bluuebunny/crossref_metadata_2025 huggingface dataset:
Eclipsed distribution: A phenomenon of dual targeting of protein and its significance
Authors: Regev‐Rudzki Neta , Pines Ophry
Published: July 2007

One of the surprises from genome sequencing projects is the apparently small number of predicted genes in different eukaryotic cells, particularly human. One possible reason for this ‘shortage’ of genes is multiple distribution of proteins; a single protein is targeted to more than one subcellular compartment and consequently participates in different biochemical pathways and might have completely different functions. Indeed, in recent years, there have been reports on proteins that were found to be localized in cellular compartments other than those initially attributed to them. Furthermore, the phenomenon of highly uneven isoprotein distribution was recently observed and termed ‘eclipsed distribution’. In these cases, the amount of one of the isoproteins, in one of the locations, is significantly minute and its detection by standard biochemical and visualization methods is masked by the presence of the dominant isoprotein. In fact, the minute amounts of eclipsed proteins can be essential. Since detecting eclipsed distribution is difficult, we assume that this phenomenon is probably more common than currently recorded. Hence, developing methods for localization and functional detection of eclipsed proteins is a challenge in cell biology research. Finally, eclipsed distribution may lead to cellular pathologies as has been suggested to occur in human disorders such as Prion diseases and Alzheimer. This review provides a short description of the eclipsed distribution phenomenon followed by an overview of protein distribution mechanisms, examples of eclipsed distribution and experimental approaches for revealing these elusive proteins. BioEssays 29:772–782, 2007. © 2007 Wiley Periodicals, Inc..
Proteoglycans: key partners in bone cell biology
Authors: Lamoureux François , Baud'huin Marc , Duplomb Laurence , Heymann Dominique , Rédini Françoise
Published: July 2007

The diversity of bone proteoglycan (PG) structure and localisation (pericellular, extracellular in the organic bone matrix) reflects a broad spectrum of biological functions within a unique tissue. PGs play important roles in organizing the bone extracellular matrix, taking part in the structuring of the tissue itself as active regulators of collagen fibrillogenesis. PGs also display selective patterns of reactivity with several constituents including cytokines and growth factors, such as transforming growth factor‐β or osteoprotegerin thereby modulating their bio‐availability and biological activity in the bone tissue. In this review, the complex PG composition in bone will be addressed together with the specific role played by PGs (or their GAGs chains) in bone biology, as regulatory molecules for bone resorption and their involvement in bone tumor development. These roles have been determined after modulation of PG expression or mutations in their corresponding genes, which revealed specific roles for these compounds in bone pathologies (e.g. perlecan or glypican‐3 mutations observed respectively in chondrodysplasia or dysmorphic syndrome). Finally, the potential therapeutic interest of PGs is discussed based on recent data, more particularly on bone tumor‐associated osteolysis as these molecules are involved both in bone resorption and tumor development. BioEssays 29:758–771, 2007. © 2007 Wiley Periodicals, Inc.
Putting numbers on the network connections
Authors: Stormo Gary D. , Zhao Yue
Published: July 2007

DNA–protein interactions are fundamental to many biological processes, including the regulation of gene expression. Determining the binding affinities of transcription factors (TFs) to different DNA sequences allows the quantitative modeling of transcriptional regulatory networks and has been a significant technical challenge in molecular biology for many years. A recent paper by Maerkl and Quake1 demonstrated the use of microfluidic technology for the analysis of DNA–protein interactions. An array of short DNA sequences was spotted onto a glass slide, which was then covered with a microfluidic device allowing each spot to be within a chamber into which the flow of materials was controlled by valves. By trapping the DNA–protein complexes on the surface and measuring their concentrations microscopically, they could determine the binding affinity to a large number of DNA sequences that were varied systematically. They studied four TFs from the basic helix–loop–helix family of proteins, all of which bind to E‐box sites with the consensus CAnnTG (where “n” can be any base), and showed that variations in affinity for different sites allows each TF to regulate different genes. BioEssays 29:717–721, 2007. © 2007 Wiley Periodicals, Inc.
D‐Mannitol production by resting state whole cell biotransformation of D‐fructose by heterologous mannitol and formate dehydrogenase gene expression in Bacillus megaterium
Authors: Bäumchen Carsten , Roth Andreas H. F. J. , Biedendieck Rebekka , Malten Marco , Follmann Martin , Sahm Hermann , Bringer‐Meyer Stephanie , Jahn Dieter
Published: July 2007

