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In this paper, the bubble nucleation process of water was studied by molecular dynamics (MD) simulation. The nucleation mechanism of water on a grooved substrate was revealed from the perspective of hydrogen bond and energy change, and the effect of system pressure on nucleation was studied. The results show that the process of bubble nucleation of water molecules is essentially a process in which the thermal motion of water molecules gradually intensifies and the hydrogen bond continues to break with the increase in kinetic energy. As the hydrogen bond breaks, the kinetic energy of the water molecules is continuously converted to intermolecular potential energy. By analyzing the composition of the hydrogen bond energy, it is found that the electrostatic energy is much greater than the van der Waals energy, so the water nucleation process mainly overcomes the electrostatic force between molecules. With the gradual increase of pressure, although the kinetic energy distribution of molecules does not change significantly, it will cause the potential energy of water molecules to decrease significantly and then lead to the increase of the energy barrier that needs to be crossed for nucleation. Meanwhile, the rise of the nucleation barrier may result in the absence of obvious initial vapor nuclei inside the liquid so that the number of hydrogen bonds cannot be rapidly reduced, which is not conducive to boiling nucleation. The results of this study provide important implications for further understanding of the nucleate boiling process of water.
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Herein, we disclose a palladium-catalyzed cross-coupling of aryl bromides and chlorides with trimethylsilylalkynes under mild reaction conditions. This method utilizes commercially available and air stable palladium precatalysts and avoids the use of copper cocatalysts. Moreover, it allows for the synthesis of a wide range of disubstituted alkynes in high yields with excellent functional group tolerance. The utility of the developed method was further demonstrated via the late-stage alkynylation of pharmaceuticals and natural bioactive compounds.
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Laminarin (LAM) is widely used as an immunopotentiator in aquaculture, but its protective mechanism is still unclear. In this study, the effects of LAM on the growth performance and resistance against Pseudomonas plecoglossicida of large yellow croaker were studied in vitro and in vivo. The 42 d-feeding trial in large yellow croaker showed that dietary LAM could obviously promote the fish growth by improving the weight gain rate (WGR), specific growth rate (SGR), and feed conversion rate (FCR). Dietary LAM could also improve the survival rate of large yellow croakers subjected to P. plecoglossicida infection, and 500 mg/kg LAM produced the highest relative percent survival (RPS) of 35.00 %. LAM improved fish antioxidant level by enhancing serum total antioxidant capacity (T-AOC) and superoxide dismutase (SOD) activity, and reducing malondialdehyde (MDA) content. In addition, LAM also improved fish innate immunity by increasing serum acid phosphatase (ACP) and alkaline phosphatase (AKP) activities and complement 3 (C3) content under P. plecoglossicida infection. What is more, on 9 d post P. plecoglossicida challenge, LAM could significantly decrease the bacteria load in head kidneys, spleens and livers of fish, and the lowest bacterial load was found in 500 mg/kg LAM group. In vitro, LAM exerted a protective role against inactivated P. plecoglossicida-triggered inflammatory injury in primary head kidney macrophages (PKM) of large yellow croaker by recovering cell viability, suppressing NO production, and reversing pro-inflammatory cytokine expression (IL-1ß, IL-6, and IL-8). All these findings therefore will provide insights into the protection mechanism of LAM in fish, facilitating its application in prevention and control of fish bacteriosis.
