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Auxin plays an essential role in regulating Arabidopsis growth and development. YUCCA (YUC) family genes encode flavin monooxygenases, which are rate-limiting enzymes in the auxin biosynthetic pathway. Previous studies showed that YUC8 overexpression (YUC8 OE), as well as ectopic expression of YUC8 driven by GL2 (GLABRA 2) and TT12 (TRANSPARENT TESTA 12) promoters, which are specifically expressed in the epidermis and inner seed integument, respectively, produced larger seeds compared to the Col. However, the impact of these transgenic lines on the vegetative growth of Arabidopsis remains unclear. Here, we show that the GL2pro:YUC8-GFP and TT12pro:YUC8-GFP transgenic plants produce a moderate excessive auxin accumulation phenotype compared to the YUC8 OE. These two transgenic lines produced smaller rosette and leaf, higher plant height, fewer branches, and longer siliques. These data will provide a basis for the study of the relationship between the ectopic expression of auxin synthesis genes and crop yield.

Auxins play crucial regulatory roles in plants coping with cadmium (Cd) stress. However, the regulatory mechanism by which auxins alleviate Cd toxicity in tomato seedlings remains unclear. Here, we demonstrate that exposure to Cd stress leads to dynamic changes in the auxin response in tomato roots, characterized by an initial increase followed by a subsequent weakening. Under Cd stress, tomato seedlings show primary root- and hypocotyl-growth inhibition, accompanied by the accumulation of Cd and reactive oxygen species (ROS) in the roots. The exogenous application of 1-naphthylacetic acid (NAA) does not mitigate the inhibitory effect of Cd toxicity on primary root growth, but it does significantly enhance lateral root development under Cd stress. Auxin transport inhibitors, such as 1-N-naphthylphthalamic acid (NPA) and 2,3,5-triiodobenoic acid (TIBA), aggravate the growth inhibition of primary roots caused by Cd stress. Additionally, lateral root development was inhibited by NPA. However, applying auxin synthesis inhibitors L-kynurenine (kyn) and yucasin alleviated the tomato root growth inhibition caused by Cd stress; between them, the effect of yucasin was more pronounced. Yucasin mitigates Cd toxicity in tomato seedlings by reducing Cd2+ absorption and auxin accumulation, strengthening ROS scavenging, and reducing cell death in roots. These observations suggest that yucasin potentially mitigates Cd toxicity and improves the tolerance of tomato seedlings to Cd stress.

Over 40% of arable land in the world is acidic. Al stress has become a global agricultural problem affecting plant growth and limiting crop production in acidic soils. Plants have evolved different regulatory mechanisms of adaptation to exogenous environmental challenges, such as Al stress, by altering their growth patterns. In the past decades, several key genes involved in plant response to Al stress and the mechanism of Al detoxification have been revealed. However, the signaling pathways of plant response to Al stress and the regulatory mechanism of plant Al tolerance remain poorly understood. In this review, we summarized the findings of recent studies on the plant Al tolerance mechanism and the molecular regulation mechanism of phytohormones in response to Al stress. This review improves our understanding of the regulatory mechanisms of plants in response to Al stress and provides a reference for the breeding of Al-tolerant crops.

Recommendations promoted worldwide have suggested a period of protection lasting more than 20 years against hepatitis B (HB) following primary immunization. Starting in 1987, universal HB vaccinations were carried out in Long An County, Guangxi Province, one of the earliest counties in which plasma-derived HB vaccine was delivered to newborns across China. Data collection targeted toward understanding the long term (26–33 years since primary immunization) immune effects of the plasma-derived HB vaccine was conducted in 2015; a second data collection was carried out in 2019 to assess seroconversion in the same cohort. This study qualitatively compared positive vs negative results and quantitatively assessed HB biomarkers – HB surface antigen (HBsAg), antibody to HBsAg (anti-HBs), HB e-antigen (HBeAg), antibody to HBeAg (anti-HBe), and antibody to HB core antigen (anti-HBc) – in serum 26–33 years after the full initial course of HB vaccination, then analyzed anti-HBs seroconversion using the two-phase sampling method in the same cohort and calculated the anti-HBs seroconversion rate from 2015 to 2019. The protective sero-conversion rate (anti-HBs ≥10mIU/mL) was 37.6% (192/511); the HBsAg-positive rate was 5.3% (27/511); the anti-HBs mean geometric titer (GMT) was 11.1 mIU/mL. Among the 143 participants involved in both 2015 and 2019 data collections, the seroconversion rate was 3.5% (5/143); two individuals had protective anti-HBs levels in 2015. These findings indicate that anti-HBs status can be seroconverted to a protective concentration level 4 years earlier in a high HBV epidemic region. The role of genomic mutations and the disappearance of immune memory and seroconversion should be investigated.

