Strength reduction factors for seismic analyses of buildings exposed to near-fault ground motions

To estimate the near-fault inelastic response spectra, the accuracy of six existing strength reduction factors （R） proposed by different investigators were evaluated by using a suite of near-fault earthquake records with directivity-induced pulses. In the evaluation, the force-deformation relationship is modelled by elastic-perfectly plastic, bilinear and stiffness degrading models, and two site conditions, rock and soil, are considered. The R-value ratio （ratio of the R value obtained from the existing R-expressions （or the R-p-T relationships） to that from inelastic analyses） is used as a measurement parameter. Results show that the R-expressions proposed by Ordaz ＆ Perez-Rocha are the most suitable for near-fault ground motions, followed by the Newmark ＆ Hall and the Berrill et al. relationships. Based on an analysis using the near-fault ground motion dataset, new expressions of R that consider the effects of site conditions are presented and verified.

Near-infrared photoimmunotherapy of pancreatic cancer using an indocyanine green-labeled anti-tissue factor antibody

AIM To investigate near-infrared photoimmunotherapeutic effect mediated by an anti-tissue factor(TF) antibody conjugated to indocyanine green(ICG) in a pancreatic cancer model.METHODS Near-infrared photoimmunotherapy(NIR-PIT) is a highly selective tumor treatment that utilizes an antibody-photosensitizer conjugate administration, followed by NIR light exposure. Anti-TF antibody 1849-ICG conjugate was synthesized by labeling of rat IgG2 b anti-TF monoclonal antibody 1849(anti-TF 1849) to a NIR photosensitizer,ICG. The expression levels of TF in two human pancreatic cancer cell lines were examined by western blotting. Specific binding of the 1849-ICG to TF-expressing BxPC-3 cells was examined by fluorescence microscopy. NIR-PITinduced cell death was determined by cell viability imaging assay. In vivo longitudinal fluorescence imaging was used to explore the accumulation of 1849-ICG conjugate in xenograft tumors. To examine the effect of NIRPIT, tumor-bearing mice were separated into 5 groups:(1) 100 μg of 1849-ICG i.v. administration followed by NIR light exposure(50 J/cm2) on two consecutive days(Days 1 and 2);(2) NIR light exposure(50 J/cm2) only on two consecutive days(Days 1 and 2);(3) 100 μg of 1849-ICG i.v. administration;(4) 100 μg of unlabeled antiTF 1849 i.v. administration; and(5) the untreated control. Semiweekly tumor volume measurements, accompanied with histological and immunohistochemical(IHC) analyses of tumors, were performed 3 d after the 2nd irradiation with NIR light to monitor the effect of treatments. RESULTS High TF expression in BxPC-3 cells was observed via western blot analysis, concordant with the observed preferential binding with intracellular localization of 1849-ICG via fluorescence microscopy. NIR-PIT-induced cell death was observed by performing cell viability imaging assay. In contrast to the other test groups, tumor growth was significantly inhibited by NIR-PIT with a statistically significant difference in relative tumor volumes for 27 d after the treatment start date [2.83 ± 0.38(NIR-PIT) vs 5.42 ± 1.61(Untreated), vs 4.90 ± 0.87(NIR), vs 4.28 ±1.87(1849-ICG), vs 4.35 ± 1.42(anti-TF 1849), at Day 27, P < 0.05]. Tumors that received NIR-PIT showed evidence of necrotic cell death-associated features upon hematoxylin-eosin staining accompanied by a decrease in Ki-67-positive cells(a cell proliferation marker) by IHC examination.CONCLUSION The TF-targeted NIR-PIT with the 1849-ICG conjugate can potentially open a new platform for treatment of TF-expressing pancreatic cancer.

IMPROVEMENT OF REGIONAL PREDICTION OF SEA FOG ON GUANGDONG COASTLAND USING THE FACTOR OF TEMPERATURE DIFFERENCE IN THE NEAR-SURFACE LAYER

The relationship between the factor of temperature difference of the near-surface layer(T_(1000 hPa)-T_(2m))and sea fog is analyzed using the NCEP reanalysis with a horizontal resolution of l°xl°(2000 to 2011) and the station observations(2010 to 2011).The element is treated as the prediction variable factor in the GRAPES model and used to improve the regional prediction of sea fog on Guangdong coastland.(1) The relationship between this factor and the occurrence of sea fog is explicit:When the sea fog happens,the value of this factor is always large in some specific periods,and the negative value of this factor decreases significantly or turns positive,suggesting the enhancement of warm and moist advection of air flow near the surface,which favors the development of sea fog.(2) The transportation of warm and moist advection over Guangdong coastland is featured by some stages and the jumping among these states.It also gets stronger over time.Meanwhile,the northward propagation of warm and moist advection is quite consistent with the northward advancing of sea fog from south to north along the coastland of China.(3) The GRAPES model can well simulate and realize the factor of near-surface temperature difference.Besides,the accuracy of regional prediction of marine fog,the relevant threat score and Heidke skill score are all improved when the factor is involved.

