Optimal state filtering and parameter identification for linear systems

This paper presents the optimal filtering and parameter identification problem for linear stochastic systems with unknown multiplicative and additive parameters over linear observations, where unknown parameters are considered Wiener processes. The original problem is reduced to the filtering problem for an extended state vector that incorporates parameters as additional states. The obtained optimal filter for the extended state vector also serves as the optimal identifier for the unknown parameters. Performance of the designed optimal state filter and parameter identifier is verified for both stable and unstable linear uncertain systems. Copyright © 2007 John Wiley & Sons, Ltd.     

Direct optimization of dynamic systems described by differential‐algebraic equations

This paper presents a method for the optimization of dynamic systems described by index‐1 differential‐algebraic equations (DAE). The class of problems addressed include optimal control problems and parameter identification problems. Here, the controls are parameterized using piecewise constant inputs on a grid in the time interval of interest. In addition, the DAE are approximated using a Rosenbrock–Wanner (ROW) method. In this way the infinite‐dimensional optimal control problem is transformed into a finite‐dimensional nonlinear programming problem (NLP). The NLP is solved using a sequential quadratic programming (QP) technique that minimizes the L_∞ exact penalty function, using only strictly convex QP subproblems. This paper shows that the ROW method discretization of the DAE leads to (i) a relatively small NLP problem and (ii) an efficient technique for evaluating the function, constraints and gradients associated with the NLP problem. This paper also investigates a state mesh refinement technique that ensures a sufficiently accurate representation of the optimal state trajectory. Two nontrivial examples are used to illustrate the effectiveness of the proposed method. Copyright © 2008 John Wiley & Sons, Ltd.     

护理本、专科毕业生就业核心竞争力识别模型研究

目的明确护理本、专科毕业生就业的核心竞争力,为护理院校进行有针对性的就业竞争力培训提供依据。方法运用调查研究法、文献查阅法、专家访谈法建立护理本、专科毕业生就业核心竞争力测试量表,并对228名护士进行调查;根据人力资源管理理论及核心竞争力理论,应用模型量表各维度建立护理本、专科毕业生就业核心竞争力识别模型,将各要素的竞争强度以点的形式标于核心竞争力识别模型上。结果该模型包括专业力、意志力、思维力、凝聚力等8个维度及从业稳定性,量表总体Cronbach’sq系数为0．955,各维度Cronbach’s a系数均〉0．7;专业力、思维力、创造力、可持续发展力是护理本科生就业的核心竞争力,意志力、凝聚力、执行力、从事护理专业的稳定性是护理专科生就业的核心竞争力。结论识别模型量表具有较好的信度和效度,据此建立的识别模型可以客观地评价不同学历护理专业学生的就业核心竞争力,可作为教学的参考。     

利用shotgun蛋白组学策略鉴定健康生育男性精浆蛋白质

目的:鉴定正常生育男性的精浆蛋白质。方法:3例正常健康已生育的自愿者精液标本通过Percoll分离获取精浆,等量混合后在SDS-PAGE上进行分离,切胶取条带进行胶内酶解,抽提肽段后利用shotgun蛋白组学策略鉴定蛋白质。结果:正常生育男性精浆鉴定出331种蛋白质,相对分子质量范围8000～572068,等电点范围4.36～11.05;这些蛋白质按功能和生物进程归类,大致有51个(15.4%)运输蛋白质,11个(3.32%)细胞运动蛋白,63个(19.03%)信号转导蛋白质,147个(44.4%)蛋白酶及38个(11.5%)酶调节蛋白质,21个(6.3%)细胞凋亡蛋白,12个(3.62%)结构和支撑蛋白质,59个(17.8%)分子功能未知蛋白质。结论:shotgun蛋白组学策略是鉴定蛋白质的一个较好的方法。膜联蛋白及相关蛋白、Ras相关蛋白Rab是鉴定到的信号转导蛋白中的主要成员,因此推测钙离子和G蛋白信号通路是精子胞外信号传递到胞内的最重要途径,但是这些蛋白间的相互作用还不清楚。另外,精浆中鉴定到了大量的酶类,可能与维持精子活力和代谢有密切关系。     

