38 research outputs found

    Identifying Expressway Accident Black Spots Based on the Secondary Division of Road Units

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    For the purpose of reducing the harm of expressway traffic accidents and improving the accuracy of traffic accident black spots identification, this paper proposes a method for black spots identification of expressway accidents based on road unit secondary division and empirical Bayes method. Based on the modelling ideas of expressway accident prediction models in HSM (Highway Safety Manual), an expressway accident prediction model is established as a prior distribution and combined with empirical Bayes method safety estimation to obtain a Bayes posterior estimate. The posterior estimated value is substituted into the quality control method to obtain the black spots identification threshold. Finally, combining the Xi\u27an-Baoji expressway related data and using the method proposed in this paper, a case study of Xibao Expressway is carried out, and sections 9, 19, and 25 of Xibao Expressway are identified as black spots. The results show that the method of secondary segmentation based on dynamic clustering can objectively describe the concentration and dispersion of accident spots on the expressway, and the proposed black point recognition method based on empirical Bayes method can accurately identify accident black spots. The research results of this paper can provide a basis for decision-making of expressway management departments, take targeted safety improvement measures

    The Effect on Long-Chain Fatty Acids in Lucerne Silage with Jujube Powder and \u3cem\u3eLactobacillus plantarum\u3c/em\u3e

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    The major nutrients of lucerne silage are well documented. However, forages are also an important dietary source of α-linolenic acid (C18:3n-3) and linoleicacid (C18:2n-6) that are biohydrogenated in the rumen, originating a complex pattern of C18 fatty acids (Jenkins et al. 2008). Studies have reported slight effects on the fatty acid (FA) composition of grass silages by the use of additives like formalin, formic acid, or enzymes (Alves et al. 2011) However, there are no studies on the addition of jujube powder in lucerne silage, which has a high sugar content. The effect of Lactobacillus plantarum (LA) on the silage fermentation quality has been frequently observed. Few studies have focussed on long-chain fatty acids in lucerne silage with jujube powder and Lactobacillus plantarum. The objective of this study was to evaluate the effect of the addition of jujube powder and the Lactobacillus plantarum on the long-chain fatty acids (mainly C16-C18) in lucerne silage

    A Lactic Acid Bacterium Isolated from Grass in Native Grassland in Northern China

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    The epiphytic LAB converts sugar into lactic acid during the ensiling process. As a result, the pH is reduced, and the forage is preserved. Therefore, further study of epiphytic LAB species is required, especially the screening of excellent LAB. However, to our knowledge, limited information is available on the epiphytic microflora on grass in native grassland. The present study set out to screen, isolate and identify the LAB from grass silages made in native grass-land in northern China

    5-HT1A Receptor Agonist Promotes Retinal Ganglion Cell Function by Inhibiting OFF-Type Presynaptic Glutamatergic Activity in a Chronic Glaucoma Model

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    Serotonin receptors are potential neuroprotective agents in degenerative diseases of the central nervous system. The protective effects of serotonin receptor (5-HT1A) agonists on the survival and function of retinal ganglion cells (RGCs) by regulating the release of the presynaptic neurotransmitter Îł-aminobutyric acid (GABA) were confirmed in our previous study of a chronic glaucoma rat model. However, the roles of excitatory amino acids and their interactions with the 5-HT1A receptor in glaucoma remain unknown. Here, we found that ocular hypertension increased glutamine synthetase (GS) and excitatory amino acid transporter 2 (EAAT2) expression in rat retinas. In addition, the high expression of GS and EAAT2 induced by glaucoma was downregulated by the 5-HT1A receptor agonist 8-OH-DPAT and the 5-HT1A receptor antagonist WAY-100635, respectively. Patch-clamp techniques were used to record glutamate receptor-mediated spontaneous and miniature glutamatergic excitatory post-synaptic currents (sEPSCs and mEPSCs) as well as L-glutamate-induced current in OFF-type and ON-type RGCs in rat retinal slices. Although there were no significant differences in the frequency and amplitude of sEPSC and mEPSC release between normal and glaucoma OFF- and ON-type RGCs, exogenous 8-OH-DPAT administration specifically reduced the frequency, but not the amplitude, of sEPSC and mEPSC release in glaucoma OFF-type rather than ON-type RGCs; these effects were completely blocked by WAY-100635. In summary, 8-OH-DPAT decreases and increases GS and EAAT2 expression of glaucomatous retina, respectively, while decreasing sEPSC and mEPSC frequency. In contrast, WAY-100635 increases and decreases GS and EAAT2 expression of glaucomatous retina, respectively, while increasing sEPSC and mEPSC frequency. The reduction of glutamatergic presynaptic transmission by 8-OH-DPAT deactivates RGCs at the neural network level and reduces the excitotoxic damage in the pathological process of chronic glaucoma

