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In order to analyze the influence of the uncertainty of hydrogeological parameters on the output of the groundwater numerical simulation model, this paper studies a hypothetical example. First, a groundwater numerical simulation model is established. Then sensitivity analysis is used to screen out the parameters that have a greater impact on the output of the simulation model. As a random variable, in order to reduce the computational load caused by repeatedly calling the simulation model, the Kriging method and the BP neural network method are used to establish the replacement model of the simulation model and the accuracy levels of the two are compared, and the BP neural network replacement model with higher accuracy is selected to perform Monte Carlo simulation. Among them, when the BP neural network method is used to establish the replacement model, the third-point algorithm is used to quickly determine the number of hidden layer nodes that minimize the error of the replacement model. Finally, the results of the random simulation are statistically analyzed and the interval estimation and evaluation of the risk of groundwater pollution are compared. The results show that when the confidence level is 90%, the confidence intervals for the concentration of the three observation wells are 367.48~415.67, 205.12~230.33 and 118.85~132.82 mg/L. Combined with the risk assessment, it is calculated that the risk of groundwater pollution in observation wells No.1, No.2 and No.3 in the study area are 0.66, 0.60, and 0.58, which provides a scientific basis for groundwater pollution prevention and control. [ABSTRACT FROM AUTHOR]

Six kinds of cosmetics, including cleanser, care cosmetics and makeup categories, and seven representative microorganisms were selected to conduct the partial equivalence study between amplified ATP bioluminescence assay and the detection method of aerobic bacterial count and molds and yeast count in Safety and Technical Standard for Cosmetics (2015th Edition). The seven representative microorganisms were inoculated into the six kinds of cosmetics at target concentrations of 10, 5, 1 and 0.1 CFU/g, respectively. Tests on each concentration were repeated five times. Fisher exact test statistical analysis show that the detection limit of amplified ATP bioluminescence assay is significantly better than that of the standard method (p=0.000 1). Seven representative strains grew well in the MTAT medium, and the results of artificially contaminated samples detected by the amplified ATP bioluminescence assay were all positive, indicating that the method has good specificity. Three different laboratories were selected to compare the two methods using the same samples, and no statistical difference was found in the results, indicating the method is reproducible (p>0.05). The enrichment media MTAT, prepared with selected brands of TAT base medium, were assessed using growth promotion, and their ATP test results were all positive, indicating that the method is has good durability. Therefore, the amplified ATP bioluminescence assay is partially equivalent to the standard method. [ABSTRACT FROM AUTHOR]

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A method of designing cathode in electrochemical machining by numerical simulation was proposed based on the analysis of problems existed in traditional design methods. The course of designing cathode and the method of determining the initial cathode shape by simulation were given. The mathematical model for ECM was established, the finite element method was used to calculate the electrical field and flow field. Then a set of tool software for designing cathode was developed and applied to the practice. Results demonstrate that the proposed method can effectively improve the design accuracy, reduce the number of trial and error cycles and shorten the periods of cathode design. [ABSTRACT FROM AUTHOR]

Objective: To explore the effect of cytokine levels on early death and coagulation function of patients with newly diagnosed acute promyelocytic leukemia (APL)., Methods: Routine examination was performed on 69 newly diagnosed APL patients at admission. Meanwhile, 4 ml fasting venous blood was extracted from the patients. And then the supernatant was taken after centrifugation. The concentrations of cytokines, lactate dehydrogenase (LDH) and ferritin were detected by using the corresponding kits., Results: It was confirmed that cerebral hemorrhage was a major cause of early death in APL patients. Elevated LDH, decreased platelets (PLT) count and prolonged prothrombin time (PT) were high risk factors for early death ( P <0.05). The increases of IL-5, IL-6, IL-10, IL-12p70 and IL-17A were closely related to the early death of newly diagnosed APL patients, and the increases of IL-5 and IL-17A also induced coagulation disorder in APL patients by prolonging PT ( P <0.05). In newly diagnosed APL patients, ferritin and LDH showed a positive effect on the expression of IL-5, IL-10 and IL-17A, especially ferritin had a highly positive correlation with IL-5 ( r =0.867) and IL-17A ( r =0.841). Moreover, there was a certain correlation between these five high-risk cytokines, among which IL-5 and IL-17A ( r =0.827), IL-6 and IL-10 ( r =0.823) were highly positively correlated., Conclusion: Elevated cytokine levels in newly diagnosed APL patients increase the risk of early bleeding and death. In addition to the interaction between cytokines themselves, ferritin and LDH positively affect the expression of cytokines, thus affecting the prognosis of APL patients.

