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1.
Materials (Basel) ; 17(10)2024 May 08.
Article in English | MEDLINE | ID: mdl-38793264

ABSTRACT

As a key guarantee and cornerstone of building quality, the importance of deformation prediction for deep foundation pits cannot be ignored. However, the deformation data of deep foundation pits have the characteristics of nonlinearity and instability, which will increase the difficulty of deformation prediction. In response to this characteristic and the difficulty of traditional deformation prediction methods to excavate the correlation between data of different time spans, the advantages of variational mode decomposition (VMD) in processing non-stationary series and a gated cycle unit (GRU) in processing complex time series data are considered. A predictive model combining particle swarm optimization (PSO), variational mode decomposition, and a gated cyclic unit is proposed. Firstly, the VMD optimized by the PSO algorithm was used to decompose the original data and obtain the Internet Message Format (IMF). Secondly, the GRU model optimized by PSO was used to predict each IMF. Finally, the predicted value of each component was summed with equal weight to obtain the final predicted value. The case study results show that the average absolute errors of the PSO-GRU prediction model on the original sequence, EMD decomposition, and VMD decomposition data are 0.502 mm, 0.462 mm, and 0.127 mm, respectively. Compared with the prediction mean square errors of the LSTM, GRU, and PSO-LSTM prediction models, the PSO-GRU on the PTB0 data of VMD decomposition decreased by 62.76%, 75.99%, and 53.14%, respectively. The PTB04 data decreased by 70%, 85.17%, and 69.36%, respectively. In addition, compared to the PSO-LSTM model, it decreased by 8.57% in terms of the model time. When the prediction step size increased from three stages to five stages, the mean errors of the four prediction models on the original data, EMD decomposed data, and VMD decomposed data increased by 28.17%, 3.44%, and 14.24%, respectively. The data decomposed by VMD are more conducive to model prediction and can effectively improve the accuracy of model prediction. An increase in the prediction step size will reduce the accuracy of the deformation prediction. The PSO-VMD-GRU model constructed has the advantages of reliable accuracy and a wide application range, and can effectively guide the construction of foundation pit engineering.

2.
Materials (Basel) ; 17(10)2024 May 11.
Article in English | MEDLINE | ID: mdl-38793330

ABSTRACT

In this paper, four water-binder ratios (w/b) of 0.29, 0.33, 0.39, and 0.46 were designed. A variable test temperature was implemented in the drying-wetting cycle test according to the temperature fluctuations in the actual service environment, and the constant temperature test was established as the control group. The mechanical properties and chloride corrosion resistance of concrete with different w/b ratios under variable temperature drying-wetting cycles, as well as the microstructure changes, phase composition, and damage mechanism inside the concrete, were investigated. The results showed that the mechanical properties of concrete increased first and then decreased with drying-wetting cycles increasing, whereas the chloride corrosion resistance continued to decline. A higher w/b exacerbated the deterioration of the concrete performance. A higher w/b increased the porosity, chloride diffusion depth, and chloride content, thus reducing the resistance of chloride corrosion. Compared with w/b = 0.29, the compressive strength, splitting tensile strength, mass, and relative dynamic elasticity modulus of w/b = 0.46 exposed to 60 drying-wetting cycles decreased by 54.50%, 52.44%, 0.96%, and 6.50%, respectively, while the porosity, peak chloride content, and erosion depth increased by 45.12%, 70.45%, and 45.00%. Compared with the drying-wetting cycle with a constant temperature, the cumulative damage caused by the drying-wetting cycle with a variable temperature was greater, resulting in more severe deterioration of concrete performance. The increase in the test temperature significantly accelerated the diffusion rate, penetration depth, and chemical binding capacity of chloride ions. After 60 drying-wetting cycles, the peak chlorine content and erosion depth of w/b = 0.46 under variable temperature cycles were 15.38% and 10.32% higher than those under a constant temperature, while the compressive strength, splitting tensile strength, mass, and relative dynamic elastic modulus were reduced by 7.76%, 14.81%, 0.33%, and 2.40%, respectively. Microscopic analysis confirmed that higher w/b and variable temperature cycles accelerated the decay of mechanical properties and the decline of chloride corrosion resistance. According to the numerical fitting analysis, the w/b should be 0.29~0.39 under the condition that the mechanical properties and chloride corrosion resistance of concrete are met.

