Effects of leaf N concentration and leaf area index on determining rice tillering

Relative tillering rate(RTR)increased linear-ly with the increasing of leaf N concentration(NLV)has been already reported.To testwhether this relationship could be used toquantitatively explain the difference in tilleringamong a wide range of N application,field ex- periments were conducted at the IRRI farm,Los Banos,Laguna,the Philippines.Two in- dica cultivars,IR 72 and IR68284H wereused.For each cultivar,12 treatments includ- ing 4 N levels(0,60,120,and 180kgN·ha)and 3 transplanting spacing(30×20,20×20,and 10×20cm)were arranged in a ran-domized split-plot design with 4 replications.The N treatments were designated as mainplots and spacings as subplots.Fourteen-day-old seedlings were transplanted with 3seedlings per hill.The subplot area was 20m~2.Nitrogen fertilizer was applied as basal,atmidtillering,and at panicle initiation in threeequal splits.P,K,and Zn were applied asbasal at normal dosage.The field was flooded.Plant samples were taken every 7-14 d from 14d after transplanting to flower

Clinical significance of melatonin concentrations in predicting the severity of acute pancreatitis

AIM: To assess the value of plasma melatonin in predicting acute pancreatitis when combined with the acute physiology and chronic health evaluation?II?(APACHEII) and bedside index for severity in acute pancreatitis (BISAP) scoring systems.METHODS: APACHEII and BISAP scores were calculated for 55 patients with acute physiology (AP) in the first 24 h of admission to the hospital. Additionally, morning (6:00 AM) serum melatonin concentrations were measured on the first day after admission. According to the diagnosis and treatment guidelines for acute pancreatitis in China, 42 patients suffered mild AP (MAP). The other 13 patients developed severe AP (SAP). A total of 45 healthy volunteers were used in this study as controls. The ability of melatonin and the APACHEII and BISAP scoring systems to predict SAP was evaluated using a receiver operating characteristic (ROC) curve. The optimal melatonin cutoff concentration for SAP patients, based on the ROC curve, was used to classify the patients into either a high concentration group (34 cases) or a low concentration group (21 cases). Differences in the incidence of high scores, according to the APACHEII and BISAP scoring systems, were compared between the two groups.RESULTS: The MAP patients had increased melatonin levels compared to the SAP (38.34 ng/L vs 26.77 ng/L) (P = 0.021) and control patients (38.34 ng/L vs 30.73 ng/L) (P = 0.003). There was no significant difference inmelatoninconcentrations between the SAP group and the control group. The accuracy of determining SAP based on the melatonin level, the APACHEII score and the BISAP score was 0.758, 0.872, and 0.906, respectively, according to the ROC curve. A melatonin concentration ≤ 28.74 ng/L was associated with an increased risk of developing SAP. The incidence of high scores (≥ 3) using the BISAP system was significantly higher in patients with low melatonin concentration (≤ 28.74 ng/L) compared to patients with high melatonin concentration (> 28.74 ng/L) (42.9% vs 14.7%, P = 0.02). The incidence of high APACHEII scores (≥ 10) between the two groups was not significantly different.CONCLUSION: The melatonin concentration is closely related to the severity of AP and the BISAP score. Therefore, we can evaluate the severity of disease by measuring the levels of serum melatonin.

Er^(3+) ion concentration effect on transient and steady-state behavior in Er^(3+):YAG crystal

The effect of Er3＋ ion concentration on transient and steady-state behavior in 45-nm Er3＋ ：YAG crystal is investigated. It is shown that by changing the signal field, the coherent field and the concentration of Er3＋ ions in the crystal, the absorption, dispersion, and group index of the weak probe field can be adjusted. Also, it is found that the probe absorption occurs in the presence of population inversion and probe amplification is obtained in the absence of population inversion.

Characteristics Analysis of Chemical Concentration Sensor Based on Three-layer FBG

The three-layer structure model of the fiber Bragg grating is proposed in this paper. And through experimental study and reasoning calculation to verify the three layer structure of the optical waveguide model, so the sensitivity characteristic of the Bragg wavelength to the refractive index of chemical solution is obtained. And the relationships between the concentration and the shift of Bragg wavelength of sucrose, ethanol, and Nacl solution are achieved. Finally the shifts of the Bragg wavelength with the external concentration are obtained by experiments. A kind of simple structure, small size, good stability, high sensitivity chemical concentration sensor is obtained.