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Enfermedades de los Peces , Perciformes , Animales , Antioxidantes/metabolismo , Pseudomonas , Proteínas de Peces/genética , Proteínas de Peces/metabolismoRESUMEN
OBJECTIVE: To investigate the association of polymorphisms in SEC16B rs633715, DNAJC27 rs713586, FTO rs11642015 and MC4R rs6567160 with overweight and obesity in Han Chinese preschool children. METHODS: A total of 749 Han Chinese preschool children from Henan and Guizhou Province of Long-term Health Effects Assessment Project of Infants and Toddlers Nutritional Pack were selected for the study and divided into an overweight and obese group and a normal control group in 2022. rs633715, rs713586, rs11642015 and rs6567160 were genotyped using Kompetitive allele-specific PCR(KASP) technology. The distribution of genotypic polymorphisms was compared using the χ~2 test. The association between the four loci and overweight and obesity in preschool children was analyzed using a multifactorial logistic regression model. RESULTS: The statistical analysis revealed a significant disparity(P<0.05) in the distribution of genotypic polymorphisms of rs633715 and rs6567160 among preschoolers in Henan and Guizhou Province. CC heterozygous mutant and recessive models at rs633715 locus were associated with susceptibility to overweight and obesity in preschool children [OR and 95% CI 2.915(1.163-7.305), and 2.997(1.226-7.323), respectively, both P<0.05]. TC heterozygous mutant and dominant models at rs713586 locus were also associated susceptibility to overweight and obesity in preschool children(OR and 95% CI were 2.362(1.054-5.289)and 2.362(1.054-5.289), respectively, both P<0.05). rs11642015 and rs6567160 loci were not associated with susceptibility to overweight and obesity in preschool children(P>0.05). The result of the analysis of the cumulative effect of rs633715 and rs713586 showed that the number of genotypes carrying the risk genotype was positively associated with the risk of overweight and obesity in preschool children(P_(trend)<0.01). CONCLUSION: Among Han Chinese preschool children, SEC16B rs633715 and DNAJC27 rs713586 were associated with susceptibility to overweight and obesity in preschool children. Moreover, rs633715 and rs713586 had a cumulative effect on susceptibility to overweight and obesity in preschool children, the number of risk genotypes carried was positively associated with childhood overweight and obesity risk.
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Dioxigenasa FTO Dependiente de Alfa-Cetoglutarato , Sobrepeso , Obesidad Infantil , Receptor de Melanocortina Tipo 4 , Preescolar , Humanos , Alelos , Dioxigenasa FTO Dependiente de Alfa-Cetoglutarato/genética , Predisposición Genética a la Enfermedad , Genotipo , Sobrepeso/genética , Obesidad Infantil/genética , Polimorfismo de Nucleótido Simple , Receptor de Melanocortina Tipo 4/genéticaRESUMEN
OBJECTIVE: To investigate the repairing effect of Lactobacillus acidophilus LA11-Only on ceftriaxone induced intestinal micronbiota imbalance in mice and its alleviating effect on lipid metabolism. METHODS: A total of 30 SPF BALB/c male mice were randomly divided into control group(10) and model group(20). The model group was given ceftriaxone sodium solution by gavage for a week to create a mouse model of antibiotic flora disorder. The natural recovery group(10) was given 10% skimmed milk solution by gavage, and the LA11-Onlly group was given Lactobacillus acidophilus skimmed milk solution(1.0×10~9CFU/mL). Two weeks later, the feces were collected aseptically.16S rRNA sequencing technology and ultra-high-performance liquid chromatography combined with mass spectrometry(UPLC-MS) were used to analyze the repair effect of LA11-Onlly on antibiotic induced bacterial flora disorder and lipid metabolism in mice. RESULTS: After ceftriaxone treatment, the diversity of intestinal microbiota in mice decreased, and there was a significant difference in the composition of flora compared with the control group; After treatment with LA11-Onlly, the Alpha diversity increased, the abundance of beneficial bacteria such as Lactobacillus and Butyricicoccus increased, and the composition of flora was closer to the control group; At the same time, the concentration of short chain fatty acids(SCFAs) increased in varying degrees. Compared with the natural recovery group, the levels of butyric acid and valeric acid in LA11-Onlly group increased significantly, close to the same level as the control group. CONCLUSION: Lactobacillus acidophilus LA11-Onlly probiotics can inhibit the growth of harmful bacteria by regulating the diversity and community composition of intestinal microbiota, promote the increase of the concentration of SCFAs, and alleviate the damage of antibiotics to the body.
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Lactobacillus acidophilus , Probióticos , Ratones , Masculino , Animales , Lactobacillus acidophilus/fisiología , Ceftriaxona/farmacología , Disbiosis , ARN Ribosómico 16S , Cromatografía Liquida , Espectrometría de Masas en Tándem , Probióticos/farmacología , Ácido Butírico , Antibacterianos/efectos adversos , Ratones Endogámicos C57BLRESUMEN
The increasing demand for fish consumption has promoted the rapid development of fish aquaculture. With the continuous expansion of culture scale and the deterioration of culture environment, various diseases have broken out frequently, leading to huge economic losses to fish farming. Antibiotics and chemicals are common options to prevent and control of fish diseases, but their use is now restricted or even banned due to serious problems such as drug residues, pathogen resistance, and environmental pollution. Herbs and their extracts have increasingly become promising supplements and alternatives, because of their effectiveness, safety, environmental friendliness and less drug resistance. The application of herbal medicines in prevention and control of fish diseases is mainly attributed to the powerful immune enhancement, antioxidation or direct anti-pathogenic efficacies of their effective components, including mainly polyphenols, polysaccharides, saponins, flavonoids, alkaloids, and essential oils. Recently these herbal active ingredients have been extensively studied for their efficacies in prevention and control of viral, bacterial, parasitic, and fungal diseases in fish. In the present paper, we comprehensively summarize the research progress of the active ingredients of herbal medicines used for prevention and control of fish diseases, especially of their action mechanisms, and highlight the potential application of the herbal medicines in fish aquaculture.
