bluuebunny/crossref_metadata_2025_split huggingface dataset:
Regulation and characterization of the polarity of cells embedded in a reconstructed basement matrix using a three‐dimensional micro‐culture system
Authors: Torisawa Yu‐suke , Nashimoto Yuji , Yasukawa Tomoyuki , Shiku Hitoshi , Matsue Tomokazu 
Published: November 2006

AbstractThree cell lines, that is, the human breast cancer cell line (MCF‐7) and the human mammary epithelial cell line (S‐1) and its malignant form (T4‐2) were embedded in a reconstituted basement membrane (Matrigel) that had 20‐nL pyramid‐shaped silicon microstructures. The proliferative behavior of the MCF‐7 cells was dependent on the surrounding conditions (2‐D, collagen gel, or Matrigel), whereas the respiratory activity of a single cell (Fc) was almost identical under different culture conditions. The Fc value changed with cellular polarity. The Fc value for the S‐1 cells was observed to decrease slightly, whereas that of the T4‐2 cells increased 2 days after cultivation in the microstructures within the Matrigel. However, when the T4‐2 cells were cultured in the presence of tyrphostin AG 1478 (T4‐2 tyr) to inhibit epidermal growth factor (EGF) signaling, the Fc value decreased slightly and remained almost constant for an additional 1 week; this was similar to the behavior of the S‐1 cells. Further, fluorescence images showed that the T4‐2 tyr cells formed polar structures that were similar to those formed by the S‐1 cells whereas the T4‐2 cells did not form such structures. These results indicate that cellular polarity can be assessed by measuring cellular respiratory activity. Biotechnol. Bioeng. 2007;97: 615–621. © 2006 Wiley Periodicals, Inc.
Degradation of supercoiled plasmid DNA within a capillary device
Authors: Meacle F.J. , Zhang H. , Papantoniou I. , Ward J.M. , Titchener‐Hooker N.J. , Hoare M. 
Published: November 2006

AbstractSupercoiled plasmid DNA is susceptible to fluid stress in large‐scale manufacturing processes. A capillary device was used to generate controlled shear conditions and the effects of different stresses on plasmid DNA structure were investigated. Computational fluid dynamics (CFD) analysis was employed to characterize the flow environment in the capillary device and different analytical techniques were used to quantify the DNA breakage. It was found that the degradation of plasmid DNA occurred at the entrance of the capillary and that the shear stress within the capillary did not affect the DNA structure. The degradation rate of plasmids was well correlated with the average elongational strain rate or the pressure drop at the entrance region. The conclusion may also be drawn that laminar shear stress does not play a significant role in plasmid DNA degradation. Biotechnol. Bioeng. 2007; 97: 1148–1157. © 2006 Wiley Periodicals, Inc.
Peutz–Jeghers syndrome and screening for pancreatic cancer
Authors: Latchford A , Greenhalf W , Vitone L J , Neoptolemos J P , Lancaster G A , Phillips R K S 
Published: November 2006

Abstract

Background
Cancer risk, including pancreatic, is high in those with Peutz–Jeghers syndrome (PJS). It has been suggested that such patients should undergo screening for pancreatic cancer.

Methods
The risk of pancreatic cancer in PJS, pancreatic screening and potential screening strategies were reviewed. Cost-effectiveness was assessed according to American Gastroenterology Association guidelines and a risk stratification model proposed by the European Registry of Hereditary Pancreatitis and Familial Pancreatic Cancer.

Results
The risk of pancreatic cancer is increased in PJS but screening would cost over US $350 000 per life saved. Risk stratification reduces cost by $100 000 and costs fall to $50 000 per life saved if deaths from other forms of cancer are avoided.

Conclusion
Screening should be performed only on a research basis to evaluate the benefit and cost-effectiveness in high-risk groups.
Asymmetric Synthesis of 3‐Oxa‐15‐deoxy‐16‐(m‐tolyl)‐17,18,19,20‐tetranorisocarbacyclin and Its Neuroprotective Analogue 15‐Deoxy‐16‐(m‐tolyl)‐17,18,19,20‐tetranorisocarbacyclin Based on the Conjugate Addition–Azoalkene–Asymmetric Olefination Strategy
Authors: van de Sande Marc , Gais Hans‐Joachim 
Published: November 2006

