Dosimetric Effects Due to Inter-Observer Variability of Organ Contouring When Utilizing a Knowledge-Based Planning System for Prostate Cancer

Purpose: Radiotherapy is a widely accepted standard of care for early-stage prostate cancer, and it is believed that the plan quality and treatment outcome are associated with contour accuracy of both the target and organs-at-risk (OAR). The purposes of this study are to 1) assess geometric and dosimetric uncertainties due to inter-observer contour variabilities and 2) evaluate the effectiveness of geometric indicators to predict target dosimetry in prostate radiotherapy. Methods: Twenty prostate patients were selected for this retrospective study. Five experienced clinicians created unique structure sets containing prostate, seminal vesicles, bladder, and rectum for each patient. A fully automated script and knowledge-based planning routine were utilized to create standardized and unbiased plans that could be used to evaluate changes in isodose distributions due to inter-observer variability in structure segmentation. Plans were created on a “gold-standard” structure set, as well as on each of the user-defined structure sets. Results: Inter-observer variability of contours during structure segmentation was very low for clearly defined organs such as the bladder but increased for organs without well-defined borders (prostate, seminal vesicles, and rectum). For plans generated with the user-defined structure sets, strong/moderate correlations were observed between the geometric indicators for target structure agreement and target coverage for both low-risk and intermediate-risk patient groups, while OAR indicators showed no correlation to final dosimetry. Conclusions: Target delineation is crucial in order to maintain adequate dosimetric coverage regardless of the associated inter-observer uncertainties in OAR contours that had a limited impact upon final dosimetry.

Chemical Interaction UO2Cl2 with α-and β-Amino Acids in Aqueous and Organic Solution

This paper presents the results of the search of biologically active uranium compounds such as amino acids. We first received and examined X-ray and IR （infrared radiation） spectroscopy of uranium complexes with α- and β-amino acids in aqueous and organic solution. We proposed a method for direct synthesis of complex organic compounds of uranium chloride UO2Cl2 with α- andβ-amino acids for the synthesis of drugs for the treatment of cancer.

Asymmetric Synthesis of (-)-1-Trimethylsilyl-ethanol with Immobilized Saccharomyces Cerevisiae Cells in Water/Organic Solvent Diphasic System

Asymmetric synthesis of (-)-1-trimethylsilyl-ethanol with immobilized Saccharomyces cerevisiae cells in water/organic solvent biphasic system was studied. The effects of shake speed, hydrophobicity of organic solvent, volume ratio of water phase to organic phase, pH value of aqueous phase and reaction temperature on the initial reaction rate, maximum yield and enantiomeric excess (ee) of the product were systematically explored. All the above-mentioned factors had significant influence on the reaction. n-Hexane was found to be the best organic solvent for the reaction. The optimum shake speed, volume ratio of water phase to organic phase, pH value and reaction temperature were 150 r.min-1, 1/2, 8 and 30 ℃ respectively, under which the maximum yield and enantiomeric excess of the product were as high as 96.8% and 95.7%, which are 15% and 16% higher than those of the corresponding reaction performed in aqueous phase. To our best knowledge, this is the most satisfactory result obtained.

Patterns of upper layer circulation variability in the South China Sea from satellite altimetry using the self-organizing map

Patterns of the South China Sea (SCS) circulation variability are extracted from merged satellite altimetry data from October 1992 through August 2004 by using the self-organizing map (SOM). The annual cycle, seasonal and inter-annual variations of the SCS surface circulation are identified through the evolution of the characteristic circulation patterns.The annual cycle of the SCS general circulation patterns is described as a change between two opposite basin-scale SW-NE oriented gyres embedded with eddies: low sea surface height anomaly (SSHA) (cyclonic) in winter and high SSHA (anticyclonic) in summer half year. The transition starts from July—August (January—February) with a high (low) SSHA tongue east of Vietnam around 12°~14° N, which develops into a big anticyclonic (cyclonic) gyre while moving eastward to the deep basin. During the transitions, a dipole structure, cyclonic (anticyclonic) in the north and anticyclonic (cyclonic) in the south, may be formed southeast off Vietnam with a strong zonal jet around 10°~12° N. The seasonal variation is modulated by the interannual variations. Besides the strong 1997/1998 event in response to the peak Pacific El Nio in 1997, the overall SCS sea level is found to have a significant rise during 1999~2001, however, in summer 2004 the overall SCS sea level is lower and the basin-wide anticyclonic gyre becomes weaker than the other years.