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Alcaloides , Medicamentos Herbarios Chinos , Enfermedades de los Peces , Plantas Medicinales , Animales , Acuicultura , Enfermedades de los Peces/prevención & control , PecesRESUMEN
The low efficiency of somatic cell nuclear transfer (SCNT) greatly limits its application. Compared with the fertilized embryo, cloned embryos display abnormal epigenetic modification and other inferior developmental properties. In this study, small RNAs were isolated, and miR-34c and miR-125b were quantified by real-time PCR; results showed that these micro-RNAs were highly expressed in sperm. The test sample was divided into three groups: one was the fertilized group, one was the SCNT control group (NT-C group), and the third group consisted of SCNT embryos injected with sperm-borne small RNA (NT-T group). The level of tri-methylation of lysine 9 on histone H3 (H3K9me3) at the 8-cell stage was determined by immunofluorescence staining, and the cleavage ratio, blastocyst ratio, apoptotic cell index of the blastocyst and total cell number of blastocysts in each group were analyzed. Results showed that the H3K9me3 level was significantly higher in the NT-C group than in the fertilized group and the NT-T group. The apoptosis index of blastocysts in the NT-C group was significantly higher than that in the fertilized group and the NT-T group. The total cell number of SCNT embryos was significantly lower than that of fertilized embryos, and injecting sperm-borne small RNAs could significantly increase the total cell number of SCNT blastocysts. Our study not only demonstrates that sperm-borne small RNAs have an important role in embryo development, but also provides a new strategy for improving the efficiency of SCNT in rabbit.
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MicroARNs , Técnicas de Transferencia Nuclear , Animales , Blastocisto , Clonación de Organismos , Desarrollo Embrionario/genética , Masculino , Conejos , EspermatozoidesRESUMEN
OBJECTIVE: To study the effect of calcium content on bone mineral density and intestinal microbiota in ovariectomized rats. METHODS: A total of 30 Wistar rats were randomly divided into 3 groups, namely the sham operation group, the model group and the calcium carbonate supplement group. Postmenopausal osteoporosis rats were established by ovariectomy(OVX). After the first week of modeling, each group was intragastric separately. The calcium carbonate solution was given to the calcium carbonate supplement group, and the same amount of sterile water was given to the other two groups. The animals were executed at the end of the 12 weeks. Left femur was taken and bone mineral density(BMD) was detected by dual-energy X-ray absorptiometry. The total DNA of fecal samples was aseptically extracted and the Illumina Miseq platform was to carry out high-throughput sequencing. RESULTS: Compared with the sham operation group, the body mass increment of rats in the model group was significantly increased, the level of BMD was significantly reduced(P<0. 05), the intestinal microbiota diversity was not significantly changed, the Firmicutes abundance was decreased, and the Bacteroidetes abundance was increased. Compared with the model group, the body mass increment of rats in the calcium carbonate supplementation group was significantly reduced and BMD was significantly increased(P<0. 05). There was no significant change in the intestinal microbiota diversity, Firmicutes were increased, and Bacteroidetes were decreased. CONCLUSION: Calcium supplementation can improve bone mineral density and inhibit the increase of body mass during the experiment period, and its mechanism may be related to regulating the structure of intestinal microbiota.