AbstractA fully stereocontrolled synthesis of 3‐oxa‐15‐deoxy‐16‐(m‐tolyl)‐17,18,19,20‐tetranorisocarbacyclin (3‐oxa‐15‐deoxy‐TIC, 7 b) and a formal one of 15‐deoxy‐16‐(m‐tolyl)‐17,18,19,20‐tetranorisocarbacyclin (15‐deoxy‐TIC, 7 a) are described. 15‐Deoxy‐TIC is specific for the neuronal prostacyclin receptor (IP2) and exhibits neuroprotective activities, and the new 3‐oxa‐15‐deoxy‐TIC is expected to be metabolically more stable than 15‐deoxy‐TIC. The syntheses of 7 a and 7 b are based on the convergent conjugate addition–azoalkene–asymmetric olefination strategy. Key building blocks are the readily available bicyclic azoalkene 14 and the alkenylcopper derivative 15. The stereoselective conjugate addition of 15 to 14 gave hydrazone 13, which was stereoselectively converted to the bicyclic ketone 11. The key steps for the construction of the α side chain of 7 a and 7 b and the regioselective introduction of the endocyclic Δ6,6a double bond are: 1) a highly selective asymmetric olefination of ketone 11 with the chiral Horner–Wadsworth–Emmons reagent 28 and 2) a regioselective deconjugation of the α,β‐unsaturated ester (E)‐10 with the chiral lithium amide 29, which gave the β,γ‐unsaturated ester anti‐9 with high selectivity. The homoallylic alcohol 8 served at a late stage as the joint intermediate in the syntheses of 7 a and 7 b. While an etherification of 8 furnished, after hydrolysis and deprotection, 3‐oxa‐15‐deoxy‐TIC, its alkylation afforded alcohol 37, the known precursor for the synthesis of 15‐deoxy‐TIC.
Total Syntheses of Zaragozic Acids A and C by a Carbonyl Ylide Cycloaddition Strategy
Authors: Hirata Yuuki , Nakamura Seiichi , Watanabe Nobuhide , Kataoka Osamu , Kurosaki Takahiro , Anada Masahiro , Kitagaki Shinji , Shiro Motoo , Hashimoto Shunichi 
Published: November 2006

AbstractA carbonyl ylide cycloaddition approach to the squalene synthase inhibitors zaragozic acids A and C is described. The carbonyl ylide precursor 8 was synthesized starting from di‐tert‐butyl D‐tartrate (47) via an eleven‐step sequence involving the regioselective reduction of the mono‐MPM (MPM = 4‐methoxybenzyl) ether 48 with LiBH4 and the diastereoselective addition of sodium tert‐butyl diazoacetate to α‐keto ester 10. The reaction of α‐diazo ester 8 with 3‐butyn‐2‐one (40) in the presence of a catalytic amount of [Rh2(OAc)4] gave the desired cycloadduct 59 as a single diastereomer. The dihydroxylation of enone 59 followed by sequential transformations permitted the construction of the fully functionalized 2,8‐dioxabicyclo[3.2.1]octane core 5. Alkene 79 derived from 5 serves as a common precursor to zaragozic acids A (1) and C (2), since the elongation of the C1 alkyl side chain can be attained by olefin cross‐metathesis, especially under the influence of Blechert's catalyst (85).
Estimation of the optimal brachytherapy utilization rate in the treatment of carcinoma of the uterine cervix
Authors: Thompson Stephen , Delaney Geoff , Gabriel Gabriel Sam , Jacob Susannah , Das Prabir , Barton Michael 
Published: November 2006