3.
Materials (Basel) ; 16(18)2023 Sep 20.
Article in English | MEDLINE | ID: mdl-37763586

ABSTRACT

Nano-SiO2 (NS) is widely used in cement-based materials due to its excellent physical properties. To study the influence of NS content on a cement paste and the interfacial transition zone (ITZ), cement paste samples containing nano content ranging from 0 to 2% (by weight of cement) were prepared, and digital image correlation (DIC) technology was applied to test the mechanical properties. Finally, the optimal NS content was obtained with statistical analysis. The mini-slump cone test showed that, with the help of superplasticizer and ultrasonic treatment, the flowability decreased continuously, as the NS content increased. The DIC experimental results showed that NS could effectively improve the mechanical properties of the cement paste and the ITZ. Specifically, at the content level of 1%, the elastic modulus of cement paste and ITZ was 20.95 GPa and 3.20 GPa, respectively. When compared to that without nanomaterials, the increased amplitude was 73.50% and 90.50%, respectively. However, with the further increase in NS content, the mechanical properties decreased, which was mainly caused by the agglomeration of nanomaterials. Additionally, the NS content did not exhibit a significant effect on the thickness of the ITZ, and its value was maintained at 76.91-91.38 µm. SEM confirmed that NS would enhance the microstructure of both cement paste and ITZ.

4.
J Hazard Mater ; 459: 132280, 2023 10 05.
Article in English | MEDLINE | ID: mdl-37591168

ABSTRACT

Cadmium (Cd) contamination poses serious risks to soil ecosystems and human health. Herein, the effect of two drunken horse grasses (Achnatherum inebrians) including endophytes Epichloë gansuensis infected (E+ ) and uninfected (E-) on the phytoremediation of Cd-contaminated soils were analyzed by coupling high-throughput sequencing and soil metabolomics. The results showed that the high-risk soil Cd decreased and the medium- and low-risk Cd fraction increased to varying degrees after planting E+ and E- plants in the soil. Meanwhile, total Cd content decreased by 19.7 % and 35.1 % in E+ and E- A. inebrians-planted soils, respectively. Principal coordinate analysis revealed a significant impact of E+ and E- plants on the soil microbial community. Most stress-tolerant and gram-positive functional bacterial taxa were enriched to stabilize Cd(II) in E+ planted soil. Several beneficial fungal groups related to saprotroph and symbiotroph were enriched to absorb Cd(II) in E- soil. Soil metabolomic analysis showed that the introduction of A. inebrians could weaken the threat of CdCl2 to soil microbe metabolism and improve soil quality, which in turn promoted plant growth and improved phytoremediation efficiency in Cd-contaminated soil. In conclusion, A. inebrians plants alleviate soil Cd pollution by regulating soil microbial metabolism and microbial community structure. These results provide valuable information for an in-depth understanding of the phytoremediation mechanisms of A. inebrians.


Subject(s)
Cadmium , Microbiota , Humans , Animals , Horses , Biodegradation, Environmental , Cadmium/toxicity , Poaceae , Soil
5.
Materials (Basel) ; 16(3)2023 Feb 03.
Article in English | MEDLINE | ID: mdl-36770311

ABSTRACT

Recycled fine aggregate (RFA) produced from concrete waste is commonly used in the construction industry; however, its use for structural concrete members has not been extensively studied. Moreover, its durability in a drying-wetting cycle environment still needs to be examined. In this study, the intrusion process of chloride in concrete under the drying-wetting cycles is experimentally characterized. Chloride penetration tests are carried out on concrete with the incorporation of different RFA replacement rates and mineral admixtures (i.e., fly ash and silica fume). The results show that the chloride penetration of recycled fine aggregate concrete (RFAC) is dependent upon the performance of the concrete itself, while the deterioration of chloride ion erosion resistance is due to the combined action of the replacement rate of RFA and the drying-wetting cycles. The incorporation of RFA degrades the properties of RFAC owing to its drawbacks in the degradation of interfacial properties of RFAC. Exposure to the drying-wetting cycle environment causes the content of free chloride ions in RFAC to increase initially before decreasing with the erosion depth, thereby showing an obvious convection zone and diffusion zone. The incorporation of the mineral admixture can effectively improve the compactness of the concrete microstructure and make concrete less susceptible to chloride ions ingress. RFAC mixed with 15% fly ash and 10% silica fume has a comparable resistance to chloride penetration as a natural aggregate concrete, which is a feasible method for the application of RFA.