An in vivo system was developed for the biotransformation of D‐fructose into D‐mannitol by the expression of the gene mdh encoding mannitol dehydrogenase (MDH) from Leuconostoc pseudomesenteroides ATCC12291 in Bacillus megaterium. The NADH reduction equivalents necessary for MDH activity were regenerated via the oxidation of formate to carbon dioxide by coexpression of the gene fdh encoding Mycobacterium vaccae N10 formate dehydrogenase (FDH). High‐level protein production of MDH in B. megaterium required the adaptation of the corresponding ribosome binding site. The fdh gene was adapted to B. megaterium codon usage via complete chemical gene synthesis. Recombinant B. megaterium produced up to 10.60 g/L D‐mannitol at the shaking flask scale. Whole cell biotransformation in a fed‐batch bioreactor increased D‐mannitol concentration to 22.00 g/L at a specific productivity of 0.32 g D‐mannitol (gram cell dry weight)–1 h–1 and a Dmannitol yield of 0.91 mol/mol. The nicotinamide adenine dinucleotide (NAD(H)) pool of the B. megaterium producing D‐mannitol remained stable during biotransformation. Intra‐ and extracellular pH adjusted itself to a value of 6.5 and remained constant during the process. Data integration revealed that substrate uptake was the limiting factor of the overall biotransformation. The information obtained identified B. megaterium as a useful production host for D‐mannitol using a resting cell biotransformation approach.
Glucosylation of phenols and phenylalkyl alcohols using cultured plant cells
Authors: Shimoda Kei , Sato Noriaki , Nakajima Nobuyoshi , Hamada Hatsuyuki , Ishihara Kohji , Hamada Hiroki
Published: July 2007

Cultured plant cells of Eucalyptus perriniana can convert phenol and phenylalkyl alcohols [C6H5(CH2)nOH, n=0–3] into the corresponding β‐D‐glucopyranosides in a good yield. The cells preferentially glucosylated phenylmethanol (n=1, 59% yield) rather than phenol (n=0, 49%), 2‐phenylethanol (n=2, 38%), and 3‐phenylpropan‐1‐ol (n=3, 20%). On the other hand, 2‐, 3‐, and 4‐hydroxyphenylmethanols were also glucosylated to (hydroxymethyl)phenyl β‐D‐glucopyranosides and (hydroxyphenyl)methyl β‐D‐glucopyranosides by cultured E. perriniana cells.
Megan's law and its impact on community re‐entry for sex offenders
Authors: Levenson Jill S. , D'Amora David A. , Hern Andrea L.
Published: July 2007

Community notification, known as “Megan's Law,” provides the public with information about known sex offenders in an effort to assist parents and potential victims to protect themselves from dangerous predators. The purpose of this study was to explore the impact of community notification on the lives of registered sex offenders. Two hundred and thirty‐nine sex offenders in Connecticut and Indiana were surveyed. The negative consequences that occurred with the greatest frequency included job loss, threats and harassment, property damage, and suffering of household members. A minority of sex offenders reported housing disruption or physical violence following community notification. The majority experienced psychosocial distress such as depression, shame, and hopelessness. Recommendations are made for community notification policies that rely on empirically derived risk assessment classification systems in order to better inform the public about sex offenders' danger while minimizing the obstacles that interfere with successful community reintegration. Copyright © 2007 John Wiley & Sons, Ltd.
Power in community psychology research and practice
Authors: Fisher Adrian T. , Sonn Christopher C.
Published: July 2007

While power underpins so much of community psychology, it is not usually the focus of research or practice. Even empowerment approaches lack clear definition of the power against which they are operating. This article introduces a model developed at Peabody College, Vanderbilt University, to understand various power dimensions and levels at which it can have impacts. Such a multifaceted model has facilitated the series of articles that follow – re‐analysing the authors' work with power as the core element in the analyses, and understanding the different levels of analysis, sources of power, and ways in which power imbalances can be redressed. Copyright © 2007 John Wiley & Sons, Ltd.
Interrogating power: the case of arts and mental health in community projects
Authors: Lawthom Rebecca , Sixsmith Judith , Kagan Carolyn
Published: July 2007

In this paper, we use the multi‐dimensional model of power to interrogate arts and mental health community based projects. Using data retrospectively gathered during a series of participative evaluations, we re‐analyse the data focusing on the ways in which power is located and negotiated across levels of analysis and multiple ecological domains. Evidence from the evaluations is richly presented illustrating power at the micro, meso and macro level. Whilst the model offers a rich reading of power, it is difficult to operationalize historically. Moreover, the static nature of the model fails to adequately capture the multiplicity of sometimes polar positions adopted. Engaging in a particular framework of community psychology, we argue that this project may be seen as part of a wider prefigurative action research agenda. Copyright © 2007 John Wiley & Sons, Ltd.
Child poverty and government policy: the contesting of symbolic power in newspaper constructions of families in need
Authors: Barnett Alison , Hodgetts Darrin , Nikora Linda , Chamberlain Kerry , Karapu Rolinda
Published: July 2007

News media play a central role in processes of symbolic power through which social issues are defined and solutions legitimized. This paper explores the role of newspaper coverage in the public construction of the New Zealand Government'sWorking for Familiespackage designed to address child poverty. This package was criticized publicly by the Child Poverty Action Group (CPAG) for targeting financial support to working families and neglecting families who derive their income from state benefits. We document the resulting news controversy through analyses of press releases from Government and CPAG, the accounts of journalists and representatives of CPAG, news reports and four focus group discussions with beneficiary parents. We propose that psychologists engage more fully with processes of symbolic power currently shaping public constructions of poverty and policy responses. Copyright © 2007 John Wiley & Sons, Ltd.
Macroscopic thrombus formation on angioplasty equipment following antithrombin therapy with enoxaparin
Authors: Dana A. , Nguyen C.M. , Cloutier S. , Barbeau G.R.
Published: July 2007

