磁性纳米微粒的制备及其在磁性靶向药物转运中的应用

以磁性纳米微粒为靶向药物的载体,可以将药物选择性地靶向肿瘤病灶,有效地降低其对正常组织的毒副作用,提高药物的疗效,是一种新型的药物投递系统.本文综述了磁性纳米微粒的制备方法及其在磁性靶向药物传递中作为药物载体的应用研究进展.     

Optimal filters for the detection of linear patterns in 2-D and higher dimensional images

It is shown that the rotation-invariant operators form a set of orthogonal basis functions which is optimal for a wide range of 2-D and 3-D feature-detection operations. The optimality criterion used is based on the Karhunen-Loève expansion of the local image data. This is a generalization of the work of Zucker and Hummel who showed that these filters are optimal filters for the detection of step edges in 2-D and 3-D images.     

基于微生物分型的归因方法对我国归因研究的启示

食源性疾病是全球重要的公共卫生问题,尤其以微生物危害因素中致病菌导致的危害最为严重,在基于风险的食品安全管理体系下,识别优先管控的危害因素极其重要的食物来源是防控食源性疾病的前提和关键。结合微生物分型和统计建模的归因方法是国际通用的以确定不同食物来源对食源性疾病相对贡献的技术方法,目前欧美等国已经建立了频率匹配和群体遗传学两大类基于微生物分型的归因方法模型,并将其结果转化为食品安全风险管控措施制定的科学依据,而我国目前正处于食源性疾病归因方法研究的初步探索阶段。本文系统梳理了目前国际广泛应用的归因方法的方法原理和模型,结合我国食源性疾病归因研究基础和现状,提出“建方法、合数据、搭平台、强交流”四个我国下阶段食源性疾病归因体系建设的工作方向,其中研发本土化微生物分型归因模型方法是解决我国确证管控核心和防控我国食源性疾病面临的挑战,最终实现食品安全和保障人民生命健康。     

Do you believe in the advantage of expert systems in industrial ergonomics?

Reasons for reservations about accepting the recommendations of industrial ergonomics are first explored. A knowledge deficiency is ascertained which results in a general dependency on ergonomic experts. The experts, however, are rarely able to communicate their knowledge in a form applicable by a practitioner. The development and employment of expert systems suitable for use in work design problems are proposed to resolve this dilemma. The question of whether an interest in expert systems for industrial ergonomics can be assumed is considered. The necessary conditions for the successful development and introduction of expert systems for industrial ergonomics are derived. The extent to which currently available expert system technology can support the typical procedures in industrial ergonomics is subsequently examined.     

HACCP在牛肉香味粉加工中应用研究

对食品配料企业的牛肉香味粉加工工艺进行了研究,确定了牛肉香味粉的关键控制点,改进了产品的加工工艺,提高了产品的质量。     

Structural,optical and temperature dependent photoluminescence properties of Cr3+-activated LaGaO3 persistent phosphor for optical thermometry

Cr³⁺ doped LaGaO₃ phosphor was prepared by hydrothermal reaction method with post-annealing treatment. XRD pattern showed the pure orthorhombic phase of LaGaO₃ at an annealing temperature of 1000 °C. TEM image showed the particles in the range 40-120 nm. The bandgap energy and Urbach tail increased in the doped sample as compared to the undoped sample as estimated from UV–visible diffuse reflectance spectra. PL excitation spectra showed peaks in UV, blue and orange regions. The emission spectra showed broadband with peaks in the NIR region due to emission from ⁴T₂ and ²E states. The intermediate strength of the crystal field has been calculated from the estimated spectroscopic parameter. The average lifetime was found to be in the ms range. Afterglow decay was also recorded. From the low-temperature PL, the zero phonon line, stokes shift energy, vibrational energy and Huang-Rhys parameter were calculated. With rising the temperature, PL emission peak intensity and lifetime values decreased and FWHM increased because of increased numbers of electrons in ⁴T₂ state and increasing non-radiative transition. Temperature-dependent peak intensity ratios and lifetime values were utilized for temperature sensing applications in below room temperature and above room temperature. The results indicate the possibility of present phosphor to be used as optical nanothermometer.     

CT引导下经皮穿刺氩氦刀靶向冷冻治疗肾癌

目的初步建立氩氦超导手术系统（简称氩氦刀）靶向冷冻治疗肾癌的技术和探讨其原理、安全性及近期疗效。方法７例肾癌患者采用氩氦刀,在CT引导下经皮穿刺对肿瘤病灶行冷冻治疗。结果７例患者冷冻治疗后未出现出血、皮肤冻伤、感染或穿刺道种植转移等严重并发症。７例在冷冻治疗后１个月,CT显示病灶区内出现低密度坏死区,５例肿瘤大小无改变,２例瘤体有不同程度缩小。结论CT引导经皮穿刺氩氦刀冷冻治疗肾癌是一种安全、有效、微创治疗,特别是对于不能行手术切除的肾癌病例。     

File space utilization in database conversion

File space is an important type of resource needed during the process of converting data base from one form to another. Each file used in the conversion process has a size and life span. The life span of a file is measured from its creation time until the time it is no longer needed in the conversion process. The problem considered in this paper is to find a schedule for the different steps of the conversion process such that the sum of file costs is minimized. The cost of a file is defined as its life span times its size. The problem under consideration is NP-complete, and we therefore present an efficient algorithm for a special case, where the given precedence constraints are series parallel.