    Effect of \u3cem\u3eLactobacillus plantarum\u3c/em\u3e on Fermentation Quality of Alfalfa Silages Mixed with Different Proportions of Jujube Powder

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    Hebei province is one of the main production areas of alfalfa (Medicago sativa) in China. While alfalfa is used to make silages, it is necessary to improve the fermentation quality of alfalfa silage. Jujube powder which contains a high content of sugar, might be a good material to ensile mixed with alfalfa. On the other hand, the effect of lactic acid bacteria (LAB) has been documented and has been used as an additive to achieve good preservation of silage. The objective of this study was a) to screen different ratios of jujube powder in the mixed silage of alfalfa and jujube powder and b) verify the effect of Lactobacillus plantarum strain on fermentation quality of the alfalfa silages

    Rapid evaluation of earthquake-induced landslides by PGA and Arias intensity model: insights from the Luding Ms6.8 earthquake, Tibetan Plateau

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    On September 5, 2022, a magnitude 6.8 earthquake occurred along the Xianshuihe Fault Zone in Luding County, Tibetan Plateau, China, leading to a significant outbreak of landslides. The urgent need for a swift and accurate evaluation of earthquake-induced landslides distribution in the affected area prompted this study. This research delves into regional geological data, scrutinizes post-earthquake Peak Ground Acceleration (PGA) and Arias Intensity (Ia) associated with the Luding earthquake, and conducts earthquake-induced landslides risk assessments within the Luding earthquake zone using the Newmark model. Validation of the earthquake-induced landslides risk assessment outcomes rooted in PGA and Ia relies on an earthquake-induced landslides database, revealing Area Under the Curve (AUC) values of 0.73 and 0.84 in respective ROC (Receiver Operating Characteristic) curves. These results unequivocally affirm the exceptional accuracy of earthquake-induced landslides evaluation using Ia calculations, emphasizing its suitability for the swift prediction and evaluation of earthquake-induced landslides. The earthquake-induced landslides risk assessment based on Ia computation reveals the area with extremely high-risk and high-risk of earthquake-induced landslides encompass 0.71% of the entire study area. Notably, these areas are predominantly clustered within seismic intensity VII zones and primarily trace the Moxi fault zone, extending from the southern portion of the middle east along the Dadu River and the Moxi fault, with reach up to Dewei Township in the north and Caoke Township in the south. Hazard-prone regions predominantly align with slopes featuring gradients of 30°–45° and bear a strong correlation with fault activity. Furthermore, the results of this evaluation are harmonious with the findings from remote sensing interpretation and on-site field investigations pertaining to the earthquake-induced landslides. This body of knowledge can serve as a crucial reference for expedited assessment, emergency response and subsequent supplementation of earthquake-induced landslide databases when confronting similar earthquake-induced landslide scenarios

    Application fruit tree hole storage brick fertilizer is beneficial to increase the nitrogen utilization of grape under subsurface drip irrigation

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    It is very important to promote plant growth and decrease the nitrogen leaching in soil, to improve nitrogen (N) utilization efficiency. In this experiment, we designed a new fertilization strategy, fruit tree hole storage brick (FTHSB) application under subsurface drip irrigation, to characterise the effects of FTHSB addition on N absorption and utilization in grapes. Three treatments were set in this study, including subsurface drip irrigation (CK) control, fruit tree hole storage brick A (T1) treatment, and fruit tree hole storage brick B (T2) treatment. Results showed that the pore number and size of FTHSB A were significantly higher than FTHSB B. Compared with CK, T1 and T2 treatments significantly increased the biomass of different organs of grape, N utilization and 15N content in the roots, stems and leaves, along with more prominent promotion at T1 treatment. When the soil depth was 15–30 cm, the FTHSB application significantly increased the soil 15N content. But when the soil depth was 30–45 cm, it reduced the soil 15N content greatly. T1 and T2 treatments obviously increased the activities of nitrite reductase (NR) and glutamine synthetase (GS) in grape leaves, also the urease activity(UR) in 30 cm of soil. Our findings suggest that FTHSB promoted plant N utilization by reducing N loss in soil and increasing the enzyme activity related to nitrogen metabolism. In addition, this study showed that FTHSB A application was more effective than FTHSB B in improving nitrogen utilization in grapes