Increasing evidence suggests that treatment with the low molecular weight heparin enoxaparin during percutaneous coronary intervention (PCI) is safe and effective. We evaluated the incidence and consequences of periprocedural macroscopic thrombus formation on PCI equipment following antithrombin therapy with enoxaparin. Between April 2003 and December 2004, all patients undergoing cardiac catheterization following antithrombin therapy with enoxaparin were evaluated. All patients had blood sampled at the onset of procedure for subsequent measurement of anti‐factor‐Xa levels. Of the 4,504 patients who underwent PCI during this period, in 122 (3%) the procedure was performed within 8 hr of treatment with subcutaneous enoxaparin and no additional unfractionated heparin (UFH) was used periprocedurally. Of these, macroscopic thrombus was observed on PCI equipment in 6 patients (5%) necessitating withdrawal of all catheters and wires. All patients had therapeutic anti‐factor‐Xa levels at the time of PCI, and had been treated with double antiplatelet therapy with aspirin and clopidogrel. No periprocedural thrombus was observed in 356 patients who were ≫12 hr of the last dose of enoxaparin and received UFH at the time of PCI. Following observation of thrombus, additional anticoagulation with UFH resulted in significant epistaxis in one patient. In another patient, the procedure was complicated by distal coronary embolization. Percutaneous coronary intervention following antithrombin therapy with enoxaparin is associated with a 5% incidence of macroscopic thrombus formation on PCI equipment. The necessity for subsequent exchange of all equipment and/or the need for additional anticoagulation may have disastrous consequences for the patient. Our findings suggest that the safety of antithrombin therapy with low molecular weight heparin during PCI requires further evaluation. © 2007 Wiley‐Liss, Inc.
Percutaneous closure of an iatrogenic ventricular septal defect following mechanical aortic valve replacement using the transseptal technique
Authors: Klein Andrew J. , Garcia Joel A. , Carroll John D.
Published: July 2007

Iatrogenic ventricular septal defects (VSDs) following aortic valve replacement are relatively uncommon and are challenging to close percutaneously given their typical proximity to the prosthetic valve. We describe the successful percutaneous closure of an iatrogenic VSD in a patient with a recent mechanical AVR using the transseptal approach. © 2007 Wiley‐Liss, Inc.
The sphere in a uniform RF field—Revisited
Authors: Bidinosti C.P. , Chapple E.M. , Hayden M.E.
Published: July 2007

We consider eddy current generation in weakly conducting spheres as a means to characterize RF power dissipation over the frequency range 0.1–1.2 MHz, which is relevant to MRI in very low magnetic fields. We provide a complete, yet simple, theoretical analysis of the homogeneous sphere in a uniform RF field and summarize expressions for the current density, power dissipation, and magnetic field for the limiting case of the nonmagnetic conducting sphere. Experiments are performed on spherical saline phantoms using a whole‐body B1‐coil as the RF field source. Changes in the quality factor and magnetic field profile of the coil are measured and used to extract a value for conductivity of the saline solution. This conductivity is known independently from the NaCl concentration in the phantom. Excellent agreement between the two values confirms the theoretical analysis. © 2007 Wiley Periodicals, Inc. Concepts Magn Reson Part B (Magn Reson Engineering) 31B: 191–202, 2007
Comparison of three algorithms for solving linearized systems of parallel excitation RF waveform design equations: Experiments on an eight‐channel system at 3 Tesla
Authors: Zelinski Adam C. , Wald Lawrence L. , Setsompop Kawin , Alagappan Vijayanand , Gagoski Borjan A. , Goyal Vivek K , Hebrank Franz , Fontius Ulrich , Schmitt Franz , Adalsteinsson Elfar
Published: July 2007

Three algorithms for solving linearized systems of RF waveform design equations for calculating accelerated spatially‐tailored excitations on parallel excitation MRI systems are presented. Their artifact levels, computational speed, and RF peak and root‐mean‐square (RMS) voltages are analyzed. An SVD‐based inversion method is compared with conjugate gradient least squares (CGLS) and least squares QR (LSQR), two iterative algorithms designed to solve large linear systems. The excitation pulses calculated using these methods are used in both Bloch simulations and imaging experiments on an actual eight‐channel parallel excitation coil array implemented on a 3T human scanner. Specifically, RF waveforms are designed for accelerated 2D spiral k‐space trajectories to produce a variety of 2D target excitations and for a 3D spokes trajectory to produce a uniform thin‐slice excitation. Overall, these experiments show that waveforms designed using LSQR and CGLS have significantly lower peak and RMS waveform voltages and produce excitations with fewer artifacts than those generated by the SVD‐based method. © 2007 Wiley Periodicals, Inc. Concepts Magn Reson Part B (Magn Reson Engineering) 31B: 176–190, 2007
SAR simulation and the effect of mode coupling in a birdcage resonator
Authors: Reza S. , Vijayakumar S. , Limkeman M. , Huang F. , Saylor C.
Published: July 2007