Necessity and adequacy of near-source factors for not-so-tall fixed-base buildings

Nonlinear response history analyses and use of strong ground motion data including near-field effects has become a common practice in both performance based design of tall buildings and design of base-isolated buildings. On the other hand, ordinary buildings are commonly analysed via response spectrum analysis following the rules of conventional seismic codes, most of which do not take near-field effects into account. This study evaluates the necessity and the adequacy of near-source factors for ordinary fixed-base buildings that are not specifically classified as tall, by comparing dynamic responses of 3, 8, and 15-story benchmark buildings obtained via （1） linear time history analyses using 220 record components from 13 historical earthquakes and 45 synthetic earthquake records of different magnitudes and fault distances and （2） response spectrum analyses in accordance with the Turkish Earthquake Code 2007 -representing seismic codes not taking near-field effects into account- and the Uniform Building Code 1997 which takes near-field effects into account via near-source factors that amplify design response spectrum. It is shown that near-source factors are crucial for the safe design of not-so-tall ordinary fixed-base buildings but those defined in UBC97 may still not be adequate for those located in the vicinity of the fault.

玉米基肥期农田土壤氨挥发量与近地表氨浓度相关性研究

农田氨排放量与近地表氨浓度密切相关,但两者能否相互转换还缺乏系统研究。基于此,以近地表氨浓度经典方法(被动法)为主要使用方法,以传统海绵法为对照方法,在豫南砂姜黑土开展5种典型施肥处理玉米季基肥期氨排放量与近地表氨浓度的相关性研究。结果发现,不同施肥处理的氨挥发峰值均出现在施肥后的2-4 d,第5天开始显著降低,第8天之后基本与对照无明显差异;不同处理的氨累计排放量差别较大,排序为TR>OPT>SOPT>HK>CK,累计排放量分别为7.68、5.48、3.37、2.78和0.22 kg·hm^(-2);同时发现,不同施肥处理近地表氨浓度也有相同趋势,峰值同样出现在施肥后的2-4 d,第5天开始显著降低,平均氨质量浓度排序为TR>OPT>SOPT>HK>CK,均值分别为17.5、11.6、10.7、8.21和1.70μg·m^(-3)。线性相关性分析表明,施肥后前8 d不同施肥处理的氨挥发量与近地表氨浓度的线性相关性较强,而8 d之后两者的相关性较弱,说明近地表氨浓度和农田氨挥发量的相关性与农田氨挥发量的高低有关。除此之外,不同方法中被动法对低施氮量和缓释肥的估算优于排放因子法,而排放因子法对高施肥条件下氨挥发量的估算优于被动法。整体而言,被动方法估算氨挥发量的相对误差介于-15.9%-17.5%之间,排放因子法相对误差介于-54.3%-81.8%之间,被动方法明显具备更高的估算精度。以上结果说明,被动方法可以潜在替代传统氨监测方法估算大区域农田氨挥发量,但估算精度主要集中在高氨排放期。

Spatial distribution of near-fault ground motion

Near-fault strong ground motion of strike-slip and dip-slip of vertical and inclined rectangular fault in half-space and layered half-space is analyzed by dislocation source model. The Fourier spectra ratio of ground motion is adopted to study the characteristics of near-fault ground motion. For both slip models, near-fault strong ground motion with high amplitude is located in a narrow belt area along the projection of the fault on the ground and mainly controlled by the sub-faults nearby. Directivity of strike-slip fault is more dominant in long period for components perpendicular to the fault, and more dominant in long period for components parallel to the fault for dip-slip fault. The deeper the location of the source is, the more slowly the amplitude of ground motion attenuates. There is obvious hanging wall effect in ground motion of inclined fault, and the spatial distribution of ground motion is asymmetric which coincides with observational data. Finally, a fitting function of spatial distribution for near-fault ground motion is proposed and compared with near source factors of the 1997 Uniform Building Code of USA.

