Determination of Total Flavonoids in Acanthopanax senticosus(Rupr. et Maxim.) Harms by Enzymolysis and Its Technological Optimization

In order to optimize the ultrasonic extraction technique for the total flavonoid of leaf yellows plus, the contents of 21 leaf yellows plus total flavonoid from four regions in Heilongjiang Province were comparatively analyzed. The ultrasonic extraction technology was optimized by Box-Behnken response surface method, and the total flavonoid content of 21 kinds of Acanthopanax senticosus(Rupr. et Maxim.) Harms from different producing areas were analyzed by cluster analysis. The optimal process conditions were determined as ultrasonic time 30 min, solid-liquid ratio 1 : 12 and ultrasonic power 250 W, and the average yield of the total flavonoid was 1.453 mg·g^ (-1). By optimizing the ultrasonic-assisted extraction method, the total flavonoid content from different producing areas was compared in the experiment, which provided certain data support for the optimization of the extraction process in the future and laid a certain theoretical foundation for the quality analysis of Chinese medicinal materials.

Determination of total selenium in geological samples by HG-AFS after concentration with thiol cotton fiber

Standard reference material and different geological samples were dissolved by system A (the mixture of nitric and perchloric acids) and system B (mixture of nitric, perchloric and hydrofluoric acids), and total Se in all samples was measured by hydride-generation atomic fluorescence spectrometry (HG-AFS) after concentration with thiol cotton fiber (TCF). The analytical results obtained by the two digestion method are in good agreement (within the limit of errors) for most of the samples, particularly for those having recommended values. The Se concentrations determined by the two methods are of no difference, and the correlation coefficient is 0.9986; the relative standard deviation (RSD) for the determination of 0.04 μg/g Se is 10.2%. The recovery rates of systems A and B by the stan- dard-addition method were 96%–106% and 99%–104%, respectively.

Effects of Conservation Methods of Water Samples on Determination of Total Phosphorus

Effects of conservation methods of water samples on determination of total phosphorus were analyzed from aspects of methods of adding conserving agent, SS concentration, natural sedimentation time, conservation temperature and time. The results showed that SS concentration in water and natural sedimentation time had the greatest impact on the determination of total phosphorus, while the influence of methods of adding conserving agent, conservation temperature and time was relatively smaller. TP concentration in water samples conserved irregularly was higher than the standard value due to the existence of SS and microorganisms in water, and the deviation became larger with the increase of SS concentration in water. In addition, quality control measures and matters needing attention during the conservation process of water samples were put forward to improve the accuracy of TP concentration.

Test and Research of Total Quantity of N and P Fertilizers for Maize

Objective] The alm was to provide scientific references for determination of optimal N and P quantities of malze. [Method] The research conducted a test in field to expIore the effects of N and P fertiIizers on malze yield. [Result] Both of N and P fertiIizers have significant effects on malze yield. When malze yield reached the highest, the quantities of N fertiIizers and P fertiIizers were 530.56 and 105.44 kg/hm2, respectiveIy. [Conclusion] Malze yield keeps growing upon N or P fertiIizers to certaln extent, and excessive quantities of N and P fertiIizer wouId reduce malze yield.

Total Amount Control Test of Nitrogen Fertilizer and Phosphate Fertilizer on Winter Wheat

[Objective] This study was conducted to optimize the suitable application amounts of nitrogen fertilizer and phosphate fertilizer for winter wheat.[Method] A field experiment was carried out to investigate the effects of the application amounts of nitrogen fertilizer and phosphate fertilizer on the yield of winter wheat.[Result]The quadratic simulation function between the application of nitrogen fertilizer and wheat yield was y =-0.6611x^2＋20.091 x ＋234.85,with a correlation coefficient of0.970 8,and the yield of winter wheat was the highest at the application amount of nitrogen fertilizer of 228.0 kg/hm^2.The quadratic simulation function between the application of phosphate fertilizer and wheat yield was y =-0.572 6x^2＋13.168 x ＋340.4,with a correlation coefficient of 0.921 95,and the yield of winter wheat was the highest at the application amount of phosphate fertilizer of 172.5 kg/hm^2.[Conclusion] This study provides a scientific basis for the rational application of nitrogen fertilizer and phosphate fertilizer on winter wheat.

