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Strength reduction factors for seismic analyses of buildings exposed to near-fault ground motions 被引量:2
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作者 Qu Honglue Zhang Jianjing J.X. Zhao 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2011年第2期195-209,共15页
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... 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. 展开更多
关键词 strength reduction factors near-fault ground motion response spectra force-deformation relationship
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Near-infrared photoimmunotherapy of pancreatic cancer using an indocyanine green-labeled anti-tissue factor antibody 被引量:7
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作者 Winn Aung Atsushi B Tsuji +4 位作者 Aya Sugyo Hiroki Takashima Masahiro Yasunaga Yasuhiro Matsumura Tatsuya Higashi 《World Journal of Gastroenterology》 SCIE CAS 2018年第48期5491-5504,共14页
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(... 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. 展开更多
关键词 PANCREATIC cancer Anti-tissue factor ANTIBODY Indocyanine green Photoimmunotherapy near-INFRARED
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IMPROVEMENT OF REGIONAL PREDICTION OF SEA FOG ON GUANGDONG COASTLAND USING THE FACTOR OF TEMPERATURE DIFFERENCE IN THE NEAR-SURFACE LAYER 被引量:1
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作者 黄辉军 黄健 +2 位作者 刘春霞 毛伟康 毕雪岩 《Journal of Tropical Meteorology》 SCIE 2016年第1期66-73,共8页
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 201... 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. 展开更多
关键词 weather prediction regional prediction of marine fog Guangdong coastland GRAPES model factor of near-surface temperature difference
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Necessity and adequacy of near-source factors for not-so-tall fixed-base buildings
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作者 Cenk Alhan Melih Sürmeli 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2015年第1期13-26,共14页
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 buildin... 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. 展开更多
关键词 near-field effects near-source factors low-rise buildings mid-rise buildings
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Spatial distribution of near-fault ground motion 被引量:17
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作者 刘启方 袁一凡 金星 《地震学报》 CSCD 北大核心 2004年第2期183-192,共10页
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 ... 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. 展开更多
关键词 近场强地面运动 断层 方向性 近场修正因子 震源位错模型 空间分布
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2019-2022年安徽省危重孕产妇医院监测结果分析
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作者 吕丽君 李涛 吴言 《安徽医学》 2025年第1期106-110,共5页
