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1.
J Matern Fetal Neonatal Med ; 37(1): 2389979, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-39284760

RESUMO

OBJECTIVES: Pre-eclampsia (PE) and gestational hypertension (GH) are two different categories of hypertensive disorders of pregnancy. Given earlier observational research, the relationship between sex hormone-binding globulin (SHBG) and a higher risk of GH/PE is still up for dispute. Hence, the present investigation aimed to examine the possible link between SHBG and the likelihood of GH/PE. METHODS: As a first stage, single nucleotide polymorphisms from summary-level genome-wide association studies were tightly screened using quality-control techniques. Afterward, we utilized a two-sample Mendelian randomization (MR) study to examine the causal impact of SHBG on the likelihood of GH/PE. There was no indication of a relationship between blood SHBG level (n = 214,989) and GH/PE (1864 cases and 461,069 controls) in the initial study. Consensus results were obtained from the replicated analysis, which utilized MR estimates based on serum SHBG level(n = 214,989) for GH (4255 cases and 114,735 controls). RESULTS: The findings did not indicate any proof of a cause-and-effect connection between SHBG and the likelihood of GH/PE (odds ratio [OR] = 0.99, 95% confidence interval [CI] = 0.999 - 1.00, p = .34). Replicate analysis also revealed similar patterns (OR = 0.92, 95%CI = 0.82-1.05, p = .21). The above findings were demonstrated to have a strong level of robustness. CONCLUSIONS: The findings of this research did not offer definitive proof to endorse the idea that SHBG has a direct causal impact on the likelihood of GH/PE, which goes against numerous widely accepted observational studies. To ascertain the potential processes behind the relationships seen in observational studies, more investigation is needed.


Assuntos
Estudo de Associação Genômica Ampla , Hipertensão Induzida pela Gravidez , Análise da Randomização Mendeliana , Polimorfismo de Nucleotídeo Único , Pré-Eclâmpsia , Globulina de Ligação a Hormônio Sexual , Humanos , Feminino , Globulina de Ligação a Hormônio Sexual/análise , Gravidez , Pré-Eclâmpsia/genética , Pré-Eclâmpsia/sangue , Pré-Eclâmpsia/epidemiologia , Hipertensão Induzida pela Gravidez/genética , Hipertensão Induzida pela Gravidez/sangue , Hipertensão Induzida pela Gravidez/epidemiologia , Estudos de Casos e Controles
2.
Materials (Basel) ; 17(13)2024 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-38998211

RESUMO

Ultra-High Toughness Cementitious Composite (UHTCC) represents a composite material meticulously engineered on the foundation of micromechanical principles. The multi-crack cracking and strain-hardening characteristics of UHTCC enable it to be applied to orthotropic steel decks to control the crack width. Different from most studies which only focus on hybrid fiber or fatigue characteristics, this paper studies the influence of hybrid fiber content on static mechanical properties, flexural toughness, and flexural fatigue characteristics of UHTCC under different stress levels. The compressive and flexural strength, bending toughness, and fatigue damage of UHTCC under different fiber ratios were compared, and the fatigue properties of hybrid fiber UHTCC were verified. The results reveal that hybrid fiber exerts a more pronounced effect on toughness, augmenting the maximum folding ratio by 23.7%. Single-doped steel fiber UHTCC exhibits a characteristic strain-softening phenomenon attributable to inadequate fiber content, whereas the bending toughness index of hybrid fiber UHTCC surpasses that of SF1.5P0 by 18.6%. Under low-stress conditions, UHTCC demonstrates a nearly threefold increase in bending fatigue life with a mere 1% steel fiber content, while the influence of polyvinyl alcohol (PVA) fiber on fatigue life is more significant: with an increase of only 1/5 volume content, the fatigue life increased by 29.8%, reaching a maximum increase of 43.2% at 1/4 volume content. Furthermore, the fatigue damage accumulation curve of UHTCC follows a three-stage inverted S-shaped trajectory. The inclusion of PVA fiber facilitates early initiation of stable cracking during the fatigue failure process, thereby advancing the entire strain stability development stage and mitigating external load forces through the proliferation of micro-cracks. Consequently, compared to SF1P0, the ε0 of SF1P5 experiences a significant increase, reaching 143.43%.