Designing Adaptive Multiple Dependent State Sampling Plan for Accelerated Life Tests

A novel adaptive multiple dependent state sampling plan(AMDSSP)was designed to inspect products from a continuous manufacturing process under the accelerated life test(ALT)using both double sampling plan(DSP)and multiple dependent state sampling plan(MDSSP)concepts.Under accelerated conditions,the lifetime of a product follows the Weibull distribution with a known shape parameter,while the scale parameter can be determined using the acceleration factor(AF).The Arrhenius model is used to estimate AF when the damaging process is temperature-sensitive.An economic design of the proposed sampling plan was also considered for the ALT.A genetic algorithm with nonlinear optimization was used to estimate optimal plan parameters to minimize the average sample number(ASN)and total cost of inspection(TC)under both producer’s and consumer’s risks.Numerical results are presented to support the AMDSSP for the ALT,while performance comparisons between the AMDSSP,the MDSSP and a single sampling plan(SSP)for the ALT are discussed.Results indicated that the AMDSSP was more flexible and efficient for ASN and TC than the MDSSP and SSP plans under accelerated conditions.The AMDSSP also had a higher operating characteristic(OC)curve than both the existing sampling plans.Two real datasets of electronic devices for the ALT at high temperatures demonstrated the practicality and usefulness of the proposed sampling plan.

Test Studies on Performances of TGP Total Gradation Concrete

The Three Gorges Project (TGP) is the largest water conservancy and hydropower complex in the world, with a concrete consumption of 28 million m^3 in total. For such a significant world-attracting project, first rate quality concrete is needed. Various mechanical and deformation performances of hydraulic mass concrete are determined conventionally by the wet screening method to make small specimens and the test results of the small standard specimens are taken to represent the properties of the mass concrete. However, the quantity of the coarse aggregate after wet screening would be reduced by 30% or so and the gel materials would increase by 20% or so, thus causing significant differences between the properties of the small concrete specimen and that of the total gradation concrete. To well understand the performances of the total gradation concrete of TGP dam, test studies have been performed on the total gradation concrete, including compressive strength, split tensile strength, elastic modulus, ultimate tension, dry shrinkage, self volume deformation, creep, seepage prevention, and so on, and comparison made with the small standard specimens to find out the relationship between them, which have provided scientific ground for the design, operation and safety verification of the TGP dam.

Total pollution effect of urban surface runoff

For pollution research with regard to urban surface runoff, most sampling strategies to date have focused on differences in land usage. With single land-use sampling, total surface runoff pollution effect cannot be evaluated unless every land usage spot is monitored. Through a new sampling strategy known as mixed stormwater sampling for a street community at discharge outlet adjacent to river, this study assessed the total urban surface runoff pollution effect caused by a variety of land uses and the pollutants washed off from the rain pipe system in the Futian River watershed in Shenzhen City of China. The water quality monitoring indices were COD （chemical oxygen demand）, TSS （total suspend solid）, TP （total phosphorus）, TN （total nitrogen） and BOD （biochemical oxygen demand）. The sums of total pollution loads discharged into the river for the four indices of COD, TSS, TN, and TP over all seven rainfall events were very different. The mathematical model for simulating total pollution loads was established from discharge outlet mixed stormwater sampling of total pollution loads on the basis of four parameters： rainfall intensity, total land area, impervious land area, and pervious land area. In order to treat surface runoff pollution, the values of MFF30 （mass first flush ratio） and FF30 （first 30% of runoff volume） can be considered as split-flow control criteria to obtain more effective and economical design of structural BMPs （best management practices） facilities.