The issues related to the simulation of specific absorption rate (SAR) in a high frequency magnetic resonance coil are discussed in this work. Using simulation results, it is shown that the effect of the nonimaging modes on SAR can be substantial and thus must be taken into account. Also a technique for the estimation of SAR for coils with complicated geometry is presented. The presented technique will be useful in cases where the conventional finite difference time domain simulation is not practical because of large memory requirement and/or excessively long computation time. © 2007 Wiley Periodicals, Inc. Concepts Magn Reson Part B (Magn Reson Engineering) 31B: 133–139, 2007
Task‐performing dynamics in irregular, biomimetic networks
Authors: Messinger Susanna M. , Mott Keith A. , Peak David
Published: July 2007

Understanding self‐organized collective dynamics—especially in sparsely connected, noisy, and imperfect networks—has important implications for designing and optimizing task‐performing technological systems as well as for deciphering biological structures and functions. We note that stomatal arrays on plant leaves might provide an ideal example of task‐performance in this context. Guided by observations of stomatal networks, we examined a simple model of task‐performing, collective dynamics that included state noise, spatial rule heterogeneity, dynamic modules, and network rewiring. Our results indicate that task‐performance in such networks can actually be enhanced by various kinds of spatial and temporal irregularity. © 2007 Wiley Periodicals, Inc. Complexity 12: 14–21, 2007
What is the complexity of a distributed computing system?
Authors: Ranganathan Anand , Campbell Roy H.
Published: July 2007

Distributed computing systems are becoming bigger and more complex. Although the complexity of large‐scale distributed systems has been acknowledged to be an important challenge, there has not been much work in defining or measuring system complexity. Thus, today, it is difficult to compare the complexities of different systems, or to state that one system is easier to program, to manage, or to use than another. In this article, we try to understand the factors that cause computing systems to appear very complex to people. We define different aspects of system complexity and propose metrics for measuring these aspects. We also show how these aspects affect different kinds of people—viz. developers, administrators, and end‐users. On the basis of the aspects and metrics of complexity that we identify, we propose general guidelines that can help reduce the complexity of systems. © 2007 Wiley Periodicals, Inc. Complexity 12: 37–45, 2007
New structures of four‐phase oscillators obtained by strongly interweaving mono‐phase limit‐cycle oscillators
Authors: Yardeny D. , Kaplan B. Z. , Horen Y.
Published: July 2007

The present work is a part of our effort of developing multiphase oscillators. The particular system dealt with here is that of strongly nonlinearly coupled four oscillators that form a multiphase source. Such sources possess potential applications in power electronics, in phased‐array antennas, and in modern methods of modulation and especially in demodulating multi‐phased modulated signals. The present system can be interpreted as embracing four two‐phase oscillators. Nevertheless, as a result of the strong coupling, the second state equation of each oscillator merges with the first equation of the following oscillator. The resulted four‐phase source is, therefore, represented by merely four state equations. The applications related to communications (especially those related to receivers) may be susceptible to the noise performance of the source. We believe that the presently suggested system, which relies on strong coupling of oscillators, is advantageous in its noise performance in comparison to more straightforward recently described multiphase sources, which incorporate loosely coupled oscillators. Copyright © 2007 John Wiley & Sons, Ltd.
LIVE‐NET — An interactive switched video network for the university of London
Authors: Powter E. J. , Beckwith R. C.
Published: July 2007

British Telecom has installed, for the University of London, a switched video network, LIVE‐NET. The network links together seven University locations, and offers four both‐way full bandwidth video channels between each site and a central location. A data path is also provided. A video switch at the centre enables the network to be configured in many different ways. This paper discusses how the technology used for LIVE‐NET came out of that used for BT's Switched Star Cable TV system, and considers how the services that it provides are being used by the University. The network offers more flexibility than conventional video conferencing networks, and this has an influence on human factors and terminal equipment. This type of network bridges the gap between relatively cheap one way cable TV systems and the much more expensive two‐way specialized vision circuits.
Microwave‐multiplexed lightwave systems: A new approach to wideband networks
Authors: Olshansky Robert
Published: July 2007

For the last fifteen years the attention of the fibre‐optic community has been principally focused on developing baseband digital transmission system for transmitting time‐division‐multiplexed voice channels over long distance and interoffice routes. Attention has now shifted to extending the fibreoptic network to the subscriber loop and to providing a multitude of new services through lightwave networks.

Based on the results reviewed here, it is apparent that microwave‐multiplexing techniques provide a new and attractive way to transmit wideband services over optical fibre. By allowing lightwave systems designers to use and combine the complete range of available electronics, including both analog and digital electronics, and both baseband and microwave techniques, a great number of new possibilities arise for exploiting the bandwidth of lightwave components and for designing wideband lightwave networks. Over the next few years the microwave‐multiplexing techniques described in this article may fundamentally change the way we use lightwave technology.
Paris: An approach to integrated high‐speed private networks
Authors: Cidon Israel , Gopal Inder S.
Published: July 2007

This paper describes a design of a high‐speed packet switching system for integrated voice, video and data communications. The system makes use of a simplified network architecture in order to achieve the low packet delay and high nodal throughput necessary for the transport of voice and video. A prototype of this system has been implemented and is now being tested under a variety of packet traffic loads. We have demonstrated that this system provides a cost‐effective solution for private integrated networks.
Video transmission formats — A tutorial review
Authors: Crawford David I.
Published: July 2007

