低能O~(3+)与H_2碰撞电子俘获过程中靶的同位素效应研究

利用全量子的分子轨道强耦合方法,我们研究了基态的O3+(2s22p2P)与氚分子和氢分子碰撞的电荷转移过程,计算了方位角为45°,能量分别为0.1eV/u,1.0eV/u,100eV/u,500eV/u的单电子俘获的振动分辨的态选择截面及总截面.分子轨道强耦合计算中采用了自旋耦合价带理论计算的三原子分子势能面和径向耦合矩阵元.对体系的电子运动同H2(T2)或H2+(T2+)的转动和振动之间的耦合,根据能量的不同,分别采用了无限阶的冲量近似或振动冲量近似.结果发现,低能O3+与H2碰撞电子俘获过程中靶的同位素效应显著:对不同的同位素靶,单电子俘获的总截面以及振动分辨态选择截面的分布明显不同;入射离子能量越低,同位素效应越显著.

17F和18Ne与质子弹性散射研究

论文讲述了采用逆运动学方法用放射性核束~(17)F和~(18)Ne与质子弹性散射的实验准备、设汁方法、实验情况、实验数据处理过程、理论分析处理和得到的结果。弹性散射测量核敞射的角分布，对位置探测器有很高的要求。在实验的准备阶段，为了对放射性核束的准确定位，研制了位置分辨为lITlm的高位团置分辨的PPAC。山于质予的穿透能力很强，在半导体硅探测器中的能损很小，实验前，刘。测量反冲质子的探测器PSSD在低能量沉积下的工作情况进行了测试，满足质f位置和I能量测量的要求。实验采用初级束流强度约为80nA能量为45Mev／A的~(20)Ne轰击lmm厚的~9Be，反应产物经过500μm厚的Wedge~(27)Al，通过次级束流线的筛选，得到~(17)F和~(18)Ne和少量的~(16)O束流，其能量分别为17.7Mev／A、16.1Mev／A和14.3Mev／A。然后轰击60μm厚的(CH_2)_n靶。用次级束流线装置的两个焦点处的塑料闪烁体测量放射性核束的时间Tl和T2，根据飞行时间差在相同的磁场条件下来鉴别粒子和得到放射性核束的能量。用靶前的两个PPAC和靶后的一个PPAC来确定放射性核束的入射方向、反应点和出射方向，反冲质子的位置由分布于各实验室系角区的五个PSSD来测定。实验数据处理时，根据放射性核束经过基本相同的飞行路径和磁场条件，用T1和T2测到的飞行时间差来确定放射性核束的能量。将入射到PPAC上的弹核粒子位置，经对宏观几何位置矫正后，来确定弹核粒子的入射方向、反应点位置和出射方向。将PSSD测量到的位置谱经与沉积能量相关的修正因子对位置修正后，确定反冲核在PSSD上的几何位置点，跟PPAC测量确定的靶上的反应点位置结合，确定反冲核的出射方向。测量得到的位置经过空间关系换算，由测量到的弹核入射方向、反应点位置和反冲核出射方向，得到弹性散射的实验室系散射角。累计所有测到的事件得到初始的反冲核实验测量角分布。采用逐个事件的方法，用一事先产生的一系列点组成的数据库模拟探测器边界，事件的几何探测效率进行归一化，得到实际的实验室系散射角分布。用弹核出射角度随反冲核的出射角度的运动学关系鉴别来自靶中的H和C的散射事件。将实验室系角分布转换到质心系下后，再根据弹核粒子数、单位面积靶核数和测量到的事件数，得到实验测量的质的弹性散射微分截面。实验得到的微分截面数据采用零程相互作用的扭曲波玻恩近似理论计算程序DWUCK4序进行光学势拟合计算，选用较准确描述奇异核性质的CH89参数化的光学势为初始的光学势参数，对光学势参数的组成成分进行敏感性分析后，确定参数搜索的顺序，用跟各参数相关联的自动参数搜索程序ABOD进行分析处理。进行光学模型的理论拟合计算时，将计算结果和实验值进行比较，拟合实验数据，求得光学势参数。参数拟合佳度用残差平方和检验(χ~2检验)。得到~(17)F和~(18)Ne与质子弹性散射的光学势参数。根据得到的光学势参数进行折叠模型分析。得到了，1)~(17)F和~(18)Ne实势相互作用均方根半径分别为，_(rF)~(1/2) = 3．239(fm)，_(r_Ne)~(1/2) = 3.317 (fm)。跟相对论平均场计算结果比较分析表明，~(17)F的核物质半径为2.95±0.03fm，~(18)Ne的核物质半径为3.07±0.03fm,~(17)F和~(18)Ne表面的密度要比相对论平均场理论预言的值要大。2)~(17)F和~(18)Ne的自旋轨道耦合相互作用主要作用于核表面区域，这是因为位于核外层的价质子的影响。