The Three-River Headwaters region is a hotspot for studying the response of soil function to climate change. To study the horizontal variation characteristics of alpine grassland soil function and vertical changes along soil genetic horizons, soil functional indicators (including respiration, nitrogen conversion rate, and enzymatic activity) of different genetic horizons in alpine grassland soil profiles and their correlations with environmental factors were analyzed. The results showed that there were no significant differences in soil functional characteristics between alpine meadows and steppes, and topsoil had higher respiration rates, nitrogen conversion rates, and enzymatic activities than those of subsoil. Total nitrogen was a key driver of soil functional characteristics in different genetic horizons, explaining 18.3%, 21.4%, and 27.5% of the horizontal variation in functional characteristics, respectively. Climate and vegetation factors mainly affected soil function indirectly by changing soil physicochemical properties in topsoil, but atmospheric nitrogen deposition still affected soil function in subsoil. These results indicate the significant nitrogen limitation of alpine grassland soil in the Three-River Headwaters region, and the findings provide a new insight into the maintenance of soil functional diversity and the response to climate change in the context of global climate change.

Soil respiration and extracellular enzyme activity are important components of the material cycle of mountain ecosystems and play key roles in maintaining ecosystem functions. To explore the coupling relationship between soil functions and environmental factors, the soil functional indicators, environmental factors, and effects of altitude on the soil function of 36 soil samples from 12 altitudes of the Meili Mountain were analyzed. The results showed that there were significant differences in soil respirations and enzyme activities among altitudes of Meili Mountain, and high-altitude areas had higher soil functions. Soil functions increased with altitudinal difference. PCA analysis showed that the first three axes explained 56.7%, 17.4%, and 8.7% of the variance in soil functional elevation change, respectively, indicating that the functional changes related to carbon and phosphorus were higher than those related to nitrogen. There were significant correlations between environmental factors and soil functional indicators; soil function indicators had stronger correlations with soil physicochemical properties than with climatic factors. Altitude mainly affected soil function indirectly by affecting soil physicochemical properties and climatic factors. These results have great scientific significance for improving the understanding of the material cycle and ecological function of the Meili Mountain ecosystem and provide an important reference for in-depth study of the altitude distribution pattern and evolution characteristics of the soil function of the mountain ecosystem.

