Quantification of midazolam,morphine and metabolites in plasma using 96‐well solid‐phase extraction and ultra‐performance liquid chromatography–tandem mass spectrometry

Currently, pharmacokinetic–pharmacodynamic studies of sedatives and analgesics are performed in neonates and children to find suitable dose regimens. As a result, sensitive assays using only small volumes of blood are necessary to determine drug and metabolite concentrations. We developed an ultra‐performance liquid chromatographic method with tandem mass spectrometry detection for quantification of midazolam, 1‐hydroxymidazolam, hydroxymidazolamglucuronide, morphine, morphine‐3‐glucuronide and morphine‐6‐glucuronide in 100 μL of plasma. Cleanup consisted of 96 wells micro‐solid phase extraction, before reversed‐phase chromatographic separation (ultra‐performance liquid chromatography) and selective detection using electrospray ionization tandem mass spectrometry. Separate solid‐phase extraction methods were necessary to quantify morphine, midazolam and their metabolites because of each group's physicochemical properties. Standard curves were linear over a large dynamic range with adequate limits of quantitation. Intra‐ and interrun accuracy and precision were within 85–115% (of nominal concentration using a fresh calibration curve) and 15% (coefficient of variation, CV) respectively. Recoveries were >80% for all analytes, with interbatch CVs (as a measure of matrix effects) of less than 15% over six batches of plasma. Stability in plasma and extracts was sufficient, allowing large autosampler loads. Runtime was 3.00 min per sample for each method. The combination of 96‐well micro‐SPE and UPLC‐MS/MS allows reliable quantification of morphine, midazolam and their major metabolites in 100 μL of plasma. Copyright © 2010 John Wiley & Sons, Ltd.     

Phase transitions of [M(H2O)6](MnO4)2 polycrystalline compounds,where M=Mg2+,Ni2+,Zn2+,Cd2+, studied by DSC

Phase transitions of [M(H₂O)₆](MnO₄)₂, where M=Mg, Ni, Zn and Cd, have been studied at 100–400 K by differential scanning calorimetry (DSC). One solid–solid phase transition for the compounds with M=Mg and Ni and two solid–solid phase transitions for these with M=Zn and Cd have been discovered. Additionally, three phase transitions, connected with three-stage melting process of these compounds, were also found. Thermodynamic parameters of the all detected phase transitions were calculated.     

Newly Detected Hydroxyls in Zeolite Mordenite by 1H MAS Spin Echo NMR Spectroscopy

The study of the acidic sites in zeolites is important to understand the nature of the acidic catalytic function.     

Cationic beta-cyclodextrin bilayer vesicles

Cationic amphiphilic beta-cyclodextrins, substituted with hydrophobic n-alkylthio chains at the primary hydroxyl side and hydrophilic omega-amino-oligo(ethylene glycol) units at the secondary side, form bilayer vesicles with a diameter of 30-35 nm (when alkyl = hexadecyl) or nanoparticles with a diameter of ca. 120 nm (when alkyl = hexyl) in water.     

Palladium catalysed copolymerisation of ethene with alkylacrylates: polar comonomer built into the linear polymer chain

Copolymerisation of ethene and alkylacrylates is catalysed by palladium modified with di(2-methoxyphenyl)phosphinobenzene-2-sulfonic acid (DOPPBS); a linear polymer is produced in which acrylate units are incorporated into the polyethylene backbone.     

Sucrose preculture to simplify cryopreservation of banana meristem cultures

A simple cryopreservation method is described for proliferating meristem cultures of banana (Musa spp.). It relies on a 2-week preculture on media containing 0.4 M sucrose followed by rapid cooling in liquid nitrogen. Different preculture media were screened for efficient protection of banana meristems against cryopreservation. Sucrose can be replaced by both fructose and glucose without significantly affecting post-thaw survival rates. A high BA concentration (0.1 mM) in the preculture medium results in less material available for cryopreservation, but does not affect cryoprotection. Culture in liquid media significantly improved post-thaw regeneration. The optimized cryopreservation protocol was applied on 36 banana accessions belonging to 8 different genomic groups. It is shown that post-thaw regeneration frequencies (ranging between 0 and 66 percent) are highly dependent on the genomic constitution of the banana cultivar.     