HIRFL剥离器后切束线物理设计

HIRFL is a tandem cyclotron complex for heavy ion. On the beam line between SFC and SSC, there is a stripper. Behind it, the distribution of charge states of beam is a Gauss distribution. The equilibrium charge state Q_0 is selected by 1BO2(a 50° dipole behind the stripper) and delivered to SSC. One of two new small beam line (named SLAS) after 1B02 will be builded in or der to split and deliver the unused ions of charge states (Q_0 ± n) to aspecific experimental area. Q_0 ± n ions are septumed and separated from initial(Q_0) ion beam by two septum magnets SM1, SM2. The charge state selected by SM1 will be Q_0 ± 1(6 ≤ Q_0 < 17), Q_0 ± 2(17 ≤ Q_0 < 33) and Q_0 ± 3 (Q_0 ≥ 33) forming a beam in one of the two possine new beam line with the stripping energy of (0.2 to 9.83 Mev/A), an emittance of 10π mm.mrad in the two transverse planes and an intensity ranging from 10~(11) pps for z ≤ 10 to some 10~5 pps for the heaviest element. Behind SM2, a few transport elements (three dipoles and seven qudrupoles) tra nsport Q_0 ± n beam to target positions T1, T2 (see fig. 1) and generate small beam spots (φ ≤ 4mm, φ ≤ 6mm). The optics design of the beam line has been done based on SLAC-75 (a first and second - order matrix theory). beam optics calculation has been worked out with the TRANSPORT program. The design is a very economical thinking, because without building a new accelerator we can obtain a lower energy heavy ion beam to provide for a lot of atomic and solid state physical experiments

黄土丘陵区典型植物群落根系垂直分布与环境因子的关系

深入研究植被恢复过程中根系与环境因子的响应规律,对于当前西部地区的生态环境建设中有关林草措施的配置问题具有重要理论意义和实践价值。采用对应分析(CA)和典范对应分析(CCA)方法研究黄土丘陵区4种典型植物群落的根系垂直分布特征及其与环境因子的关系。结果表明,所选群落的根系生物量随土层深度增加而明显减小,0~40 cm土层根系生物量超过总根量的85%。借助CA分析将根系的垂直分布特征分为T1、T2和T3,其中大多数群落属于T1型,即表层根量聚积型,0~20 cm土层根量远高于其他层次;T2和T3型为深根与浅根型根系的组合类型,层次变化相对缓和。群落根系的垂直分布及变化受环境因子的综合影响,T1型分布在硝态氮含量较高且有机质和全氮含量较低的地段;T2和T3型的有机质和全氮含量较高,硝态氮含量较低;土壤水分含量、密度、硝态氮是影响退耕地典型植物群落根系垂直分布特征的主要环境因子。

气候变暖对高寒草甸气候生产潜力的影响

利用多年定位测定的草地生产力资料及同步气象因素观测数据, 建立现实状况下光、温、水影响草地气候生产潜力模型: 　　Y= F1 (Q ) ·F2 (T ) ·F3 (P) 　　 = K ∑[(-b·exp (a+ b∑t/∑tmax) )/(1+ exp (a+ b∑t/∑tmax) )2 ] 0　　　　　　　　　　　T < 0℃ ·[W 0/∑tmax ]·△∑t· Tö2 0·016658　　　0℃≤T< 20℃ 1　　　　　　　　　　　T ≥20℃ 在分析现实高寒草旬气候生产力分布与环境条件关系的同时, 根据该模型模拟计算未来气温升高2℃和4℃, 降水增加10% 和20% 状况下的气候生产力情景。在上述两种气候情景下, 未来草地生产力分别出现降低(10% ) 和升高(1% ) 的两种可能。气候变暖在一定程度上减少和缓和低温对高寒草甸牧草生长的不利影响, 但地表及植被的蒸散量的加大远比降水增加的快, 水分则成为牧草生长的限制因素。