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Microbioma Gastrointestinal , Osteoporosis , Animales , Densidad Ósea , Calcio , Femenino , Humanos , Osteoporosis/prevención & control , Ovariectomía , Ratas , Ratas Sprague-Dawley , Ratas WistarRESUMEN
Aromatic and heterocyclic functionality are ubiquitous in pharmaceuticals. Herein, we disclose a new Mn(PDP)catalyst system using chloroacetic acid additive capable of chemoselectively oxidizing remote tertiary C(sp 3)-H bonds in the presence of a broad range of aromatic and heterocyclic moieties. Although catalyst loadings can be lowered to 0.1 mol% under a Mn(PDP)/acetic acid system for aromatic and non-basic nitrogen heterocycle substrates, the Mn(PDP)/chloroacetic acid system generally affords 10-15% higher isolated yields on these substrates and is uniquely effective for remote C(sp 3)-H hydroxylations in substrates housing basic nitrogen heterocycles. The demonstrated ability to perform Mn(PDP)/chloroacetic acid C(sp 3)-H oxidations in pharmaceutically relevant complex molecules on multi-gram scales will facilitate drug discovery processes via late-stage functionalization.
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OBJECTIVE: To establish an rat basophil leukemia(RBL)-2H3 cell line stably expressing human high affinity receptor containing alpha, beta and gamma chain(hFcεRIαßγ), in order to provide experimental materials for evaluating allergenicity of food. METHODS: The lentivirus was transfected into RBL-2H3 cells, and the mRNA expression of hFcεRIαßγ in cells was detected by real-time PCR and the protein expression of hFcεRIα was detected by flow cytometry. RESULTS: Sequencing result showed that recombinant lentiviral vector GV367-hFcεRIαßγ was successfully constructed. According to the result of experiments, lentivirus could effectively infect RBL-2H3 cells. The mRNA of hFcεRIαßγ and protein levels of hFcεRIα in RBL-2H3 cells were successfully overexpressed. CONCLUSION: The hFcεRIαßγ/RBL-2H3 cells were preliminarily constructed, which could be binded with human IgE and further used in the evaluation system of food allergy, compared to RBL-2H3 cells.
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Línea Celular , Hipersensibilidad a los Alimentos , Receptores de IgE/metabolismo , Animales , Humanos , Inmunoglobulina E , Ratas , Células Tumorales CultivadasRESUMEN
OBJECTIVE: To investigate the potential allergenicity of oryza sativa recombinant human serum albumin(OsrHSA)in BALB/c mice. METHODS: Eighty BALB/c mice were randomly divided into four groups i. e ovalbumin(OVA) positive control group, potato acid phosphatase(PAP) negative control group, Oryza sativa recombinant HAS(OsrHSA) group and solvent control group(phosphate buffer saline, PBS), respectively. Mice were administered by intraperitoneal injections of tested proteins and histamine levels in plasma and sIgE, sIgG, sIgG1, sIgG2 a, and tIgE antibody levels in serum were measured. RESULTS: Compared with the other groups, serum tIgE, sIgE, sIgG, sIgG1 and plasma histamine levels in the OVA group were significantly increased, while serum sIgG2 a levels were decreased(P<0. 05). There was no significant difference in serum sIgE level and histamine level between the OsrHSA group and the control group(P>0. 05). Serum sIgG, sIgG1 and sIgG2 a levels were lower than those in the PAP group(P<0. 05). There was no significant difference in serum tIgE content between PAP group and OsrHSA group(P>0. 05). CONCLUSION: The potential allergenicity of OsrHSA through traperitioneal injection in BALB/c mice was very low.
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Oryza , Alérgenos , Animales , Humanos , Ratones , Ratones Endogámicos BALB C , Ovalbúmina , Albúmina Sérica HumanaRESUMEN
OBJECTIVE: To evaluate the effects of genetically modified maize with Cry1Ab and epsps genes on immune function in F3 rats. METHODS: A total of 180 weaning SD rats for F0 generation were randomly divided into three groups, which were treated with AIN-93 G feed control diet, parental maize diet and genetically modified maize diet respectively. After three generations of breeding, antibody producing cells determination, concanavalin A(ConA)-induced lymphocyte transformation test, natural killer(NK)cells activities assay, whole blood lymphocyte subtype detection, delayed type hypersensitivity test and immunity organ index were performed. RESULTS: There were no significant differences between parental maize diet and genetically modified maize diet in terms of the number of antibody-producing cells, ConA-induced spleen lymphocyte proliferation, NK cell activity, whole blood lymphocyte subsets, delayed type hypersensitivity and thymus index(P>0. 05). CONCLUSION: Under the conditions of this experiment, no significant effects were found on immune function of F3 SD rats through the three generation development study of genetically modified maize with CrylAb and epsps genes.
