verified that the optimal B-PCP structure exhibited an excellent ability to resist the deformation. The results also showed that the bearing capacity of the optimal B-PCP structure was larger than 350kN, indicating a good bearing capacity

Identification of Moving Load Characteristic on Pavement Using F-P Cavity Fiber Optical Technology

The weigh-in-motion (WIM) system is a necessary piece of equipment for an intelligent road. It can provide real-time vehicle weight and lateral distribution data on wheel load to effectively support pavement structure design and service life analysis for autonomous driving. This paper proposed an enhanced weigh-in-motion sensors system using Fabry–Pérot (F-P) cavity fiber optical technology. Laboratory testing was performed to evaluate the feasibility of the proposed system and field application was conducted as well. The laboratory results show that the traffic loads could be obtained by measuring the center wavelength changes in the embedded F-P Cavity tunable filter. The laboratory results also show that the vehicle load and the number of vehicle axles can be estimated based on the system transfer function between the dynamic loading and the wavelength variation. The field application indicates that the weighting accuracy of the proposed system could reach 94.46% for moving vehicles, and the vehicle passing speed is the potentially relevant factor. The proposed system also has the ability to estimate the number of vehicle axles and the loading position, and the precision could reach 97.1% and 300 mm, respectively

Proteomic study provides new clues for complications of hemodialysis caused by dialysis membrane

The complications of hemodialysis accompanied the hemodialysis and threaten the patients' life. Besides the loss of nutrient substance, such as amino acid and vitamin, we found new clues that the adsorbed proteins on common-used polysulfone-based dialysis membrane might be the reason according to the qualitative proteomic study by ionic liquid assisted sample preparation method. Our results indicated that the adsorbed proteins on the membrane were related with complement activation, blood coagulation, and leukocyte-related biological process. The quantitative proteome further demonstrated some significant changes of signal proteins in the post-dialysis plasma after the hemodialysis, such as beta-2-microglobulin and platelet factor-4, which would further verify these new clues. (C) 2017 Science China Press. Published by Elsevier B.V. and Science China Press. All rights reserved

Surface sieving coordinated IMAC material for purification of His-tagged proteins

Tailor-made materials for the purification of proteins with His-tag was designed through synergizing the selectivity of surface sieving and metal ion affinity. By excluding impurity proteins out of the surface polymer network, such materials could purify His-tagged proteins from the crude cell lysis with purity up to 90%, improved by 14% compared to that obtained by the commercial metal chelating affinity materials. This study might promote the His-tagged protein purification to a new level. (c) 2017 Elsevier B.V. All rights reserved

Genetic Diversity Assessment of Sweetpotato Germplasm in China Using InDel Markers

Sweetpotato (Ipomoea batatas (L.) Lam.), whose roots are rich in starch, is widely grown around the world and plays a prominent role in ensuring food security. At present, there are no reports on the genetic diversity of sweetpotato germplasm revealed by InDel markers. In this study, we developed a set of 30 InDel markers to evaluate the genetic diversity and relationships of 240 accessions, comprising 77 landraces, 80 introduced accessions, 82 improved varieties released in China, and a diploid wild relative Ipomoea trifida. A total of 94 reliable loci were obtained, with a mean of 3.13 loci per primer, and the PIC value ranged from 0.143 to 0.821. The whole population could be divided into three sub-populations according to a structure analysis based on the Bayesian model, which was consistent with the results of principal component analysis (PCA). A neighbor-joining tree was constructed based on Nei’s genetic distance ranging from 0 to 0.556 and discriminated the panel of the population into three main groups (Ⅰ, Ⅱ, Ⅲ). Group Ⅲ was further split into seven subgroups (ⅢA–ⅢG). The clustering pattern of the 240 accessions was unrelated to their geographic origins. Most of the accessions, whether landraces, improved varieties released in China or introduced germplasm, were mixed, which revealed the high level of genetic similarity among accessions from different regions. There was little difference in the level of genetic diversity between landraces and improved varieties, which was probably due to the exchange and utilization of accessions from different regions. More efforts should be made to collect and utilize sweetpotato germplasm resources and further broaden the genetic basis of sweetpotato cultivars

Aptamer-immobilized open tubular capillary column to capture circulating tumor cells for proteome analysis

