In this paper, in order to reduce the time cost of prediction experiments in industry, a new narrow gap oscillation calculation method is developed in ABAQUS thermomechanical coupling analysis to ...study the distribution trend of residual weld stresses in comparison with conventional multi-layer welding processes. The blind hole detection technique and thermocouple measurement method verify the reliability of the prediction experiment. The results show that the experimental and simulation results have a high degree of agreement. In the prediction experiments, the calculation time of the high-energy single-layer welding experiments is 1/4 of the traditional multi-layer welding. Two welding processes of longitudinal residual stress and transverse residual stress distribution trends are the same. The high-energy single-layer welding experiment stress distribution range and transverse residual stress peak are smaller, but the longitudinal residual stress peak is slightly higher, which can be effectively reduced by increasing the preheating temperature of the welded parts. This implies that in the specific case of increasing the initial temperature of the workpiece, the use of high-energy single-layer welding instead of multi-layer welding to study the residual stress distribution trend not only optimizes the weld quality but also reduces the time cost to a large extent.
The objective of this study was to examine the impact of corona discharge plasma (CDP) treatments of different durations (1, 3, 5, and 10 min) on the drying kinetics and quality attributes of lilies, ...including color, enzyme activities, total phenols content (TPC), and antioxidant activity. The microstructure of lilies under different CDP conditions were also investigated. As a result, all CDP treatments enhanced the drying rate relative to untreated lilies, and the shortest drying time of 7 h was obtained at CDP-3 minute samples. CDP treatment led to a higher retention in the TPC of dried lilies. Microstructural analysis revealed the formation of irregular micropores on the surface of the lilies after CDP treatment, which was closely associated with the accelerated drying rate and improved bioactive substances of the dried product. In conclusion, CDP has emerged as a novel and beneficial pretreatment technique that accelerates the drying process and enhances the nutritional qualities of dried lilies.
•Corona discharge plasma application was tested as a pretreatment to drying of lilies.•CDP pretreatment markedly enhanced the drying ratio and rehydration ratio.•The CDP treatment did not demonstrate a competitive advantage in terms of preserving color.•The use of CDP increased the preservation of TPC, TFC and antioxidant activity in dried lilies.
The welding process has been an efficient method for producing essential and complex manufacturing parts in various industrial design fields. The post-weld residual stress can have detrimental ...effects on welded components. Therefore, systematic studies of residual stress are essential for evaluating welding behaviors and mechanisms in welded structures. They can provide a valuable reference and optimization for addressing residual stress relief. Numerical finite element analyses based on thermal-mechanical models offer a comprehensive approach to simulate real welding, providing a reliable means to determine and quantify the distribution of residual stress based on welding parameters and material properties. Furthermore, the finite element analysis is capable of generating adequate and dependable datasets in relation to the classical experiment. However, the finite element simulation is not considered an efficient method for predicting the magnitude and distortion of residual stress due to its high computational cost. A deep learning framework with powerful automatic learning abilities could potentially be used as an alternative method to efficiently predict residual stress. The purpose of the current study is to propose an innovative modeling approach for accurately and effectively predicting residual stress. A deep network model with Convolutional Neural Network using Adam optimization is integrated with numerical finite element analyses of a single-pass beam weld in SUS304 stainless steel. Finite element analysis is used to generate extensive residual stress datasets, which are partly used to train the deep network model and partly used for model validation. The deep network model aligns closely with the finite element analysis results, with a root-mean-square error (RMSE) of less than 12, an absolute fraction of variation (R2) of greater than 0.95, a mean absolute error (MAE) of less than 6.8 and a mean absolute percentage error (MAPE) of less than 1.1. Furthermore, this study highlights the potential advantage of using a deep network model with strong memory capabilities to directly predict residual stress for identical structural components and welding processes.
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Implementation of the Grain for Green program (GGP) resulted in great changes in land use and cover in northwest China, and presumably in the region's carbon. However, accurate assessment of the ...effects of the GGP on carbon storage remains a challenge. The Integrated Valuation of Ecosystem Services and Tradeoffs (InVEST) model can map and evaluate natural goods and services that sustain life and quantify their impact from the changes in the ecosystem. Taking Huining County in China's Loess Plateau region as a case, the land use and land cover changes (LUCC) following the GGP were quantified, and their effects on carbon storage between 2000 and 2016 were evaluated using the InVEST model. The results showed that, a total area of about 3996.13 km2 underwent changes following the GGP in Huining County during the study period, accounting roughly for 74% of the county. The total carbon storage increased from 6470.72 Gg in 2000 to 7335.07 Gg in 2016. Spatially, carbon density in the south of this county was greater than the northern part. Directly induced by the GGP (conversions of farmlands to forests and grasslands), the carbon storage increased by 786.84 Gg in total, with a rate of 46.28 Gg per year, the majority of which occurred during the first stage of the study period (from 2000 to 2008). The increase of carbon storage was mostly attributable to the increases in vegetation pool and the carbon density showed a strong spatial correlation with the growing season Normalized Difference Vegetation Index (NDVI). The similarities between carbon density and NDVI spatial patterns during the study period may have been shaped by the county's climate patterns, but not to any significant extent by climate change during the study period. This county-scale study allows for a deeper understanding of the links between LUCC induced by environmental restoration programs and carbon storage changes, and contributes to a greater accuracy in the estimation of carbon storage at the provincial (or larger) scale.