3.
Materials (Basel) ; 17(12)2024 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-38930327

RESUMO

As a new type of backfill material, Self-compacting solidified soil (SCSS) takes the abandoned slurry of cast-in-place piles after dewatering and reduction as the main raw material, which brings a problem of coordinating the working performance with the mechanical property under the condition of high mobility. In this paper, hydroxypropyl methyl cellulose (HPMC) and metakaolin were introduced as additives to solve this problem. First, the workability and mechanical properties of SCSS were regulated and optimized by means of the water seepage rate test, the flowability test, and the unconfined compressive strength test. Second, this study also used X-ray diffraction (XRD) and scanning electron microscopy (SEM) to investigate the effects of HPMC and metakaolin on the physical phase and microstructure of SCSS. In this way, the results showed that there was a significant impact on the flowability of SCSS, that is, when the dosage reached 0.3%, the water seepage rate of SCSS was reduced to less than 1%, and the compressive strength at 7 days reached its peak. At the same time, HPMC weakened the strength growth of SCSS in the age period of 7 days to 14 days. However, the addition of metakaolin promoted its compressive strength. XRD analysis showed that the additives had no significant effects on the physical phases. And, from the SEM results, it can be seen that although the water-retaining effect of HPMC makes hydration of cement more exhaustive, more ettringite (AFt) can be observed in the microstructure. In addition, it can be observed that the addition of metakaolin can generate more hydrated calcium silicate (C-S-H) due to the strong surface energy possessed by metakaolin. As a result of the above factors, SCSS filled the voids between particles and improved the interface structure between particles, thus enhanced the compressive strength.

4.
Int J Genomics ; 2024: 5681174, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38269194

RESUMO

Water deficit is a key limiting factor for limiting yield in maize (Zea mays L.). It is crucial to elucidate the molecular regulatory networks of stress tolerance for genetic enhancement of drought tolerance. The mechanism of drought tolerance of maize was explored by comparing physiological and transcriptomic data under normal conditions and drought treatment at polyethylene glycol- (PEG-) induced drought stress (5%, 10%, 15%, and 20%) in the root during the seedling stage. The content of saccharide, SOD, CAT, and MDA showed an upward trend, proteins showed a downward trend, and the levels of POD first showed an upward trend and then decreased. Compared with the control group, a total of 597, 2748, 6588, and 5410 differentially expressed genes were found at 5%, 10%, 15%, and 20% PEG, respectively, and 354 common DEGs were identified in these comparisons. Some differentially expressed genes were remarkably enriched in the MAPK signaling pathway and plant hormone signal transduction. The 50 transcription factors (TFs) divided into 15 categories were screened from the 354 common DEGs during drought stress. Auxin response factor 10 (ARF10), auxin-responsive protein IAA9 (IAA9), auxin response factor 14 (ARF14), auxin-responsive protein IAA1 (IAA1), auxin-responsive protein IAA27 (IAA27), and 1 ethylene response sensor 2 (ERS2) were upregulated. The two TFs, including bHLH 35 and bHLH 96, involved in the MAPK signal pathway and plant hormones pathway, are significantly upregulated in 5%, 10%, 15%, and 20% PEG stress groups. The present study provides greater insight into the fundamental transcriptome reprogramming of grain crops under drought.

5.
Materials (Basel) ; 16(22)2023 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-38005026

RESUMO

This study explores the mechanical properties, as well as the water-reducing and setting delay mechanism, of a novel xylonic acid-based water reducer applied to cementitious materials. Four xylonic acid water reducers were synthesized in this study: XACa (PX) from pure xylose, XACa (HS) from hemicellulose hydrolysate, XANa (PX) from pure xylose, and XANa (HS) from hemicellulose hydrolysate. These were generated through the whole-cell catalysis of Gluconobacter oxydans bacteria, using pure xylose and hemicellulose hydrolysate as substrates. The findings indicate that the xylonic acid-based water reducer can attain a water-reducing capability between 14% and 16% when the dosage (expressed as a mass fraction of cement) is roughly 0.2%. In initial and final setting tests, XACa (PX) demonstrated a pronounced retarding influence at admixture levels below 0.15%, reaching its apex at 0.10%. This delayed the initial setting time by 76% and the final setting time by 136% relative to the control group. However, a slight pro-setting effect was noted beyond a 0.2% dosage. In the compressive and flexural tests of concrete, under the same slump, the XA group improved its mechanical properties by 5% to 10% compared to the SodiuM lignosulfonate (SL) group. In the air content and chloride ion migration resistance tests, the XA group reduced the air content by 38% compared to the SL group, but also increased the data of rapid chloride migration (DRCM) by 16%. Characterization studies revealed that the carboxyl and hydroxyl groups in xylonic acid undergo chemisorption with the Si-O bonds on the surface of cement particles. These groups interact with the Si-O bonds on cement particles, contributing to water-reducing effects and delaying the setting process by impeding Ca2+ ion aggregation in the calcium-silicate-hydrate gel. Its significant water-reducing effect, adjustable setting time, and excellent mechanical and durability properties suggest its viability as an alternative to lignosulfonate series water-reducing agents.