National trends in total hip arthroplasty for traumatic hip fractures:An analysis of a nationwide all-payer database

BACKGROUND Hemiarthroplasty(HA)has traditionally been the treatment of choice for elderly patients with displaced femoral neck fractures.Ideal treatment for younger,ambulatory patients is not as clear.Total hip arthroplasty(THA)has been increasingly utilized in this population however the factors associated with undergoing HA or THA have not been fully elucidated.AIM To examine what patient characteristics are associated with undergoing THA or HA.To determine if outcomes differ between the groups.METHODS We queried the Nationwide Inpatient Sample(NIS)for patients that underwent HA or THA for a femoral neck fracture between 2005 and 2014.The NIS comprises a large representative sample of inpatient hospitalizations in the United States.International Classifications of Disease,Ninth Edition(ICD-9)codes were used to identify patients in our sample.Demographic variables,hospital characteristics,payer status,medical comorbidities and mortality rates were compared between the two procedures.Multivariate logistic regression analysis was then performed to identify independent risk factors of treatment utilized.RESULTS Of the total 502060 patients who were treated for femoral neck fracture,51568(10.3%)underwent THA and the incidence of THA rose from 8.3%to 13.7%.Private insurance accounted for a higher percentage of THA than hemiarthroplasty.THA increased most in urban teaching hospitals relative to urban non-teaching hospitals.Mean length of stay(LOS)was longer for HA.The mean charges were less for HA,however charges decreased steadily for both groups.HA had a higher mortality rate,however,after adjusting for age and comorbidities HA was not an independent risk factor for mortality.Interestingly,private insurance was an independent predictor for treatment with THA.CONLUSION There has been an increase in the use of THA for the treatment of femoral neck fractures in the United States,most notably in urban hospitals.HA and THA are decreasing in total charges and LOS.

Direct rapid determination of traces of sulfide in environment samples

An improved ethylene blue method for determination of sulfide is developed. It has been adapted to a direct determination of sulfide by both common spectrophotometric method and total differential spectrophotometric method. In common spectrophotometric method, the calibration curve is A=1.69ρ + 0.006 and the correlation coefficient is 0.9994.The apparent molar absorptivity is 5.42×10 4 L·mol -1 ·cm -1 and calibration curve is liner when ρ is in the range of 0 0.9 mg·L -1 . In total differential spectrophotometric method, the calibration curve is A=9.25ρ +0.004 and the correlation coefficient is 0.9996. The apparent molar absorptivity is 2.96×10 5 L·mol -1 ·cm -1 and calibration curve is liner when ρ is in the range of 0 0.10 mg·L -1 . The sensitivity of this method is increased significantly compared with the former ethylene blue method. The speed of reaction is also faster than the former one. The limit of detection is found to be 1.0 ng·mL -1 by both common spectrophotometric method and total differential spectrophotometric method. Ten replicate analyses of a sample solution containing 100 ng·mL -1 sulfide give a relative standard deviation of 1.8%. The effects of various cations and anions on the determination of sulfide are studied and procedures for removal of interference is described. The method is used for the determination of sulfide in environment samples with satisfactory results.

Multi-scale spatial relationships between soil total nitrogen and influencing factors in a basin landscape based on multivariate empirical mode decomposition