With the demand for new television services in cabled systems increasing, there is an abundance of proposals for new transmission formats. This paper provides a tutorial review of existing analogue television transmission formats for distribution to the home; its scope does not cover studio or digital signal formats. The paper shows from first principles how the more efficient component signals used in modern video transmission formats are derived from three independent primary colour signals at source. Both composite and component signal formats are then described, and a comprehensive range of specific examples are compared.
A high‐speed four‐channel subscriber fibre‐optic link for broadband networks
Authors: Stephens W. E. , Rosin E. A.
Published: July 2007

This paper describes the performance of a 560 Mb/s digital fibre‐optic link designed specifically for possible use in a broadband integrated services digital network (BISDN) environment. Four 140 Mb/s non‐return‐to‐zero (NRZ) channels are time division multiplexed using a bit‐by‐bit multiplexing strategy and transmitted using potentially low cost 1.3 μm EE‐LED and laser sources. A 10−9 bit error rate with a power level of ‐34 dBm was achieved for each independent channel over a distance of 10 km.
Wavelength‐division integration of services in fibre‐optic networks
Authors: Perrier Philippe A. , Prucnal Paul R.
Published: July 2007

A flexible fibre‐optic network architecture for the integration of multiple services is proposed and demonstrated. The traffic requirements of each service are addressed by using distinct wavelengths and multiple‐access schemes. The separation of services by wavelength eliminates the need for complex bandwidth allocation and multiplexing techniques. As a consequence of wavelength‐division, the network can be seen as consisting of a collection of subnetworks, each carrying a different service. Different data rates and signal formats are easily accommodated. To the user, however, the integration appears complete.
Metropolitan area networks and ATM technology
Authors: Mollenauer James F.
Published: July 2007

Metropolitan area networks are evolving to fill the gap between local and wide area networks. The standards organization for such networks, IEEE Project 802.6, is defining a standard with unique advantages in scheduling and failure recovery. It is highly compatible with broadband ISDN and ATM switch technology. The resulting combination will be a seamless network embracing both customer buildings within metropolitan areas and world‐wide interconnection.
Circuit emulations
Authors: Kim C. K. , Lee S. H. , Wu L. T.
Published: July 2007

The deployment of broadband public packet networks requires integrating packet technology into the larger, predominantly circuit‐switched world. In this paper, we translate the need for circuit‐switched network compatibility into a class of packet transport capabilities referred to as circuit emulations. We first present our initial estimates of performance goals for emulating circuit‐switched connections in a broadband packet network. To show the feasibility of this new networking approach, we then describe a switch design capable of satisfying the stringent packet loss rate and delay requirements for emulating circuits at the DS1 rate and above. Finally, we demonstrate the ability to reconstruct continuous signals from emulated circuits using a simple time‐averaging clock recovery scheme based on a computer simulation model.
The virtual path identifier and its applications for routeing and priority of connectionless and connection‐orientated services
Authors: Adams J. L.
Published: July 2007

A feature of ATM networks is that they can be configured with paths routed through a number of switching stages which can each take many thousands of connections and which can each be assigned capacity dynamically. A large number of such paths, known as virtual paths, can be established from each network node without consuming much network capacity, since they can be assigned limited or zero capacity when unused. Virtual paths can be used to provide faster connection set‐up times or a faster transfer time for connectionless messages, and greater routeing flexibility. In particular they can be used to provide very fast transfer of signalling information between any two processors in a set of many thousands configured as a distributed processing control plane. They can also be used to indicate quality of service (QOS) values. These different issues are discussed in this paper, leading to some recommendations on the size of the virtual path identifier (VPI) field suitable for signalling and connectionless and connection‐orientated services.
Realization of a 450 mhz cable tv system compatible with existing networks
Authors: Lange Heinz
Published: July 2007

This paper describes the realization in West Germany of a 450 MHz cable TV system, which matches into the infrastructure already formed by the existing 300 MHz systems. The studies and developments done to achieve this are described, and the results of a field trial detailed. Finally the impact of the new MAC standard is discussed.
Advances in the British telecom switched‐star cable TV system to MKII and beyond
Authors: Boswell E. J. , Fox J. R. , Ritchie W. K.
Published: July 2007

The paper reviews the first switched‐star network (SSN) deployed in Westminster. It then goes on to look at the MkII development, based on a new switching chip, which allows the use of significantly smaller street cabinets. Finally work on a broadband, integrated service, all‐fibre network, is introduced as the current step in the SSN development programme.
The customer premises network for ATM: Architecture and standardization issues
Authors: Pauwels B.
Published: July 2007

This paper discusses the architecture of ATM‐based customer premises networks (CPN), which can easily be tailored to the needs of a broad range of residential and (small) business customers.

A first part analyses the functions of the classical CCITT reference model, and regroups them into building blocks for a new model. This model features a high degree of modularity, and interfaces with low‐level functionality. The building blocks for this CPN are the network termination, connection subnets and switching subnets.

