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关键词： 柱形量子线   极化子   基态能量   温度  

摘要： 利用幺正变换和变分法研究了柱形量子线中温度对极化子性质的影响.计算了柱形量子线中极化子的基态和第一激发态能量.数值计算结果表明,当温度参数γ>1,即kBT<ωLO时,极化子基态和第一激发态能量不随温度的变化而变化;当0<γ<1,即kBT>ωLO时,基态和第一激发态能量随温度的升高而增加.而当温度一定时,基态和第一激发态能量随半径的增大而减小,说明了柱形量子线具有明显的量子尺寸效应.

摘要： Optical emission from atoms with radioactive nuclei is investigated. The self energy function of the unstable nucleus is constructed. A new arbitrary parameter characterizing the nuclear interaction is introduced. The instability of the atomic nucleus is shown to result in the essential broadening of optical emission lines. The spectral line shape is shown to be of the Lorentz form, with the width being a nonlinear combination of the nuclear and atomic decay widths multiplied by the parameter depending on the peculiarities of nuclear interaction.

关键词： Canada   immunization   influenza vaccination   pharmaceutical services   pharmacist   vaccine coverage  

摘要： Immunization coverage in Canada has continued to fall below national goals. The addition of pharmacists as immunizers may increase immunization coverage. This study aimed to compare estimated influenza vaccine coverage before and after pharmacists began administering publicly funded influenza immunizations in Nova Scotia, Canada. Vaccination coverage rates and recipient demographics for the influenza vaccination seasons 2010-2011 to 2012-2013 were compared with the 2013-2014 season, the first year pharmacists provided immunizations. In 2013-2014, the vaccination coverage rate for those >= 5 years of age increased 6%, from 36% in 2012-2013 to 42% (p<0.001). Pharmacists administered over 78,000 influenza vaccinations, nearly 9% of the province's population over the age of five. Influenza vaccine coverage rates for those >= 65 increased by 9.8% (p<0.001) in 2013-2014 compared to 2012-2013. Influenza vaccination coverage in Nova Scotia increased in 2013-2014 compared to previous years with a universal influenza program. Various factors may have contributed to the increased coverage, including the addition of pharmacists as immunizers and media coverage of influenza related fatalities. Future research will be necessary to fully determine the impact of pharmacists as immunizers.

关键词： Myctophidae   Predation rates   Feeding ecology   Scotia Sea   Southern Ocean  

摘要： Myctophids are the most abundant mesopelagic fishes in the Southern Ocean, although their trophic role within the predominantly krill-based food web in regions south of the Antarctic Polar Front (APF) is poorly resolved. This study therefore examined the diets of 10 species of myctophid fishes: Electrona antarctica, E. carlsbergi, Gymnoscopelus braueri, G. fraseri, G. nicholsi, Krefftichthys anderssoni, Proto myctophum bolini, P. tenisoni, P. choriodon and Nannobrachium achirus, in the Scotia Sea, together with their predatory impact on the underlying zooplankton community. Myctophids and their prey were sampled in different seasons by scientific nets deployed across the Scotia Sea from the sea-ice zone to the APF. Based on the percentage index of relative importance, myctophids had high overlap in their diets, although the data indicate dietary specialisation in some species. There was also a distinct switch in diet, from copepods to euphausiids and amphipods, with increasing myctophid size. Myctophid predation impacted daily copepod production by between 0.01 and 5%, with Calanus simillimus being most impacted. Total annual consumption of copepods was around 1.5 million t (Mt) per year. All myctophids preyed upon the euphausiid Thysanoessa spp., consuming similar to 12% of its daily productivity and around 4 Mt per year. However, only larger myctophid species preyed upon Antarctic krill Euphausia superba, consuming 2% of its daily productivity, which could amount to as much as 17 Mt per year. Themisto gaudichaudii was also an important dietary component, with 4% of its daily productivity being consumed, amounting to around 2 Mt per year. This study demonstrates that myctophids link secondary productivity to higher predators both through krill-dependent and krill-independent trophic pathways.

