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．

运用董氏奇穴针灸治疗过敏性鼻结膜炎的临床应用

过敏性鼻结膜炎是临床上常见的过敏性疾病,以阵发性清涕喷嚏、流清涕、鼻塞、眼痒、流泪和眼分泌物增多为主要特征。董氏奇穴针灸是在传统针灸基础上发展起来的一种具有特色的针灸方法,具有选穴少、见效快、治疗范围广的特点,在眼科疾病的治疗中具有独特的作用。笔者在临床实践中发现,董氏奇穴对过敏性鼻结膜炎有突出的治疗作用,其治疗方法为祛风止痒、脏腑互通;配合口服汤剂,疗效显著。本文通过理论研究和临床实践,结合临床病例,总结运用董氏奇穴针灸治疗过敏性鼻结膜炎的独特经验,为该病的治疗提供新的思路和方法。

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.

Molecule-based vertical transistor via intermolecular charge transport throughπ-πstacking

Theπ-πstacking is a well-recognized intermolecular interaction that is responsible for the construction of electron hopping channels in numerous conducting frameworks/aggregates.However,the exact role ofπ-to-πchannels within typical single crystalline organic semiconductors remains unclear as the orientations of these molecules are diverse,and their control usually requires additional side chain groups that misrepresent the intrinsic properties of the original semiconducting molecules.Therefore,the construction of conduction channels with intrinsicπ-πstacking in the molecule-based device is crucial for the utilization of their unique transport characteristics and understanding of the transport mechanism.To this end,we present a molecular intercalation strategy that integrates two-dimensional layered materials with functional organic semiconductor molecules for functional molecule-based electronics.Various organic semiconductor molecules can be effectively intercalated into the van der Waals gaps of semi-metallic TaS_(2) withπ-πstacking configuration and controlled intercalant content.Our results show that the vertical charge transport in the stacking direction shows a tunneling-dominated mechanism that strongly depends on the molecular structures.Furthermore,we demonstrated a new type of molecule-based vertical transistor in which TaS_(2) andπ-πstacked organic molecules function as the electrical contact and the active channel,respectively.On/off ratios as high as 447 are achieved under electrostatic modulation in ionic liquid,comparable to the current state-of-the-art molecular transistors.Our study provides an ideal platform for probing intrinsic charge transport acrossπ-πstacked conjugated molecules and also a feasible approach for the construction of high-performance molecule-based electronic devices.

Regulating the Electron-Deficient Component in A-DA1D-A Typed Small-Molecule Acceptors for High-Performance Organic Solar Cells

Fine-tuning of the electron-deficient unit in A-DA1D-A typed small-molecule acceptors (SMAs) plays a crucial role in developing efficient SMAs for organic solar cells (OSCs).Here,we developed a SMA based on benzo[4,5]thieno[2,3-b]quinoxaline,designated as QW1,as well as three SMAs based on 1-methylindoline-2,3-dione,identified as QW2,QW3,and QW4.Compared with QW2,QW1 displays slightly blue-shifted absorption spectra and a lower LUMO energy level due to the stronger electron-withdrawing capability of BTQx in contrast to MDO.On the other hand,the introduction of a bromine atom in QW3 and QW4 causes a blue shift in absorption and a reduction in the LUMO energy level compared to QW2.Density functional theory analysis reveals that QW1 exhibits the best molecular planarity,which endows QW1 with larger electron mobility and tighter molecular stacking.Consequently,PM6:QW1 device affords a better efficiency of 15.63% than those of the devices based on QW2 (14.25%),QW3 (13.21%) and QW4 (15.03%).Moreover,the QW4-based device yields the highest open-circuit voltage of 0.933 V,and the PM6:L8-BO:QW4 ternary device realizes a PCE of 19.03%.Overall,our work demonstrates that regulation of electron-deficient central units is an effective strategy to improve the photovoltaic performance of the resulting A-DA1D-A SMAs.

Manipulating Nanowires in Interconnecting Layer for Efficient Tandem Organic Photovoltaics

Owing to the function of manipulating light absorption distribution,tandem organic solar cells containing multiple sub-cells exhibit high power conversion efficiencies.However,there is a substantial challenge in precisely controlling the inter-subcells carrier migration which determines the balance of charge transport across the entire device.The conductivity of"nanowires"-like conducting channel in interconnecting layer between sub-cells should be improved which calls for fine engineering on the morphology of polyelectrolyte in interconnecting layer.Here,we develop a simple method to effectively manipulating the domains of conductive components in commercially available polyelectrolyte PEDOT:PSs.The use of poor solvent could effectively modify the configuration of polystyrene sulfonic acid and thus the space for conductive components.Based on our strategy,the insulated shells wrapping conductive domains are thinned and the efficiencies of tandem organic solar cells are improved.We believe our method might provide guidance for the manufacture of tandem organic solar cells.