The relationships between soil total nitrogen(STN)and influencing factors are scale-dependent.The objective of this study was to identify the multi-scale spatial relationships of STN with selected environmental factors(elevation,slope and topographic wetness index),intrinsic soil factors(soil bulk density,sand content,silt content,and clay content)and combined environmental factors(including the first two principal components(PC1 and PC2)of the Vis-NIR soil spectra)along three sampling transects located at the upstream,midstream and downstream of Taiyuan Basin on the Chinese Loess Plateau.We separated the multivariate data series of STN and influencing factors at each transect into six intrinsic mode functions(IMFs)and one residue by multivariate empirical mode decomposition(MEMD).Meanwhile,we obtained the predicted equations of STN based on MEMD by stepwise multiple linear regression(SMLR).The results indicated that the dominant scales of explained variance in STN were at scale 995 m for transect 1,at scales 956 and 8852 m for transect 2,and at scales 972,5716 and 12,317 m for transect 3.Multi-scale correlation coefficients between STN and influencing factors were less significant in transect 3 than in transects 1 and 2.The goodness of fit root mean square error(RMSE),normalized root mean square error(NRMSE),and coefficient of determination(R2)indicated that the prediction of STN at the sampling scale by summing all of the predicted IMFs and residue was more accurate than that by SMLR directly.Therefore,the multi-scale method of MEMD has a good potential in characterizing the multi-scale spatial relationships between STN and influencing factors at the basin landscape scale.

Study on the Extraction Process of Total Flavonoids from Morinda citrifolia L.

[Objectives]This study was conducted to explore the best extraction technology of total flavonoids from Morinda citrifolia L.[Methods]An orthogonal test was carried out to select the best extraction process with the yield of total flavonoids in the extract as the investigation index.[Results]Among the four factors of experimental design,the extraction time had a very significant impact on the results,the ethanol concentration had a significant impact on the results,and the extraction temperature and ethanol dosage had no significant impacts on the results.The optimal extraction process conditions for the total flavonoids of M.citrifolia were as follows:extraction time 1.5 h,ethanol concentration 90%,extraction temperature 60-65℃,and ethanol dosage 1∶20(g/ml).The total flavonoids in M.citrifolia fruit were extracted according to the optimal extraction process conditions,and the yield was 2.936%.[Conclusions]This study provides a theoretical basis for obtaining the optimal extraction process conditions for total flavonoids of M.citrifolia.

Statistical Tests of the Validation of TCO Satellite Measurements, Recorded Simultaneously by TOMS-OMI (2005) and OMI-OMPS (2012-2018)

Two statistical validation methods were used to evaluate the confidence level of the Total Column Ozone (TCO) measurements recorded by satellite systems measuring simultaneously, one using the normal distribution and another using the Mann-Whitney test. First, the reliability of the TCO measurements was studied hemispherically. While similar coincidences and levels of significance > 0.05 were found with the two statistical tests, an enormous variability in the levels of significance throughout the year was also exposed. Then, using the same statistical comparison methods, a latitudinal study was carried out in order to elucidate the geographical distribution that gave rise to this variability. Our study reveals that between the TOMS and OMI measurements in 2005 there was only a coincidence in 50% of the latitudes, which explained the variability. This implies that for 2005, the TOMS measurements are not completely reliable, except between the -50° and -15° latitude band in the southern hemisphere and between +15° and +50° latitude band in the northern hemisphere. In the case of OMI-OMPS, we observe that between 2011 and 2016 the measurements of both satellite systems are reasonably similar with a confidence level higher than 95%. However, in 2017 a band with a width of 20° latitude centered on the equator appeared, in which the significance levels were much less than 0.05, indicating that one of the measurement systems had begun to fail. In 2018, the fault was not only located in the equator, but was also replicated in various bands in the Southern Hemisphere. We interpret this as evidence of irreversible failure in one of the measurement systems.

基于总安全系数法的喷射混凝土支护承载能力的试验研究

为验证总安全系数法中喷层的荷载结构模型及其安全系数计算方法,研制大型隧道结构模型试验系统,采取结构试验的方法,开展毛洞、不同厚度喷层以及二次衬砌的加载破坏试验。通过围岩和细砂材料的三轴试验明确模型试验中各材料的物理与力学参数,模拟毛洞、不同厚度喷层以及二次衬砌的加载破坏全过程,依据破坏状态明确喷层与二次衬砌的设计承载能力,试验中监测围岩应力应变、喷层内外侧应变和喷层位移,结合监测结果分析喷层与二次衬砌在承载过程中的变形特征与受力特征,明晰喷层与二次衬砌的承载机制,并与总安全系数法理论计算结果进行对比分析。结果表明:1)在试验断面条件下喷层受力状态为小偏心受压,喷层与围岩之间的粘结能有效传递剪力,从而减少了喷层的弯矩,有利于充分发挥喷层的抗压强度,同厚度情况下喷层的设计承载力要高于二次衬砌;2)试验得到的厚度为2 cm和4 cm喷层的设计承载力比总安全系数法理论计算结果分别大27.0%和22.9%,表明总安全系数法的喷层承载力计算模型是合理的,并具有合适的安全性。