The Activity Concentrations, Radiation Contamination, and Hazards from Wastes and Soil Samples in Nasirabad Industrial Area, Chattogram, Bangladesh

Soils and other solid wastes from industrial areas of Nasirabad, Chattogram are usually dumped or used for land development. Information about the radioactivity level presented on these soil and wastes enables one to assess any possible radiological hazard to humankind by the use of such materials. A total of 37 (31 soils and 6 solid waste) samples near from different types of industries along four kilometre range were collected. The presence and activity concentrations of naturally occurred radioactive materials (NORM) and anthropogenic radionuclides in the samples were estimated using HPGe detector of 40% relative efficiency. The activity concentration of 226Ra, 232Th and 40K were found to be ranging from 8 ± 2 to 131 ± 18.33 with an average of 21 Bq·kg-1, 10 ± 2.69 to 133 ± 15.96 with an average of 40 Bq·kg-1 and 81 ± 22.68 to 930 ± 260.40 with an average of 449 Bq·kg-1 respectively. Besides this, some hazard indices like, the radium equivalent activity (Raeq), external hazard index (Hex), internal hazard index (Hin), and the activity concentration index (Iy) were calculated to assess the radiation hazard in this region. The averages of calculated hazard indices were within the normal limits, except the activity concentration index, which shows elevated values. The outcomes of this study could serve as important baseline radiological data for future epidemiological studies and environmental monitoring initiatives in the study area.

Concentration Analysis of the Hungarian Mangalica Pig Stock

In the animal raising sector of Hungary, the indigenious and special Hungarian product called Mangalica pig has a special significance. Some descriptions were made about the species but the concentration of this segment has not been examined, that is why the aim of the researchers is to analyse the concentration of the Mangalica population on the basis of various statistical methods in the last 10 years. The certain concentration indexes were the following the concentration ratio, the Lorenz-curve, the Gini-coefficient, the Herfindahl-index and the redundancy index. Through the analysis we realised that from 2000 a kind of concentration started, which in case of the concentration ratio, the Lorenz-curve and the Gini-coefficient were in 2001 and 2003 of the highest ratio. The Herfindal-index and redundancy index showed that the years of 2000 and 2002 were the most significant, because of a number of large-scale producers started their activities or developed their stocks in these years. On the basis of the results, it can be stated that in the years before the application and after the recession the concentration of the stock was instable, while at the beginning of the supporting period until the crisis the appearance of large-scale firms became equal but basically according to every index the concentration in the examined years was approximately average.

A Self-Organizing RBF Neural Network Based on Distance Concentration Immune Algorithm

Radial basis function neural network(RBFNN) is an effective algorithm in nonlinear system identification. How to properly adjust the structure and parameters of RBFNN is quite challenging. To solve this problem, a distance concentration immune algorithm(DCIA) is proposed to self-organize the structure and parameters of the RBFNN in this paper. First, the distance concentration algorithm, which increases the diversity of antibodies, is used to find the global optimal solution. Secondly,the information processing strength(IPS) algorithm is used to avoid the instability that is caused by the hidden layer with neurons split or deleted randomly. However, to improve the forecasting accuracy and reduce the computation time, a sample with the most frequent occurrence of maximum error is proposed to regulate the parameters of the new neuron. In addition, the convergence proof of a self-organizing RBF neural network based on distance concentration immune algorithm(DCIA-SORBFNN) is applied to guarantee the feasibility of algorithm. Finally, several nonlinear functions are used to validate the effectiveness of the algorithm. Experimental results show that the proposed DCIASORBFNN has achieved better nonlinear approximation ability than that of the art relevant competitors.