四川盆地蓬莱气区近地表Q场求取及应用

近地表吸收衰减会严重降低地震资料的分辨率,利用微测井资料对近地表吸收结构进行估算,获得表层介质品质因子Q值,再进行反Q滤波补偿,可实现高保真、高分辨率的“双高”处理目的。为此,提出一种改进的谱比法对单井微测井数据进行Q值求取,然后通过拟合表层速度与Q值关系,将近地表速度(V)场转换成近地表Q场。四川盆地的表层较薄,层析反演的近地表速度场深度采样间隔为10 m,难以反映近地表厚度为几米的表层变化。为此,首先结合双井微测井数据的多炮拟合算法,求取浅层比较薄的表层等效Q值;其次结合地面地震的振幅及旅行时信息求取表层的相对Q场;然后用双井微测井求得的绝对Q值对相对Q场进行标定;最后将该表层平面Q场镶嵌在用Q-V拟合关系转换的近地表Q场的浅层,得到该工区优化的近地表Q场,用于地震资料的近地表Q补偿,从而达到拓宽频带、提高地震资料的分辨率的目的。

基于分解法的Neumann 边界条件反散射问题

利用分解法研究Neumann边界条件下障碍物反散射问题和腔体反散射问题.该方法利用近场测量数据可以同时处理障碍物反散射问题和腔体反散射问题,而不需要对测量面和散射体之间的距离做任何渐近假设.首先给出两个反散射问题的数学模型,以及利用双层势能算子的跳跃关系和格林公式给出双层势能算子的相关估计结果.其次通过定义算子分别研究障碍物和腔体近场算子的分解情况.最后构造障碍物和腔体在Neumann边界条件下的成像函数.

近场的分类及其与静态场的关系

在局域源所产生的电磁场中,以波长为特征长度可以引入两个重要概念:近场和远场。准静态场是另一重要概念。回溯人类对电磁场的认识过程,从一开始分立的静态电/磁场,到麦克斯韦方程组所描述的完整的运动电磁场,经历了认识的飞跃。有限的时间频率是运动电磁场的重要特征量。本文以不同维度的辐射源为例,分析了其产生的近场和远场,区分了两种产生近场的机制,并阐述了近场和静态场的关系。最后,本文以介质平板中的法布里-珀罗共振和金属颗粒的表面等离激元共振为例,揭示了不同维度下近场对能量储存的贡献及其与不同维度微腔的品质因子巨大差异的直接关系。

Spatial distribution of near-fault ground motion

Near-fault strong ground motion of strike-slip and dip-slip of vertical and inclined rectangular fault in half-space and layered half-space is analyzed by dislocation source model. The Fourier spectra ratio of ground motion is adopted to study the characteristics of near-fault ground motion. For both slip models, near-fault strong ground motion with high amplitude is located in a narrow belt area along the projection of the fault on the ground and mainly controlled by the sub-faults nearby. Directivity of strike-slip fault is more dominant in long period for components perpendicular to the fault, and more dominant in long period for components parallel to the fault for dip-slip fault. The deeper the location of the source is, the more slowly the amplitude of ground motion attenuates. There is obvious hanging wall effect in ground motion of inclined fault, and the spatial distribution of ground motion is asymmetric which coincides with observational data. Finally, a fitting function of spatial distribution for near-fault ground motion is proposed and compared with near source factors of the 1997 Uniform Building Code of USA.

Combining Environmental Factors and Lab VNIR Spectral Data to Predict SOM by Geospatial Techniques

Soil organic matter(SOM) is an important parameter related to soil nutrient and miscellaneous ecosystem services. This paper attempts to improve the performance of traditional partial least square regression(PLSR) model by considering the spatial autocorrelation and soil forming factors. Surface soil samples(n = 180) were collected from Honghu City located in the middle of Jianghan Plain, China. The visible and near infrared(VNIR) spectra and six environmental factors(elevation, land use types, roughness, relief amplitude, enhanced vegetation index, and land surface water index) were used as the auxiliary variables to construct the multiple linear regression(MLR), PLSR and geographically weighted regression(GWR) models. Results showed that: 1) the VNIR spectra can increase about 39.62% prediction accuracy than the environmental factors in predicting SOM; 2) the comprehensive variables of VNIR spectra and the environmental factors can improve about 5.78% and 44.90% relative to soil spectral models and soil environmental models, respectively; 3) the spatial model(GWR) can improve about 3.28% accuracy than MLR and PLSR. Our results suggest that the combination of spectral reflectance and the environmental variables can be used as the suitable auxiliary variables in predicting SOM, and GWR is a promising model for predicting soil properties.