Following this, some issues related to the user‐network interface standardization are addressed, as this interface has potential to be a candidate for application in the whole CPN. Owing to publication schedules, the author did not have the opportunity to take into account the recent decisions taken by CCITT concerning ATM standards.
Management of capacity and control in broadband ISDN
Authors: Burgin John L.
Published: July 2007

The trend towards integration of services onto a single network and the addition of accompanying control features has led to an increase in the complexity of functional signalling protocols. A continuing dramatic reduction in the cost of traffic‐carrying capacity has meant that call control costs are becoming an increasingly significant component of the total network cost. In BISDN, the support of many diverse services may result in an excessive control cost. To avoid this potential problem, virtual paths may be used. Capacity may be reserved on virtual paths to simplify the set‐up procedure for individual calls. One benefit of this approach is that the cost of establishing a virtual path is shared among all individual connections which subsequently use it. However, this reduced control cost comes at the expense of installing additional traffic carrying capacity. This paper describes techniques for the management of traffic carrying capacity and control mechanisms in BISDN and presents a cost‐benefit analysis to determine policies for reserving capacity on virtual paths. Significant savings in the total BISDN cost can result from the use of virtual paths.
The effect of eliminating the standby state on DQDB performance under overload
Authors: Zukerman Moshe , Potter Philip G.
Published: July 2007

This paper provides first a description of DQDB focusing mainly on its distributed queue operation. Then, the performance of DQDB under traffic saturation for the cases of concentrated and widely separated sources is studied and discussed with a special focus on the effect of the elimination of the STANDBY state on fairness and throughput. Finally, the performance with variable bit rate video traffic is examined by simulation for a small DQDB network whereby a comparison of performance results between DQDB with and without STANDBY is presented.
Comparison of ATM switching architectures
Authors: Wulleman Raymond , van Landegem Thierry
Published: July 2007

Clear examination of work currently done within CCITT indicates the importance of a broadband telecommunication network. As this network should be capable of integrating all services in an efficient way—in order to reduce cost—the asynchronous transfer mode (ATM) was selected by CCITT as the target transfer mode for implementing the broadband integrated services digital network (BISDN). This selection implies that the switching nodes in the BISDN network are capable of supporting this high‐speed packet and connection‐orientated technique. Within the literature different switching node architectures based upon ATM have been proposed. All of these architectures should meet the high‐speed and high‐throughput requirements so as to cope with the delay and jitter performance objectives. In a first step this paper describes alternative switching techniques for the basic building block (switching element) of a switching node. A common model architecture of the switching element is drafted. A classification of switching elements described in the literature is derived and the influence on the complexity and performance is weighted. In a second step the switching node architecture is further elaborated according to the control and flexibility requirements. Core (switching) and edge (switching related) functions are listed, and possible functional partitionings are discussed. Finally, these ATM switching architectures are compared according to a background frame consisting of several straightforward comparison points such as the buffering strategy, the internal routeing method, the switching overhead, the connection‐orientated or connectionless operation, etc.
Traffic studies of a multiplexer in an ATM network and applications to the future broadband ISDN
Authors: Lampe D.
Published: July 2007

In the first part of this paper the influence of the arrival process on these three performance parameters is discussed. The values of these three performance parameters depend strongly on the utilization distribution over the input trunks of the multiplexer while the total utilization on the input trunks is fixed. If there is the same utilization on all input trunks, the values of these three performance paramters reach a maximum. This result is also valid for an ATM switching matrix with a separate FIFO buffer at each output trunk.

In the second part of this paper some examples are provided of how to apply the results of these studies to the future broadband ISDN which is intended to transmit services with very high bit rates (e.g. 135 Mb/s) as well as services with very low bit rates (e.g. 64 kb/s).
Buffer sizing for synchronous self‐routeing broadband packet switches with bursty traffic
Authors: Hou Ting‐Chao , Lucantoni David M.
Published: July 2007

Previous studies on the performance of synchronous self‐routeing packet switches have assumed that the input traffic is random, i.e. there is no correlation between adjacent packet arrivals. This assumption is generally not valid in the data communication environment (e.g. host‐to‐host communication) where a file transfer usually generates a string of correlated packets. The consequence is that the random traffic assumption greatly underestimates the buffer requirement of the switch. In this paper, we model each input traffic stream as a binary source as a first step to understand the performance of a packet switch in a bursty traffic environment. We found that, given a fixed traffic load (or switch utilization), the required buffer size increases linearly as the burstiness index (the average burst length) of the traffic increases. In addition, the required buffer size is more sensitive to the burstiness of the traffic, when the average traffic load is higher and when the packet loss requirement is more stringent.

Initial applications of broadband packet switches are likely to be the interconnections of LANs and hosts. The results of the study indicate that the high burstiness in certain broadband traffic significantly reduces the allowable switch utilization, given a fixed amount of buffers. To increase the switch utilization, an appropriate congestion control mechanism needs to be implemented.
A high‐performance switch fabric for integrated circuit and packet switching
Authors: Ahmadi Hamid , Denzel Wolfgang E. , Murphy Charles A. , Port Erich
Published: July 2007