四川盆地构造控藏规律研究

Firstly, established sequence stratigraphy of Sinian System-Middle Triassic Series framework in Sichuan basin,be divided into 21 second-level sequence stratigraphy and 105 third-level sequence stratigraphy.From many aspects,discussed sequence stratigraphy characteristic. On the foundation of structure unconformity and fission track analysis, on the ground of An county-Shuinin county regional seismic section, using the positive evolution equilibrium principle technology, comprehensivly be mapped structure evolution of Sichuan basin. It can be divided into seven stages, that is :Pre-Sinian basement stage, cratonic depression basin(Z1-S)stage, cratonic rifted basin(D-T2)stage, passive continental margin(T3x1-3)stage, foreland basin(T3x4-6)stage, depression basin (Jurassic Period-Miocene Epoch) stage, formed basin (Holocene Epoch) stage. Analysis on structure evolution history,burial history,source rocks thermal evolution history, Maoba changxing formation gas pool forming process can be classified into four stages: ancient lithological oil pool stages in Indosinian-early Yanshanian period（T-J1-2）, ancient structure- lithological gas pool stages in middle Yanshanian period（J3-K1）, structure- lithological gas pool setting stages in last Yanshanian period（K2）, structure- lithological gas pool adjusting and transformation stages in Himalayan period（R-Q）. Maoba feixianguan formation gas pool forming process can be classified into two stages: second structure gas pool stages in last Yanshanian period（K2）,second structure gas pool physical adjusting and transformation stages in Himalayan period（R-Q）,and summarize reservoir formation model. On the base of newest exploration achievement and petroleum geologic comprehensive research , demonstrate how structure controls hydrocarbon accumulation. Structure controlling source rocks behaves structure controlling main source rocks’sedimentary facies, medium-large pools mainly located at center or margin of hydrocarbon generation. Structure controlling palaeo-karst reservoirs ,reef and beach facies reservoirs, fault and fracture reservoirs. Structure controlling palaeo-uplift, and palaeo-uplift controlling hydrocarbon migration, active reservoirs’forming, palaeo-structure traps forming. Structure controls distribution of mudstone and gypsolith, controls preservation. Structure controls hydrocarbon conducting, structure traps forming and hydrocarbon accumulation. Whether or no, Structure controls total process of basin forming-source rocks’generation- hydrocarbon accumulation. It is direct effect results of structure movements that large traps’ conditions, conducting migration conditions, high quality preservation. source rocks’condition and reservoirs’ condition are the indirect effect results. In the last analysis, “source rock controlling theory”, “high quality reservoir mainly controlling theory”, “palaeo-uplift controlling theory” and “current structure deciding theory” are structure controlling hydrocarbon accumulation. There are high variability and complex mechanisms in Sichuan basin , but the regional hydrocarbon accumulation conditions are very well, such as abundant source rocks, matching process of hydrocarbon accumulation and many exploration areas. By means of integrated analysis, put forward hydrocarbon exploration direction and large-middle targets of China Petroleum and Chemical Corporation .Thus, more and more hydrocarbon proved reserve and output in Sichuan basin will be contributed to China energy industry in a long future time.