2D/2D S-scheme heterojunction with a covalent organic framework and g-C_(3)N_(4) nanosheets for highly efficient photocatalytic H2 evolution

The fabrication of S-scheme heterojunctions with fast charge transfer and good interface contacts,such as intermolecularπ–πinteractions,is a promising approach to improve photocatalytic performance.A unique two-dimensional/two-dimensional(2D/2D)S-scheme heterojunction containing TpPa-1-COF/g-C_(3)N_(4) nanosheets(denoted as TPCNNS)was developed.The established maximum interfacial interaction between TpPa-1-COF NS and g-C_(3)N_(4) NS may result in aπ–πconjugated heterointerface.Furthermore,the difference in the work functions of TpPa-1-COF and g-C_(3)N_(4) results in a large Fermi level gap,leading to upward/downward band edge bending.The spontaneous interfacial charge transfer from g-C_(3)N_(4) to TpPa-1-COF at theπ–πconjugated interface area results in the presence of a built-in electric field,according to the charge density difference analysis based on density functional theory calculations.Such an enhanced built-in electric field can efficiently drive directional charge migration via the S-scheme mechanism,which enhances charge separation and utilization.Thus,an approximately 2.8 and 5.6 times increase in the photocatalytic hydrogen evolution rate was recorded in TPCNNS-2(1153μmol g^(-1) h^(-1))compared to pristine TpPa-1-COF and g-C_(3)N_(4) NS,respectively,under visible light irradiation.Overall,this work opens new avenues in the fabrication of 2D/2Dπ–πconjugated S-scheme heterojunction photocatalysts with highly efficient hydrogen evolution performance.

A hybrid model for predicting spatial distribution of soil organic matter in a bamboo forest based on general regression neural network and interative algorithm

A general regression neural network model,combined with an interative algorithm(GRNNI)using sparsely distributed samples and auxiliary environmental variables was proposed to predict both spatial distribution and variability of soil organic matter(SOM)in a bamboo forest.The auxiliary environmental variables were:elevation,slope,mean annual temperature,mean annual precipitation,and normalized difference vegetation index.The prediction accuracy of this model was assessed via three accuracy indices,mean error(ME),mean absolute error(MAE),and root mean squared error(RMSE)for validation in sampling sites.Both the prediction accuracy and reliability of this model were compared to those of regression kriging(RK)and ordinary kriging(OK).The results show that the prediction accuracy of the GRNNI model was higher than that of both RK and OK.The three accuracy indices(ME,MAE,and RMSE)of the GRNNI model were lower than those of RK and OK.Relative improvements of RMSE of the GRNNI model compared with RK and OK were 13.6%and 17.5%,respectively.In addition,a more realistic spatial pattern of SOM was produced by the model because the GRNNI model was more suitable than multiple linear regression to capture the nonlinear relationship between SOM and the auxiliary environmental variables.Therefore,the GRNNI model can improve both prediction accuracy and reliability for determining spatial distribution and variability of SOM.

Crystal Growth, Thermal, Mechanical and Optical Properties of a New Organic Nonlinear Optical Material: Ethyl P-Dimethylamino Benzoate (EDMAB)

An organic material, namely, ethyl p-dimethylamino benzoate was crystallized for the first time by solution growth technique using pure and mixed solvents. Growth kinetics and morphology changes with solvents were investigated based on solute –solvent interactions of pure and mixed solvents. An appropriate mixed solvent for high quality crystals with well-defined morphology is reported. The absence of solvent molecules and the presence of various functional groups of the grown sample were qualitatively confirmed by FTIR spectroscopic studies. Thermal properties of the grown sample were analyzed by TG and DTA analysis. Mechanical properties of the EDMAB crystal were investigated by micro hardness studies. Moreover, the grown crystal shows high transparency in the visible and near IR regions. The material shows relatively high SHG efficiency than that of KDP.

STUDIES ON ORGANIC PEROXIDE/N, NDI(2-α-METHYL-ACRYLOYLOXY PROPYL)-PARA-TOLUIDINE BINARY SYSTEMS

The polymerization of methyl methacrylate (MMA) initiated by organic peroxide and polymerizable aromatic tertiary amine such as N, N-di (2-α-methylacryloyloxy propyl)-p-toluidine (MP)_2PT binary system has been studied. It was found that the (MP)_2PT promotes MMA polymerization, and the kinetics of MMA polymerization fits the radical polymerization rate equation. Based on the ESR studies and the end-group analysis the initiation mechanism is proposed.

Precipitation Regionalization Using Self-Organizing Maps for Mumbai City, India

The detailed analysis of individual rain events characteristics is an essential step for improving our understanding of variation in precipitation over different topographies. In this study, the homogeneity among rain gauges was investigated using the concept of “rain event properties,” linking them to the main atmospheric system that affects the rainfall in the region. For this, eight properties of more than 23,000 rain events recorded at 47 meteorological stations in Mumbai, India, were analyzed utilizing seasonal (June-September) rainfall records over 2006-2016. The high similarities among the properties indicated the similarities among the rain gauges. Furthermore, similar rain gauges were distinguished, investigated and characterized by cluster analysis using self-organizing maps (SOM). The cluster analysis results show six clusters of similarly behaving rain gauges, where each cluster addresses one isolated class of variables for the rain gauge. Additionally, the clusters confirm the spatial variation of rainfall caused by the complex topography of Mumbai, comprising the flatland near the Arabian Sea, high-rise buildings (urban area) and mountain and hills areas (Sanjay Gandhi National Park located in the northern part of Mumbai).