6.
Int J Mol Sci ; 23(21)2022 Oct 28.
Article in English | MEDLINE | ID: mdl-36361880

ABSTRACT

Soil cadmium (Cd) pollution is a serious environmental problem imperiling food safety and human health. The endophyte Epichloë gansuensis can improve the tolerance of Achnatherum inebrians to Cd stress. However, it is still unknown whether and how the endophyte helps host plants build up a specific bacterial community when challenged by CdCl2. In this study, the responses of the structure and function of bacterial community and root exudates of E+ (E. gansuensis infected) and E- (E. gansuensis uninfected) plants to Cd stress were investigated. Analysis of bacterial community structure indicated that the rhizosphere bacterial community predominated over the root endosphere bacterial community in enhancing the resistance of CdCl2 in a host mediated by E. gansuensis. E+ plant strengthened the interspecific cooperation of rhizosphere bacterial species. Moreover, the analysis of root exudates demonstrated E. gansuensis and increased the contents of organic acids and amino acids under Cd stress, and most root exudates were significantly correlated with rhizosphere bacteria. These results suggested that E. gansuensis employed a specific strategy to recruit distinct rhizosphere bacterial species and relevant functions by affecting root exudates to improve the tolerance of the host to Cd stress. This study provides a firm foundation for the potential application of symbionts in improving phytostabilization efficiency.


Subject(s)
Cadmium , Epichloe , Humans , Cadmium/metabolism , Rhizosphere , Poaceae , Endophytes/physiology , Bacteria , Seeds , Exudates and Transudates , Plant Roots/metabolism
7.
Materials (Basel) ; 14(20)2021 Oct 15.
Article in English | MEDLINE | ID: mdl-34683715

ABSTRACT

Deep T-section beams have been widely used in engineering structures due to their high bearing capacity, high construction efficiency and economic benefits, while the current beam design theory can hardly interpret reasonably the mechanical behaviors of deep beams. The performance features of the deep T-beam were investigated, involving in strain distribution and principal stress trace using experimental tests. Different near surface mounted (NSM) reinforcement schemes were proposed for deep T-beams aiming at improving the shear capacity. The results show that the behaviors of deep T-beams dissatisfy the assumption of plane cross-section, and the 'strut-and-tie' model is applicable in such structures. The reinforcement systems can significantly relieve the strain concentration, mid-span deflection and crack width in deep T-beams, consequently improving the shear capacity range from 45 to 65%. The scheme is preferential for the reinforcement of deep T-beams when the applied angles, positions and lengths of CFRP bars are optimized based on the 'strut-and-tie' model.

8.
Drug Des Devel Ther ; 14: 603-611, 2020.
Article in English | MEDLINE | ID: mdl-32103902

ABSTRACT

BACKGROUND: Chronic kidney disease (CKD) has become a major public health issue. Meanwhile, renal fibrosis caused by diabetic nephropathy can lead to CKD, regardless of the initial injury. It has been previously reported that silibinin or valsartan could relieve the severity of renal fibrosis. However, the effect of silibinin in combination with valsartan on renal fibrosis remains unclear. MATERIAL AND METHODS: Proximal tubular cells (HK-2) were treated with TGF-ß1 (5 ng/mL) to mimic in vitro model of fibrosis. The proliferation of HK-2 cells was tested by CCK-8. Epithelial-mesenchymal transition (EMT) and inflammation-related gene and protein expressions in HK-2 cells were measured by qRT-PCR and Western-blot, respectively. ELISA was used to test the level of TNF-αNF-A. Additionally, HFD-induced renal fibrosis mice model was established to investigate the effect of silibinin in combination with valsartan on renal fibrosis in vivo. RESULTS: Silibinin significantly increased the anti-fibrosis effect of valsartan in TGF-ß1-treated HK-2 cells via inhibition of TGF-ß1 signaling pathway. Furthermore, silibinin significantly enhanced the anti-fibrosis effect of valsartan on HFD-induced renal fibrosis in vivo through inactivation of TGF-ß1 signaling pathway. CONCLUSION: These data indicated that silibinin markedly increased anti-fibrosis effect of valsartan in vitro and in vivo. Thus, silibinin in combination with valsartan may act as a potential novel strategy to treat renal fibrosis caused by diabetic nephropathy.


