bluuebunny/crossref_metadata_2025 huggingface dataset:
Yannis Ioannidis speaks out on database research funding in Europe, the importance of being uncertain, teaching as show business, the history of histograms, and more
Authors: Winslett Marianne
Published: April 2007

Welcome to this installment of ACM SIGMOD Record's series of interviews with distinguished members of the database community. I'm Marianne Winslett, and today we are at the SIGMOD 2006 conference in Chicago. I have here with me Yannis Ioannidis, who is a professor of informatics and telecommunication at the University of Athens. Before that, he was a professor for many years at the University of Wisconsin in Madison. Yannis's research focuses on query optimization, digital libraries, and management of scientific data. Yannis is an ACM Fellow, has won numerous teaching awards, and received the VLDB 10 Year Best Paper Award. He is the Vice-Chair of SIGMOD, and his PhD is from the University of California at Berkeley. So, Yannis, welcome!
Flow in games (and everything else)
Authors: Chen Jenova
Published: April 2007

A well-designed game transports its players to their personal Flow Zones, delivering genuine feelings of pleasure and happiness.
View from the floor
Authors: Hefferan Patrick M.
Published: April 2007

Over 70 exhibitors participated in this year's Design Automation Conference. Everyone from AT&T to Zycad was clustered together in the exhibit hall of Caesar's Palace. And although Hillel Ofek's keynote address lamented the lack of new ideas, there were several emerging trends and new commercial product families evident from the offerings on the exhibit floor. As was true last year, there was a growing trend toward consolidation in the CAD industry as smaller companies are acquired by larger, old-line companies. Also, several new technologies emerged as commercially viable products, including silicon compilers, new CAD hosts, special-purpose hardware accelerators, and a new family of PCB thermal analysis utilities. And of course a number of companies announced enhancements and improvements in their current product line or integrated elements of each others products.
Some comments on Denning's principle of optimality
Authors: Pomeranz John E.
Published: April 2007

Denning and others have proposed a page replacement strategy and asked whether it is generally optimal in the sense of minimizing the expected number of faults.
ACM/SIGOPS workshop on system performance evaluation
Authors: Swenson J. Richard
Published: April 2007

An ACM/SIGOPS Workshop on System Performance Evaluation was held on April 5-7 1971 at Harvard University.
Harmful dogmas in fault tolerant distributed computing
Authors: Charron-Bost Bernadette , Schiper André
Published: April 2007

Consensus is a central problem in fault tolerant distributed computing. A vast number of (positive and negative) results for consensus in various system models have been established. In this paper we isolate three features that all these system models share, and we show that inappropriate modelling choices have led to overcomplicate the approaches to studying the consensus problem, thus yielding too restrictive solutions for real systems.

It is hard to question these modelling choices, as they have gained the status of dogmas. Nevertheless, we propose a simpler and more natural approach that allows us to get rid of these dogmas, and to handle all types of benign fault, be it static or dynamic, permanent or transient, in a unified framework.
The challenge of parallel function evaluation
Authors: Dunham Charles B.
Published: April 2007

A topic that does not seem to have been considered is how to do function evaluations in parallel, that is, how to evaluate a mathematical function, eg. exp, for several different arguments simultaneously on a machine with parallel processors eg. ILLIAC IV: that machine had 64 processors, whose reaction to a (parallel) command from the master computer was either to execute or (on a condition) to decline to execute the instruction.
Book review: Using Excel: Macintosh Versionby Christopher Van Buren (Que Corporation)
Authors: Bash Charles W.
Published: April 2007

This book attempts to provide a complete coverage of Microsoft Excel, Version 2.2 in a fashion that the novice can understand. It is the reviewer's opinion that the result is not bad, but that a subject this broad might need more exposition than a single book can achieve.
Book review: Oracle Programmer's Guide by David Pepin (Que Corporation)
Authors: Bash Charles W.
Published: April 2007

