Nanostructured cochleates: a multi-layered platform for cellular transportation of therapeutics

Among lipid-based nanocarriers, multi-layered cochleates emerge as a novel delivery system because of prevention of oxidation of hydrophobic and hydrophilic drugs, enhancement in permeability, and reduction in dose of drugs. It also improves oral bioavailability and increases the safety of a drug by targeting at a specific site with less side effects. Nanostructured cochleates are used as a carrier for the delivery of water-insoluble or hydrophobic drugs of anticancer, antiviral and anti-inflammatory action. This review article focuses on different methods for preparation of cochleates, mechanism of formation of cochleates, mechanism of action like cochleate undergoes macrophagic endocytosis and release the drug into the systemic circulation by acting on membrane proteins, phospholipids, and receptors. Advanced methods such as calcium-substituted and β-cyclodextrin-based cochleates, novel techniques include microfluidic and modified trapping method. Cochleates showed enhancement in oral bioavailability of amphotericin B, delivery of factor VII, oral mucosal vaccine adjuvant-delivery system, and delivery of volatile oil. In near future, cochleate will be one of the interesting delivery systems to overcome the stability and encapsulation efficiency issues associated with liposomes. The current limiting factors for commercial preparation of cochleates involve high cost of manufacturing, lack of standardization, and specialized equipments.     

Efficient algorithms for erasure node placement on slotted dual busnetworks

We study the problem of placing erasure nodes among passive stations in a slotted dual bus network. Erasure nodes are known to improve throughput by allowing slot reuse. It is also known that choices made in locating erasure nodes significantly impact network congestion and overall throughput-especially when traffic patterns exhibit a high degree of locality. We present algorithms to determine optimal placements of erasure nodes that improve upon prior work on this problem: we present simpler and faster polynomial-time algorithms and also consider various useful cost measures. These algorithms can be used to solve related placement problems in which limits on congestion and existing placements are given as input, and the goal is to find the minimum number of erasure nodes required to meet the congestion bound     

水、丙酮混合工质振荡热管传热性能

采用水、丙酮以及其二元混合工质对振荡热管进行实验研究,选取35%～70%充液率,10～100 W加热功率以及水/丙酮13：1、4：1、1：1、1：4、1：13配比,将实验数据与混合工质物性、相变特点结合以研究其振荡热管传热性能。结果表明：混合溶液振荡热管启动所需功率小于水;小充液率时,除较低丙酮比例配比（如水/丙酮13：1混合工质）以外,混合工质比纯工质振荡热管不容易烧干,纯工质振荡热管在50 W时热阻就已经上升到较高数值,而混合工质振荡热管在同样的功率则维持着较低的热阻。在丙酮中加入少量水（如水/丙酮1：13混合工质）能有效改善振荡热管烧干情况,然而,少量丙酮与水混合而成的工质（如水/丙酮13：1混合工质）对振荡热管烧干情况的改善不明显;大充液率时,混合工质振荡热管的传热性能要弱于纯工质,在35～50 W,纯工质振荡热管热阻都低于混合工质,而在较大加热功率（50～100 W）,水与混合工质振荡热管仍保持着较明显的热阻差。对混合工质振荡热管的传热性能的分析可为今后更深入研究其工作机理以及传热特性理论模型的建立提供参考。     

An NC algorithm for recognizing tree adjoining languages

A parallel algorithm is presented for recognizing the class of languages generated by tree adjoining grammars, a tree rewriting system which has applications in natural language processing. This class of languages is known to properly include all context-free languages; for example, the noncontext-free sets {a ⁿ b ⁿ c ⁿ } and {ww} are in this class. It is shown that the recognition problem for tree adjoining languages can be solved by a concurrent read, concurrent write parallel random-access machine (CRCW PRAM) inO(logn) time using polynomially many processors. Thus, the class of tree adjoining languages is inAC ¹ and hence inNC. This extends a previous result for context-free languages.This research was supported in part by NSF Grants IRI 92-96249, MCS 82-19116-CER, MCS 82-07294, DCR 84-10413, MCS 83-05221, ARO Grant DAA29-84-9-0027, DARPA Grant N00014-85-K-0018, and by the New Jersey Institute of Technology under Grant Nos. 421690 and 211665.     