AbstractBACKGROUND.Brachytherapy (BT) is an integral part of cervical carcinoma treatment. There have been no attempts to estimate the optimal proportion of new cervical carcinoma cases that should be treated with BT, that is, the optimal rate of brachytherapy utilization (BTU).METHODS.Evidence‐based guidelines and primary evidence were used to construct a BTU tree for carcinoma of the uterine cervix. Searches were performed of the epidemiological literature to ascertain the proportion of patients who fulfilled criteria for BT. The robustness of the model was tested by sensitivity analyses and by peer review. A patterns of care study of BT in New South Wales for 2003 was conducted, and actual BTU for cervical carcinoma determined. The differences between optimal and actual rates of BTU were assessed.RESULTS.The optimal cervical carcinoma BTU was 49% (range, 42% to 50%). In New South Wales in 2003, actual BTU was only 30% of 256 cervical carcinoma patients. The major discrepancy was for FIGO stage IB‐IIA disease, where there was an underutilization of BT, estimated to be 15% actual use compared with 47% optimal use. In Surveillence, Epidemiology, and End Results (SEER) areas, there was underutilization for stage IB‐IIA (22% actual BTU versus 47% optimal BTU) and for stage IIB‐IVA (54% actual BTU versus 100% optimal BTU).CONCLUSIONS.BT for cervical carcinoma is underutilized in New South Wales and in SEER areas. The authors' model of optimal BTU can be used as a quality assurance tool to provide an evidence‐based benchmark against which actual patterns of practice can be measured. The model can also be used to help determine adequacy of BT resource allocation. Cancer 2006. © 2006 American Cancer Society.
Using a virtual machine to protect sensitive Grid resources
Authors: Zhao Xin , Borders Kevin , Prakash Atul 
Published: November 2006

AbstractMost Grid systems rely on their operating systems (OSs) to protect their sensitive files and networks. Unfortunately, modern OSs are very complex and it is difficult to completely avoid intrusions. Once intruders compromise the OS and gain system privilege, they can easily disable or bypass the OS security protections. This paper proposes a secure virtual Grid system, SVGrid, to protect sensitive system resources. SVGrid works by isolating Grid applications in Grid virtual machines. The Grid virtual machines' filesystem and network services are moved into a dedicated monitor virtual machine. All file and network accesses are forced to go through this monitor virtual machine, where SVGrid checks request parameters and only accepts the requests that comply with security rules. Because SVGrid enforces security policy in the isolated monitor virtual machine, it can continue to protect sensitive files and networks even if a Grid virtual machine is compromised. We tested SVGrid against attacks on Grid virtual machines. SVGrid was able to prevent all of them from accessing files and networks maliciously. We also evaluated the performance of SVGrid and found that performance cost was reasonable considering the security benefits of SVGrid. Furthermore, the experimental results show that the virtual remote procedure call mechanism proposed in this paper significantly improves system performance. Copyright © 2006 John Wiley & Sons, Ltd.
Relative autonomous accounting for peer‐to‐peer Grids
Authors: Santos Robson , Andrade Alisson , Cirne Walfredo , Brasileiro Francisco , Andrade Nazareno 
Published: November 2006

AbstractHere we present and evaluate relative accounting, an autonomous accounting scheme that provides accurate results even when the parties (consumer and provider) do not trust each other. Relative accounting relies on the observed relative performance amongst the parties. As such, the basic requirement to use it is that resource consumers must also be resource providers. Relative accounting is totally autonomous in the sense that it uses only local information, i.e. there is no exchange of information between the parties. This allows for the deployment of the autonomous accounting without requiring any sort of identification infrastructure, such as certificate authorities. Not requiring trust or sophisticated infrastructure makes relative accounting a perfect fit for peer‐to‐peer Grids, which aim to scale much further than traditional Grids by allowing free unidentified entry into the Grid. Our results show that relative accounting performs very close to a perfect accounting, whose implementation is infeasible in most systems, including those we target. Relative accounting was developed to work with OurGrid, a peer‐to‐peer Grid in production since December 2004, but it can also be used in other peer‐to‐peer Grids. Copyright © 2006 John Wiley & Sons, Ltd.
GRAND: toward scalability in a Grid environment
Authors: Vargas Patrícia Kayser , Dutra Inês C. , do Nascimento Vinícius D. , Santos Lucas A. S. , da Silva Luciano C. , Geyer Cláudio F. R. , Schulze Bruno 
Published: November 2006

AbstractOne of the challenges in Grid computing research is to provide a means to automatically submit, manage, and monitor applications whose main characteristic is to be composed of a large number of tasks. The large number of explicit tasks, generally placed on a centralized job queue, can cause several problems: (1) they can quickly exhaust the memory of the submission machine; (2) they can deteriorate the response time of the submission machine due to these demanding too many open ports to manage remote execution of each of the tasks; (3) they may cause network traffic congestion if all tasks try to transfer input and/or output files across the network at the same time; (4) they make it impossible for the user to follow execution progress without an automatic tool or interface; (5) they may depend on fault‐tolerance mechanisms implemented at application level to ensure that all tasks terminate successfully. In this work we present and validate a novel architectural model, GRAND (Grid Robust ApplicatioN Deployment), whose main objective is to deal with the submission of a large numbers of tasks. Copyright © 2006 John Wiley & Sons, Ltd.
Distributed and dynamic self‐scheduling of parallel MPI Grid applications
Authors: Nascimento Aline P. , Sena Alexandre C. , Boeres Cristina , Rebello Vinod E. F. 
Published: November 2006