Response spectrum of seismic design code for zones lack of near-fault strong earthquake records

It was shown from the study on the recently near-fault earthquake ground motions that the near-fault effects were seldom considered in the existing Chinese seismic code. Referring to the UBC97 design concept for near-fault factors, based on the collected world-widely free-site records of near-fault earthquakes ground motions classified by earthquake magnitude and site condition, the attenuation relationship expressions of the acceleration spectrum demand at the key points within the long period and moderate period were established in term of the earthquake magnitude and the site condition. Furthermore, the near-fault factors＇ expressions about the earthquake magnitude and the fault distance were deduced for the area lack of near-fault strong earthquake records. Based on the current Chinese Building Seismic Design Code, the near-fault effect factors and the modified design spectral curves, which were valuable for the seismic design, were proposed to analyze the seismic response of structures.

近壁面空化冲击颗粒破碎效果的影响因素研究

为提升近壁面空化冲击的颗粒破碎效率,对颗粒破碎效果的影响因素开展了研究。首先确定了液相中空化冲击破碎颗粒的基本方式:近壁面空泡溃灭时产生的高速微射流会驱动空泡内部的颗粒撞击壁面,造成颗粒破碎。由颗粒破碎的基本方式确定了影响颗粒破碎效果的主要因素;理论分析了微细颗粒穿过流体空化泡壁的动态过程,计算了不同粒径的运动颗粒能够穿过空化泡壁的初始速度及初始距离条件;分析了颗粒粒径大小对于近壁面空化泡溃灭微射流的削弱作用,计算了近壁面空化冲击破碎颗粒的无量纲距离条件。基于理论分析结果,开展了基于颗粒体积分数、入口压力、颗粒大小及转速率等多因素的石英砂颗粒球磨空化冲击破碎实验。结果表明,实验后各实验点的中位粒径D_(50)和特征粒径D_(10)均明显减小,粒径小于10μm的颗粒占比由实验前的6.2%提升至59.3%,验证了上述因素对颗粒破碎效果的影响作用。

Effect of Skin Pigmentation on Near Infrared Spectroscopy

The purpose of this study was to determine the effects of skin pigmentation regarding Near Infrared Spectroscopy (NIRS) tissue oxygen saturation values (StO2). The study examined NIRS values in individuals with varying skin pigmentation on the anterior compartment of the lower leg and volar forearm to determine if correlation exists among three NIRS devices, the EQUANOX, Casmed, and INVOS. Skin pigmentation was measured on the anterior lower leg (AL) and volar forearm (VF) of participants using a noninvasive colorimeter that employed reflective spectroscopy to produce a quantitative value for erythema (skin “redness”) and melanin (skin pigment). Muscle oxygenation was measured using three oximetry devices with sensors placed in the same areas. The EQUANOX device showed no significant correlation with skin pigmentation, while the Casmed and INVOS devices showed moderate and significant correlation with skin pigmentation, respectively. Different devices have different abilities to remove confounding variables, such as skin pigmentation and erythema, which may affect clinical decision-making, and affect the use of NIRS technology.

Influence of chelator and near-infrared dye labeling on biocharacteristics of dual-labeled trastuzumab-based imaging agents

Objective： To investigate the effect of fluorescent dye labeling on the targeting capabilities of 111 In- （DTPA）.-trastuzumab-（IRDye 800）m. Methods： Trastuzumab-based conjugates were synthesized and conjugated with diethylenetriaminepentaacetic acid （DTPA） at molar ratios of I, 2, 3 and 5 and with a fluorescent dye （IRDye 800CW） at molar ratios of 1, 3 and 5. Immunoreactivity and internalization were assessed on SKBR-3 cells, overexpressing human epidermal growth factor receptor 2. The stability in human serum and phosphate-buffered saline （PBS） was evaluated. The biodistribution of dual-labeled conjugates was compared with that of 111In-（DTPA）2-trastuzumab in a SKBR-3 xenograft model to evaluate the effect of dye-to-protein ratio. Results： All trastuzumab-based conjugates exhibited a high level of chemical and optical purity. Flow cytometry results showed that increasing dye-to-protein ratios were associated with decreased immunoreactivity. Stability studies revealed that the conjugate was stable in PBS, while in human serum, increased degradation and protein precipitation were observed with increasing dye-to-protein ratios. At 4 h, the percentages of internalization of dual-labeled conjugates normalized by dye-to-protein ratio （m） were 24.88%±2.10%, 19.99%±0.59%, and 17.47%±1.26% for ＂m＂ equal to 1, 3, and 5, respectively. A biodistribution study revealed a progressive decrease in tumor uptake with an increase in the dye-to-protein ratios. The liver, spleen and kidney showed a marked uptake with increased dye-to-protein ratios, particularly in the latter. Conclusions： With non-specific-site conjugation of the fluorescent dye with a protein based on imaging agent, the increase in dye-to-protein ratios negatively impacted the immunoreactivity and stability, indicating a reduced tumor uptake.