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Alimentos Modificados Genéticamente , Zea mays/genética , Animales , Proteínas Bacterianas/genética , Endotoxinas , Proteínas Hemolisinas/genética , Plantas Modificadas Genéticamente , Ratas , Ratas Sprague-DawleyRESUMEN
The atomistic change of C( sp3)-H to C( sp3)-O can have a profound impact on the physical and biological properties of small molecules. Traditionally, chemical synthesis has relied on pre-existing functionality to install new functionality, and directed approaches to C-H oxidation are an extension of this logic. The impact of developing undirected C-H oxidation reactions with controlled site-selectivity is that scientists gain the ability to diversify complex structures at sites remote from existing functionality, without having to carry out individual de novo syntheses. This Perspective offers a historical view of why, as recently as 2007, it was thought that the differences between aliphatic C-H bonds of the same bond type (for example, 2° aliphatic) were not large enough to distinguish them preparatively with small-molecule catalysis in the absence of directing groups or molecular recognition elements. We give an account of the discovery of Fe(PDP)-catalyzed non-directed aliphatic C-H hydroxylations and how the electronic, steric, and stereoelectronic rules for predicting site-selectivity that emerged have affected a shift in how the chemical community views the reactivity among these bonds. The discovery that site-selectivity could be altered by tuning the catalyst [i.e., Fe(CF3-PDP)] with no changes to the substrate or reaction now gives scientists the ability to exert control on the site of oxidation on a range of functionally and topologically diverse compounds. Collectively, these findings have made possible the emerging area of late-stage C-H functionalizations for streamlining synthesis and derivatizing complex molecules.
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Bibliotecas de Moléculas Pequeñas/química , Catálisis , Compuestos Ferrosos/química , Hidroxilación , Estructura Molecular , Oxidación-Reducción , Bibliotecas de Moléculas Pequeñas/síntesis químicaRESUMEN
OBJECTIVE: To evaluate the neurotoxicity effects of the genetically modified maize with insect-resistant Cry1 Ab and herbicide-resistant epsps genes on the SD rats through three generation exposure. METHODS: 180 weaning SD rats for F0 generation were divided into three groups, which were treated with parental maize diet( YC group), genetically modified maize diet( T group) and AIN-93 G control diet( C group). After three generations of breeding, 20 litters of rats those from pre-weaning F3 generation were selected randomly to evaluate early postnatal developmental neurotoxicity. After weaning, 10 pups were randomly selected from each litter( 1 male or female per litter) for future experiments of motor activity, cognitive function and neuropathology assessment as adult. RESULTS: There were no statistically significant differences on early neurological development, neuroethology and cognitive ability. Only in the spatial probe test, the distance and time spent as well as their corresponding percentage in the target quadrant of YC group female rats were less compared with T group and C group( P < 0. 05). CONCLUSION: Under current experimental conditions, no adverse effects were found in neuroethology and cognitive ability on SD rats though the three generation study of genetically modified maize with Cry1Ab and epsps genes.
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Cognición/efectos de los fármacos , Plantas Modificadas Genéticamente , Zea mays/genética , Animales , Femenino , Masculino , Síndromes de Neurotoxicidad , Ratas , Ratas Sprague-Dawley , ReproducciónRESUMEN
Recent studies have demonstrated that neural precursor cell expressed, developmentally downregulated 9 (NEDD9) is highly expressed in various tumor tissues and cell lines. However, research on the role of NEDD9 in gastric cancer (GC) is rare, and the potential mechanism in tumor progression has not yet been explored. In this study, we investigated the role and mechanism of NEDD9 in GC. The expression of NEDD9 in GC tissues and cell lines was measured by immunohistochemistry, qRT-PCR, and Western blot, respectively. Inhibiting NEDD9 expression was carried out by siRNA transfection, and upregulating of NEDD9 was via NEDD9 overexpression plasmid. The ability of proliferation, migration, and invasion was detected by MTT assay, scratch wound assay, and transwell assay, respectively. The expression of vimentin, E-cadherin, Zeb1, and Zeb2 was measured by Western blot and qRT-PCR. We found that NEDD9 expression was dramatically increased both in GC tissues and cell lines, and the expression was significantly related to GC development. Knockdown of NEDD9 in SGC-7901 strongly inhibited its malignant capacity in vitro. Meanwhile, upregulation of NEDD9 in GES-1 increased the malignant capacity. In addition, the expression of vimentin, Zeb1, and Zeb2 was positively correlated with NEDD9, while E-cadherin was opposite. Collectively, our findings suggest that NEDD9 acts as an oncogene and promotes GC metastasis via EMT.