Objective: To compare the efficacy of dextraldexmede (DEX) and propofol on sedation and β-endorphin (β-EP) in patients with moderate and severe traumatic brain injury (TBI)., Methods: Ninety patients with moderate and severe TBI with Glasgow coma score (GCS) 6-13 were randomly divided into three groups according to the order of admission of odd and even numbers. In group A (DEX/+morphine), DEX load 0.5-1.0 μg/kg was injected within 30 minutes, and maintaining at 0.2-0.6 μg×kg⁻¹ × h⁻¹ for 24 hours; and in group B (propofol/+ morphine), propofol load 0.5-2.0 mg/kg was injected within 10 minutes, and maintaining at 1-3 mg×kg⁻¹×h⁻¹ for 72 hours. Patients with poor efficacy were added with morphine intravenously. In group C, intramuscular injection of pethidine and other temporary medication was injected. The comprehensive assessment was conducted according to the Riker sedation and agitation score, combined with the physiological body reaction positive indicator elimination. The vital signs was monitored, and blood white blood cell (WBC) count, blood sugar, cortisol and β-EP before and after administration were determined., Results: (1) The sedation efficiency rate of the group A, B, C were 84.38% (27/32), 80.64% (25/31), 77.78% (21/27), respectively. The booster dose of morphine in group A was less than that in group B (24 h dosage: 16.23 ± 3.45 mg vs. 21.34 ± 5.55 mg). (2) Blood pressure and heart rate were significantly affected in the group A. The mean arterial pressure (MAP) in 0.5 hour of reaching loading dose in group A was significantly lower than that in group B and C (75.50 ± 9.35 mm Hg vs. 87.90 ± 8.05 mm Hg, 85.70 ± 7.10 mm Hg, both P<0.05). (3) WBC and cortisol levels showed downwards trends after treatment in group A and group B; WBC fell more in the group A compared with group B, cortisol level fell more in group B compared with group A, and the WBC and cortisol level began to decline after 24 hours in group C. (4) There were no significant differences in blood sugar and β-EP levels before and after treatment in group B, but β-EP had an increasing tendency in group A and group C, and the amplification in group C was more obvious than that in group A., Conclusions: The sedation efficacy of DEX was superior to propofol in moderate and severe TBI, and was able to control excessive stress response after TBI better, and with more effect on blood pressure. Plasma β-EP was elevated during the early phase of brain injury by DEX, which was considered as its positive role in the regulation of early stress.

Effects of bromide and ferric ions on the formation and distribution of tri-halomethanes (THMs) have been investigated. As disinfection by-product (DBP) model precursors of natural water, humic acid solutions were used and a series of experiments were conducted. The results showed that bromide in this reaction system not only contributed to the increase of brominated species, but also the total tri-halomethanes. When the concentration of Br(-) was 1.0 mg/L, the total amount of produced THMs reached to 270% of that without bromide ions. In the presence of bromide, ferric ions decreased the production of THMs at pH 6, but increased the production of THMs at pH 8, especially for the amount of tri-bromomethanes. When the concentration of Fe3+ was 5 mg/L, the amount of produced tri-bromomethanes had an increment of 54% (from 51.7 microg/L to 79.4 microg/L), and the total amount of THMs increased from 113.49 microg/L to 162.09 microg/L. Bromide ions had a significant effect on carcinogenicity risk in disinfection of drinking water by chlorine, and the co-existence of ferric ion and bromide in alkalescent environment can result in the biggest challenge on carcinogenicity risk. Under the condition of 0.2 mg/L Br(-), 5 mg/L Fe3+ and pH 6, the carcinogenicity risk increased 2.5 times than that without Br(-) and Fe3+, and much higher increment of 5.1 times appeared when pH was 8.

Objective: To study the dynamic changes of platelet number in early multiple injured patients and its clinical significance., Methods: Ninety patients with multiple injury less than 48 hours were selected. Blood analysis was dynamicly investigated at 1, 24, 72, 120 and 168 hours after in Hospital, and acute physiology and chronic health evaluation III (APACHE III) and injury seriousness scale (ISS) scores were recorded., Results: The platelet number declined after injury, reached the lowest point at 72 hours after in hospital, then restored to the normal level at 120 hours. In the platelet decrease group, the trauma was more critically[ISS (29.60+/-9.80) scores vs. (22.30+/-12.00) scores, (P<0.05)] and the incidence of multiple organs dysfunction syndrome (MODS) was higher than normal group (83.9% vs. 62.7%, P<0.05). In the death group, the number of platelet was declined[ (30.1+/-10.3) hours vs. (51.3+/-14.8) hours, (P<0.05) and the lasting tine was longer[ (63.7+/-11.0) hours vs. (54.2+/-13.4) hours, (P<0.05)., Conclusion: The platelet number declines after multiple injury. The decrease and continuously lower level of platelet suggest poor prognosis.