Assessment of Heavy Metal Concentration and Evaluation of Health Risk of Some Vegetables Cultivated in Loumbila Farmland, Burkina Faso

Vegetables such as spinach, African eggplant, cabbage, eggplant, okra, chili peppers and tomatoes are found in our everyday foods and are the most important dietary source of nutrient. But, it becomes deleterious to human as well as animals as it accumulates toxic metals in their tissue when grown in contaminated soil. The mostly consumed vegetables like spinach, African eggplant (fruit and leaves), Corchorus olitorius leaf, Amaranthus hybridus leaf, cabbage, eggplant, okra, pepper and tomato were collected from Loumbila market gardening. Heavy metals copper (Cu), nickel (Ni), lead (Pb), chromium (Cr), cadmium (Cd) and zinc (Zn) were measured using atomic absorption spectrophotometer (AAS) model AANALYST 200 from PERKIN ELMER. The results of this study showed that the concentrations of lead (0.49 to 8.59 mg/kg) and zinc (20.73 to 71.29 mg/kg) in spinach, African eggplant (fruit and leaves), Corchorus olitorius leaf, Amaranthus hybridus leaf, cabbage, eggplant, okra, pepper and tomato exceeded the permissible level of FAO and WHO standard. The daily plant metal intake for Cd (0.001 - 0.015 mg/kg), Pb (0.041 - 0.730 mg/kg), and Cu (0.703 - 1.543 mg/kg) is higher than the recommended daily intake of metals but does not exceed the tolerable limit. The calculated values of the health risk indices show high values for Cd, Pb, Zn, Ni and Cu while low values are observed for Cr. Except for Cr, the IRS evaluated for all the studied metals were greater than one (IRS > 1). This implies that exposed populations are susceptible to developing diseases linked to the following metals: Cd, Pb, Zn, Ni and Cu.

Study of the relationship between dosage of oral progesterone and concentration of serum progesterone

Objective:To explore the relationship among body mass index(BMI),dosage of progesterone(P) and serum progesterone concentration,and provide reference for the clinical use of oral progesterone. Methods:This was a random,open-label,prospective clinical trial.Eighty women meeting the criteria for enrollment were recruited from July 2010 to March 2011 in outpatient clinic of Peking Union Medical College Hospital and given oral progesterone therapy for consecutive 10 days.They were randomly assigned into four groups according to the different doses of progesterone:group A 100 mg/day,group B 200 mg/day,group C 300 mg/day and group D 400 mg/day. Results:Seventy four patients(92.5%,74/80) accomplished the study.It can be observed that administration of different dosage of P could significantly increase serum P concentration(all P<0.001).And there was a positive correlation between the increase of P concentration and dosage(r_p=0.613,P<0.001).Furthermore,the medians of the increase of serum P concentration in 4 groups were 14.71 nmol/L in group A,28.47 nmol/L in group B, 58.89 nmol/L in group C,72.69 nmol/L in group D.When BMI<24 kg/m^2(42 cases),the median of the increase of P levels was 13.90 nmol/L,37.22 nmol/L,62.55 nmol/L,and 119.02 nmol/L in group A,B,C and D, respectively,while BMI≥24 kg/m^2(32 cases),the median of increase was 8.93 nmol/L,24.82 nmol/L,24.87 nmol/L,and 63.48 nmol/L,respectively.In addition,significant difference was found only in group D between women with BMI<24 kg/m^2 and with BMI≥24 kg/m^2(P = 0.010). Conclusions;Serum progesterone levels go up linearly with the dosage increasing.The greater BMI the patient have,the larger dosage may be needed to achieve the same serum progesterone concentration.The individual dosage of oral progesterone needed can be roughly calculated in the light of the result of this study.

一种基于迈克尔逊干涉仪的浓度/折射率在线测量系统的研究

浓度是表征溶液性质的重要物理参数之一。本文设计了一种基于旋转比色皿结合迈克尔逊干涉仪的浓度/折射率在线测量系统。将液体加入比色皿并旋转5°,利用CCD采集光强数据和自编的计数程序,可实时测量旋转前后干涉条纹移动数目之差,并由此计算NaCl和葡萄糖溶液的折射率和浓度。对质量百分比浓度为0、10%和20%的NaCl溶液进行了折射率测量和误差分析,发现与相关理论值的相对误差仅为0.61%、0.63%和2.2%。葡萄糖溶液的浓度—折射率关系曲线也呈现出线性良好、可靠性高的特点。总之,基于迈克尔逊干涉仪的浓度/折射率在线测量系统具有测量非接触、结果可靠、高效实用的特点。