Virtual Private Ad Hoc Networking

The fact that a lot of applications require secure communication to take place only between a dynamic subset of distributed devices sharing a common context, is, from a network point of view, very challenging and demanding. Existing technologies such as VPN, P2P overlays or VLANs can only partially respond to these requirements. This observation is the key factor that has driven the proposal of the virtual private ad hoc network concept. Virtual private ad hoc networks (VPAN) are secure and self-organizing overlay networks on top of existing IP infrastructure that use ad hoc networking techniques to enable network connectivity. The underlying IP infrastructure can be the Internet, cellular networks, ad hoc networks, mesh networks … or combinations thereof. A virtual private ad hoc overlay network creates a transparent, shielded and trusted environment for the applications and services running on the participants' devices. The overlay uses internal addressing and ad hoc routing, thereby forming a virtual network on top of the physical infrastructure. In addition, the overlay must be self-organizing and self-maintaining upon member mobility or membership changes. This paper gives an overview of the potential applications, a high-level network architecture and the network challenges emerging from the novel concept of virtual private ad hoc networking. Jeroen Hoebeke was born in Ghent, Belgium in 1979. In 2002 he received the Masters degree in engineering (Computer Science) from the University of Ghent. In August 2002, he joined the Broadband Communications Networks Group. His PhD research includes the development of adaptive routing protocol techniques for mobile ad hoc networks. His main research interests are in ad hoc wireless communications and, more generally, in broadband wireless communications. Within the European MAGNET project, he is actively involved in the development of a network architecture and demonstrator for Personal Networks, with a prime focus on routing and connectivity. Gerry Holderbeke was born in Zottegem, Belgium in 1982. He graduated in Informatics at the University of Ghent in 2004. In August 2004 he joined the Broadband Communications Networks Group where he is currently working as a project developer. His research currently includes the development of an emulator for mobile ad hoc networks. His main research interests are in ad hoc networks and broadband wireless communications and involve routing, addressing and more generally, communication within mobile ad hoc networks and infrastructured networks. Within the European MAGNET project, he is actively involved in the development of a network architecture for Personal Networks, with a prime focus on the implementation of the routing architecture. Ingrid Moerman was born in Gent, Belgium in 1965. She received the degree in Electro-technical Engineering and the Ph.D degree from the Ghent University, Gent, Belgium in 1987 and 1992, respectively. Since 1987, she has been with the Interuniversity Micro-Electronics Centre (IMEC) at the Department of Information Technology (INTEC) of the Ghent University, where she conducted research in the field of optoelectronics. In 1997, she became a permanent member of the Research Staff at IMEC. Since 2000 she is part-time professor at the Ghent University. Since 2001 she has switched her research domain to broadband communication networks. She is currently involved in the research and education on broadband mobile & wireless communication networks and on multimedia over IP. The main research topics related to mobile & wireless communication networks are: wireless access to vehicles (high bandwidth & driving speed), adaptive QoS routing in wireless ad hoc networks, body area networks, protocol boosting on wireless links, design of fixed access/metro part, traffic engineering and QoS support in the wireless access network. Ingrid Moerman is author or co-author of more than 300 publications in the field of optoelectronics and communication networks. Bart Dhoedt received a degree in Engineering from the Ghent University in 1990. In September 1990, he joined the Department of Information Technology of the Faculty of Applied Sciences, University of Ghent. His research, addressing the use of micro-optics to realize parallel free space optical interconnects, resulted in a PhD degree in 1995. After a 2 year post-doc in opto-electronics, he became professor at the Faculty of Applied Sciences, Department of Information Technology. Since then, he is responsible for several courses on algorithms, programming and software development. His research interests are software engineering and mobile & wireless communications. Bart Dhoedt is author or co-author of approximately 70 papers published in international journals or in the proceedings of international conferences. His current research addresses software technologies for communication networks, peer-to-peer networks, mobile networks and active networks. Piet Demeester received the Masters degree in Electro-technical engineering and the Ph.D degree from the Ghent University, Gent, Belgium in 1984 and 1988, respectively. In 1992 he started a new research activity on broadband communication networks resulting in the IBCN-group (INTEC Broadband communications network research group). Since 1993 he became professor at the Ghent University where he is responsible for the research and education on communication networks. The research activities cover various communication networks (IP, ATM, SDH, WDM, access, active, mobile), including network planning, network and service management, telecom software, internetworking, network protocols for QoS support, etc. Piet Demeester is author of more than 300 publications in the area of network design, optimization and management. He is member of the editorial board of several international journals and has been member of several technical program committees (ECOC, OFC, DRCN, ICCCN, IZS, &).     

Identification of ethyl pyruvate and dihydrocinchonidine adducts by electrospray ionization mass spectrometry

Several ethyl pyruvate and dihydrocinchonidine adducts, formed by non-covalent interactions with alkali cations, have been identified for the first time using electrospray ionization mass and tandem mass spectrometry. This type of adduct may have an important role in asymmetric reactions of pyruvates in the presence of cinchonas.     

A Scalable Architecture for MPEG-4 Wavelet Quantization

Wavelet-based image compression has been adopted in MPEG-4 for visual texture coding. All wavelet quantization schemes in MPEG-4—Single Quantization (SQ), Multiple Quantization (MQ) and Bi-level Quantization—use Embedded Zero Tree (EZT) coding followed by an adaptive arithmetic coder for the compression and quantization of a wavelet image. This paper presents the OZONE chip, a dedicated hardware coprocessor for EZT and arithmetic coding. Realized in a 0.5 m CMOS technology and operating at 32 MHz, the EZT coder is capable of processing up to 25.6 Mega pixel-bitplanes per second. This is equivalent to the lossless compression of 31.6 8-bit grayscale CIF images (352 × 288) per second. The adaptive arithmetic coder processes up to 10 Mbit per second. The combination of the performance of the EZT coder and the arithmetic coder allows the OZONE to perform visual-lossless compression of more than 30 CIF images per second. Due to its novel and scalable architecture, parallel operation of multiple OZONEs is supported. The OZONE functionality is demonstrated on a PC-based compression system.