Nondoped-type White Organic Light-Emitting Diode Using Star-Shaped Hexafluorenylbenzene as an Energy Transfer Layer

White organic light-emitting diodes （WOLEDs） with a structure of indium-tin-oxide （ITO）/N,N＇-bis- （1-naphthyl）-N,N＇-diphenyl- （1, 1＇-biphenyl）-4,4＇-diamine （NPB）/1,2,3,4,5,6-hexakis（9,9-diethyl-9H-fluoren-2- yl）benzene （HKEthFLYPh）/5,6,11,12-tetraphenylnaphtacene （rubrene）/tris（8-hydroxyquinoline） aluminum （Alq3）/Mg：Ag were fabricated by vacuum deposition method, in which a novel star-shaped hexafluorenyl- benzene HKEthFLYPh was used as an energy transfer layer, and an ultrathin layer of rubrene was inserted between HKEthFLYPh and Alq3 layers as a yellow light-emitting layer instead of using a time-consuming doping process. A fairly pure WOLED with Commissions Internationale De L＇Eclairage （CIE） coordinates of （0.32, 0.33） was obtained when the thickness of rubrene was 0.3 nm, and the spectrum was insensitive to the applied voltage. The device yielded a maximum luminance of 4816 cd/m2 at 18 V.

GC-MS法测定水源水中的半挥发性有机物

我国于2002年6月1日实施了地表水环境质量标准(GB3838-2002),其中集中式生活饮用水地表水源地特定项目中规定了68种有机污染物的监测,包括挥发性有机物(VOCs)和半挥发性有机物(SVOCs),其中半挥发性有机物的类别较多,有硝基苯、氯苯、苯胺、苯酚、有机氯农药、有机磷农药、多环芳烃和多氯联苯等有机污染物,分析方法以气相色谱为主.……

绿色单峰发光聚(9,9-二烯丙基芴)的合成及其发光机制

为了得到绿色单峰发光的聚合物材料,我们设计并合成了9位取代的二烯丙基芴单体,在NiCl2的催化下,合成了可溶的聚芴衍生物,聚(9,9-二烯丙基芴)(PAF).较短的烯丙基链既可以增加聚芴的溶解度,双键的存在又有利于聚芴发生分子间聚集而得到绿光发射的有机电致发光器件(OLED).PAF在溶液和薄膜状态下的荧光峰分别位于403和456 nm的蓝光区域,而其器件ITO/PEDOT:PSS/PAF/LiF/Al(其中,ITO为氧化铟锡,PEDOT为聚(3,4-乙撑二氧噻吩),PSS为聚苯乙烯磺酸盐)的电致发光峰却红移至绿光区域(532 nm),得到绿色单峰发光.紫外吸收光谱、荧光发射光谱、红外光谱以及原子力显微镜(AFM)图像的结果证明,造成PAF电致发绿光的机制为聚合物分子间聚集.

用GC-MS、GC-MS-MS方法检测某些有机质成熟度参数的比较

Tm/Ts,C29甾烷ααα20S/(20S+20R)是判断原油成熟度的重要参数.所以能否准确地检测这些化合物就显得尤为关键和重要.以往我们通常采用GC-MS单极质谱来检测原油和烃原岩抽提物中饱和烃里的萜烷和甾烷成分.……

色谱-质谱分析在有机地球化学研究中的应用

色谱-质谱分析在有机地球化学领域主要用来检测地质体中的生物标志物和分子化合物.生物标志物(biomarkers)指存在地壳和大气圈中,分子结构与特定天然产物之间具有明确联系,或与特定生物类别的分子结构之间具有相关性的天然有机化合物.……

AlPO_4-5分子筛模板剂的量子化学计算

以２３种有机分子作为模板剂用于ＡｌＰＯ４－５分子筛的合成,利用分子图形技术研究这些有机分子的形状和尺寸,采用量子化学ＰＭ３方法研究这些有机分子的电子性质,计算它们与ＡｌＰＯ４－５分子筛骨架模型簇之间的相互作用能．结果表明,量子化学计算数据可以作为寻找合成ＡｌＰＯ４－５分子筛新型模板剂时的重要参考依据．