This paper describes an architecture for a high‐performance switching fabric that can accommodate circuit‐switched and packet‐switched traffic in a unified manner. The switch fabric is self‐routeing and uses fixed‐length minipackets within the switching fabric for all types of connections. Its kernel architecture is based on a routeing topology with individual connection paths from all inputs to all outputs and with FIFO queuing at each output. Owing to the disjoint connection paths, there is no internal blocking, and because of output queueing, output port blocking is prevented to a great extent. The uniformity in architecture allows construction of any size fabric from a single basic module which could be realized on a single chip. Larger‐size configurations can be realized either as single‐stage or multistage configuration. The second part of this paper discusses performance aspects and gives results and dimensioning guidelines for both circuit‐switched and packet‐switched traffic.
Intrusion detection and tolerance: A global scheme
Authors: Djemaiel Yacine , Rekhis Slim , Boudriga Noureddine
Published: July 2007

Protecting implemented security mechanisms and trusting their output (e.g. log files) when the host, under which they are deployed, is compromised, is among the major challenges that have to be faced. To fulfil this need, recent advances in security have considered the design of storage‐based intrusion detection system, which detect intrusions by looking at the low‐level disk requests patterns. However, these systems neither tolerate intrusions, nor do they distinguish whether the disk requests are generated by legitimate or malicious processes; and consequently, they generate a lot of false negative and positive alerts. In this paper, we present a Cooperative Intrusion Detection and Tolerance System, called CIDTS, which takes advantage of the information that are available at the network, host operating system, and storage level to better detect intrusion attempts in their early stages, even when the host is compromised. To allow cooperation, the disk communication interface that transports requests between the storage level and the host level is extended to forward information about the processes that generate the request. The paper also provides intrusion tolerance capabilities and provides techniques to support investigation activities. Copyright © 2007 John Wiley & Sons, Ltd.
Highest‐density forecast regions for nonlinear and non‐normal time series models
Authors: Hyndman Rob J.
Published: July 2007

Forecast regions are a common way to summarize forecast accuracy. They usually consist of an interval symmetric about the forecast mean. However, symmetric intervals may not be appropriate forecast regions when the forecast density is not symmetric and unimodal. With many modern time series models, such as those which are non‐linear or have non‐normal errors, the forecast densities are often asymmetric or multimodal. The problem of obtaining forecast regions in such cases is considered and it is proposed that highest‐density forecast regions be used. A graphical method for presenting the results is discussed.
Level shifts, temporary changes and forecasting
Authors: Trívez F. Javier
Published: July 2007

The purpose of this paper is to analyze the effect of not treating Level Shift and Temporary Change outliers on the point forecasts and prediction intervals from ARIMA models. One of the principal conclusions is that the outliers of the type discussed here considerably increase the inaccuracy of point forecasts, although the latter depends not only on the time of occurrence of the outliers from the forecast origin but also on the type of ARIMA processes under consideration. However, regardless of the time of occurrence and of the type of ARIMA processes considered, Level Shifts and Temporary Changes significantly affect the width of the prediction intervals.
Dynamik für die Forschung
Authors: Kleiner Matthias
Published: July 2007

Die Europäisierung von Förderprogrammen setzt verbindliche Standards und transparente Verfahren voraus
Wenn Europa verstaubt …
Authors: Heintzenberg Jost
Published: July 2007

Von Marokko nach Europa – Den Weg und die Wettereffekte einer fünf Kilometer hohen Wüstenstaubwolke studieren Wissenschaftler in einem Großexperiment
Wilms' tumor with an apparently balanced translocation t(X;18) resulting in deletion of the WTX gene
Authors: Han Moonjoo , Rivera Miguel N. , Batten Julie M. , Haber Daniel A. , Cin Paola Dal , Iafrate A. John
Published: July 2007

The recent description of a new X chromosome tumor suppressor gene, WTX, that is commonly inactivated in Wilms' tumor prompted us to examine the possible involvement of WTX in a case of Wilms' tumor containing an apparently balanced reciprocal translocation between chromosomes X and 18 (t(X;18)(q11;p11)). Fluorescence in situ hybridization (FISH) analysis of paraffin tumor sections indeed revealed a deletion of the WTX locus at Xq11. High‐resolution array comparative genomic hybridization (array CGH) analysis of tumor DNA revealed a 1.5 Mb chromosome deletion encompassing the WTX gene at Xq11. No loss of genetic material was detected on chromosome 18. Interestingly, unlike most tumors with acquired chromosomal translocations, where a new fusion oncogene or promoter‐oncogene fusion is created and drives tumor growth, the t(X;18) in this tumor appears to drive tumorigenesis via deletion of a tumor suppressor. This case demonstrates the importance of array CGH and FISH as adjuncts in tumor cytogenetics and in identifying pathogenic microdeletions in “balanced” translocations that are not truly balanced. © 2007 Wiley‐Liss, Inc.
CC‐chemokine ligand 17 gene therapy induces tumor regression through augmentation of tumor‐infiltrating immune cells in a murine model of preexisting CT26 colon carcinoma
Authors: Kanagawa Naoko , Niwa Masakazu , Hatanaka Yutaka , Tani Yoichi , Nakagawa Shinsaku , Fujita Takuya , Yamamoto Akira , Okada Naoki
Published: July 2007