目的 分析危重孕产妇监测相关数据,为此类人群的早期识别和干预提供参考。方法 利用中国危重孕产妇监测系统收集2019-2022年安徽省18所医院孕产妇信息资料,分析危重孕产妇发生情况和特征,采用单因素分析和广义线性回归模型分析危重孕产... 目的 分析危重孕产妇监测相关数据,为此类人群的早期识别和干预提供参考。方法 利用中国危重孕产妇监测系统收集2019-2022年安徽省18所医院孕产妇信息资料,分析危重孕产妇发生情况和特征,采用单因素分析和广义线性回归模型分析危重孕产妇发生的影响因素。结果 2019-2022年安徽省共18所医院共有孕产妇253 495例,其中危重孕产妇1 880例,危重孕产妇检出率为7.42‰;危重孕产妇疾病谱以凝血功能障碍检出率最高,占比80.96%。单因素分析发现,高龄(年龄≥35岁)、婚姻状况为单身、产前检查次数<5次、经产妇、既往有剖宫产史的危重孕产妇检出率较高,差异有统计学意义(P <0.05)。广义线性回归模型分析发现,高龄(RR=1.852,95%CI:1.639~2.092)、既往剖宫产史(RR=1.445,95%CI:1.275~1.637)、产前检查次数<5次(RR=2.910,95%CI:2.604~3.252)的孕产妇对危重孕产妇检出率的影响较大。结论 安徽省危重孕产妇检出率较高,危重孕产妇疾病谱以凝血功能障碍为主,应加强对贫血和出血性疾病的防治,规范开展产前检查,重点关注高龄、既往剖宫产史等高危孕产妇。 展开更多
关键词 危重孕产妇 医院监测 疾病谱 影响因素
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近红外光谱法在食品营养成分检测中的应用研究
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作者 高浩 高媛惠 薛颖 《食品安全导刊》 2025年第3期156-158,164,共4页
随着食品行业的快速发展,消费者对食品营养成分的关注度日益提升,精准检测食品营养成分愈发重要。但传统检测手段常面临操作复杂、耗时久等问题,难以满足当下高效检测需求。近红外光谱法因具备检测速度快、能同时分析多种成分且对样品... 随着食品行业的快速发展,消费者对食品营养成分的关注度日益提升,精准检测食品营养成分愈发重要。但传统检测手段常面临操作复杂、耗时久等问题,难以满足当下高效检测需求。近红外光谱法因具备检测速度快、能同时分析多种成分且对样品无损等优势,逐渐被应用于食品营养成分检测领域,但其在应用过程中易受环境、样品特性及仪器等因素的干扰,影响检测效果。基于此,本文分析了近红外光谱法在食品营养成分检测中的应用,探讨近红外光谱法检测的影响因素,并提出了相应的控制举措,以期保障食品营养成分检测质量。 展开更多
关键词 近红外光谱法 食品营养成分检测 应用 影响因素
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Spatial distribution of near-fault ground motion 被引量:2
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作者 LIU Qi-fang(刘启方) +3 位作者 YUAN Yi-fan(袁一凡) JIN Xing(金星) 《Acta Seismologica Sinica(English Edition)》 CSCD 2004年第2期200-210,共11页
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 ... 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. 展开更多
关键词 near-fault strong ground motion dislocation model DIRECTIVITY near source factor
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Combining Environmental Factors and Lab VNIR Spectral Data to Predict SOM by Geospatial Techniques 被引量:2
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作者 GUO Long ZHANG Haitao +1 位作者 CHEN Yiyun QIAN Jing 《Chinese Geographical Science》 SCIE CSCD 2019年第2期258-269,共12页
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) mod... 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. 展开更多
关键词 VISIBLE near infrared spectral reflectance environmental factors spatial characteristics partial least SQUARES regression geographically weighted regression
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Response spectrum of seismic design code for zones lack of near-fault strong earthquake records
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作者 李新乐 窦慧娟 +1 位作者 朱晞 孙建刚 《Acta Seismologica Sinica(English Edition)》 CSCD 2007年第4期447-453,共7页
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-... 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. 展开更多
关键词 near-fault strong earthquake records spectral demand design response spectrum near-fault effect factor
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Effect of Skin Pigmentation on Near Infrared Spectroscopy