These chapters are not accidental, they are very necessary for the user. Oracle for the PC is a direct clone of Oracle for the VAX, IBM mainframe or any other copy that they have. This system is designed to handle multiple users, from multiple terminals, all at the same time. It was designed with the intention that a professional data base administrator would run and manage it. Thus it is not for the faint hearted, or casual user.
Book review: 1-2-3 Database Techniques by Dick Anderson and Bill Neil (Que Corporation, 1989)
Authors: Carter George
Published: April 2007

This book's objective is to provide users of 1-2-3 (versions 2.01, 2.2 & 3) with a tutorial which teachers 1-2-3 database design using a variety of 1-2-3's commands and functions - some made specifically for database management. Authors, Anderson and Weil, provide just enough of the database fundamentals for beginners (i. e., someone already having mastered 1-2-3 but lack experience with database applications) as well as advanced techniques (ex.: normalization) for intermediate and advanced database users and/or designers.
Book review: Using C, Lee Atkinson & Mark Atkinson (Que, 1990)
Authors: Cigas John
Published: April 2007

Using C
is a good book for intermediate and experienced programmers who want to learn about ANSI C. It covers the essential topics of C, including functions, pointers, I/O, and separate compilation, as well as the standard topics of operators, expressions, control flow, etc. In addition, it illustrates all the features of ANSI C, and includes a section on C++. The text includes several complete C programs that are compatible with the major C compilers for DOS. However, there is no companion disk, nor are there specific exercises on which the user can hone his/her programming skills.
Object-oriented simulation of CSMA protocols
Authors: Saiedian Hossein
Published: April 2007

We describe the benefits of an object-oriented approach to simulation and describe an object-oriented approach to the simulation of a class of network protocols known as CSMA and discuss the implications of the simulation model with respect to a network of personal computers. A valuable aspect of the model presented here is its similarity to actual networks. While the model reflects three layers of typical network (namely the physical, data link, and the application layers), relative case with which the objects modelling these layers can be modified makes it possible to examine other network characteristics. Additional objects can be added to model other layers in a network without disturbing or requiring detailed knowledge of the existing objects.
Versatile visual programming environment for scientific applications
Authors: Rijnders F. M. , Spoelder H. J. W. , Corten E. P. M. , Ullings A. H. , Groen F. C. A.
Published: April 2007

We report on a visual programming environment designed to make and execute programs using already existing procedures written in some third generation language. The utilization of a client/server model combined with the dataflow principle makes this visual programming environment capable of networkwide operations. This feature can be used to elegantly incorporate dedicated hardware like data-acquisition devices and/or number crunchers into one visual program. The combination of these features offers interesting possibilities in the field of e.g. parallel processing and data-acquisition combined with number crunching thus making this tool very apt for the physics community.
Algorithm for Julian dates
Authors: Branham Richard L.
Published: April 2007

C functions are given that allow one to calculate a Julian day number for a day, month, and year on the Julian calendar, take a Julian day number and convert it to a day, month, and year on the Julian calendar, and find the day of the week that corresponds to a day, month, and year on the Julian calendar.
A compilation of automatic differentiation tools presented at the 1995 international convention on industrial and applied mathematics, Hamburg
Authors: Bischof Chris , Dilley Fred
Published: April 2007

This document was compiled for the minisymposium on automatic differentiation tools presented at the 1995 International Convention on Industrial and Applied Mathematics, Hamburg. The document was compiled by Chris Bischof and Fred Dilley of Argonne National Laboratory with contributions by Mike Bartholomew-Biggs, Stephen Brown, Alan Carle, Bruce Christianson, David Cowey, Frederic Eyssette, David M. Gay, Ralf Giering, Andreas Griewank, Jim Horwedel, Peyvand Khademi, K. Kubota, Andrew Mauer, Michael B. Monagan, John Pryce, John Reid, Andreas Rhodin, Nicole Rostaing-Schmidt, and Jean Utke.
Are orthogonal transformations worthwhile for least squares problems?
Authors: Branham Richard L
Published: April 2007