基于复杂系统理论的域间路由系统演化模型CMV-HOT

对域间路由系统的基本问题能否找到有效而又彻底的解决方法,在很大程度上取决于对域间路由系统行为模型的准确刻画.随着Internet网络规模的扩展和应用的多样化,域间路由系统体现出复杂巨系统的特征.从复杂系统理论出发,研究了Internet域间路由系统中各个自治系统在其成长消亡过程中需要考虑的各种影响因素,基于HOT理论建立了域间路由系统的动态演化模型——CMV-HOT模型.CMV-HOT模型将自治系统分为核心层AS、传输层AS以及边缘层AS三类,通过对域间路由系统的内部规律和外在表现的分析,从复杂系统的角度对域间路由系统的演化过程进行模拟.通过与真实BGP路由表数据的比较,CMV-HOT模型在节点度分布、网络的平均路径长度以及聚集系数等关键参数上有很好的一致性.因此模型能同时满足幂率特性和小世界特性,在网络研究中具有极高的准确性和实用价值.

Crystal Structure and Magnetic Property of 2-（Imidazo[1,2-α]pyri-din-2-yl）- 2-oxoacetic Acid and Its Perchlorate

We herein report two crystals based on 2-（imidazo[1,2-a]pyridin-2-yl）-2-oxoacetic acid rad- ical and its perchlorate, and investigate the relationship between magnetic properties and crystal stacking structures or supramolecular interactions. 2-（imidazo[1,2-a]pyridin-2-yl）- 2-oxoaeetic acid radical in two crystals mainly exist as diamagnetic dimer formed via short atomic contacts or supramolecular interactions （hydrogen bonds, anion-Tr or lone- pair-~r interactions）, leading to low magnetic susceptibilities. 2-（imidazo[1,2-a]pyridin-2-yl）- 2-oxoaeetic acid radical crystal exhibits quasi-one-dimensional columnar stacking chain and weak antiferromagnetism. However, its perchlorate crystal possesses one-dimensional double- stranded chain structure assembled through double hydrogen bonds and anion-To interactions, and reveals weak ferromagnetism.

Nitrogen transformation in maize soil after application of different organic manures

The nitrogen transformation in maize soil after application of different organic manure was studied. The nitrogen mineralization in surface soil, NO - 3-N dynamics and distribution in soil profile, and N 2O emission were investigated. Eight treatments were laid out randomizing with three replications in 24 plots: maize plantation without fertilizer(CK1), bare soil without maize plantation and fertilization(CK2), swine manure(S1, S2), poultry manure(P1, P2), and cattle manure(C1, C2). Three manures were applied at two application levels(15 t/hm 2 and 30 t/hm 2). The results indicated that NH + 4-N in surface soil showed the same temporal pattern without much variation among different treatments. But NO - 3-N in the same layer exhibited large temporal pattern in all treatments, which was mainly due to its easy eluviations of NO - 3-N in soil, its transformation to N 2O and the influence of precipitation. The distribution of NO - 3-N in the soil profile during maize growing season showed the leaching tendency from surface soil to subsoil, which was different among the treatments. The poultry treatments showed the largest leaching tendency. The study also revealed that the emissions of N 2O were affected by the application of organic manures in the order of P2>S2>C2>P1>S1>C1>CK1>CK2. All these results showed that organic manure applications significantly affect nitrogen transformation and distribution in maize soil. Considering N 2O emission and NO - 3-N leaching, the management of organic manure in the agriculture needs further studies.

Analysis of microstructure and performance of temper bead welded joints for SA508-3 steel by Quenching and Tempering mode

The HAZ microstructure and performance of Quenching and Tempering mode temper bead welding and general welded joints which were made on SA508-3 steel of 60 mm thickness were compared in this article. The result shows that tempering sorbite which has excellent overall performance was obtained in both modes. The microstructure of Quenching and Tempering mode welded joints got more fine grain. Even though the hardness of tempering bead welded joints is higher than the general one,it still meets the standards which is lower than 350 HV. The impact absorbing energy of each district of tempering bead welded joints HAZ reached 170 J,which is equal to general one.

城乡教师跨校交流中的匹配策略--基于“个人−组织匹配”的调查研究

教师跨校交流本质上就是教师与学校的个人−组织匹配再调整。调查发现,城乡中小学教师的个人−组织匹配总体较好,但有待提高。基于对个人−组织匹配理论的分析,结合中小学教师个人−组织匹配现状调查,本研究认为提高城乡教师跨校交流可采取如下策略:加大农村学校支持力度,提高城区交流教师与农村学校的需求−供给匹配;推行以骨干教师、优秀校长为主,普通教师为辅的交流队伍模式;提前公开交流教师与接收学校信息,尊重双方意愿,推行双向选择;重构个人−组织价值观体系,营造民主、互助、奋进的组织氛围;依托骨干教师搭建教师成长平台,提升农村学校与教师的要求−能力匹配与需求−供给匹配,实现交流教师成长与学校发展的双赢。