在役螺栓超声三维成像监测数据的智能化分析方法

螺栓是一种常见的机械连接件,一旦失效,可能会导致设备损坏、结构崩塌,甚至危及人身安全。因此,在役螺栓的监测一直受到广泛关注。将相控阵超声全聚焦技术应用于螺栓在役监测,开发了专用系统和阵列探头,实现了三维成像可视化监测,改变了螺栓监测数据单一的现状。针对大量三维图像化数据处理的关键问题,提出了智能化分析方法,对比分析了决策树、支持向量机和神经网络算法的适用性,最终开发了基于决策树算法的智能分析评价软件模块并取得了较好的检测效果。

全腔肺吻合术后患儿运动耐量状况及相关危险因素分析

目的:探查全腔肺吻合术(TCPC)后患儿运动耐量状况及引起运动耐量下降的危险因素。方法:对2021年3月至2023年6月在我院接受心肺运动试验(CPET)的81例TCPC术后患儿进行回顾性研究。分析相关CPET参数,并根据最大摄氧量(VO_(2)max)占预计值百分比情况将患儿分为运动耐量较差组(VO_(2)max占预计值百分比<60%,n=61)和运动耐量较好组(VO_(2)max占预计值百分比≥60%,n=20),分析影响心肺运动功能的危险因素。结果:81例患儿平均年龄(12.28±3.28)岁,VO_(2) max占预计值百分比为(55.43±14.80)%。运动耐量较好组的最大单位体重摄氧量[(30.26±3.16)ml/kg vs.(20.55±4.26)ml/kg]、变时性指数[(0.63±0.15) vs.(0.46±0.18)]、随功率增加的摄氧量[(11.89±2.43)ml/(min·W) vs.(9.88±2.25)ml/(min·W)]以及单位体重氧摄取效率斜率[(36.49±6.16)ml/(log L·kg)vs.(26.83±6.38)ml/(log L·kg)]较运动耐量较差组均更好(P均<0.01)。两组的最大呼吸末二氧化碳、二氧化碳通气当量斜率、运动振荡通气发生率等差异均无统计学意义(P均> 0.05)。多因素Logistic回归分析表明,年龄、体重指数和变时性指数是运动耐量较差的危险因素;最大单位体重摄氧量和无氧阈时随功率增加的摄氧量是发生运动振荡通气的危险因素。结论:TCPC术后患儿运动耐量普遍下降,表现为有氧运动能力受损,其危险因素为年龄、体重指数和变时性指数。最大单位体重摄氧量和无氧阈时随功率增加的摄氧量为术后运动振荡通气危险因素。

植物样品中全氮含量测定的方法研究

为了更加高效安全地测定植物和食品样品中全氮含量,参考GB 5009.5—2016《食品安全国家标准食品中蛋白质的测定》方法,采用全自动凯氏定氮仪法,对称样量、试剂用量、消解方式、温度等条件进行了优化。改进后方法测定植物标准物质氮含量结果与标准物质氮含量定值的误差在0.67%~6.45%,测定结果的RSD值在0.51%~3.71%,加标回收率在95.2%~104.1%。改进后方法,降低了实验成本,减轻了实验过程中废弃排放物对环境造成的影响,提高了消解效率和实验人员的安全性。精密度及准确性等符合检测分析要求,适用于批量植物样品全氮含量的检测。