煤自燃程序升温实验及其在实验教学中的应用

该文利用程序升温实验系统,对三种氧气浓度(20.9%、10%和7%)所代表的采空区散热带、氧化带、窒息带进行了煤样自燃发火实验,采集了不同温度阶段的气体产物,分析了温度及氧气浓度对气体产物浓度的影响,并对指标气体进行了详细分类和评估。实验结果表明:交叉点温度CPT随着氧气浓度的升高而降低,干空气的交叉点温度为144.6℃,由经验关系计算得到的CPT值与实验数据相差仅6.08%;氧气浓度越高,临界温度越低,所产生的气体浓度越高;CO气体在不同的含氧环境下都是主要的氧化产物,可作为判断煤自燃发火的主要指标,C_(2)H_(4)和C_(3)H_(6)的产生表示煤体进入加速氧化状态,可作为判断煤自燃发火的辅助指标。

福建省县域人口-经济时空分异及影响因素研究

根据人口、经济及其相关指标数据,运用人口地理集中度、经济地理集中度和人口-经济匹配指数,对福建省人口与经济之间耦合关系和空间差异进行研究,并对其影响因素进行分析。结果表明:人口地理集中度在阈值为1时呈现东—西两级分异;经济地理集中度在阈值为1时呈现闽东和闽东南集聚态势,将人口-经济匹配指数按3类划分,2010—2021年期间同类型县域逐渐呈现集聚效应,福建省县域人口-经济匹配度整体有趋好态势,但匹配程度仍有待提高,人口-经济稳定型逐渐形成一个“U”字形,与福建省“十四五”规划较为吻合,说明该划分有利于宏观决策。在今后的发展中,福建省仍要注重区域间人口与经济发展水平相协调。

干旱半干旱地区城市公园绿地空气负离子浓度特征及影响因素

为研究干旱半干旱地区城市公园绿地空气负离子浓度(NAIC)特征及影响因素,以呼和浩特市敕勒川公园为对象,于2020—2021年,每个季节选取晴天、晴间多云为主的天气各10 d,同步监测07:00—19:00时段,5种不同结构绿地(乔草型、乔灌型、乔木型、灌草型、乔灌草型)及对照区(CK)空气负离子浓度及PM10、PM2.5、温度、湿度、风速、大气压强、噪声等环境指标。结果表明:不同结构绿地空气负离子浓度季节日变化有所差异;同一季节,复杂结构绿地空气负离子浓度均值较高,不同结构绿地之间空气负离子浓度均值差异不显著;同一结构绿地,夏、秋季空气负离子浓度均值显著高于春、冬季;不同结构绿地空气清洁度夏、秋季较高,空气清洁度评价指数均值分别为0.58~0.78、0.52~0.80。绿地结构、季节对空气负离子浓度影响为主效应,绿地结构×季节对空气负离子浓度交互作用不显著;除此之外,相对湿度、PM10、PM2.5是影响空气负离子浓度的主要因素。

基于分子动力学聚合物改性沥青黏附性能研究

为了增强基质沥青与集料之间界面黏附性,选取PE、SBS、SBR、PU 4种代表性聚合物对其进行改性,采用分子动力学模拟法对沥青-集料和沥青-水-集料模型进行不同工况模拟,并通过室内试验验证模拟结果。通过分析相对浓度分布曲线得到沥青极性组分的变化规律,研究不同温度下各改性沥青混合料黏附性并根据相对浓度参数对其机理进行分析,通过聚合物改性性能对比,得出其适用条件。结果表明:PE与沥青相溶性好,但PE改性沥青混合料水稳定性较差;SBS改性沥青能在温差较大的环境中保持较高的黏附性;SBR改性沥青低温条件下黏附性突出,且水稳定性优越,适用于低温多雨的地区;PU改性沥青综合性能较好,在高温多雨等气候条件复杂的环境中适用性较强。