AbstractThe execution of distributed applications on the Grid is already a reality. However, as both the number of applications grow and Grids increase in scale, the efficient utilization of the available but shared heterogeneous resources will become increasingly essential to the Grid's successful maturity. Furthermore, it is unclear whether existing Grid management systems are capable of meeting this challenge. The EasyGrid middleware is a hierarchically distributed application management system (AMS) that is embedded into MPI applications to autonomously orchestrate their execution efficiently in computational Grids. The overhead of employing a distinct AMS to make each application system aware brings at least two benefits. First, the adopted policies can be tailored to the specific needs of each application, leading to improved performance. Second, distributing the management effort among executing applications makes Grid management more scalable. This article focuses on scheduling policies of an AMS for a particular class of application, describing a low intrusion implementation of a hybrid scheduling strategy designed to elicit good performance even in dynamic environments such as Grids. Using application‐specific scheduling policies, near‐optimal runtimes highlight the advantages of self‐scheduling when executing one or more system aware applications on a Grid. Copyright © 2006 John Wiley & Sons, Ltd.
Towards increased expressiveness in service level agreements
Authors: Yarmolenko Viktor , Sakellariou Rizos 
Published: November 2006

AbstractThe aim of this paper is to argue for the benefits of increased expressiveness in service level agreements (SLAs). Such benefits may be obtained from the use of analytical expressions to specify a SLA's agreement terms as functions and not as variable or constant values or ranges. The main idea behind this thinking is that functions may contain variables defined in the SLA or be drawn from the known set of reference variables, such as wall‐clock time, job start time, current bandwidth of the resource, etc. Experiences and conclusions drawn are in the context of SLA‐based job management systems. We demonstrate that the use of analytical expressions in SLAs can potentially reduce the overheads associated with job renegotiation and/or reduce the number of failed agreements. Copyright © 2006 John Wiley & Sons, Ltd.
Practical experience of run‐time link reconfiguration in a multi‐transputer machine
Authors: Jones Peter , Murta Alan 
Published: November 2006

AbstractThe paper describes a novel message passing regime for multi‐processor machines using transputers. The development of this facillity was motivated by the disparity between the interconnect available in transputer machines and the arbitary degree of interconnect implicit in the underlying CSP model of computation. The technique presented involves the alteration of the link topology of the machine during run‐time, under the contrl of executing user code. Performance evaluation has been undertaken and the results are given. In particular, it is shown how run‐time reconfiguration leads to performance enhancement for some classes of problems.
Load balancing and Poisson equation in a graph
Authors: Boillat J. E. 
Published: November 2006

AbstractWe present a fully distributed dynamic load balancing algorithm for parallel MIMD architectures. The algorithm can be described as a system of identical parallel processes, each running on a processor of an arbitrary interconnected network of processors. We show that the algorithm can be interpreted as a Poisson (heath) equation in a graph. This equation is analysed using Markov chain techniques and is proved to converge in polynomial time resulting in a global load balance. We also discuss some important parallel architectures and interconnection schemes such as linear processor arrays, tori, hypercubes, etc. Finally we present two applications where the algorithm has been successfully embedded (process mapping and molecular dynamic simulation).
Product label inspection using transputers
Authors: Mirmehdi Majid 
Published: November 2006

AbstractA product label inspection system implemented on a transputer network is described. Two data routing algorithms are considered, one for a general M × N array and one for a customized setup of transputers. Data transfer results for various image sizes are provided. Reliable and fast label inspection algorithms are described for rectangular, acute‐angled and oval‐shaped product labels, and their implementation on both the general and the customized networks are discussed. Simulated test results are provided to illustrate the present capability of the system for inspecting large numbers of labels per second.
Particle flow instrumentation
Authors: Mills E. , O'Neill B. C. 
Published: November 2006