6.
Materials (Basel) ; 16(17)2023 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-37687484

RESUMO

Superhydrophobic coating ice suppression is an advanced and durable technology that shows great potential for application on pavements. Although many researchers have conducted experimental and theoretical validations to confirm the effectiveness of superhydrophobic surfaces in actively suppressing ice formation, there are still some who remain skeptical. They argue that the roughness of the surface may increase ice adhesion due to the mechanical interlocking effect of condensation droplets in low-temperature and high-humidity environments. In this study, we present a comprehensive investigation of a novel superhydrophobic coating specifically designed for pavement surfaces, aiming to address the question of its active anti-icing/ice-sparing capabilities in a condensing environment. The changes in contact angle before and after condensation for four material surfaces with varying wettability were investigated, as well as the morphology and ice adhesion of liquid water after it freezes on the material surface. The findings reveal that the proposed superhydrophobic coating for pavements effectively prevents condensate droplets from infiltrating the surface structure, resulting in delaying the surface icing time and reducing the attachment strength of the ice.

7.
Herz ; 2023 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-37721628

RESUMO

BACKGROUND: This study aimed to screen out the potential diagnostic biomarkers for atherosclerosis (AS). METHODS: We downloaded the gene expression profiles GSE66360, GSE28829, GSE41571, GSE71226, and GSE100927 from the Gene Expression Omnibus (GEO) database. The differentially expressed genes (DEGs) were identified using the "limma" package in R. Weighted gene co-expression network analysis (WGCNA) was applied to reveal the correlation between genes in different samples. Subsequently, Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analyses were performed. The interaction pairs of proteins were retained by the STRING database, and the protein-protein interaction (PPI) network was visualized with the hub genes. Finally, the R packages "ggpubr" and "preprocessCore" were used to analyze immune cell infiltration. RESULTS: In total, 40 overlapping genes both in GSE66360 and GSE28829 were found to be related to the occurrence of AS. Further, the top 10 network hub genes including TYROBP, CSF1R, TLR2, CD14, CCL4, FCER1G, CD163, TREM1, PLEK, and C5AR1 were identified as significant key genes. Moreover, four genes (TYROBP, CSF1R, FCGR1B, and CD14) were verified that could efficiently diagnose AS. Finally, the gene TYROBP was found to have a strong correlation with immune-infiltrating cells. CONCLUSION: Our study identified four genes (TYROBP, CSF1R, FCGR1B, and CD14) that may be effective biomarkers for AS, with the potential to guide the clinical diagnosis of AS.

8.
Materials (Basel) ; 15(24)2022 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-36556515

RESUMO

Innovative sustainable techniques for transportation infrastructure enhancement have been proposed in recent decades [...].

9.
Front Genet ; 13: 1038948, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36506330

RESUMO

Maize (Zea mays L.) is the most important food security crop worldwide. Northern corn leaf blight (NCLB), caused by Exserohilum turcicum, severely reduces production causing millions of dollars in losses worldwide. Therefore, this study aimed to identify significant QTLs associated with NCLB by utilizing next-generation sequencing-based bulked-segregant analysis (BSA). Parental lines GML71 (resistant) and Gui A10341 (susceptible) were used to develop segregating population F2. Two bulks with 30 plants each were further selected from the segregating population for sequencing along with the parental lines. High throughput sequencing data was used for BSA. We identified 10 QTLs on Chr 1, Chr 2, Chr 3, and Chr 5 with 265 non-synonymous SNPs. Moreover, based on annotation information, we identified 27 candidate genes in the QTL regions. The candidate genes associated with disease resistance include AATP1, At4g24790, STICHEL-like 2, BI O 3-BIO1, ZAR1, SECA2, ABCG25, LECRK54, MKK7, MKK9, RLK902, and DEAD-box ATP-dependent RNA helicase. The annotation information suggested their involvement in disease resistance-related pathways, including protein phosphorylation, cytoplasmic vesicle, protein serine/threonine kinase activity, and ATP binding pathways. Our study provides a substantial addition to the available information regarding QTLs associated with NCLB, and further functional verification of identified candidate genes can broaden the scope of understanding the NCLB resistance mechanism in maize.