Subject(s)
Diabetic Nephropathies/drug therapy , Kidney Tubules, Proximal/drug effects , Silybin/pharmacology , Transforming Growth Factor beta1/metabolism , Valsartan/pharmacology , Animals , Cell Line , Diabetic Nephropathies/complications , Disease Models, Animal , Drug Synergism , Epithelial-Mesenchymal Transition/drug effects , Fibrosis/prevention & control , Humans , Kidney Tubules, Proximal/metabolism , Male , Mice , Mice, Inbred C57BL , Renal Insufficiency, Chronic/prevention & control , Signal Transduction/drug effects , Silybin/administration & dosage , Valsartan/administration & dosage
9.
Afr Health Sci ; 20(1): 509-514, 2020 Mar.
Article in English | MEDLINE | ID: mdl-33402939

ABSTRACT

INTRODUCTION: The performances of contrast-enhanced ultrasound (CEUS) and digital subtraction angiography (DSA) were used to establish an efficient as well as non-invasive clinical technique for the diagnosis of extra-cranial internal carotid artery (ICA) stenosis. MATERIALS AND METHODS: Thirty-six successive patients (11 women and 25 men, mean age: 65.0 ± 9.2, range: 43-78 years) with internal carotid artery (ICA) stenosis were tested by CEUS and DSA. These tests were carried out by means of Hitachi Preirus ultrasound machine for CEUS and Allura Xper FD20 system (Philips Medical Systems, Nederland B.V.) for DSA. 1.2 ml SonoVue (Bracco, Switzerland) was used a s contrast agent. RESULTS: The results clearly indicated that there were no noteworthy variations among the distributions recorded by CEUS as well as DSA for the four tested groups. The percentage of diameter stenosis calculated by CEUS was clearly in accordance with the DSA images. CEUS showed accurate results with good specificity and sensitivity at 50%, 70%, and 100%. Also, CEUS performance was relatively better than DSA in the diagnosis of ICA and suitability of CEA. CONCLUSION: CEUS proved to be a precise non-invasive testing method for the diagnosis of carotid artery stenosis which is more feasible and well-tolerated in patients with various stages of carotid stenosis.


Subject(s)
Angiography, Digital Subtraction/methods , Carotid Stenosis/diagnostic imaging , Ultrasonography/methods , Adult , Aged , Carotid Stenosis/diagnosis , Contrast Media , Female , Humans , Male , Middle Aged , Predictive Value of Tests , Retrospective Studies , Sensitivity and Specificity , Severity of Illness Index
10.
Biomed Pharmacother ; 118: 109309, 2019 Oct.
Article in English | MEDLINE | ID: mdl-31545237

ABSTRACT

To explore the roles of long noncoding RNA (lncRNA) FOXF1 Adjacent Non-Coding Developmental Regulatory RNA (FENDRR) in human non-small cell lung cancer (NSCLC). The levels of FENDRR in NSCLC cells and tissues were analyzed using qRT-PCR assay. The growth and colony formation abilities of NSCLC cell were analyzed by the MTT and colony formation tests. The mobility and invasiveness of NSCLC cell were analyzed using the wound closure and Transwell invasion assay. The impact of FENDRR on the tumor growth of NSCLC cells in vivo was detected using xenograft model. Bioinformatics analysis and luciferase reporter gene bioassay were selected to identify the bindings sites between miR-761 and FENDRR. Additional, the results of Transwell invasion and colony formation experiments indicated that FENDRR inhibited the aggressiveness of NSCLC depend on miR-761. Tissue inhibitor of metalloproteinase 2 (TIMP2) was identified as the downstream target of miR-761 and its level was positively regulated by FENDRR. Cotransfection assays using A549 and H1975 cells future implied that downexpression of TIMP2 rescued the aggressiveness phenotypes of NSCLC cell inhibited by FENDRR. Altogether, we demonstrated that lncRNA FENDRR suppressed the progression of NSCLC via binding to miR-761 and regulating TIMP2 expression.