息半夏总生物碱的提取工艺优化及其生物活性分析

以息半夏的块茎为原料,乙醇为超声波辅助提取溶剂,考察乙醇体积分数、超声时间、料液比、超声温度等单因素对总生物碱提取率的影响,设计正交试验优化提取工艺,并测试总生物碱的体外抗氧化和降血糖活性。结果表明,最佳提取条件为乙醇体积分数65%、提取时间60 min、料液比1∶45、超声温度65℃,总生物碱的提取率达0.502%;总生物碱对DPPH、ABTS自由基的清除率分别达89.90%和43.60%,对α-葡萄糖苷酶的抑制率达86.40%。该工艺简单可行,总生物碱表现出良好的体外抗氧化和降血糖生物活性。

正交试验法优化紫苏叶中总黄酮提取工艺及体外抗氧化活性研究

试验以紫苏叶为研究对象,在单因素试验基础上,通过正交试验优化紫苏叶总黄酮的提取工艺,探讨总黄酮的抗氧化活性。以紫苏叶总黄酮得率为考察指标,对乙醇浓度、液料比、提取温度和提取时间进行优化。结果表明,4个因素对紫苏叶总黄酮得率影响的主次顺序为:提取温度>乙醇浓度>液料比>提取时间。紫苏叶总黄酮最优提取工艺参数为乙醇浓度50%、液料比20 mL/g、提取温度70℃和提取时间45 min。在此条件下,紫苏叶总黄酮得率为4.05%。紫苏叶总黄酮对DPPH自由基与羟自由基具有较强的清除作用,其IC50值分别为160 mg/L和196 mg/L。研究表明,紫苏叶总黄酮具有较强的抗氧化性能,是一种优质的天然抗氧化物质。

亚硝酸盐对焦酚红法检测24 h尿液总蛋白的干扰分析

目的探讨亚硝酸盐对于焦酚红法检测24 h尿液总蛋白的干扰效应,并评估维生素C纠正干扰的可行性。方法根据美国临床和实验室标准协会(CLSI)EP7-A3文件,选取24 h尿液总蛋白定量结果为150 mg/L、500 mg/L和1000 mg/L的新鲜尿液标本作为对照样本,并配制含不同浓度亚硝酸钠的干扰物样本。利用配对差异实验确认亚硝酸盐的干扰作用,并通过剂量效应实验明确亚硝酸盐浓度与干扰程度的关系。在终浓度为200μg/mL亚硝酸钠存在的情况下,评估不同浓度维生素C纠正干扰的效果。同时收集61例亚硝酸盐阳性和40例亚硝酸盐阴性的临床标本,比较两组标本维生素C纠正前后的相对差值,评估其临床应用价值。结果配对差异实验中200μg/mL亚硝酸钠对150 mg/L和500 mg/L两个浓度的尿总蛋白测定分别存在-157.8%和-36.2%的相对干扰,显著大于1/2TEa(22%),而对于高浓度1000 mg/L的尿总蛋白虽存在-20.5%的负干扰,但在可接受范围内。剂量效应实验结果显示随着尿液中亚硝酸盐浓度的增加,尿总蛋白检测所受负干扰作用亦逐渐增大。在终浓度为200μg/mL亚硝酸钠存在的情况下,添加0.2 mg/mL的维生素C可分别将150 mg/L和500 mg/L的尿总蛋白纠正至148 mg/L(-1.1%)和402 mg/L(-19.5%),均处于可接受范围内。临床标本中亚硝酸盐阳性组通过维生素C纠正产生的相对差值显著高于亚硝酸盐阴性组(P<0.01)。结论亚硝酸盐对于焦酚红法检测尿液总蛋白存在负干扰,尤其是在尿总蛋白150 mg/L情况下,需引起临床实验室的关注。添加0.2 mg/mL维生素C可有效纠正低浓度尿总蛋白标本中亚硝酸盐的干扰作用,具有一定的临床应用价值。