11.
Theor Appl Genet ; 129(4): 753-765, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26849239

RESUMO

KEY MESSAGE: Molecular characterization information on genetic diversity, population structure and genetic relationships provided by this research will help maize breeders to better understand how to utilize the current CML collection. CIMMYT maize inbred lines (CMLs) have been widely used all over the world and have contributed greatly to both tropical and temperate maize improvement. Genetic diversity and population structure of the current CML collection and of six temperate inbred lines were assessed and relationships among all lines were determined with genotyping-by-sequencing SNPs. Results indicated that: (1) wider genetic distance and low kinship coefficients among most pairs of lines reflected the uniqueness of most lines in the current CML collection; (2) the population structure and genetic divergence between the Temperate subgroup and Tropical subgroups were clear; three major environmental adaptation groups (Lowland Tropical, Subtropical/Mid-altitude and Highland Tropical subgroups) were clearly present in the current CML collection; (3) the genetic diversity of the three Tropical subgroups was similar and greater than that of the Temperate subgroup; the average genetic distance between the Temperate and Tropical subgroups was greater than among Tropical subgroups; and (4) heterotic patterns in each environmental adaptation group estimated using GBS SNPs were only partially consistent with patterns estimated based on combining ability tests and pedigree information. Combining current heterotic information based on combining ability tests and the genetic relationships inferred from molecular marker analyses may be the best strategy to define heterotic groups for future tropical maize improvement. Information resulting from this research will help breeders to better understand how to utilize all the CMLs to select parental lines, replace testers, assign heterotic groups and create a core set of breeding germplasm.


Assuntos
Genótipo , Vigor Híbrido , Polimorfismo de Nucleotídeo Único , Zea mays/genética , DNA de Plantas/genética , Frequência do Gene , Endogamia , Melhoramento Vegetal , Análise de Sequência de DNA
12.
PLoS One ; 10(7): e0132379, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26148055

RESUMO

Genomic selection is a promising research area due to its practical application in breeding. In this study, impact of realized genetic relationship and linkage disequilibrium (LD) on marker density and training population size required was investigated and their impact on practical application was further discussed. This study is based on experimental data of two populations derived from the same two founder lines (B73, Mo17). Two populations were genotyped with different marker sets at different density: IBM Syn4 and IBM Syn10. A high-density marker set in Syn10 was imputed into the Syn4 population with low marker density. Seven different prediction scenarios were carried out with a random regression best linear unbiased prediction (RR-BLUP) model. The result showed that the closer the real genetic relationship between training and validation population, the fewer markers were required to reach a good prediction accuracy. Taken the short-term cost for consideration, relationship information is more valuable than LD information. Meanwhile, the result indicated that accuracies based on high LD between QTL and markers were more stable over generations, thus LD information would provide more robust prediction capacity in practical applications.


Assuntos
Desequilíbrio de Ligação , Modelos Genéticos , Seleção Genética , Zea mays/genética
13.
Artigo em Inglês | MEDLINE | ID: mdl-24146506

RESUMO

UNLABELLED: The objectives of this study were to learn about the characteristics and rules of the occurrence of adverse reactions caused by lactam antibiotics and provide a reference for clinical drug use. METHODS: A retrospective study was made to analyse the 113 case reports of adverse reactions caused by ß-lactam antibiotics collected in our hospital between 2007 and 2009. RESULTS: 113 cases of ADR involved 17 kinds of ß-lactam antibiotics, headed by ceftriaxone sodium. The most common manifestation was skin and accessory damage; nervous system and gastrointestinal system damage were also easier to find, and the administration route was mainly intravenous infusion. CONCLUSION: The clinical application of ß-lactam antibiotics should pay attention to adverse reaction monitoring and rational drug use to reduce the incidence of adverse reactions.


Assuntos
Antibacterianos/efeitos adversos , beta-Lactamas/efeitos adversos , Adolescente , Adulto , Antibacterianos/administração & dosagem , Ceftriaxona/efeitos adversos , Criança , Feminino , Trato Gastrointestinal/efeitos dos fármacos , Humanos , Masculino , Pessoa de Meia-Idade , Sistema Nervoso/efeitos dos fármacos , Estudos Retrospectivos , Pele/efeitos dos fármacos , Adulto Jovem , beta-Lactamas/administração & dosagem
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