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作者 Luke Couch Mellisa Roskosky +1 位作者 Brett A. Freedman Michael S. Shuler 《American Journal of Analytical Chemistry》 2015年第12期911-916,共6页
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 varyin... 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. 展开更多
关键词 near Infrared Spectroscopy SKIN CHROMOPHORES CONFOUNDING factorS VARIABILITY between MANUFACTURERS
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方案设计阶段的严寒地区近零碳小型办公建筑影响因子研究
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作者 李辰琦 任航 《沈阳建筑大学学报(自然科学版)》 CAS 北大核心 2024年第6期1060-1067,共8页
目的以实现建筑近零碳为目标,研究严寒地区小型办公建筑的设计影响因子及其参数控制。方法以沈阳建筑大学近零碳示范项目为例,采用天正软件模拟分析形体、平面形式、朝向、中庭比例、窗墙比、光伏屋面倾角等关键因子对建筑碳排放影响,... 目的以实现建筑近零碳为目标,研究严寒地区小型办公建筑的设计影响因子及其参数控制。方法以沈阳建筑大学近零碳示范项目为例,采用天正软件模拟分析形体、平面形式、朝向、中庭比例、窗墙比、光伏屋面倾角等关键因子对建筑碳排放影响,进而利用Pearson相关性系数法对这些因子进行分析,确定最佳参数。结果通过模拟得出宜选取布局紧凑的混合式办公空间的平面布局、建筑朝向为南偏西0°~30°、形体规则且体型系数为0.26~0.3、中庭比例为5∶3到2∶1、窗墙比为0.3~0.4、光伏屋面角度为10°~25°;影响因子的重要性排序从大到小依次为体型系数、光伏屋面角度、窗墙比、中庭比例、建筑朝向、平面形式;模拟得出目标建筑比基础建筑总碳排放量减少了2177039.72 kg,碳排放降低率为83%。结论充分考虑建筑的关键设计因子影响并合理控制相关参数,通过正向设计可有效降低碳排放,实现近零碳化目标。 展开更多
关键词 近零碳化 影响因子 参数控制 碳排放
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Influence of chelator and near-infrared dye labeling on biocharacteristics of dual-labeled trastuzumab-based imaging agents
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作者 Xuejuan Wang Melissa B Aldrich +4 位作者 Zhi Yang Nina Zhou Qing Xie Chen Liu Eva Sevick-Muraca 《Chinese Journal of Cancer Research》 SCIE CAS CSCD 2016年第3期362-369,共8页
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 w... 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. 展开更多
关键词 INFLUENCE near infrared dye TRASTUZUMAB human epidermal growth factor receptor 2 dual-labeled
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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
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作者 吕金岭 尤克 +3 位作者 何斌 刘霜 梁少民 郭战玲 《生态环境学报》 CSCD 北大核心 2024年第3期399-407,共9页
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... 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。 展开更多
关键词 氨挥发 被动法 近地表氨浓度 相关性 排放因子法 玉米季
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Correlation of prefrontal activity measured by near-infrared spectroscopy (NIRS) with mood, BDNF genotype and serum BDNF level in healthy individuals
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作者 Daisuke Matsuzawa Kotaro Takeda +8 位作者 Hiroyuki Ohtsuka Jun Takasugi Takashi Watanabe Junko Maeda Saeka Nagakubo Chihiro Sutoh Ichiro Shimoyama Ken Nakazawa Eiji Shimizu 《Open Journal of Psychiatry》 2012年第3期194-203,共10页
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 prefron... 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. 展开更多
关键词 near-INFRARED Spectroscopy (NIRS) Depression ANXIETY Brain Derived Neurotropic factor (BDNF)
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四川盆地蓬莱气区近地表Q场求取及应用 被引量:1
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作者 韩嵩 陈康 +3 位作者 汤聪 王静 张茜 彭浩天 《石油地球物理勘探》 EI CSCD 北大核心 2024年第3期443-453,共11页