•Land use changed significantly with implementation of the Grain for Green Program in Huining County.•Carbon storage greatly increased with land use change, from 6470 Gg in 2000–7335 Gg in 2016.•Vegetation pools played a major role in increases of carbon storage.•Preventing conversions of forests and grassland to farmlands can improve the carbon sequestration effects of the GGP.•This study can contribute to the accurate estimation of carbon storage at a provincial or wider scale.
In order to understand the mechanism of the difference of Cd absorption and Cd enrichment in different ryegrass varieties, pot experiment was conducted to study on the response of two varieties of ...ryegrass (Bond and Abbott) to Cd stress as well as the differences of Cd uptake and expression of
MT
family genes and
NRAMP2
. Results showed that root dry weights of two varieties and shoot dry weights of Abbott increased first and then decreased with the increase of Cd level in soil. When exposed to 75 mg kg
−1
Cd, shoot dry weight and plant dry weight of Abbott both reached maximum values (10.92 and 12.03 g pot
−1
), which increased by 11.09 and 10.67% compared with the control, respectively. Shoot dry weight and plant dry weight of Bond decreased with the increase of Cd level in soil. When the Cd level in soil was 75 mg kg
−1
, shoot Cd concentrations of the two varieties were 111.19 mg kg
−1
(Bond) and 133.69 mg kg
−1
(Abbott), respectively, both of which exceeded the critical value of Cd hyperaccumulator (100 mg kg
−1
). The expression of
MT
gene family and
NRAMP2
in the leaf of Bond variety significantly increased at the Cd level of 75 mg kg
−1
and reached maximum value (except
MT2C
) at Cd level of 150 mg kg
−1
. The expression of
MT
gene family in the stem of Bond variety showed a double-peak pattern, while the expression of
NRAMP2
was a single-peak pattern. The expression of
MT
gene family and
NRAMP2
in Abbott variety was consistent with single-peak pattern. The expression of
MT
gene family and
NRAMP2
in leaf both significantly increased at Cd level of 150 mg kg
−1
, while that in stem and root significantly increased at Cd level of 75 mg kg
−1
. For both varieties of ryegrass, the expression amount of
MT
family genes and
Nramp2
in leaf was higher than that in root and stem, indicating the Cd tolerance of ryegrass can be improved by increasing the expression levels of
MT
family genes and
Nramp2
in stem and root. There was significant genotypic difference in the expression of
MT
gene family and
NRAMP2
between the two varieties of ryegrass, and the expression of
MT
gene family and
NRAMP2
in leaves and stems of Bond variety was higher than that in Abbott variety, while the expression of
MT
gene family and
NRAMP2
in roots of Abbott variety was higher than that in Bond variety. The two gene families investigated in this study may be closely related to Cd uptake, but not related to Cd transport from root to leaf and Cd enrichment in shoot.
Pot experiments were conducted to study the effects of different cadmium (Cd) levels (0, 75, 150, 300 and 600 mg kg
−1
) on the growth, cadmium concentration and cadmium accumulation of two varieties ...of ryegrass, and the correlation between plant cadmium concentration and soil cadmium chemical forms. The results showed that root dry weight of the two varieties of ryegrass, dry weight of shoot and plant in Aubade increased first and then decreased with the increase of soil cadmium. When the soil cadmium level was 75 mg kg
−1
, shoot dry weight and plant dry weight in Aubade reached the maximum (10.92 g pot
−1
and 12.03 g pot
−1
), which was 11.13% and 10.67% higher than that of the control respectively. The cadmium form in shoot of the two ryegrass varieties was dominated by was sodium chloride extraction (F-NaCl), followed by deionized water extracted (F-W) and acetic acid extracted (F-HAC). The cadmium forms in soils were mainly exchangeable (EXC-Cd), and cadmium concentrations of leaf, stem and root were significantly positively correlated with exchangeable cadmium content in the rhizosphere soil (
P
< 0.01). The EXC-Cd content in Abbott soil was higher than that in Bond, which was consistent with Abbott’s Cd absorption above Bond. The cadmium transport factor of the two ryegrass varieties were less than 1, and cadmium bioconcentration factor were all greater than 1. In comparison of the two ryegrass varieties, the dry weight of shoot and plant of Abbott were higher than that of Bond under the stress of 75–600 mg kg
−1
Cd. The cadmium concentration and cadmium accumulation of shoot and root in Abbott were also higher than that of Bond. There was a genotypic difference in ryegrass tolerance to cadmium and cadmium absorption. Abbott was more suitable as a phytoremediation material for soil cadmium pollution.