Orthogonal transformations are important in many areas of numerical analysis. Even though they may be used for the solution of large least squares systems, their suitability for this task has been exaggerated. For most problems normal equations are adequate and computationally less time consuming.
A simple virtual machine
Authors: Kelsh James P , Hansen John C
Published: April 2007

Many computer science classes begin with a discussion of how a computer performs certain actions. In an introductory survey of computers, this frequently involves demonstrating some application program. A first course for majors in computer science is likely to discuss high-level programming languages and compare them to the assembly language of some mainframe. A course in system programming is likely to provide examples of assembly language code and relocatable object code before introducing assemblers, linkers, and loaders. The authors have observed certain drawbacks in some of the familiar approaches.
Should ACM or Sigsmall/PC publish courseware?
Authors: Press Larry
Published: April 2007

Personal computers with high-bandwidth displays, optical storage, and voice output devices offer a significant advantage for computer assisted instruction, and they will eventually become an integral part of the university curriculum. Since many of our members are teachers, perhaps ACM or our SIG should be involved in the refereeing, publishing or distribution of courseware. This paper speculates on publication options and criteria.
Artificial neural network technology
Authors: Yoon B. L.
Published: April 2007

The Defense Advanced Research Projects Agency (DARPA) has initiated a major new program in Artificial Neural Network Technology. This technology may lead to solution of complex information processing and autonomous control problems (including problems that require real-time processing and response) that have persistently evaded solution by conventional techniques. If its promise can be realized, artificial neural network technology will provide powerful tools for a broad range of military applications, including sophisticated systems for target recognition and tracking and for real-time guidance.
Ghrelin and its unacylated isoform stimulate the growth of adrenocortical tumor cells via an anti-apoptotic pathway
Authors: Delhanty P. J. D. , van Koetsveld P. M. , Gauna C. , van de Zande B. , Vitale G. , Hofland L. J. , van der Lely A. J.
Published: April 2007

Ghrelin is expressed in normal human adrenocortical cells and induces their proliferation through growth hormone secretagogue receptor 1a (GHS-R1a). Consequently, it was of interest to us to determine whether acylated ghrelin and its predominant serum isoform, unacylated ghrelin, also act as factors for adrenocortical carcinoma cell growth. To examine a potential ghrelin-regulated system in adrenocortical tumors, we measured proliferative effects of acylated and unacylated ghrelin in the adrenocortical carcinoma cell lines SW-13 and NCI-H295R. We also examined the expression of ghrelin, GHS-R1a, and corticotrophin-releasing factor receptor 2 (CRF-R2). Acylated and unacylated ghrelin in the nanomolar range dose-dependently induced adrenocortical cell growth up to 200% of untreated controls, as measured by thymidine uptake and WST1 assay. The proliferative effects of acylated and unacylated ghrelin in SW-13 cells was blocked by [d-Lys3]growth hormone-releasing peptide 6 (GHRP6), but a CRF-R2 antagonist had no effect on unacylated ghrelin growth stimulation. Cell cycle analysis suggests that acylated and unacylated ghrelin suppress the sub-G0/apoptotic fraction by up to 50%. Measurement of DNA fragmentation and caspase-3 and -7 activity in SW-13 cells confirmed that acylated and unacylated ghrelin suppress apoptotic rate. SW-13 cells express preproghrelin mRNA and secrete ghrelin, and [d-Lys3]GHRP6 suppresses their basal proliferation rate, strongly suggesting that ghrelin could act as an auto/paracrine growth factor. Acylated and unacylated ghrelin are potential auto/paracrine factors acting through an antiapoptotic pathway to stimulate adrenocortical tumor cell growth. Unacylated ghrelin-stimulated growth is suppressed by an antagonist of GHS-R1a, suggesting either that unacylated ghrelin is acylated before its action or that ghrelin, unacylated ghrelin, and [d-Lys3]GHRP-6 bind to a novel receptor in these cells.
Interval Coding. I. Burst Interspike Intervals as Indicators of Stimulus Intensity
Authors: Oswald Anne-Marie M. , Doiron Brent , Maler Leonard
Published: April 2007