下扬子北缘前陆盆地形成演化与油气赋存条件

The foreland basin on the northern margin of the lower reach of the Yangtze river (the lower Yangtze foreland basin) is tectonically situated in the basin-mountain transitional area along the southeastern flank of the Dabie mountains. The early formation and development of the basin is closely related to the open-up of the Mian-Lue paleo-oceanic basin on the southern margin of the Central Orogenic System represented by Qinling-Dabei orogenic belt, while the tectonic evolution of the middle-late stage of the basin is mainly related to development of the Mian-Lue tectonic zone that occurred on the basis of the previous Mian-Lue paleo-suture. The foreland basin of the northern rim of the lower reach of the Yangtze river was formed during the middle-Triassic collision between the Yangtze and North China plates and experienced an evolution of occuirence-development-extinction characterized by marine facies to continental facies and continental margin to intracontinent in terms of tectonic setting.The foreland basin (T2-J2) was developed on the basis of the passive continental marginal basin on the south side of the Mian-Lue paleo-ocean and superimposed by late Jurassic-Tertiary fault basin. The tectonic setting underwent a multiple transformation of rifting-collisional clososing-tensional faulting and depression, which resulted in changes of the property for the basin and the final formation of the superposed compose basin in a fashion of 3-story-building. According to the tectonic position and evolution stages of plate collision happening on the southeastern margin of the Dabie mountains, and tectono-tratigraphic features shown by the foreland basin in its main formational period, the evolution of the foreland basin can be divided into four stages: 1) pre-orogenic passive margin (P2-Ti). As the Mian-Lue ocean commenced subduction in the late-Permian, the approaching of the Yangtze and North China plates to each other led to long-periodical and large-scale marine regression in early Triassic which was 22 Ma earlier than the global one and generated I-type mixed strata of the clastic rocks and carbonate, and I-type carbonate platform. These represent the passive stratigraphy formed before formation of the foreland basin. 2) Foreland basin on continental margin during main orogenic episode (T2.3). The stage includes the sub-stage of marine foreland basin (T2X remain basin), which formed I-type stratigrphy of carbonate tidal flat-lagoon, the sub-stage of marine-continental transition-molasse showing II-type stratigraphy of marine-continental facies lake - continental facies lake. 3) Intracontinental foreland basin during intracontinental orogeny (Ji-2)- It is characterized by continental facies coal-bearing molasses. 4) Tensional fault and depression during post-orogeny (J3-E). It formed tectono-stratigraphy post formation of the foreland basin, marking the end of the foreland evolution. Fold-thrust deformation of the lower Yangtze foreland basin mainly happened in late middle-Jurassic, forming ramp structures along the Yangtze river that display thrusting, with deformation strength weakening toward the river from both the Dabie mountains and the Jiangnan rise. This exhibits as three zones in a pattern of thick-skinned structure involved the basement of the orogenic belt to decollement thin-skinned structure of fold-thrust from north to south: thrust zone of foreland basin on northern rim of the lower reach of the Yangtze river, foreland basin zone and Jiannan compose uplift zone. Due to the superposed tensional deformation on the earlier compressional deformation, the structural geometric stratification has occurred vertically: the upper part exhibits late tensional deformation, the middle portion is characterized by ramp fault -fold deformation on the base of the Silurian decollement and weak deformation in the lower portion consisting of Silurian and Neo-Proterozoic separated by the two decollements. These portions constitutes a three-layered structural assemblage in a 3-D geometric model.From the succession of the lower reach of the Yangtze river and combined with characteristics of hydrocarbon-bearing rocks and oil-gas system, it can be seen that the succession of the continental facies foreland basin overlies the marine facies stratigraphy on the passive continental margin, which formed upper continental facies and lower marine facies hydrocarbon-bearing rock system and oil-gas forming system possessing the basic conditions for oil-gas occurrence. Among the conditions, the key for oil-gas accumulation is development and preservation of the marine hydrocarbon-bearing rocks underlying the foreland basin. The synthetic study that in the lower Yangtze foreland basin (including the Wangjiang-Qianshan basin), the generation-reservoir-cover association with the Permian marine facies hydrocarbon-bearing rocks as the critical portion can be a prospective oil-gas accumulation.Therefore, it should aim at the upper Paleozoic marine hydrocarbon-bearing rock system and oil-gas forming system in oil-gas evaluation and exploration. Also, fining excellent reservoir phase and well-preserved oil-gas accumulation units is extremely important for a breakthrough in oil-gas exploration.

江西大吉山钨矿成矿年代学研究

大吉山钨矿床是一个大型的石英脉型钨矿床。矿床在空间上与燕山早期复式花岗岩相伴。利用云母单矿物的X·Ar同位素年龄测试方法，测定了矿床有关的花岗岩及矿脉的同位素年龄。结果表明，黑云母花岗岩中黑云母X．Ar年龄为(160．3t3．00)Ma和(164．2士3．5)Ma，二云母花岗岩中白云母X．Ar年龄为(160．6t2．8)Ma，含钨石英脉中白云母K-Ar年龄为(152．6t2．35)Ma和(158．!t2．8)Ma0钨成矿与花岗岩的成岩基本不存在时差，推测含钨石英脉的形成可能与岩浆分异出的富含矿化剂和成矿元素的流体有关。