武汉城市森林空气环境效应研究——以九峰国家森林公园为例

为探究城市森林空气环境的变化规律,以九峰国家森林公园为研究对象,以空气负离子浓度为主要监测指标,同步监测空气温、湿度,空气颗粒物浓度等,阐明其季节性变化规律,探索影响空气负离子浓度的主要因素。结果表明:森林环境可以显著改善空气温度、湿度,春季和秋季各林分的林内环境均达到“体感舒适”等级;与对照相比,各林分类型对PM_(1.0)、PM_(2.5)和PM_(10)有明显净化效果,其中秋季林分净化率高于夏季,春季最低,针叶+常绿阔叶林的颗粒物净化率相对较高;空气负离子浓度总体表现为夏季>春季>秋季,春季和秋季各林分空气负离子浓度的峰值出现时间主要集中在16∶00,夏季则是在10∶00;影响空气负离子浓度的主要因素在不同季节存在差异,各类型颗粒物浓度、天空开阔度在各季节均与负离子浓度呈极显著或显著负相关关系;空气负离子浓度在春季与空气湿度呈显著正相关,在夏季与树高呈显著正相关,在秋季则与空气温度、叶面积指数和树高表现出显著正相关关系。

我国交叉性金融业务分析与穿透式监管指数编制初探

中央金融工作会议提出防范风险跨区域、跨市场传递共振,中国人民银行提出构建以资管产品为代表的交叉性金融业务风险监测评估框架。通过对交叉性金融概念、衍生背景、演变历程、运行状况的分析,为提升我国交叉性金融风险管控能力提供有益参考。在交叉性金融统计数据缺口较大和信息公开程度较低的情况下,通过对资管产品与银行理财产品发展情况的分析了解我国交叉性金融业务的演变特征,同时通过构造投资广度指数与投资集中度指数为交叉性金融业务的穿透式监管提供有益的分析工具。研究发现,我国交叉性金融业务取得了长足的发展,交叉性金融业务野蛮扩张的势头得到了有效控制,交叉性金融业务发展的业务模式和资金运用方式都呈现出新的变化趋势。对投资广度指数和投资集中度指数进行试算分析发现,构造投资广度指数与集中度指数,能够加强对交叉性金融业务投资复杂程度的把握,仅依托公开数据即可初步实现穿透式监管。由于交叉性金融业务的底层资产难以穿透,蕴含着较大的系统性风险,因此应该规范交叉性金融业务活动,加强穿透式监管,避免金融风险的跨机构、跨市场传递共振;金融监管部门与金融机构应该积极依托业务数据对交叉性金融活动开展常规性和专项性的穿透式监管。

中国农业废弃物源活性氮排放特征、驱动因素及差异性分析

旨在研究农业废弃物源活性氮排放规律和监测活性氮污染,进而为减少活性氮排放量和提高氮污染治理公平提供理论依据,研究首先采用排放因子法测算了1990—2019年全国农业废弃物源活性氮排放量,并分析确定了我国(除港澳台之外)31个省级行政区域的活性氮排放特征。然后利用LMDI模型和集中指数法分别研究农业废弃物源活性氮排放变化量的驱动因素和活性氮排放量的地区差异性。结果发现,1990—2019年,全国农业废弃物源活性氮排放量在1996年达到峰值,整体呈现“M”型变化趋势;全国范围内人均活性氮排放强度呈现以胡焕庸线为界的西北低密度—东南高密度的格局。基于农产品前端消费及其农业废弃物末端处置2个维度来考察活性氮的排放特征,从农产品消费端来看,消费肉类农产品生产活性氮排放量占比(36.75%)最高,其中,牛羊肉类农产品占比高达22%;从农业废弃物末端处置来看,处置畜禽粪尿产生的活性氮占比较高,且对畜禽粪尿和秸秆而言直接排放与燃烧还田均是活性氮排放量较高的2种处置方式。国家层面农业废弃物源活性氮排放量的驱动因素为经济发展效应,而省级层面农业废弃物源活性氮排放变化量的主要驱动因素为经济发展效应、购买能力效应和消费结构效应。活性氮排放总量、人均活性氮和地均活性氮排放量均是农业经济强省较高,这些省份承担了更多的氮污染环境压力。