DAO数据库应用程序安装系统的设计和制作

介绍了ＤＡＯ应用程序所必需的运行库以及通用Ｉnstall Shield来制作ＤＡＯ数据库应用程序安装系统的详细方法和步骤。     

Design and Prototype of a Performance Tool Interface for OpenMP

This paper proposes a performance tools interface for OpenMP, similar in spirit to the MPI profiling interface in its intent to define a clear and portable API that makes OpenMP execution events visible to runtime performance tools. We present our design using a source-level instrumentation approach based on OpenMP directive rewriting. Rules to instrument each directive and their combination are applied to generate calls to the interface consistent with directive semantics and to pass context information (e.g., source code locations) in a portable and efficient way. Our proposed OpenMP performance API further allows user functions and arbitrary code regions to be marked and performance measurement to be controlled using new OpenMP directives. To prototype the proposed OpenMP performance interface, we have developed compatible performance libraries for the Expert automatic event trace analyzer [17, 18] and the TAU performance analysis framework [13]. The directive instrumentation transformations we define are implemented in a source-to-source translation tool called OPARI. Application examples are presented for both Expert and TAU to show the OpenMP performance interface and OPARI instrumentation tool in operation. When used together with the MPI profiling interface (as the examples also demonstrate), our proposed approach provides a portable and robust solution to performance analysis of OpenMP and mixed-mode (OpenMP+MPI) applications.     

A Characterisation of Optimal Channel Assignments for Cellular and Square Grid Wireless Networks

In this paper we first present a uniformity property that characterises optimal channel assignments for networks arranged as cellular or square grids. Then, we present optimal channel assignments for cellular and square grids; these assignments exhibit a high value for δ₁ – the separation between channels assigned to adjacent stations. We prove an upper bound on δ₁ for such optimal channel assignments. This upper bound is greater than the value of δ₁ exhibited by our assignments. Based on empirical evidence, we conjecture that the value our assignments exhibit is a tight upper bound on δ₁.     

Nanoenergetic Composite of Mesoporous Iron Oxide and Aluminum Nanoparticles

Ordered mesoporous Fe₂O₃ was synthesized using cetyltrimethylammonium chloride (CTAC) and polyethylene glycol octadecyl ether (Brij 76) surfactant templates. The gel time was monitored as a function of the concentration ratio of precursor to the surfactant. As-prepared FeOOH gels were extracted in ethanol to remove the surfactant and calcined at 200–400°C for 6 h so that α-Fe₂O₃ is produced. The FTIR spectra of these gels reveal complete removal of surfactant and water impurities and the presence of Fe-O vibrations. TEM images show ordering of mesopores in the gels prepared using surfactant templating and no ordering of the pores in the gels prepared without surfactant. The gels after calcinations were mixed with aluminum nanoparticles to prepare nanoenergetic composites. The burn rate of the nanocomposites containing ordered mesoporous Fe₂O₃ mixed with Al nanoparticles was compared with the one containing Fe₂O₃ with no ordering of mesopores and Al nanoparticles.     

Formulation and comparative characterization of chitosan, gelatin, and chitosan-gelatin-coated liposomes of CPT-11-HCl

Liposomes containing phosphatidylcholine and cholesterol (uncoated) and coated by chitosan, gelatin, and combination of chitosan and gelatin were prepared by the modified ethanol injection method. The aim of this work was to formulate and characterize liposomes of camptothecin (CPT)-11-HCl (Irinotecan HCl) containing chitosan, gelatin, and both polymers as coating materials; and also to increase its circulation longevity when compared with the free drug while maintaining the agent in its active lactone form. Size, shape, zeta potential, encapsulation efficiency, stability study, in vitro, and in vivo release study were used for characterization of liposomes. The size of liposomes was in the order of uncoated < chitosan coated < gelatin coated < combination of chitosan and gelatin coated. The zeta potential of liposomes was in the order of combination of chitosan and gelatin coated > chitosan coated > gelatin coated > uncoated. The formulations showed the long-term stability. The encapsulation efficiency of liposomes was in order of combination of chitosan and gelatin coated > gelatin coated > chitosan coated > uncoated. The in vitro and in vivo release of drug was observed in the order of combination chitosan and gelatin coated > gelatin coated > chitosan coated > uncoated.