长江中下游湖泊的环境演化：沉积物的碳、氮同位素记录研究

本项研究以长江中下游地区的浅水湖泊（太湖、巢湖、龙感湖）为研究对象，碳、氮同位素为研究手段，结合210Pb和14C年代学，以及沉积物中TOC、TN、C/N比值、TP等多种地球化学参数，对近代沉积环境演化过程，沉积物有机质来源以及西太湖形成演化的古环境进行分析研究。通过研究，得到以下主要认识： 1. 太湖沉积物剖面上δ13Corg和C/N比值分布范围指示太湖沉积物的有机物质来源主要是水生藻类。竺山湾T3点基本没有陆源物质输入；梅梁湾T2点有部分陆源物质输入；湖心T4点沉积物有机质来源还可能是不同于梅梁湾和竺山湾的水生植物。沉积物的地球化学参数剖面指示太湖从1920s始，沉积环境受人为因素的影响而逐渐营养化。 2. 巢湖沉积物δ13Corg和δ15N的研究结果，不仅指示沉积物有机质来源主要是水生藻类，受城市污染和农业面源污染输入的一定影响，而且指示了在沉积历史上因为巢湖闸的建成，湖泊生产力和浮游植物物种也发生了改变，湖泊富营养化。 3. 龙感湖沉积物δ13Corg和δ15N的研究分析，表明湖泊有机沉积以自身有机物源为主，受陆源输入影响小。1960s围垦造成营养盐输入量的增加，因为草型湖泊这一特征有利于营养盐的积累，缓解水体的富营养化程度，龙感湖始终处于中营养程度。 4. 太湖、巢湖和龙感湖表层沉积物孔隙水中NO3－和SO42-含量的差异，主要受水域污染状况、底泥有机质的丰富情况、环境水动力条件的变化、泥沙沉积和再悬浮过程引起的元素累积和释放影响，也是藻型湖泊与草型湖泊生产力大小、有机质沉积通量以及微生物丰度和活性等差异的表征。 5. 沉积物表层吸附态NH4+-N含量，体现了水域环境受污染的严重程度是：龙感湖<巢湖<太湖梅梁湾。三个湖泊中底泥有机质丰度差异和生物参与的氨化作用差别都非常显著。三个湖泊的沉积物表层铵态氮的含量，均表明了沉积物表层向上覆水体可能具有潜在的铵态氮迁移趋势。 6. 太湖古环境分析研究中，竺山湾和梅梁湾沉积物剖面的粒度分析、δ13Corg、δ15N、TOC、TN、C/N比值和TP都随沉积深度，对应14C定年结果，指示了西太湖沉积演化历程的三个阶段及其有机质来源。6870~6670 a B.P.，研究区被咸水覆盖，有机质来源是典型的水体自生来源，在竺山湾有逐渐增加的C4植物的输入。6670~5140 a B.P.，可能形成瀉湖并出现沉积间断。5140 a B.P.至今，形成淡水湖泊，沉积有机质主要来自湖泊自生物源，存在沉积间断。 7. 长江中下游的浅水湖泊沉积物中的有机质来源主要以湖泊自生来源为主，因为水体初级生产力的升高受陆源物质输入增加的影响，流域内人类活动引起的陆源物质输入不容忽视。长江中下游湖泊的近代沉积环境演化过程因为近岸距离、水动力强度和发育不同的水生植物等因素存在区域性差异，导致湖泊富营养化的最大根源是人为因素的影响发生的环境演变。

