Mathematical models for drug diffusion through the compartments of blood and tissue medium

This paper is an attempt to establish the mathematical models to understand the distribution of drug administration in human body through oral and intravenous routes. Three models were formulated based on diffusion process using Fick’s principle and law of mass action. The rate constants governing the law of mass action were used on the basis of the drug efficacy at different interfaces. The Laplace transform and eigenvalue methods were used to obtain the solution of the ordinary differential equations concerning the rate of change of concentration in different compartments viz. blood and tissue medium. The drug concentration in the different compartments has been computed using numerical parameters. The graphs plotted illustrate the variation of drug concentration with respect to time using MATLAB software. It has been observed from the graphs that the drug concentration decreases in the first compartment and gradually increases in other compartments.Keywords: Drug diffusion; Laplace transform; Eigenvalue metho

Incomplete LU preconditioner for FMM implementation

An incomplete LU (ILU) preconditioner using the near-field matrix of the fast multipole method (FMM) is investigated to increase the efficiency of the iterative conjugate gradient squared (CGS) solver. Unlike the conventional LU, ILU requires no fill ins, and hence no extra memory and CPU time in computing the LU decomposed preconditioner. It is shown that, due to the nature of the near-field matrix, ILU preconditioning decreases the number of iterations dramatically. © 2000 John Wiley & Sons, Inc. Microwave Opt Technol Lett 26: 265–267, 2000.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/35044/1/18_ftp.pd

Mutation in NSUN2, which Encodes an RNA Methyltransferase, Causes Autosomal-Recessive Intellectual Disability

Causes of autosomal-recessive intellectual disability (ID) have, until very recently, been under researched because of the high degree of genetic heterogeneity. However, now that genome-wide approaches can be applied to single multiplex consanguineous families, the identification of genes harboring disease-causing mutations by autozygosity mapping is expanding rapidly. Here, we have mapped a disease locus in a consanguineous Pakistani family affected by ID and distal myopathy. We genotyped family members on genome-wide SNP microarrays and used the data to determine a single 2.5 Mb homozygosity-by-descent (HBD) locus in region 5p15.32–p15.31; we identified the missense change c.2035G>A (p.Gly679Arg) at a conserved residue within NSUN2. This gene encodes a methyltransferase that catalyzes formation of 5-methylcytosine at C34 of tRNA-leu(CAA) and plays a role in spindle assembly during mitosis as well as chromosome segregation. In mouse brains, we show that NSUN2 localizes to the nucleolus of Purkinje cells in the cerebellum. The effects of the mutation were confirmed by the transfection of wild-type and mutant constructs into cells and subsequent immunohistochemistry. We show that mutation to arginine at this residue causes NSUN2 to fail to localize within the nucleolus. The ID combined with a unique profile of comorbid features presented here makes this an important genetic discovery, and the involvement of NSUN2 highlights the role of RNA methyltransferase in human neurocognitive development

Velocity-space sensitivity of the time-of-flight neutron spectrometer at JET

The velocity-space sensitivities of fast-ion diagnostics are often described by so-called weight functions. Recently, we formulated weight functions showing the velocity-space sensitivity of the often dominant beam-target part of neutron energy spectra. These weight functions for neutron emission spectrometry (NES) are independent of the particular NES diagnostic. Here we apply these NES weight functions to the time-of-flight spectrometer TOFOR at JET. By taking the instrumental response function of TOFOR into account, we calculate time-of-flight NES weight functions that enable us to directly determine the velocity-space sensitivity of a given part of a measured time-of-flight spectrum from TOFOR

Relationship of edge localized mode burst times with divertor flux loop signal phase in JET

A phase relationship is identified between sequential edge localized modes (ELMs) occurrence times in a set of H-mode tokamak plasmas to the voltage measured in full flux azimuthal loops in the divertor region. We focus on plasmas in the Joint European Torus where a steady H-mode is sustained over several seconds, during which ELMs are observed in the Be II emission at the divertor. The ELMs analysed arise from intrinsic ELMing, in that there is no deliberate intent to control the ELMing process by external means. We use ELM timings derived from the Be II signal to perform direct time domain analysis of the full flux loop VLD2 and VLD3 signals, which provide a high cadence global measurement proportional to the voltage induced by changes in poloidal magnetic flux. Specifically, we examine how the time interval between pairs of successive ELMs is linked to the time-evolving phase of the full flux loop signals. Each ELM produces a clear early pulse in the full flux loop signals, whose peak time is used to condition our analysis. The arrival time of the following ELM, relative to this pulse, is found to fall into one of two categories: (i) prompt ELMs, which are directly paced by the initial response seen in the flux loop signals; and (ii) all other ELMs, which occur after the initial response of the full flux loop signals has decayed in amplitude. The times at which ELMs in category (ii) occur, relative to the first ELM of the pair, are clustered at times when the instantaneous phase of the full flux loop signal is close to its value at the time of the first ELM

The micro-economic impact and consequences of United Kingdom final participation schemes

Available from British Library Document Supply Centre-DSC:D204280 / BLDSC - British Library Document Supply CentreSIGLEGBUnited Kingdo

