In plants, the calmodulin (CaM) proteins is an important calcium-binding protein, which play a crucial role in both regulating plant growth and development, as well as in the resistance mechanisms to ...various biotic and abiotic stresses. However, there is limited knowledge available on the CaM family functions in Solanum pennellii, a wild tomato species utilized as a genetic resource for cultivated tomatoes. In this study, 6 CaM (SpCaM) and 45 CaM-like (SpCML) genes from Solanum pennellii were selected for bioinformatics analysis to obtain insights into their phylogenetic relationships, gene structures, conserved motifs, chromosomal locations, and promoters. The results showed that the 6 SpCaM proteins contained 4 EF-hand domains each, and the 45 SpCML proteins had 2-4 EF-hand domains. The 51 CaM and CaM-like genes contained different intron/exon patterns and they were unevenly distributed across the 12 chromosomes of S. pennellii. The results of the analysis of the conserved motifs and promoter cis-regulatory elements also indicated that these proteins were involved in the responses to biotic and abiotic stresses. qRT-PCR analysis indicated that the SpCaM and SpCML genes had broad expression patterns in abiotic stress conditions and with hormone treatments, in different tissues. The findings of this study will be important for further investigations of the calcium signal transduction mechanisms under stress conditions and lay a theoretical foundation for further exploration of the molecular mechanisms of plant resistance.
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•The API was used to quantify the HDE to the concrete by steam-curing.•Step-curing can remission the HDE of steam-cured concrete.•Adequate subsequent curing will have a positive ...impact on long-term compressive strength and API.
Steam curing is a common method of producing prefabricated elements, achieving high early strength to meet economic benefits. However, this rapid curing method is extremely detrimental to the microstructure and long-term performance of concrete. Therefore, choosing an appropriate measure to remission this adverse effect is critical to the development of long-term performances of steam-cured concrete. In this study, two steam-curing regime and four subsequent curing conditions were employed on the curing of concrete. The long-term compressive strength, surface permeability and microstructure were measured to analyze the effects of curing condition on performance of steam-cured concrete. The results indicate that step-curing is beneficial to the formation of pre-structures, thereby improving the long-term mechanical properties and impermeability of steam-cured concrete. Among the four subsequent curing conditions, saturated limestone immersion is most beneficial to the long-term performance of steam-cured concrete, while water immersion is the most unfavorable.
Abstract
Most
Mycobacterium tuberculosis
(
Mtb
) resistant to rifampicin (RIF) has mutations in the
rpoB
gene, while most
Mtb
resistant to isoniazid (INH) has mutations in the
katG
gene or
inhA
...promoter. We used gene chip technology to detect mutations in these genes to determine the resistance of
Mtb
to RIF and INH. A total of 4148 clinical specimens with sputum smear positivity for acid-fast bacilli (AFB) were detected. Then, taking the results of the drug sensitivity test (DST) as the reference standard, the detection efficiency of sputum samples from different grades of positive smears was compared in detail. We found that the sensitivity of the gene chip method for detecting sputum samples with a grade ≥ AFB 2 + was higher than that of sputum samples with a grade ≤ AFB 1 + (P < 0.05). When the grade of the sample was ≤ AFB 1 +, the sensitivity of the gene chip method was 72.6% for RIF, 67.3% for INH, and 60.0% for MDR-TB. When the grade of the sample was ≥ AFB 2 +, the sensitivity of the gene chip method was 84.5% for RIF, 78.2% for INH, and 73.9% for MDR-TB. The results show that gene chip technology can be directly used to diagnose drug-resistant tuberculosis in clinical specimens, and the diagnostic efficiency for the detection of sputum specimens with a grade ≥ AFB 2 + is better than that of other sputum specimens.
Drought stress can limit the growth and development of tomato seedlings and cause considerable loss of tomato yield. Exogenous abscisic acid (ABA) and calcium (Ca
) can effectively alleviate the ...damage of drought stress to plants in part because Ca
acts as a second messenger in the drought resistance pathway. Although cyclic nucleotide-gated ion channels (CNGCs) are common non-specific Ca
osmotic channels in cell membranes, a thorough understanding of the transcriptome characteristics of tomato treated with exogenous ABA and Ca
under drought stress is necessary to characterize the molecular mechanism of CNGC involved in tomato drought resistance.
There were 12,896 differentially expressed genes in tomato under drought stress, as well as 11,406 and 12,502 differentially expressed genes after exogenous ABA and Ca
application, respectively. According to functional annotations and reports, the 19 SlCNGC genes related to Ca
transport were initially screened, with 11 SlCNGC genes that were upregulated under drought stress and downregulated after exogenous ABA application. After exogenous Ca
application, the data showed that two of these genes were upregulated, while nine genes were downregulated. Based on these expression patterns, we predicted the role of SlCNGC genes in the drought resistance pathway and their regulation by exogenous ABA and Ca
in tomato.
The results of this study provide foundational data for further study of the function of SlCNGC genes and a more comprehensive understanding of drought resistance mechanisms in tomato.
•The subsequent curing regimes has great influence on the mechanical properties and permeability of steam-cured concrete.•Surface permeability can be used to characterize the long-term performance of ...steam-cured concrete.•Adequate subsequent curing will have a positive impact on macro-performance and microstructure of steam-cured concrete.