兰坪盆地演化与多金属大型矿集区形成耦合关系研究

滇西兰坪中新生代盆地是我国著名“三江”构造带的重要组成部分，盆地内矿产资源丰富，金顶超大型铅锌多金属矿床及其周围的铜多金属矿床构成了我国西南地区重要的多金属大型矿集区之一。本文重点研究了兰坪中新生代盆地的演化、矿集区的成矿作用以及盆地演化与矿集区形成的藕合关系；同时对盆地上三叠统三合洞组的沉积环境以及盆地沉积岩源区构造背景和物源属性也进行了分析。研究结果表明：上三叠统三合洞组的沉积环境属浅海局限台地相，沉积时古海水的温度介于26.7℃-32.1℃，反映上三叠统三合洞组沉积时兰坪盆地处于炎热的热带区；盆地沉积岩源区构造属被动大陆边缘环境和大陆岛弧环境，原始物源来自上地壳，以长英质岩石为主，兰坪中新生代盆地属典型的大陆型盆地；盆地演化经历了三个原型盆地即裂陷盆地（T2-J1）、坳陷盆地（J2-K1）和走滑盆地（E-N）的演化过程，三个原型盆地的形成和演化明显受特提斯洋演化和印度板块与欧亚板块碰撞作用的制约；矿集：区内矿床的成矿物质源自地壳（盆地基底和盆地地层）、成矿流体为盆地热卤水：沥自盆地生油岩地层的有机质参与了成矿作用；矿集区矿床形成时间为56Ma左右或3OMa左右，两时间分别与印度板块和欧亚板块发生碰撞和后续的强烈挤压阶段的时间相一致；中新生代兰坪盆地演化过程也是多金属大型矿集区形成的过程。在裂陷和坳陷盆地演化阶段是大型矿集区形成的预备阶段，形成了成矿物质、成矿流体和成矿流．体通道及矿石堆积场所；走滑盆地演化过程中，强烈的构造活动等使区内成矿能量快速积聚，同时进一步富集成矿物质、成矿流体进一步汇聚以及形成成矿流体的运移通道和矿石堆积的场所，在印度板块和欧亚板块发生碰撞时和后续的强烈挤压阶段分别发生成矿作用，最后形成多金属大型矿集区。

Morfometria da cabeça espermática em touros Nelore submetidos a deficiência de zinco na dieta.

Touros jovens da raça Nelore (n=6) foram mantidos em pasto formado de Brachiaria brizantha desde a desmama em dietas com diferentes níveis de zinco. Foram formados aleatoriamente dois grupos que receberam diariamente, durante dois anos, diferentes concentrações de zinco no sal mineral: T1 (n=4), os animais não receberam suplemento com zinco e T2 (n=2), 60 mg/kg/dia de Zn inorgânico suplementar. A concentração de Zn na pastagem variou de 17,8 (águas) a 12,8 mg/kg (seca), respectivamente. A partir dos 14 meses de idade, os animais foram submetidos quinzenalmente a exame de sêmen e colheita de sangue. A morfologia espermática foi estimada, incluindo a mensuração da cabeça espermática a partir de esfregaços coradas pelo método de Fuelgen, em imagens captadas digitalmente e processadas pelo software Kontron Eletronik Imaging System, KS 400-2.0. A concentração de zinco no plasma foi dosada por spectrofotometria de absorção atômica. Os resultados mostraram que os touros do T1 tiveram qualidade seminal inferior (P<0,05) em relação ao T2. Observou-se variação das características seminais em função da data da colheita, evidenciando efeito estacional sobre a qualidade do sêmen. Os defeitos mais encontrados foram de peça intermediária e cauda. A concentração de Zinco (Zn) na circulação sangüínea foi maior (P<0,01) no T1 em comparação ao T2 (0,72 ±0,01 x 0,66 ±0,01, respectivamente). A área da cabeça espermática de espermatozóides morfologicamente normais e com defeitos de cabeça, peça intermediária e cauda foi maior (P<0,01) para os touros do T1 em relação aos do T2. Ademais, espermatozóides com fragmentação nuclear apresentaram forma mais alongada quando comparados àqueles sem alterações morfológicas. As correlações encontradas sugerem a importância do Zn na qualidade seminal, especialmente pelos efeitos deletérios que sua deficiência (subclínica) causa na morfologia espermática.

Características agronômicas de bananeira Terra, cv. D'Angola, em consórcio com açaizeiro (Euterpe precatoria Mart.).

O sistema de cultivo em consórcio de fruteiras com outras culturas, sejam anuais, semiperenes ou perenes, constitui uma boa alternativa para propriedades rurais e uma importante forma de recuperação de áreas degradadas. O objetivo deste trabalho foi avaliar o comportamento de bananeira, cv. D'Angola, em monocultivo e consorciada com açaizeiro, Euterpe precatoria, em diferentes espaçamentos, no primeiro ciclo de produção. Para tanto, foi instalado um experimento seguindo um delineamento em blocos casualizados completos com quatro repetições e seis plantas por parcela. Os tratamentos foram: T1 ? bananeira em 3 m x 3 m (1.111 plantas ha-1); T2 ? bananeira em 3 m x 2 m (1.666 plantas ha-1) com açaizeiro em 3 m x 4 m (833 plantas ha-1); T3 ? bananeira em 3 m x 3 m (1.111 plantas ha-1) com açaizeiro em 3 m x 4 m (833 plantas ha-1); T4 ? bananeira em 4 m x 2 m x 2 m (1.666 plantas ha-1) com açaizeiro em 6 m x 3 m (555 plantas ha-1) e T5 ? bananeira em 4 m x 2 m x 2 m (1.666 plantas ha-1) com açaizeiro em 4 m x 2 m x 3 m (1.111 plantas ha-1). O sistema de cultivo da bananeira terra consorciada com açaizeiro em diferentes espaçamentos pode ser considerado como boa alternativa no primeiro ciclo, pois não apresentou interferência nas características de desenvolvimento, de produção e qualidade física dos frutos. Os plantios mais adensados propiciaram maiores produtividades no primeiro ciclo da cultura.