Some studies on Wirless Mesh Net Works (WMNS)

Wireless Mesh Networks is a new exciting technology that is anticipated to resolve the limitations and to significantly improve the performance of adhoc networks ,wireless local area networks(WLANS),wireless personal area networks(WPANS), and wireless metropolitan area networks(WMANs).Wireless Mesh Network is a decentralized networking technology that is currently being adapted to connect peer-to-peer clients and large-scale backbone networks. It will deliver wireless services for a large variety of applications in personal, local, campus, and metropolitan areas. Wireless Mesh Networks (WMNs) consist of mesh routers and mesh clients, where mesh routers have minimal mobility and form the backbone of WMNs. They provide network access for both mesh and conventional clients. Mesh routers have bridging and gateway functionality that in turn helps in the integration of WMNs with other existing networks such as internet, cellular, IEEE 802.15, IEEE 802.16, sensor networks , etc. However mesh clients can be either stationary or mobile and form a client mesh network among themselves and with mesh routers. In WMNs, nodes are comprised of mesh routers and mesh clients. Each node operates not only as a host but also as a router, forwarding packets on behalf of other nodes that may not be within direct wireless transmission range of their destinations. A WMN is dynamically self-organized and self-configured, with the nodes in the network automatically establishing and maintaining mesh connectivity among themselves (creating, in effect, an ad hoc network). This feature brings many advantages to WMNs such as low up-front cost, easy network maintenance, robustness, and reliable service coverage. Conventional nodes (e.g., desktops, laptops, PDAs, Pocket PCs, phones, etc.) equipped with wireless network interface cards (NICs) can connect directly to wireless mesh routers. Customers without wireless NICs can access WMNs by connecting to wireless mesh routers through, for example, Ethernet. Thus, WMNs will greatly help the users to be always-on-line anywhere anytime. Moreover, the gateway/bridge functionalities in mesh routers enable the integration of WMNs with various existing wireless networks such as cellular, wireless sensor, wireless-fidelity (Wi-Fi), worldwide inter-operability for microwave access (Wi MAX), Wi Media networks. Consequently, through an integrated WMN, the users of existing network can be provided with otherwise impossible services of these networks. WMN is a promising wireless technology for numerous applications, e.g., broadband home networking, community and neighbourhood networks, enterprise networking, building automation, etc. It is gaining significant attention as a possible way for cash strapped Internet service providers (ISPs), carriers, and others to roll out robust and reliable wireless broadband service access in a way that needs minimal up-front investments. With the capability of self-organization and self-configuration, WMNs can be deployed incrementally, one node at a time, as needed. Mesh networks provide a number of applications. For example in difficult environments such as emergency situations, tunnels, oil rigs, battlefield surveillance, high speed mobile video applications on board public transport or real time racing car telemetry. Some current applications are: 1. U.S. military forces are now using wireless mesh networking to connect their computers, mainly ruggedized laptops, in field operations. 2. Electric meters now being deployed on residences transfer their readings from one to another and eventually to the central office for billing without the need for human meter readers or the need to connect the meters with cables. 3. The laptops in the one laptop per child program use wireless mesh networking to enable students to exchange files and get on the Internet even though they lack wired or cell phone or other physical connections in their area. 4. Broadband home networking. 5. Community and neighbourhood networking. 6. Enterprise networking. 7. Metropolitan area networks. 8. Transportation systems 9. Building automation 10. Health and medical systems. 11. Security surveillance systems 12. P2P Communications However, to make a WMN be all it can be, considerable research efforts are still needed. For example, the available MAC and routing protocols applied to WMNs do not have enough scalability; the throughput drops significantly as the number of nodes or hops in a WMN increases. Similar problems exist in other networking protocols. Also a number of research challenges remain in all protocol layers. Consequently, all existing protocols from the application layer to transport, network MAC, and physical layers need to be enhanced or re-invented. Researchers have started to revisit the protocol design of existing wireless networks, especially of IEEE 802.11 networks, ad hoc networks, and wireless sensor networks, from the perspective of WMNs. Industrial standards groups are also actively working on new specifications for mesh networking. For example, IEEE 802.11, IEEE 802.15, and IEEE 802.16 all have established sub-working groups to focus on new standards for WMNs. New modulation schemes need to be developed in order to achieve higher transmission rate. For e.g., new wideband transmission schemes other than OFDM and UWB are needed. Advanced antenna processing including directional, smart and multiple antenna technologies is further investigated, since their complexity and cost are still too high for wide commercialization. Several other efforts are needed in fields like flexible spectrum management, cross layer design etc

Determination of optimal pumping configuration for an L-band EDFA with 980-nm LD and ASE pumps

L-band gain improvement through amplified spontaneous emission (ASE) pumping was conducted. For an L-band amplifier system employing ASE to improve gain, pumping the system counter-directionally with ASE and codirectionally with 980 mn would yield the best overall performance in terms of gain. Gain improvement as high as 6 dB was attained. (C) 2003 Wiley Periodicals, Inc