The accelerated hardening of concrete caused by steam curing has adverse effects on the microstructure and properties of concrete, so it is necessary to adopt appropriate curing method to reduce the damage caused by steam curing. The effects of curing methods on the properties of concrete after steam curing are worth studying. The compressive strength, non-evaporable water content and permeability (air, water and ion) of steam-cured concrete were tested under different subsequent curing conditions. Meanwhile, the internal microstructure was also investigated by image processing and SEM. The results show that the compressive strength of steam-cured concrete with four curing methods increases with the curing time, but the growth rates are different. The permeability of the concretes cured in the air decreased first and then increased with the curing time, while other curing methods decreased with curing time. The microstructure also shows that adequate subsequent wet curing can effectively reduce the adverse effects of steam curing on concrete.
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•The temperature and humidity gradient during steam curing process is closely related to its long-term performance.•Surface covering can significantly reduce surface porosity and ...damage of steam-cured concrete.•The effects of steam-curing regime and surface covering method on the permeability of concrete were evaluated.•The high temperature-humidity gradient during steam curing is detrimental to the development of concrete microstructure.
Steam curing has an adverse effect on the long-term performance of concrete, which is inseparable from the early hygro-thermal coupling action. The temperature-humidity field and performance of steam-cured concrete with different surface covering methods were characterized under the treatment temperature ranging from 45 to 75 ℃ by water permeability along with hydration characteristics, porosity, microhardness, and microstructure. The results show that steam-curing regimes directly affect the long-term performance of steam-cured concrete by changing internal temperature-humidity field. During the steam curing process, a higher treatment temperature often corresponds to a more complex temperature-humidity gradient, so that the steam-cured concrete exhibits low compactness and high permeability. In addition, the surface covering methods can reduce the surface porosity and interface transition zone width of steam-cured concrete. Meanwhile, with the increase of treatment temperature, the improvement effect of the surface covering methods on the impermeability of steam-cured concrete is more obvious.
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Using social network analysis, we compute a firm's network position characteristics and then examine their effects on firm investment efficiency. The results show that both supply ...network centrality and structural holes have no significant impact on corporate overinvestment but can ease corporate underinvestment by alleviating financial constraints. The specific paths are as follows: a firm that has a high level of centrality or rich structural holes in the supply network is more likely to obtain commercial credit and bank loans; however, supply network position has no significant impact on equity financing.
High-strength engineered cementitious composites (ECC) typically require higher cement content, which is negative from the sustainability point of view. To alleviate this problem, herein a low-cost ...and eco-friendly high-strength ECC (with a compressive strength of over 100 MPa) was developed, and diatomite was used to replace a small amount of cement. An appropriate amount of diatomite was found to improve the compressive strength, tensile strength and first cracking strength of ECC, but at the expense of part of the strain capacity (still all higher than 2.9%). Furthermore, the high pozzolanic activity and specific surface area of diatomite also increased the autogenous shrinkage, but reduced the drying shrinkage of ECC due to its internal curing effect. The incorporation of diatomite improved the pore structure of ECC, consumed more Ca(OH)
2,
and enhanced the hydration degree of the mixture. In the end, the economic and environmental benefits of diatomite-modified ECC were also evaluated, and the cost, non-renewable energy demand, and global warming potential of ECC with 3% diatomite were reduced compared to plain ECC by 12.9, 15.1, and 13.3%, respectively. The developed high-strength ECC is therefore a low-cost and eco-friendly alternative to the traditional one.
Gypsum modification is an effective strategy to improve the water resistance of magnesium oxychloride cement paste (MOCP), but its early-ages performance evolution has not received much attention. ...The exothermic characteristics and hydration kinetic parameters of MOCP with different contents and types of gypsum are investigated. The results show that the incorporation of gypsum to the MOCP reduces the cumulative heat release of the MOCP and prolongs the induction and acceleration periods. The hydration kinetic parameters also show that the scale factor (A) of MOCP decreases with increasing gypsum content. Incorporation of natural gypsum (NG) to MOCP reduces its nucleation rate and growth rate, while an appropriate amount of flue gas desulfurization gypsum can provide nucleation sites and increase its growth rate. The early-age compressive strength of the gypsum-modified MOCP is reduced due to the reduction in the reaction product (5-phase), but NG can act as a micro-aggregate to alleviate its negative impact on the sample strength.
Nowadays, steam curing has become an effective way to produce high early strength concrete prefabricated elements. However, this curing regime has been proved to lead to the heat damage on the ...microstructures and properties of concrete. Therefore, how to characterize the heat damage, and the impact of heat damage on the durability of concrete is a key issue. In this study, three treatment temperatures were employed to study the heat damage of steam-cured concrete. In addition, the surface gas permeability (SGP), water intentional spraying tests (WIS), pore structure, TG-DSC and SEM were measured to analyze the effects of curing regimes on performance of steam-cured concrete. The results indicate that there are differences in the surface and interior of steam-cured concrete, and surface permeability (SGP and WIS) can characterize these differences. Meanwhile, high temperature steam curing is detrimental to the long-term impermeability of concrete, and surface treatment can improve this phenomenon. The surface covered by geotextile has the lowest permeability and relatively dense microstructures.
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•Surface gas permeability, water intentional spraying and pore structure of steam-cured concrete was tested.•Surface permeability (gas and water) was used to quantitatively characterize the heat damage of concrete by steam curing.•The change of the surface permeability indicates the heat damage in steam-cured concrete.•Treatment temperature and surface treatment have a significant effect on the surface permeability of steam-cured concrete.
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