Short interspike intervals such as those that occur during burst firing are hypothesized to be distinct features of the neural code. Although a number of correlations between the occurrence of burst events and aspects of the stimulus have been identified, the relationship between burst characteristics and information transfer is uncertain. Pyramidal cells in the electrosensory lobe of the weakly electric fish, Apteronotus leptorhynchus, respond to dynamic broadband electrosensory stimuli with bursts and isolated spikes. In the present study, we mimic synaptic input during sensory stimulation by direct stimulation of electrosensory pyramidal cells with broadband current in vitro. The pyramidal cells respond to this stimulus with burst interspike intervals (ISIs) that are reliably and precisely correlated with the intensity of stimulus upstrokes. We found burst ISIs must differ by a minimum of 2 ms to discriminate, with low error, differences in stimulus intensity. Based on these results, we define and quantify a candidate interval code for the processing of sensory input. Finally, we demonstrate that interval coding is restricted to short ISIs such as those generated in burst events and that the proposed interval code is distinct from rate and timing codes.
Amplification of MDS1/EVI1 and EVI1, Located in the 3q26.2 Amplicon, Is Associated with Favorable Patient Prognosis in Ovarian Cancer
Authors: Nanjundan Meera , Nakayama Yasuhisa , Cheng Kwai Wa , Lahad John , Liu Jinsong , Lu Karen , Kuo Wen-Lin , Smith-McCune Karen , Fishman David , Gray Joe W. , Mills Gordon B.
Published: April 2007

Increased copy number involving chromosome 3q26 is a frequent and early event in cancers of the ovary, lung, head and neck, cervix, and BRCA1 positive and basal breast cancers. The p110α catalytic subunit of phosphoinositide-3-kinase (PI3KCA) and protein kinase Cι (PKCι) have previously been shown as functionally deregulated by 3q copy number increase. High-resolution array comparative genomic hybridization of 235 high-grade serous epithelial ovarian cancers using contiguous bacterial artificial chromosomes across 3q26 delineated an ∼2 Mb–wide region at 3q26.2 encompassing PDCD10 to MYNN (chr3:168722613-170908630). Ecotropic viral integration site-1 (EVI1) and myelodysplastic syndrome 1 (MDS1) are located at the center of this region, and their DNA copy number increases are associated with at least 5-fold increased RNA transcript levels in 83% and 98% of advanced ovarian cancers, respectively. Moreover, MDS1/EVI1 and EVI1 protein levels are increased in ovarian cancers and cancer cell lines. EVI1 and MDS1/EVI1 gene products increased cell proliferation, migration, and decreased transforming growth factor-β–mediated plasminogen activator inhibitor-1 promoter activity in ovarian epithelial cells. Intriguingly, the increases in EVI1 DNA copy number and MDS1/EVI1 transcripts are associated with improved patient outcomes, whereas EVI1 transcript levels are associated with a poor patient survival. Thus, the favorable patient prognosis associated with increased DNA copy number seems to be as a result of high-level expression of the fusion transcript MDS1/EVI1. Collectively, these studies suggest that MDS1/EVI1 and EVI1, previously implicated in acute myelogenous leukemia, contribute to the pathophysiology of epithelial ovarian cancer. [Cancer Res 2007;67(7):3074–84]
Tagging Single Nucleotide Polymorphisms in Cell Cycle Control Genes and Susceptibility to Invasive Epithelial Ovarian Cancer
Authors: Gayther Simon A. , Song Honglin , Ramus Susan J. , Kjaer Susan Krüger , Whittemore Alice S. , Quaye Lydia , Tyrer Jonathan , Shadforth Danielle , Hogdall Estrid , Hogdall Claus , Blaeker Jan , DiCioccio Richard , McGuire Valerie , Webb Penelope M. , Beesley Jonathan , Green Adele C. , Whiteman David C. ,   The Australian Ovarian Cancer Study Group,   The Australian Cancer Study (Ovarian Cancer), Goodman Marc T. , Lurie Galina , Carney Michael E. , Modugno Francesmary , Ness Roberta B. , Edwards Robert P. , Moysich Kirsten B. , Goode Ellen L. , Couch Fergus J. , Cunningham Julie M. , Sellers Thomas A. , Wu Anna H. , Pike Malcolm C. , Iversen Edwin S. , Marks Jeffrey R. , Garcia-Closas Montserrat , Brinton Louise , Lissowska Jolanta , Peplonska Beata , Easton Douglas F. , Jacobs Ian , Ponder Bruce A.J. , Schildkraut Joellen , Pearce C. Leigh , Chenevix-Trench Georgia , Berchuck Andrew , Pharoah Paul D.P. ,   on behalf of the Ovarian Cancer Association Consortium
Published: April 2007