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... 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。 展开更多
关键词 近地表 品质因子Q Q值估算 表层Q场 四川盆地
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正交三偶极子阵列MIMO雷达近场目标定位
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作者 张万军 王威龙 +1 位作者 刘尉悦 陈华 《信号处理》 CSCD 北大核心 2024年第10期1813-1821,共9页
本文基于发射端和接收端都配备了正交三偶极子阵列的双基地多输入多输出(Multiple-Input MultipleOutput,MIMO)雷达系统,结合三线性分解提出了一种近场源多维参数估计算法。该算法首先利用接收端匹配滤波器的输出数据构建了一个三阶平... 本文基于发射端和接收端都配备了正交三偶极子阵列的双基地多输入多输出(Multiple-Input MultipleOutput,MIMO)雷达系统,结合三线性分解提出了一种近场源多维参数估计算法。该算法首先利用接收端匹配滤波器的输出数据构建了一个三阶平行因子(Parallel Factor,PARAFAC)模型。同时为了加快算法的收敛速度以及避免所提算法对迭代的初值敏感,利用复平行因子分析(COMplex parallel FACtor analysis,COMFAC)算法来得到发射阵列和接收阵列导向矩阵的估计值。接着,根据发射阵列导向矩阵和接收阵列导向矩阵的结构特征得到每个目标的波离角(Direction-of-Departure,DOD)和波达角(Direction-of-Arrival,DOA)的粗估计值,并且基于双基地MIMO雷达阵列系统的几何关系得到从发射阵列到目标的距离以及从目标到接收阵列的距离的粗估计值。最后,基于得到的近场多维参数的粗估计值得到发射阵列和接收阵列的空间相位估计值,并进而从空间相位的估计值中得到更精确的DOD,DOA,从发射阵列到目标的距离和从目标到接收阵列的距离的精估计值。该算法适用于阵元间距为半波长的均匀线性阵列,相比于传统近场定位需满足阵元间隔为四分之一波长的前提,所提的MIMO阵列系统降低了阵列孔径损失,同时所提算法不需要进行谱峰搜索以及额外的参数配对操作。仿真结果表明,基于正交三偶极子阵列的MIMO雷达测向算法较传统标量阵列的算法具有较高的参数估计精度。 展开更多
关键词 正交三偶极子阵列 多输入多输出雷达 近场 平行因子
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基于分解法的Neumann 边界条件反散射问题
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作者 刘颖 刘立汉 《中山大学学报(自然科学版)(中英文)》 CAS CSCD 北大核心 2024年第3期172-178,共7页
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... 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. 展开更多
关键词 反散射 近场测量 分解法
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近场的分类及其与静态场的关系
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作者 许书侨 詹影 +1 位作者 唐誉婷 韩德专 《物理与工程》 2024年第2期153-160,共8页
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... 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。 展开更多
关键词 近场 静态场 品质因子 维度性 格林函数
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嘉兴市2019~2021年新生儿听力筛查、诊断、随访现状分析
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作者 薛秋霞 《中华耳科学杂志》 CSCD 北大核心 2024年第6期1044-1047,共4页
目的分析嘉兴市新生儿听力筛查与诊断现状,从而获得影响听力诊断、随访的因素,从而提高新生儿听力筛查诊断质量。方法对2019年至2021年出生于嘉兴市五县两区需要开展听力检测的118513例新生儿进行初筛,初筛未通过者42 d内复筛,复筛未通... 目的分析嘉兴市新生儿听力筛查与诊断现状,从而获得影响听力诊断、随访的因素,从而提高新生儿听力筛查诊断质量。方法对2019年至2021年出生于嘉兴市五县两区需要开展听力检测的118513例新生儿进行初筛,初筛未通过者42 d内复筛,复筛未通过者转至市听力诊治机构,采用听性脑干反应(auditory brainstem response,ABR)、声导抗等方法检测,对异常者追踪随访。根据2019年至2021年嘉兴市新生儿听力筛查年度报表和随访结果,分析2019年至2021年嘉兴市新生儿听力筛查、诊断、随访现状以及主要的影响因素。结果2019年至2021年新生儿活产总数为118513例,实际完成初筛人数为118371例,初筛率为99.88%。初筛未通过12203例,复筛11953例,复筛率为97.95%,最终确诊异常429例,听力异常率为3.61‰。听力异常患儿经过随访发现,未复诊的患儿主要原因为:(1)失访:电话不正确或者未接听(41.43%,104/251);(2)上级医院进一步检查(25.10%,63/251);(3)家长认知不足,拒绝复诊(19.12%,48/251);(4)人员流动,已回老家(7.17%,18/251);(5)腭裂或存在耳朵畸形(7.17%,18/251)。结论2019至2021年嘉兴市新生儿听力初筛率维持在较高水平,虽然复筛率均满足考核条件,但对听力异常患儿的随访还不足。因此如何减少听力异常患儿的失访量、增加早期干预量将成为今后嘉兴听力筛查项目中的关键,也是听力筛查的终极目的。 展开更多
关键词 新生儿听力筛查 诊断 随访 影响因素
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