Chemokines, which regulate leukocyte trafficking and infiltration of local sites, are attractive candidates for improving the efficacy of cancer immunotherapy by enhancing the accumulation of immune cells in tumor tissue. Herein, we evaluated the antitumor effects of intratumoral injection of RGD fiber‐mutant adenoviral vectors (AdRGDs) encoding the chemokines CCL17, CCL19, CCL20, CCL21, CCL22, CCL27, XCL1 or CX3CL1 in a murine model of preexisting CT26 colon carcinoma. Among these 8 chemokine‐expressing AdRGDs, injection of AdRGD‐CCL17 most effectively induced tumor regression and generated specific immunity in rechallenge experiments. Tumor elimination activity by intratumoral injection of AdRGD‐CCL17 depended on both the vector dose and the number of injections, and mainly required CD8+ CTLs in an effector phase as confirmed by analysis using BALB/c nude mice and an in vivo depletion assay. In addition, CCL17 gene transduction induced significant increases in the number of infiltrating macrophages and CD8+ T cells in CT26 tumors, and changed the tumor microenvironment to an immunologic activation state in which there was enhanced expression of lymphocyte activation markers and cell adhesion molecules. Thus, our data provide evidence that CCL17 gene transduction of local tumor sites is a promising approach for the development of a cancer immunogene therapy that can recruit activated tumor‐infiltrating immune effector cells. © 2007 Wiley‐Liss, Inc.
Overexpression of the paternally expressed gene 10 (PEG10) from the imprinted locus on chromosome 7q21 in high‐risk B‐cell chronic lymphocytic leukemia
Authors: Kainz Birgit , Shehata Medhat , Bilban Martin , Kienle Dirk , Heintel Daniel , Krömer‐Holzinger Elisabeth , Le Trang , Kröber Alexander , Heller Gerwin , Schwarzinger Ilse , Demirtas Dita , Chott Andreas , Döhner Hartmut , Zöchbauer‐Müller Sabine , Fonatsch Christa , Zielinski Christoph , Stilgenbauer Stephan , Gaiger Alexander , Wagner Oswald , Jäger Ulrich
Published: July 2007

We report high expression of the maternally imprinted gene PEG10 in high‐risk B‐CLL defined by high LPL mRNA expression. Differential expression was initially identified by microarray analysis and confirmed by real time PCR in 42 B‐CLL patients. mRNA expression ranged from 0.3‐ to 375.4‐fold compared to normal peripheral blood mononuclear cells (PBMNC). Expression levels in CD19+ B‐CLL cells were 100‐fold higher than in B‐cells from healthy donors. PEG10 expression levels in B‐CLL patient samples remained stable over time even after chemotherapy. High PEG10 expression correlated with high LPL expression (p = 0.001) and a positive Coombs' test (p = 0.04). Interestingly, similar expression patterns were observed for the neighbouring imprinted gene sarcoglycan‐ε (SGCE). Monoallelic expression and maintained imprinting of PEG10 were found by allele‐ or methylation‐specific PCR. The intensity of intracellular staining of PEG10 protein corresponded to mRNA levels as confirmed by immunofluorescence staining. Short term knock‐down of PEG10 in B‐CLL cells and HepG2 cells was not associated with changes in cell survival but resulted in a significant change in the expression of 80 genes. However, long term inhibition of PEG10 led to induction of apoptosis in B‐CLL cells. Our data indicate (i) a prognostic value of PEG10 in B‐CLL patients; (ii) specific deregulation of the imprinted locus at 7q21 in high‐risk B‐CLL; (iii) a potential functional and biological role of PEG10 protein expression. Altogether, PEG10 represents a novel marker in B‐CLL. © 2007 Wiley‐Liss, Inc.
Quantitative hypermethylation of NMDAR2B in human gastric cancer
Authors: Liu Jun‐Wei , Kim Myoung Sook , Nagpal Jatin , Yamashita Keishi , Poeta Luana , Chang Xiaofei , Lee Juna , Park Hannah Lui , Jeronimo Carmen , Westra William H. , Mori Masaki , Moon Chulso , Trink Barry , Sidransky David
Published: July 2007

NMDA receptor Type 2B (NMDAR2B) is a candidate TSG first identified in esophageal squamous cell carcinoma (ESCC). To evaluate NMDAR2B methylation in gastric cancer progression, we performed quantitative methylation‐specific PCR (MSP), RT‐PCR and immnunohistochemistry (IHC) in primary gastric tissues and colony formation assays in gastric cancer cell lines. We found that the expression of NMDAR2B was reactivated by the demethylating agent, 5‐aza‐2′‐deoxycytidine, with or without trichostatin A in gastric cancer cell lines. Moreover, inactivation of NMDAR2B was found to be closely correlated with promoter methylation status in gastric cell lines and primary gastric tumors. IHC data also showed that NMDAR2B was specifically expressed in gastric epithelial cells and its expression was diminished or absent in gastric cancer epithelium. Quantitative analysis of NMDAR2B promoter methylation showed 61% (17/28) hypermethylation in primary gastric tumors versus 5% (1/20) in normal gastric tissues from nongastric cancer patients. Forced over‐expression of NMDAR2B in gastric cancer cell lines significantly inhibited cell colony formation. Taken together, the above results suggest that NMDAR2B methylation is a common and important biologically relevant event in gastric cancer progression. © 2007 Wiley‐Liss, Inc.