    Flexible thermoelectric generator with high Seebeck coefficients made from polymer composites and heat-sink fabrics

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    Light and flexible thermoelectric generators working around room temperature and within a small temperature range are much desirable for numerous applications of wearable microelectronics, internet of things, and waste heat recovery. Herein, we report a high performance flexible thermoelectric generator made of polymeric thermoelectric composites and heat sink fabrics. The thermoelectric composites comprise n- and p-type Bi2Te3 particles and poly(3,4-ethylenedioxythiophene) polystyrene sulfonate, exhibiting a synergic effect that results in Seebeck coefficients higher than those of the constituent alloys and conductive polymer. The flexible and light thermoelectric generator produces an output power of 9.0 mW, a specific output power of 2.3 mW/g, and an areal power density of 6.5 W/m2 at ΔT = 45 K. By using the heat sink fabrics to maintain a large and uniform distribution of temperature difference across the generator, a three-fold increment of the output power is obtained

    Effect of diosmetin on young rats with high-fat diet-induced non-alcoholic fatty liver disease

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    Purpose: To determine the effect of diosmetin on young, non-alcoholic fatty liver disease (NAFLD) rats. Methods: Five groups of SD rats were used: control group, high-fat diet group, low-dose diosmetin group, medium-dose diosmetin group, and high-dose diosmetin group, each with 10 rats. After 3 months, interleukin 6 (IL-6), IL-1β) and TNF-α) were assayed. Protein expressions of p-AMPKα, CPT-1 and PPAR-α, AMPKα, SREBP-1c and FAS were assayed. Results: In the high-fat diet group, the levels of p-AMPKα, CPT-1 and PPAR-α were lower than the corresponding control values, while p-AMPKα, CPT-1 and PPAR-α levels were dose-dependently higher in all diosmetin groups than in NAFLD group (p < 0.05). There were higher levels of SREBP-1c and FAS in the high-fat diet group than in control group, while SREBP-1c and FAS levels in all diosmetin groups were dose-dependently lower than the corresponding levels in NAFLD group. Serum IL-6, IL-1β and TNF-α levels in NAFLD group were raised, relative to control values (p < 0.05). Conclusion: Diosmetin alleviates NAFLD lesions induced by high-fat diet, slows down liver cell apoptosis, and inhibits inflammation via activation of AMPK pathway. Thus, diosmetin has potentials for use in the repair of hepatic damage induced by high-fat diet

    Analysis of spatial variability and influencing factors of arsenic in groundwater of Hetao Plain, Inner Mongolia

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    Hetao Plain is one of the most serious area of local arsenic poisoning in China.Based on shallow groundwater arsenic samples, the paper used the semivariogram to reveal the spatial distribution and heterogeneity of groundwater arsenic concentration, and further discussed the influencing factors.The results show that the arsenic concentration in groundwater generally increases from south to north in the Hetao Plain.The residual groundwater arsenic concentration is fitted to the pure nugget effect model under the assumption of isotropic conditions, which means it is random on the measured scale, so there is no spatial autocorrelation and the variance is great in short distances.The fractal dimension value is large(D=1.999), further indicating the distinct variation of groundwater arsenic concentration within the measured scale.Groundwater arsenic is closely related to organic matters in sediments.Since the Late Quaternary, the tectonic movements of the northern mountains and changes in the sedimentary environment of the basin has caused multiple sedimentary facies, resulting in a high degree of spatial variability in burial conditions of organic matters.The high spatial variability of organic matters characteristics further leads to high spatial variability of groundwater arsenic concentration.The slow groundwater flow plays an important role in maintaining this pattern.This article focuses on the spatial heterogeneity of groundwater arsenic in the Hetao area, which has scientific significance for effectively predicting the potential risk of arsenic exposure in drinking water in unknown areas, accurately preventing endemic diseases and ensuring water supply safety
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