PROTRACTED HYPOFRACTIONATED RADIOTHERAPY for GRAVES' OPHTHALMOPATHY: A PILOT STUDY of CLINICAL and RADIOLOGIC RESPONSE

Purpose: To evaluate the clinical and radiologic response of patients with Graves' ophthalmopathy given low-dose orbital radiotherapy (RT) with a protracted fractionation.Methods and Materials: Eighteen patients (36 orbits) received orbital RT with a total dose of 10 Gy, fractionated in 1 Gy once a week over 10 weeks. of these, 9 patients received steroid therapy as well. Patients were evaluated clinically and radiologically at 6 months after treatment. Clinical response assessment was carried out using three criteria: by physical examination, by a modified clinical activity score, and by a verbal questionnaire considering the 10 most common signs and symptoms of the disease. Radiologic response was assessed by magnetic resonance imaging.Results: Improvement in ocular pain, palpebral edema, visual acuity, and ocular motility was observed in all patients. Significant decrease in symptoms such as tearing (p < 0.001) diplopia (p = 0.008), conjunctival hyperemia (p = 0.002), and ocular grittiness (p = 0.031) also occurred. Magnetic resonance imaging showed decrease in ocular muscle thickness and in the intensity of the T2 sequence signal in the majority of patients. Treatments were well tolerated, and to date no complications from treatment have been observed. There was no statistical difference in clinical and radiologic response between patients receiving RT alone and those receiving RT plus steroid therapy.Conclusion: RT delivered in at a low dose and in a protracted scheme should be considered as a useful therapeutic option for patients with Graves' ophthalmopathy. (C) 2012 Elsevier Inc.

Body composition and bone mineral density changes during a premier league season as measured by dual-energy X-ray absorptiometry

Wallace, Joanne, et al., 'Body composition and bone mineral density changes during a premier league season as measured by dual-energy X-ray absorptiometry', International Journal of Body Composition Research (2006) 4(2) pp.61-66 RAE2008

On the Origin of Power Laws in Internet Topologies

Recent empirical studies have shown that Internet topologies exhibit power laws of the form for the following relationships: (P1) outdegree of node (domain or router) versus rank; (P2) number of nodes versus outdegree; (P3) number of node pairs y = x^α within a neighborhood versus neighborhood size (in hops); and (P4) eigenvalues of the adjacency matrix versus rank. However, causes for the appearance of such power laws have not been convincingly given. In this paper, we examine four factors in the formation of Internet topologies. These factors are (F1) preferential connectivity of a new node to existing nodes; (F2) incremental growth of the network; (F3) distribution of nodes in space; and (F4) locality of edge connections. In synthetically generated network topologies, we study the relevance of each factor in causing the aforementioned power laws as well as other properties, namely diameter, average path length and clustering coefficient. Different kinds of network topologies are generated: (T1) topologies generated using our parametrized generator, we call BRITE; (T2) random topologies generated using the well-known Waxman model; (T3) Transit-Stub topologies generated using GT-ITM tool; and (T4) regular grid topologies. We observe that some generated topologies may not obey power laws P1 and P2. Thus, the existence of these power laws can be used to validate the accuracy of a given tool in generating representative Internet topologies. Power laws P3 and P4 were observed in nearly all considered topologies, but different topologies showed different values of the power exponent α. Thus, while the presence of power laws P3 and P4 do not give strong evidence for the representativeness of a generated topology, the value of α in P3 and P4 can be used as a litmus test for the representativeness of a generated topology. We also find that factors F1 and F2 are the key contributors in our study which provide the resemblance of our generated topologies to that of the Internet.