Pot experiment was conducted to study the difference of cadmium uptake and
OAS
and
IRT
genes’ expression between the two ryegrass varieties under cadmium stress. The results showed that with the ...increase of cadmium levels, the dry weights of roots of the two ryegrass varieties, and the dry weights of shoots and plants of Abbott first increased and then decreased. When exposed to 75 mg kg
−1
Cd, the dry weights of shoot and plant of Abbott reached the maximum, which increased by 11.13 and 10.67% compared with the control. At 75 mg kg
−1
Cd, cadmium concentrations in shoot of the two ryegrass varieties were higher than the critical value of Cd hyperaccumulator (100 mg kg
−1
), 111.19 mg kg
−1
(Bond), and 133.69 mg kg
−1
(Abbott), respectively. The
OAS
gene expression in the leaves of the two ryegrass varieties showed a unimodal curve, which was up to the highest at the cadmium level of 150 mg kg
−1
, but fell back at high cadmium levels of 300 and 600 mg kg
−1
. The
OAS
gene expression in Bond and Abbott roots showed a bimodal curve. The
OAS
gene expression in Bond root and Abbott stem mainly showed a unimodal curve. The expression of
IRT
genes family in the leaves of ryegrass varieties was basically in line with the characteristics of unimodal curve, which was up to the highest at cadmium level of 75 or 150 mg kg
−1
, respectively. The
IRT
expression in the ryegrass stems showed characteristics of bimodal and unimodal curves, while that in the roots was mainly unimodal. The expression of
OAS
and
IRT
genes was higher in Bond than that in Abbott due to genotype difference between the two varieties. The expression of
OAS
and
IRT
was greater in leaves than that in roots and stems. Ryegrass tolerance to cadmium can be increased by increasing the expression of
OAS
and
IRT
genes in roots and stems, and transfer of cadmium from roots and stems to the leaves can be enhanced by increasing expression
OAS
and
IRT
in leaves.
AIM: Despite the presence of lymphocyte infiltration, human hepatocellular carcinoma (HCC) is typically a rapidly progressive disease. The mechanism of regulation of lymphocyte migration is poorly ...understood. In this study, we investigated various factors regulating T cell migration in HCC patients. We examined serum CXC chemokine levels in HCC patients and demonstrated the production of CXC chemokines by HCC cell lines. We determined the effect of both HCC patient serum and tumor cell conditioned supernatant upon lymphocyte expression of chemokine receptor CXCR3 as well as lymphocyte migration. Lastly, we examined the chemotactic responses of lymphocytes derived from HCC patients. METHODS: The serum chemokines IP-10 (CXCL10) and Mig (CXCL9) levels were measured by cytometric bead array (CBA) and the tumor tissue IP-10 concentration was measured by ELISA. The surface expression of CXCR3 on lymphocytes was determined by flow cytometry. The migratory function of lymphocytes to the corresponding chemokines was assessed using an in vitro chemotactic assay. Phosphorylation of extracellular signal-regulated kinase (ERK) was determined by Western blot analysis. RESULTS: Increased levels of IP-10 and Mig were detected in HCC patient serum and culture supernatants of HCC cell lines. The IP-10 concentration in the tumor was significantly higher than that in the non-involved adjacent liver tissues. HCC cell lines secreted functional chemokines that induced a CXCR3-specific chemotactic response of lymphocytes. Furthermore, tumor-cell-derived chemokines induced initial rapid phosphorylation of lymphocyte ERK followed by later inhibition of ERK phosphorylation. The culture of normal lymphocytes with HCC cell line supernatants or medium containing serum from HCC patients resulted in a significant reduction in the proportion of lymphocytes exhibiting surface expression of CXCR3. The reduction in T cell expression of CXCR3 resulted in reduced migration toward the ligand IP-10, and both CD4^+ and CD8^+ T cells from HCC patients exhibited diminished chemotactic responses to IP-10 in vitrocompared to T cells from healthy control subjects. CONCLUSION: This study demonstrates functional desensitization of the chemokine receptor CXCR3 in lymphocytes from HCC patients by CXCR3 ligands secreted by tumor cells. This may cause lymphocyte dysfunction andsub sequently impaired immune defense against the tumor.
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