大鼠骨髓间充质干细胞的体外分离培养与鉴定

目的 体外观察大鼠骨髓间充质干细胞的基本生物学特性,建立rMSCs的分离培养方法,为诱导分化成肌研究打下基础.方法 采用Percoll密度梯度离心法分离纯化大鼠MSCs.观察细胞的形态和生长特性,倍增时间,生长曲线,用流式细胞仪分析rMSCs的表面抗原.结果 体外培养的rMSCs很快贴壁.4～8d即贴壁80%,细胞增殖迅速,7d左右即可达到80%融合.流式细胞仪分析CD90、CD13、CD44表达强阳性,CD14、CD34、CD45和HLA-DR表达阴性,符合MSCs的表面抗原特征.结论 经Percoll密度梯度离心法获得的rMSCs细胞株较纯,可作为组织工程中的种子细胞来源,但大鼠MSCs在体外培养过程中易于衰老.     

脊柱孤立性浆细胞瘤的临床及影像学特点分析

目的：探讨脊柱孤立性浆细胞瘤的临床及影像学特点。方法：分析经手术病理检查证实的6例脊柱孤立性浆细胞瘤病例的临床特点及影像学特征。结果：病椎附近逐渐加重的疼痛是其共同首发临床表现。其X线片多表现为椎体的溶骨性破坏；ECT上表现不一；CT多为椎体骨质的虫嗜状破坏；MRI示病椎信号失均，T1WI低信号，T2WI等或稍高信号，增强扫描有不均匀强化。结论：CT及MRI可明确脊柱孤立性浆细胞瘤的形态特征及病灶范围，其确诊仍需借助骨髓活检或手术标本病理检查。但对颈背部疼痛的患者，早期行MRI检查有助于及时发现病变，避免严重脊柱脊髓损害的出现。     

Utilidad de la fluorescencia cercana al infrarrojo para la identificación del bronquio segmentario en segmentectomías mínimamente invasivas

Minimally invasive anatomical sublobar resections have gained relevance in recent years mainly due to advances in imaging techniques, screening programs and the increase in second neoplasms. Accurate identification of the segmental or subsegmental bronchus is vital to guarantee optimal results in segmentectomies and subsegmentectomies. Given the complexity and the possibility of anatomical variations, several authors have published different methods to identify the target bronchus. However, these methods have certain limitations. This article describes a new rapid and effective technique, with a low risk of complications and without additional cost, for the identification of segmental bronchi in minimally invasive segmentectomies.     

金疮小草与广藿香的比较鉴别研究

【目的】为区分金疮小草(Ajuga decumbens Thunb.)与广藿香[Pogostemon cablin(Blanco.)Benth.]提供参考依据。【方法】采集金疮小草、广藿香2种植物的新鲜茎和叶作为样品,采用体视镜进行原植物外观形态鉴别,采用显微镜对2种植物茎横切面、叶柄横切面、叶表皮以及粉末进行显微鉴别。【结果】原植物外观形态鉴别:金疮小草叶柄有狭翅,广藿香无;金疮小草叶主脉与侧脉夹角小于45°,广藿香大于45°。显微鉴别:金疮小草腺鳞头部细胞数为多细胞,而广藿香为单细胞;广藿香茎和叶有间隙腺毛、晶体,金疮小草无。金疮小草有直轴式和不定式气孔,广藿香只有直轴式。【结论】金疮小草与广藿香外观形态特征及显微特征可作为区分鉴别2种植物的参考依据。     

不同基原土牛膝的性状显微比较研究

目的 建立3种不同基原的土牛膝的性状及显微鉴别方法。方法 在植物分类学鉴定基础上,对不同基原的土牛膝进行鉴定,并使用性状和显微研究方法,对采集的土牛膝进行比较分析。结果 通过研究发现,3种土牛膝可以通过横切面显微特征区分,粉末显微特征区别不明显。结论 土牛膝不同基原可以通过性状、显微进行鉴别,通过对二者性状、显微的细致研究,为相关的标准修订与提高提供依据。