The Ultra Performance Liquid Chromatography-Triple-Time of Flight Mass Spectrometer (UPLC-Triple-TOF-MS/MS) based platform was developed to investigate the serum metabolic profile associated with the growth performance in Chinese softshell turtle fed with the diet added with Traditional Chinese Medicines (TCMs) feeding additive. 0.0%, 1.0%, 2.0%, 3.0%, 4.0% of TCMs were added to the base ration of the control group (CG), TCMs treatment group1 (TG1), TCMs treatment group2 (TG2), TCMs treatment group3 (TG3) and TCMs treatment group4 (TG4), respectively. Compared with control group (CG), the weight gain and special growth ratio firstly increased and lately decreased with increased dietary TCMs levels. The highest weight gain (5.824 ± 1.205) and specific growth rate (3.887 ± 0.367) were found in the TCMs treatment group 2 (TG2) (P < 0.05), and the lowest feed conversion ratio (1.785±0.015) also appeared in the TG2 group (P < 0.05). In the metabolomics assay, a total of 795 (VIP> 1) out of 3089 variable metabolites were significantly different between the TG2 and CG. 43 potential biomarkers between TG2 and CG groups were finally screened out on the basis of VIP > 1 and P < 0.05. The potential networks and pathways for the model were explored using MetaboAnalyst. A total of 43 potential biomarkers were confirmed involving thirteen different metabolic pathways. Following the diet added with 2% TCMs feeding additive, five metabolic pathways were affected, these included the following: phenylalanine, tyrosine and tryptophan biosynthesis, tyrosine metabolism, cysteine and methionine metabolism and arginine biosynthesis. This study indicated that the dietary supplementation TCMs as feed additives could influence the growth performance of the healthy juvenile turtles, and the optimal dose of supplementing TCMs to juvenile turtleswas 20 g/kg in diet.

In compressed sensing (CS), the absolute value of the inner product of signal and atom (or dictionary) is used to select atom (or dictionary); the atoms (or dictionaries) with larger absolute values of inner product are selected to decompose and reconstruct signals. This characteristic usually makes it impossible to distinguish the edges of objects (or targets) in some complex cases, especially when the density of objects is very high. For example: let signal x1 = [···00110110···]T, x2 = [⋯001110100⋯]T; ψ1, ψ2, ψ3 and ψ4 denote several sparse basis matrices (i.e., sparse dictionaries); ψ1i = [⋯00000100⋯]T, ψ2j = [⋯00110000⋯]T, ψ3k = [⋯00111000⋯]T, and ψ4l = [⋯00111110⋯]T are the sparse bases (i.e., atoms) from these sparse basis matrices (i.e., dictionaries), respectively. For signal x1, ψ4l (or ψ4) is selected instead of ψ2j (or ψ2); likewise, for x2, ψ4l (or ψ4) will be selected instead of ψ3j(or ψ3) and ψ1i (or ψ1). This causes the edge of the object to be unrecognizable. Another example is in lp regularization, it is not necessarily the optimal case: the smaller the value of ||Ψd-1 x||0, the better the sparse basis matrix (i.e., dictionary), or the larger the weighing parameter. At present, the inner product is used to process almost all signals in CS. Choosing the dictionary that matches the signal best rather than the dictionary with the maximum inner product value can reconstruct the signal more accurately. In order to overcome the above shortcoming, we propose a fully automatic radar image processing algorithm of CS based on arbitrary block statistical histogram and dynamic dictionary. We use arbitrary block statistical histogram to calculate the non-zero block numbers of different sizes, which can better choose the appropriate sparse base (or dictionary) for the signal. Furthermore, the better measurement vector y can be obtained, and the signal can be reconstructed more accurately than the state-of-the-art methods at the receiving end. To realize the proposed method, we construct objective functions and flow charts for noiseless and noisy signals, respectively. In our method, for noiseless signal, discarding the sub-images that do not contain objects can reduce running time; for noisy signal, according to the theory of wavelet, choosing the appropriate wavelet (i.e., wavelet basis) can usually suppress noise. Our proposed algorithm can overcome the above shortcoming of CS in using the absolute value of the inner product, reduce running time, suppress-noise, and improve the signal-to-noise ratio (SNR). The simulation results show that our method is superior to the state-of-the-art methods.