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Proteínas Adaptadoras Transductoras de Señales/biosíntesis , Movimiento Celular/genética , Proliferación Celular/genética , Fosfoproteínas/biosíntesis , Neoplasias Gástricas/genética , Proteínas Adaptadoras Transductoras de Señales/genética , Anciano , Apoptosis/genética , Cadherinas , Línea Celular Tumoral , Femenino , Regulación Neoplásica de la Expresión Génica , Humanos , Masculino , Persona de Mediana Edad , Invasividad Neoplásica/genética , Metástasis de la Neoplasia , Fosfoproteínas/genética , Neoplasias Gástricas/patologíaRESUMEN
At present, China's demand for high-speed railway construction is constantly increasing, and the construction of Multi line high-speed railway tunnels has been put on the agenda. The design and construction issues of super-large-sections tunnels urgently need to be addressed. The Xiabei mountain No. 1 and No. 2 tunnels in the Hangzhou-Taizhou Railway are typical shallow-buried super-large-section-tunnels in weak surrounding rock, and their design and construction issues are representative. Eleven monitoring sections were set up in the tunnel, including tunnel deformation, surrounding rock, shotcrete, steel frames, bolts and temporary support mechanical responses. Taking the monitoring data of the most typical cross-section as an example, the mechanical response of the support structure of a shallow-buried super-large-section tunnel was analyzed in detail. Based on previous research results, this paper discusses and summarizes the common construction problems of this type of tunnel, and puts forward corresponding suggestions. The existing formula for calculating surrounding rock pressure has poor applicability to super-large-section tunnels constructed by step excavation, resulting in conservative support parameters. Therefore, based on the monitoring values of surrounding rock pressure at 10 monitoring sections in Xiabei mountain No. 1 and No. 2 tunnels, empirical parameters reflecting the impact of step excavation were summarized. Based on the Wang formula and combined with the step excavation empirical parameters, an empirical formula for the surrounding rock pressure of shallow-buried super-large-section tunnels considering step excavation was constructed. The calculated results are in good agreement with the on-site monitoring data. This study can provide a good reference for similar projects.
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Understanding the characteristics and distribution patterns of the initial geo-stress field in tunnels is of great significance for studying the problem of large deformation of tunnels under high geo-stress conditions. This article proposes a ground stress field inversion method and large deformation level determination based on the GS-XGBoost algorithm and the Haba Snow Mountain Tunnel of the Lixiang Railway. Firstly, the hydraulic fracturing method is used to conduct on-site testing of tunnel ground stress and obtain tunnel ground stress data. Then, a three-dimensional model of the Haba Snow Mountain Tunnel will be established, and it will be combined with the GS-XGBoost regression algorithm model to obtain the optimal boundary conditions of the model. Finally, the optimal boundary condition parameters are substituted into the three-dimensional finite-difference calculation model for stress calculation, and the distribution of the in-situ stress field of the entire calculation model is obtained. Finally, the level of large deformation of the Haba Snow Mountain Tunnel will be determined. The results show that the ground stress of the tunnel increases with the increase of burial depth, with the maximum horizontal principal stress of 38.03 MPa and the minimum horizontal principal stress of 26.07 MPa. The Haba Snow Mountain Tunnel has large deformation problems of levels I, II, III, and IV. Level III and IV large deformations are generally accompanied by higher ground stress (above 28 MPa) and smaller surrounding rock strength. The distribution of surrounding rock strength along the tunnel axis shows a clear "W" shape, opposite to the surface elevation "M" shape. It is inferred that the mountain may be affected by geological structures on both sides of the north and south, causing more severe compression of the tunnel surrounding rock at the peak.