Subject(s)
Carcinoma, Non-Small-Cell Lung/genetics , Disease Progression , Gene Expression Regulation, Neoplastic , Lung Neoplasms/genetics , MicroRNAs/genetics , RNA, Long Noncoding/metabolism , Tissue Inhibitor of Metalloproteinase-2/genetics , Base Sequence , Carcinoma, Non-Small-Cell Lung/pathology , Cell Line, Tumor , Cell Movement/genetics , Cell Proliferation/genetics , Down-Regulation/genetics , Humans , Lung Neoplasms/pathology , MicroRNAs/metabolism , Neoplasm Invasiveness , Phenotype , RNA, Long Noncoding/genetics , Tissue Inhibitor of Metalloproteinase-2/metabolism , Tumor Stem Cell Assay
11.
Ultrasound Med Biol ; 40(7): 1394-9, 2014 Jul.
Article in English | MEDLINE | ID: mdl-24642221

ABSTRACT

The goal of the work described here was to evaluate the role of virtual touch tissue quantification (VTQ) combined with urinary ß2-microglobulin (ß2-MG) measurement in the early diagnosis of gouty kidney damage. Two hundred fifty-nine patients with gouty kidney damage and 200 healthy control subjects were tested. The shear wave velocity (SWV) of the renal parenchyma and sinus as determined with VTQ and the urinary ß2-MG level of the two groups were analyzed. Although there were no significant differences in age, body mass index, creatinine level and blood urea nitrogen between the two groups (all p's > 0.05), the aforementioned parameters were higher in the group with gouty kidney damage than in the control group. Urinary ß2-MG levels of the patients with kidney damage were significantly higher than those of the control subjects (t = 6.38, p < 0.01). The SWV of the renal parenchyma was higher than that of the sinus in both groups. Compared with controls, patients with kidney damage had significantly increased renal parenchyma and sinus SWVs (all p-values < 0.05). Urinary ß2-MG level was positively linearly correlated with the SWV of renal parenchyma in patients with kidney damage (r = 0.442, p < 0.0001). However, there was no correlation between urinary ß2-MG level and the SWV of the sinus in patients with kidney damage (r = 0). In the control group, there was no correlation between urinary ß2-MG level and the SWV of the renal parenchyma or sinus. The elasticity of the kidney as determined with VTQ, combined with the urinary ß2-MG level, may be helpful in the early diagnosis of gouty kidney damage.


Subject(s)
Elasticity Imaging Techniques/methods , Gout/complications , Gout/diagnosis , Image Interpretation, Computer-Assisted/methods , Kidney Diseases/diagnosis , Kidney Diseases/etiology , beta 2-Microglobulin/urine , Adolescent , Adult , Aged , Algorithms , Biomarkers/urine , Female , Gout/blood , Gout/urine , Humans , Kidney Diseases/blood , Kidney Diseases/urine , Male , Middle Aged , Palpation , Pilot Projects , Reproducibility of Results , Sensitivity and Specificity , Touch , User-Computer Interface , Young Adult
12.
J Autom Methods Manag Chem ; 24(4): 121-5, 2002.
Article in English | MEDLINE | ID: mdl-18924732

ABSTRACT

The paper describes an energy-dispersive X-ray spectrometer for a scanning electron microscope (SEM-EDXS). It was constructed using the new architecture of a virtual instrument (VI), which is low-cost, space-saving, fast and flexible way to develop the instrument. Computer-aided teaching (CAT) was used to develop the instrument and operation rather than a traditional instrument technique. The VI was designed using the object-oriented program language C++ and compact programmable logical devices (CPLD). These include spectra collection and processing, quantitative analysis and X-ray-intensity distribution analysis. The procedure is described in detail. The VI system gives an e inverted exclamation markective and user-friendly human interface for the whole analytical task. Some examples are described.

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