2005-2021年我国卫生人力资源发展趋势及公平性分析

背景“健康中国2030”战略对卫生人力资源配置提出了更高需求,国内开展了较多地区卫生人力资源公平性的评价研究,但尚无从全国视角对我国多种医疗机构、多类别卫生人力资源进行的概述。目的对2005—2021年全国31省(自治区、直辖市)12类医疗卫生机构、5类卫生人力资源进行趋势描述和公平性分析,为未来各卫生机构人力资源配置优化提供参考。方法全国卫生人力资源数据来自《中国卫生统计年鉴(2006—2012)》《中国卫生和计划生育统计年鉴(2013—2017)》《中国卫生健康统计年鉴(2018—2022)》,人口数据和经济数据来自《中国统计年鉴(2006—2022)》。计算2005—2021年各省(自治区、直辖市)各类医疗卫生机构、各类卫生人力资源的人均占有量,计算年均增长率和集中指数(CI)以描述发展趋势,并根据经济发展水平进行公平性分析。结果2005—2021年,我国卫生人员总量持续上升,年均增长率为5.58%,农村地区增长较快,年均增长率达10.87%。在各类医疗卫生机构中,社区卫生服务中心(站)的卫生人员数增速最快(年均增长率达18.05%),卫生监督所(中心)的人员数增速较低(年均增长率为0.18%),疾病预防控制中心的卫生人员数总体呈下降趋势(年均增长率为-0.39%)。除社区卫生服务中心(站)外,各类医疗机构卫生人员总数的CI<0.20。结论我国各类医疗卫生机构人力资源人均占有量在农村地区增长较快,地区间人均资源分配的公平性尚佳,但总量不足,重要机构和人员类别需要注意。要继续加强农村卫生人力资源的投入,国家和各省(自治区、直辖市)要稳定公共卫生队伍,健全基层医疗卫生服务发展,提高公平性与可及性。

我国高龄老人家庭灾难性卫生支出及其不平等研究——基于CFPS数据的实证分析

目的:测算我国高龄老人家庭灾难性卫生支出发生现状,分析灾难性卫生支出不平等趋势及贡献因素。方法:基于中国家庭追踪调查2012—2020年数据,测算高龄老人家庭灾难性卫生支出发生率和发生强度,利用Logit回归、多元线性回归、集中指数及其分解方法估计灾难性卫生支出的影响因素、不平等及相关因素贡献度。结果:中国高龄老人家庭灾难性卫生支出发生风险较高、强度较大,存在倾向于低收入家庭的不平等。家庭存款、家庭人均收入、家庭净资产、老人身体健康程度、老人拥有组织成员身份是灾难性卫生支出不平等的主要正向贡献因素,伴侣健在对灾难性卫生支出的不平等有一定负向贡献。结论:政策制定应考虑相关影响因素,为高龄老人群体提供相应的经济风险保护。

基于全球视角下的口腔癌疾病负担公平性分析

目的研究1990—2019年由社会经济发展水平差异所致的全球口腔癌疾病负担不平等情况,为制定有效的预防和控制政策提供科学依据。方法本研究的疾病负担数据来源于2019年全球疾病负担研究,人类发展指数(human development index,HDI)来自于《2020年人类发展报告》,采用线性回归分析年龄标化的伤残调整寿命年(disability-adjusted life yeas,DALY)率与HDI的相关性,使用不平等斜率指数(slope index of inequality,SII)和集中指数(concentration index,CI)评价1990—2019年全球口腔癌疾病负担的不公平情况及发展趋势。结果本研究共纳入189个国家和地区,2019年口腔癌DALY率为46.61[IQR(30.70,64.97)],线性回归结果显示口腔癌DALY率与HDI水平呈显著负相关(ρ=-0.06,P<0.001)。口腔癌DALY负担在189个国家和地区间表现出显著的不平等性,2019年SII值为-107.16[95%CI(-127.60,-90.69)],1990—2019年SII值<0且绝对值呈上升趋势;2019年口腔癌CI值为-1.35[95%CI(-2.88,-1.01)],1990—2015年CI值>0且呈下降趋势,而2016—2019年CI值<0且绝对值呈上升趋势。结论1990—2019年全球口腔癌疾病负担存在明显的社会不公平现象,口腔癌疾病负担更集中在低社会经济发展水平国家,且随着时间变化呈现出加重趋势。因此,未来应注重发展中国家的医疗资源分配问题,采取更有针对性的措施,有效控制口腔癌疾病负担的不平等现状。