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This article discusses the detection of the cfr gene in Citrobacter braakii and the characterization of two cfr-carrying plasmids from a chicken farm in Jiangxi, China. The cfr gene is a multidrug resistance gene that has spread globally in Gram-positive and Gram-negative bacteria. The study identified three cfr-positive strains, including one C. braakii and two E. coli strains, and found that the cfr gene was located on different plasmids in these strains. The article highlights the widespread distribution and rapid dissemination of cfr in animal-derived bacteria and emphasizes the need for monitoring and control of cfr plasmids. [Extracted from the article]

Chickpeas (Cicer arietinum L.) are an important legume crop known for their rich nutrient content, including proteins, carbohydrates, and minerals. Thus, they are enjoyed by people worldwide. In recent years, the production scale of chickpeas has been growing gradually. The planting area of chickpeas represents roughly 35–36% of the total planting area, and the output of the beans is roughly 47–48%. However, the growth and development process of chickpeas is limited by a number of factors, including high temperature, drought, salt stress, and so forth. In particular, high temperatures can reduce the germination rate, photosynthesis, seed setting rate, and filling rate of chickpeas, restricting seed germination, plant growth, and reproductive growth. These changes lead to a decrease in the yield and quality of the crop. Heat shock proteins (HSPs) are small proteins that play an important role in plant defense against abiotic stress. Therefore, in the present study, HSP20 gene family members were identified based on the whole-genome data of chickpeas, and their chromosomal positions, evolutionary relationships, promoter cis-acting elements, and tissue-specific expression patterns were predicted. Subsequently, qRT-PCR was used to detect and analyze the expression characteristics of HSP20 genes under different temperature stress conditions. Ultimately, we identified twenty-one HSP20 genes distributed on seven chromosomes, and their gene family members were found to be relatively conserved, belonging to ten subfamilies. We also found that CaHSP20 promoter regions have many cis-acting elements related to growth and development, hormones, and stress responses. In addition, under high-temperature stress, the relative expression of CaHSP20-17, CaHSP20-20, CaHSP20-7, CaHSP20-3, and CaHSP20-12 increased hundreds or even thousands of times as the temperature increased from 25 °C to 42 °C. Among them, excluding CaHSP20-5, the other five genes all contain 1-2 ABA cis-regulatory elements. This finding indicates that CaHSP20s are involved in the growth and development of chickpeas under heat stress, and the mechanisms of their responses to high-temperature stress may be related to hormone regulation. The results of the present study lay the foundation for exploring HSP20 gene family resources and the molecular mechanisms of heat resistance in chickpeas. Our results can also provide a theoretical basis for breeding high-temperature-resistant chickpea varieties and provide valuable information for the sustainable development of the global chickpea industry. [ABSTRACT FROM AUTHOR]

Hemp seeds are consumed in "Bama longevity villages" in China and are believed to contribute to the locals' longevity. However, the molecular breeding of hemp seeds is limited due to our lack of understanding of molecular regulation and metabolite accumulation at different maturity stages. Here, we conducted metabolomic and transcriptomic analyses of hemp seeds from the Bama region at four maturity stages (S1 to S4). In total, 1231 metabolites of 11 classes were detected in hemp seeds from S1–S4, including 233 flavonoids, 214 phenolic acids, 159 lipids, 118 amino acids and derivatives, 100 alkaloids, 100 organic acids, 71 nucleotides and derivatives, 43 lignans and coumarins, 14 terpenoids, 13 tannins, and 166 others. The metabolomic analysis of hemp seeds (from the Bama region) revealed a higher number of flavonoid metabolites compared with seven other varieties from other regions in China. Hemp seeds are rich in metabolites like cannflavin, trigonelline, citric acid, vitexin, choline alfoscerate, and choline, which may potentially contribute to the longevity of the Bama people. Through transcriptomic and metabolomic analyses, a gradual decrease in the overall expression pattern of genes and metabolite accumulation was observed during seed maturation. Weighted gene co-expression network analysis revealed that two genes (ncbi_115696993 and ncbi_115706674) are involved in regulating main metabolites, while transcription factor association analysis revealed that three transcription factor genes (MYB, NAC, and GRAS) are also involved in regulating the metabolites. The expression pattern of these five candidate genes was further verified by qPCR. Our study provides valuable insights into the metabolic substances during seed maturation and identifies candidate genes that could be utilized for future genetic engineering to enhance the endogenous biosynthesis of health-promoting metabolites in hemp seeds, potentially leading to improved nutritional and medicinal properties. [ABSTRACT FROM AUTHOR]

Purpose: The purpose of this paper is to obtain a constitutive model of cement-based material in the rheological stage, which owns the different water-cement ratio (w/c) and temperature and have a significant impact on the workability of concrete materials. Design/methodology/approach: It is introduced a modified Arrhenius equation into the Herschel–Bulkley model, which is widely applied in rheological analysis and constructed an ordinary differential equation (ODE) of w/c from the Navier–Stokes equation. By solving the ODE, an approximate constitutive relation of cement-based materials included w/c and temperature is derived. Compared with the experimental results, the present model is validated. Findings: The shear stress and shear rate curves with different w/c and temperature are simulated by the present method, and the present model can be applied to analyze the changes of apparent viscosity in cement-based material slurry as the w/c and temperature varying. Originality/value: This work gives a mathematical model, which can effectively approximate the shear stress–shear rate relation with different w/c and temperature in the rheological stage of cement-based material. [ABSTRACT FROM AUTHOR]