关键词： biomechanics   finite element models   model of injury   spinal cord injury  

摘要： There are several widely used devices for controlled contusion of the spinal cord, including the Ohio State University device, the University of British Columbia multi-mechanisms injury device, the New York University (NYU) impactor, and the Infinite Horizon (IH) impactor. Although various devices and protocols have been used to generate consistent injury severities, further investigation of the relationship between the key parameters of different spinal cord injury (SCI) contusion devices (e.g., drop height in the NYU impactor and impact force in the IH impactor) will improve our understanding of SCI mechanisms. A three-dimensional finite element model of the rat spinal cord from T9 to T10 that included the white and gray matters, dura mater, and cerebrospinal fluid was developed to investigate the von-Mises stress, maximum principal strain, and maximum displacement of the spinal cord for the drop height in the NYU impactor and the impact force in the IH impactor. A quantitative relationship was established as a conversion equation between two key parametersi.e., the drop height and the impact forcein the NYU and IH impactors from regression equations for peak von-Mises stress, peak maximum principal strain, and maximum displacement in the spinal cord with respect to drop height and impact force with very high coefficients of determination. The consistent correlation was represented as a simple equation (Force=(28.2 +/- 3.2).Height((0.83 +/- 0.07))) under the experimental conditions of a 10-g rod in the NYU impactor and an impact velocity of 125mm/sec in the IH impactor. Thus, the key biomechanical parameter for a contusion device can be converted or translated to that of another device to analyze experimental results from multiple contusion devices.

摘要： Purpose: Predominant causes of head and neck cancer recurrence after radiotherapy are rapid repopulation, hypoxia, fraction of cancer stem cells, and intrinsic radioresistance. Currently, intrinsic radioresistance can only be assessed by ex vivo colony assays. Besides being time-consuming, colony assays do not identify causes of intrinsic resistance. We aimed to identify a biomarker for intrinsic radioresistance to be used before start of treatment and to reveal biologic processes that could be targeted to overcome intrinsic resistance. Experimental Design: We analyzed both microRNA and mRNA expression in a large panel of head and neck squamous cell carcinoma (HNSCC) cell lines. Expression was measured on both irradiated and unirradiated samples. Results were validated using modified cell lines and a series of patients with laryngeal cancer. Results: miRs, mRNAs, and gene sets that correlated with resistance could be identified from expression data of unirradiated cells. The presence of epithelial-to-mesenchymal transition (EMT) and low expression of miRs involved in the inhibition of EMT were important radioresistance determinants. This finding was validated in two independent cell line pairs, in which the induction of EMT reduced radiosensitivity. Moreover, low expression of the most important miR (miR-203) was shown to correlate with local disease recurrence after radiotherapy in a series of patients with laryngeal cancer. Conclusions: These findings indicate that EMT and low expression of EMT-inhibiting miRs, especially miR-203, measured in pretreatment material, causes intrinsic radioresistance of HNSCC, which could enable identification and treatment modification of radioresistant tumors. (C) 2015 AACR.

关键词： 力量   循环   游泳   影响  

摘要： 随着运动的科学化,当前游泳的纪录不断刷新跟强化体能密不可分。但是直到现在,国内大部分二线游泳队教练仍然不分运动员的主项还继续实行同一的力量训练方法,这对于长短距离不同选手是不能适用的。文章通过文献资料法、实验法等针对韩国二线游泳队12周训练后所得出的数据进行整理。结果表明:力量训练组通过增加肌肉使得无氧力量增加,进而提高了短距离运动员的成绩。而循环训练组由于提高了肌肉耐力和呼吸循环能力,在长距离的比赛中表现良好。因此,根据游泳项目的不同,要选择适当的训练方法才能有效地提高游泳成绩是非常关键的。

关键词： 地铁车站   反应位移法   抗震分析  

摘要： 以沈阳地铁某站为工程背景,选取地铁车站主体结构建立合适的有限元模型,采用反应位移法对车站结构进行地震力计算,并将静力工况下和地震力工况下的计算结果进行比较,得出地铁车站在地震力工况下的薄弱部位,以及车站结构的控制工况。

关键词： 隧道爆破   砌体结构   动力有限元   受力变形  

摘要： 为研究砌体结构物在爆破振动作用下的受力变形规律,采用动力有限元软件Midas/GTS,以安平高速公路马家梁隧道爆破施工为依托,建立三种砌体结构模型,求解出砌体结构物在爆破荷载下的峰值振动速度和应力.结果表明:三种砌体结构其最大振速为11.11mm·s-1,小于工程要求的2.8cm·s-1,其最大应力为415.082kPa,超过砌体结构的失效应力;在整个考察范围内,砌体结构的质点振动速度达到最大时,其受力没有达到最大,说明砌体结构在爆破荷载作用下的振动速度不代表其受力状态.

关键词： 物流企业   一线员工流动   影响因素  

摘要： 针对目前国内物流企业一线员工流动状况,结合相关理论研究成果,构建了物流企业一线员工流动影响因素结构模型,探讨各变量要素与一线员工流动之间的影响机理。依据理论基础提出研究假设,通过实证研究显示:薪资水平、晋升机制以及管理模式对员工满意具有显著直接正向影响效用;薪资水平、晋升机制以及员工满意对物流企业一线员工流动有直接负向影响效用,而管理模式对一线员工流动没有直接影响效用;同时薪资水平、晋升机制以及管理模式三要素可以通过员工满意对员工流动产生间接影响效用。