Microwave heating of water-bearing coal can promote pore water evaporation. The pores are broken under the action of steam pressure, increasing the permeability of the coal. This study is aimed at investigating the mechanism of permeability improvement of water-bearing coal rock by microwave steam explosion. First, a microwave oven was used to irradiate and heat five groups of coal rock with different water contents; the NMR test was then conducted on the heated sample. Second, the internal vapor pressure and temperature changes during the heating process were obtained through the T-connector for samples with different water contents. Finally, a numerical experiment was used to explore the deformation characteristics of pores under three filling conditions. The experimental results showed that the total porosity increased significantly when the water content of coal increased from 0% to 8%, while the permeability increased by nearly 4.78 times. The extreme value of gas pressure inside the sample showed an increasing trend. The gas pressure and temperature were in line with the equation of state for an ideal gas during the rising phase. Numerical experiments showed that the pore boundary shrunk inward under vacuum conditions, and compressive stress appeared at the tip. The saturated humid air and liquid water conditions expanded the pore boundaries outward and caused tensile stress at the tip, with the latter being nearly 2.3 times larger than the former, making it more conducive to the development of pores. The findings of this study can be used as a reference value for the expansion of coalbed methane extraction technology.

The weak interlayers in an open-pit blasting bench affect the uniform distribution of explosive energy. To explore the mechanistic influence of a weak interlayer on the effect of blasting, 9 sets of numerical blasting experiments were constructed using the orthogonal experiment method. The degree of bench crushing after blasting, the maximum velocity of the rock mass at 0.05 s, and the displacement of the back of the bench were thus investigated. The analysis revealed that the impact of the thickness of the weak interlayer, its wave impedance, and its location of occurrence on the bench blasting indicated an ordered decreasing effect. Based on this, the evaluation method for the master weak interlayer and the design plan of the specific charge structure were proposed. The evaluated design proposals were verified through both numerical and field tests. The research results will provide a scientific basis to determine a reasonable charge structure of the bench blasting of rock masses containing weak interlayers.

Various geotechnical experiments have used gypsum-cemented analog geotechnical materials. However, this material needs a long curing time, and the target strength is not easy to control. Therefore, this research adopted microwave heating as the curing method for this kind of material. Objectively, the authors investigated the variations in the material strength versus heating power and heating time. On this basis, we clarified the influence mechanism of microwaves on the strength of analog materials by analyzing material temperature, moisture content, and microstructure, which eventually led to an experimental control method for rapid strengthening of microwave field-controlled gypsum-cemented analog materials. Consequently, we drew the following conclusions. The stable strength of the material under high-power microwave curing was much lower than that under natural curing, while the material strength under low-power microwave curing was the closest to the material under natural curing.

Genes essential for gametophyte development and fertilization have been identified and studied in detail; however, genes that fine-tune these processes are largely unknown. Here, we characterized an unknown Arabidopsis gene, GTP-BINDING PROTEIN RELATED1 (GPR1). GPR1 is specifically expressed in ovule, pollen, and pollen tube. Enhanced green fluorescent protein-tagged GPR1 localizes to both nucleus and cytoplasm, and it also presents in punctate and ring-like structures. gpr1 mutants exhibit no defect in gametogenesis and seed setting, except that their pollen grains are pale in color. Scanning electron microscopy analyses revealed a normal patterned but thinner exine on gpr1 pollen surface. This may explain why gpr1 pollen grains are pale. We next examined whether GPR1 mutation affects post gametogenesis processes including pollen germination, pollen tube growth, and ovule senescence. We found that gpr1 pollen grains germinated earlier, and their pollen tubes elongated faster. Emasculation assay revealed that unfertilized gpr1 pistil expressed the senescence marker PBFN1:GUS (GUS: a reporter gene that encodes β-glucuronidase) one-day earlier than the wild type pistil. Consistently, ovules and pollen grains of gpr1 mutants showed lower viability than those of the wild type at 4 to 5 days post anthesis. Together, these data suggest that GPR1 functions as a negative regulator of pollen germination, pollen tube growth, and gametophyte senescence to fine-tune the fertilization process. [ABSTRACT FROM AUTHOR]