Correlation of prefrontal activity measured by near-infrared spectroscopy (NIRS) with mood, BDNF genotype and serum BDNF level in healthy individuals

Depression has been known to reduce the prefrontal activity associated with the execution of certain cognitive tasks, although whether a temporarily depressed or anxious mood in healthy individuals affects the prefrontal blood oxygen level during cognitive tasks is unknown. Combining the measurement of prefrontal activity with near-infrared spectroscopy (NIRS) and the two cognitive tasks, namely the letter version of the verbal fluency test (VFT-l) and the Stroop test, we measured the effect of a depressed or anxious mood and gender on the changes in the prefrontal oxygenated hemoglobin (Oxy-Hb) levels during those cognitive tests in healthy individuals. Depressed mood or anxious mood was assessed by the Hospital Anxiety and Depression Scale (HADS). Thereby we aimed to explore the possibility of NIRS measurement for detecting the early subclinical manifestation of major depression. Moreover, we examined the possible relationships between prefrontal activation and the functional Val66Met polymorphisms of the brain derived neurotropic factor (BDNF) gene and serum BDNF level. As a result, the increased prefrontal Oxy-Hb levels during cognitive tasks were significantly correlated with the severity of depressed mood in males. The course of the prefrontal Oxy-Hb increase was different depending on the cognitive tasks, i.e., the VFT-l or the Stroop test, in both genders. Correlations of BDNF genotype and serum BDNF level with the prefrontal Oxy-Hb levels during those cognitive tasks were negative. Our results suggest that the early subclinical manifestation of depressed mood in males might be detected by the NIRS measurement, which is not correlated with the individual properties of BDNF.

基于有序Probit模型的铁路险兆事件影响因素识别研究

为识别铁路险兆事件的影响因素,以宜春车务段2017年9月—2017年10月共1870条数据为样本,以铁路险兆事件等级为因变量,事件原因、环境特征和事件特征为自变量建立有序Probit模型,探究人、设备、环境和管理因素对铁路险兆事件严重影响程度。研究结果表明:设备设施未按规定防护是影响严重性险兆事件发生的主要因素;与其他人为因素相比,未执行相关作业规定对增加险兆事件严重程度有显著作用。研究结果可为铁路管理部门实现事故预控提供依据。

考虑近断层方向性效应的速度脉冲放大作用预测模型

近断层速度脉冲型地震动对结构有特殊的破坏作用。所以在近断层概率地震危险性分析以及工程抗震设计时需要考虑速度脉冲的影响。而传统地震动预测模型往往会低估速度脉冲的影响。因此,如何可靠地估计速度脉冲的影响是近年来研究的重要课题之一。该研究以NGA-West2数据库为基础,另外收集近年最新获取的近断层地震动记录,考虑脉冲方向的不确定性,基于小波方法定量进行速度脉冲识别,共获得316条速度脉冲记录。基于该数据,采用最小二乘法拟合得到新的速度脉冲放大作用分段预测模型,并与已有的速度脉冲放大作用预测模型进行比较,验证了其有效性。该模型考虑了近年实际地震动观察结果,在已有的速度脉冲放大作用预测模型基础上,进一步提高了脉冲放大系数的平台高度。基于所提出的脉冲放大作用经验预测模型,通过对传统地震动预测模型进行修正从而对近断层速度脉冲型地震动进行了有效估计。

隧道电子雷管爆破近区振动测试研究

隧道爆破逐渐以电子雷管替代导爆管雷管,以往的爆破振动规律主要以导爆管雷管爆破而得到的,不适合电子雷管爆破振动的预测和控制。以人和场隧道为工程背景,进行了隧道电子雷管连续起爆试验,采用定制大量程速度传感器测试掌子面后方5 m范围内的边墙振动速度。利用最小二乘法对4种不同振动传播路径进行研究,给出最佳计算振动速度的传播路径,回归得出隧道电子雷管爆破掌子面后方边墙振动速度计算公式。所得的隧道电子雷管爆破近区振动规律,可以有效地预测隧道电子雷管爆破近区和远区振动速度。