AbstractThis paper describes the development of a real‐time particle flow meter for pneumatic conveyance systems. The subject is approached by a brief overview of the pneumatic transportation process and method of particle detection, moving to the decisions taken on the choice of host processor system, the design of the final system and the results obtained to date.The application of this work is not confined to commercial pneumatically conveyed products, such as epoxy powder paint for electrostatic paint spraying; the measurement system itself is of interest to the CEGB for determining the efficiency of their electrostatic precipitators and exhaust‐gas‐driven turbine protection.
A transputer radar ESM data processor
Authors: Beton Richard , Kingdon James , Upstill Colin 
Published: November 2006

AbstractA parallel radar ESM data processing system using occam and transputers is presented. High‐level software solutions for radar ESM to run on multiple transputer systems were investigated, to achieve high throughput cost‐effectively. The system is primarily a vehicle to support further algorithm research and to permit benchmarking; it is expandable and flexible, and can be modified to run on different numbers of processors with almost linear improvement in performance. The architecture has a hybrid pipelined structure; the topology within each stage of a concurrent processor pipeline is chosen to optimize the processing and communications for the required function. A novel technique is described for improving the load balancing of such algorithmically decomposed parallel systems.
The Radon transform on a dynamically switched transputer network
Authors: Hall G. , Terrell T. J. , Murphy L. M. 
Published: November 2006

AbstractPreviously reported work resulted in a transputer tree network using thirty tramputers to perform the Radon transform. The Radon transform was used to enhance linear features in noisy synthetic aperture radar images. The work presented here describes modification of the transputer network by the addition of INMOS B004 link switches, and controlling T222 transputer. The tree configuration is replaced such that link switches now dynamically switch between the image data source transputer (farmer) and the transputers which perform the calculations (workers). It is shown that this arrangement is more cost‐effective since the worker transputers are all relieved of their data‐routing role. The paper Includes a comparison of the previous tree network with the new switched network, and presents results for both techniques.
MARVIN and TINA: A multiprocessor 3‐D vision system
Authors: Rygol Michael , Pollard Stephen , Brown Chris 
Published: November 2006

AbstractWe describe a working multi‐transputer stereo vision system which exploits various forms of parallelism in a number of visual competences upon a specialized hardware architecture that provides distributed video datapaths to the processor array. We exploit stereo and spatial parallelism to recover 3‐D scene descriptions from passive stereo vision. To recognize and recover the positions of modelled objects, we exploit featural parallelism at both the object and sub‐object level. We also describe a real‐time object‐tracking algorithm that exploits featural parallelism in the concurrent tracking of a set of object features.These competences have been integrated into a general‐purpose architecture and we present some performance results and descriptions of the use of this vision engine in two application domains.
Distributing gate‐level digital timing simulation over arrays of transputers
Authors: Wood Kenneth R. 
Published: November 2006

AbstractContinuing advances in VLSI fabrication technology are allowing circuit designs to become more and more complex and are thereby fuelling the need for ever‐faster digital simulators. In this paper, we investigate a multi‐transputer‐based method for speeding up gate‐level digital timing simulation, the acknowledged 'workhorse' of the digital circuit design verification process. In particular, we describe a variant of the basic conservative method for distributed discrete‐event simulation and we present PARSIM, a gate‐level digital timing simulator which is based on this method and which runs on arrays of transputers. Preliminary results on small transputer arrays demonstrate good speed‐ups for bitslice partitions of circuits with regular structure, including supralinear speed‐ups for a large (1664‐gate) circuit. Although these results are encouraging, poor results for less‐than‐ideal partitions of our test circuits suggest that we require an improvement in the efficiency of deadlock resolution and/or a means of automated optimized partitioning before PARSIM can be used as a practical tool for speeding up gate‐level simulation.
Experiments with a transputer‐based parallel graph reduction machine
Authors: Rabhi Fethi A. , Manson Gordon A. 
Published: November 2006

AbstractThis paper is concerned with the implementation of functional languages on a parallel architecture, using graph reduction as a model of computation. Parallelism in such systems is automatically derived by the compiler but a major problem is the fine granularity, illustrated in Divide‐and‐Conquer problems at the leaves of the computational tree. The paper addresses this issue and proposes a method based on static analysis combined with run‐time tests to remove the excess in parallelism. We report experiments on a prototype machine, simulated on several connected INMOS transputers. Performance figures show the benefits in adopting the method and the difficulty of automatically deriving the optimum partitioning due to differences among the problems.