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Objective: The purpose of this study was to assess the safety of transgenic maize CC-2 through a 90-day feeding study in Sprague-Dawley rats. Methods: Transgenic maize CC-2 and its parental counterpart maize Zhengdan 958 were respectively incorporated into diets at levels of 70%, 35% or 17.5% (w/w) and were administrated to rats (n = 10/sex/group) for 90 days. An additional control group of rats (n = 10/sex/group) were fed with the AIN93 breeding diet. All formulated diets were nutritionally balanced. Results: There was no death and obvious toxic symptom in all rats. Food consumption, body weight, total food consumption rate, hematology, urinalysis, organ weight and organ coefficient were comparable between transgenic groups and the corresponding dose parental groups. There were significant differences of food consumption rate on some timepoint between high dose transgenic group and high dose parental group; male rats in high dose transgenic group showed significantly higher ALT/AST than high dose parental group on the middle or end of the experiment; but the differences showed no biological significance. There were no significant differences of other serum biochemistry parameters and pathological changes. Conclusion: The results in this study demonstrated that the transgenic maize CC-2 didn't cause any related toxicity in rats.
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Increasing evidence suggests that mitogen-activated protein kinase (MAPK) cascades play a crucial role in plant defense against viruses. However, the mechanisms that underlie the activation of MAPK cascades in response to viral infection remain unclear. In this study, we discovered that phosphatidic acid (PA) represents a major class of lipids that respond to Potato virus Y (PVY) at an early stage of infection. We identified NbPLDα1 (Nicotiana benthamiana phospholipase Dα1) as the key enzyme responsible for increased PA levels during PVY infection and found that it plays an antiviral role. 6K2 of PVY interacts with NbPLDα1, leading to elevated PA levels. In addition, NbPLDα1 and PA are recruited by 6K2 to membrane-bound viral replication complexes. On the other hand, 6K2 also induces activation of the MAPK pathway, dependent on its interaction with NbPLDα1 and the derived PA. PA binds to WIPK/SIPK/NTF4, prompting their phosphorylation of WRKY8. Notably, spraying with exogenous PA is sufficient to activate the MAPK pathway. Knockdown of the MEK2-WIPK/SIPK-WRKY8 cascade resulted in enhanced accumulation of PVY genomic RNA. 6K2 of Turnip mosaic virus and p33 of Tomato bushy stunt virus also interacted with NbPLDα1 and induced the activation of MAPK-mediated immunity. Loss of function of NbPLDα1 inhibited virus-induced activation of MAPK cascades and promoted viral RNA accumulation. Thus, activation of MAPK-mediated immunity by NbPLDα1-derived PA is a common strategy employed by hosts to counteract positive-strand RNA virus infection.
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Proteínas Quinasas Activadas por Mitógenos , Virus ARN Monocatenarios Positivos , Proteínas Quinasas Activadas por Mitógenos/genética , Proteínas Quinasas Activadas por Mitógenos/metabolismo , Virus ARN Monocatenarios Positivos/metabolismo , Ácidos Fosfatidicos , Sistema de Señalización de MAP Quinasas , FosforilaciónRESUMEN
Ceracris kiangsu Tsai (C. kiangs) is a kind of forest pest, which can harm nearly 100 kinds of weeds and crops. In this study, based on 314 species distribution points of C. kiangsu which were obtained from Chinese herbaria, literatures and investigation, and data of three future climate scenarios presented by CMIP6, two niche models (Garp, Maxent) were used to predict the suitable area of C. kiangsu in China. The result shows that the main environmental factors affecting the distribution of C. kiangsu are precipitation of driest month (bio14) and min temperature of coldest month (bio6). No matter now and future, the potential distribution areas of C. kiangsu in China are mainly in the south of Qinling-Huaihe River. Under current scenarios, the areas of the total, highly, moderately and poorly suitable of C. kiangsu in China are 160.65 × 104 km2, 31.70 × 104 km2, 60.36 × 104 km2 and 68.59 × 104 km2 respectively. The southern Hubei, western Jiangxi and eastern Hunan are highly-suitable areas. Under SSP1-2.6 and SSP2-4.5 scenarios, both the total suitable area and the highly suitable show a decreasing tread in 2050s. Compared to the 2050s, the total suitable area will coninue to decease in 2090s under SSP1-2.6, while it will increase under SSP2-4.5. The highly suitable area will increase in both scenarios, and the increased percentage under SSP2-4.5 is greater than that under SSP1-2.6. Under SSP5-8.5 scenarios, the total suitable area will increase by 1.83% in the 2050s, and decrease by 1.17% in the 2090s. The highly suitable area in the 2050s and 2090s under this scenarios is larger than under current scenarios. No matter what the scenario, the southern part of Yunnan, the southeast of Sichuan and the southwest of Chongqing will become highly-suitable areas as the climate continues to warm and should be monitored more cosely.