Circulating tumor cells hold the key to predicting the prognosis and discovering the therapeutic targets. Herein, we proposed a strategy to develop an aptamer-immobilized open tubular capillary column by which SMMC-7721 human hepatoma cells (SMMC-7721 cells) could be captured with an over 70% of capture efficiency and a 3.0 +/- 0.2 of enrichment factor. Owing to the compatibility of the column, the captured cells by the column could be analyzed by LC-MS from protein level and 5 unique proteins of SMMC-7721 cells were identified which could be used as markers to identify SMMC-7721 cells when Jurkat T-leukemia cells (Jurkat cells) were employed as interfering cells. As the key component, the aptamer-immobilized column had the potential to be integrated into the platform for separating, enriching and characterizing rare cells simultaneously

Table_2_Isolation, characterization, and functional verification of salt stress response genes of NAC transcription factors in Ipomoea pes-caprae.xlsx

Adverse environmental stress is a major environmental factor threatening food security, which is why improving plant stress resistance is essential for agricultural productivity and environmental sustainability. The NAC (NAM, ATAF, and CUC) transcription factors (TFs) play a dominant role in plant responses to abiotic and biotic stresses, but they have been poorly studied in Ipomoea pes-caprae. In this research, 12 NAC TFs, named IpNAC1–IpNAC12, were selected from transcriptome data. The homologous evolution tree divided IpNACs into four major categories, and six IpNACs were linearly associated with Arabidopsis ANAC genes. From the gene structures, protein domains, and promoter upstream regulatory elements, IpNACs were shown to contain complete NAC-specific subdomains (A–E) and cis-acting elements corresponding to different stress stimuli. We measured the expression levels of the 12 IpNACs under abiotic stress (salt, heat, and drought) and hormone treatment (abscisic acid, methyl jasmonate, and salicylic acid), and their transcription levels differed. IpNAC5/8/10/12 were located in the nucleus through subcellular localization, and the overexpressing transgenic Arabidopsis plants showed high tolerance to salt stress. The cellular Na+ homeostasis content in the mature and elongation zones of the four IpNAC transgenic sweetpotato roots showed an obvious efflux phenomenon. These conclusions demonstrate that IpNAC5/8/10/12 actively respond to abiotic stress, have significant roles in improving plant salt tolerance, and are important salt tolerance candidate genes in I. pes-caprae and sweetpotato. This study laid the foundation for further studies on the function of IpNACs in response to abiotic stress. It provides options for improving the stress resistance of sweetpotato using gene introgression from I. pes-caprae.</p

Image_1_Isolation, characterization, and functional verification of salt stress response genes of NAC transcription factors in Ipomoea pes-caprae.tif

Adverse environmental stress is a major environmental factor threatening food security, which is why improving plant stress resistance is essential for agricultural productivity and environmental sustainability. The NAC (NAM, ATAF, and CUC) transcription factors (TFs) play a dominant role in plant responses to abiotic and biotic stresses, but they have been poorly studied in Ipomoea pes-caprae. In this research, 12 NAC TFs, named IpNAC1–IpNAC12, were selected from transcriptome data. The homologous evolution tree divided IpNACs into four major categories, and six IpNACs were linearly associated with Arabidopsis ANAC genes. From the gene structures, protein domains, and promoter upstream regulatory elements, IpNACs were shown to contain complete NAC-specific subdomains (A–E) and cis-acting elements corresponding to different stress stimuli. We measured the expression levels of the 12 IpNACs under abiotic stress (salt, heat, and drought) and hormone treatment (abscisic acid, methyl jasmonate, and salicylic acid), and their transcription levels differed. IpNAC5/8/10/12 were located in the nucleus through subcellular localization, and the overexpressing transgenic Arabidopsis plants showed high tolerance to salt stress. The cellular Na+ homeostasis content in the mature and elongation zones of the four IpNAC transgenic sweetpotato roots showed an obvious efflux phenomenon. These conclusions demonstrate that IpNAC5/8/10/12 actively respond to abiotic stress, have significant roles in improving plant salt tolerance, and are important salt tolerance candidate genes in I. pes-caprae and sweetpotato. This study laid the foundation for further studies on the function of IpNACs in response to abiotic stress. It provides options for improving the stress resistance of sweetpotato using gene introgression from I. pes-caprae.</p