High-risk susceptibility genes explain <40% of the excess risk of familial ovarian cancer. Therefore, other ovarian cancer susceptibility genes are likely to exist. We have used a single nucleotide polymorphism (SNP)–tagging approach to evaluate common variants in 13 genes involved in cell cycle control—CCND1, CCND2, CCND3, CCNE1, CDK2, CDK4, CDK6, CDKN1A, CDKN1B, CDKN2A, CDKN2B, CDKN2C, and CDKN2D—and risk of invasive epithelial ovarian cancer. We used a two-stage, multicenter, case-control study. In stage 1, 88 SNPs that tag common variation in these genes were genotyped in three studies from the United Kingdom, United States, and Denmark (∼1,500 cases and 2,500 controls). Genotype frequencies in cases and controls were compared using logistic regression. In stage 2, eight other studies from Australia, Poland, and the United States (∼2,000 cases and ∼3,200 controls) were genotyped for the five most significant SNPs from stage 1. No SNP was significant in the stage 2 data alone. Using the combined stages 1 and 2 data set, CDKN2A rs3731257 and CDKN1B rs2066827 were associated with disease risk (unadjusted P trend = 0.008 and 0.036, respectively), but these were not significant after adjusting for multiple testing. Carrying the minor allele of these SNPs was found to be associated with reduced risk [OR, 0.91 (0.85–0.98) for rs3731257; and OR, 0.93 (0.87–0.995) for rs2066827]. In conclusion, we have found evidence that a single tagged SNP in both the CDKN2A and CDKN1B genes may be associated with reduced ovarian cancer risk. This study highlights the need for multicenter collaborations for genetic association studies. [Cancer Res 2007;67(7):3027–35]
Histone Deacetylase 2 Modulates p53 Transcriptional Activities through Regulation of p53-DNA Binding Activity
Authors: Harms Kelly Lynn , Chen Xinbin
Published: April 2007

Histone deacetylase (HDAC) inhibitors are emerging as promising cancer therapeutics. HDAC inhibitors have been found to induce cellular activities that are strikingly similar to p53-mediated responses to genotoxic stress. For example, HDAC inhibitors induce cell cycle arrest, apoptosis, and cellular senescence. Because at least 11 HDACs are affected by the current HDAC inhibitors, the HDAC critical for tumor cell survival and proliferation remains unknown. Thus, we sought to characterize the distinct roles of HDACs in the p53 pathway. Through the use of stable MCF7 cell lines which inducibly express short hairpin RNA targeting HDAC2, we found that HDAC2 plays important roles in the p53 pathway. Specifically, we found that knockdown of HDAC2 inhibited cellular proliferation in a dose-dependent manner which was also partly p53-dependent. Furthermore, knockdown of HDAC2 induced cellular senescence. Importantly, we found that knockdown of HDAC2 enhanced p53-dependent trans-repression and trans-activation of a subset of target genes. We found that the enhancement was due to increased p53-DNA binding activity but not alterations in p53 stability or posttranslational modification(s). Thus, for the first time, our data suggest that HDAC inhibitors function through the p53 pathway, at least in part, by activating p53-DNA binding activity. [Cancer Res 2007;67(7):3145–52]
Activation of a novel ataxia-telangiectasia mutated and Rad3 related/checkpoint kinase 1–dependent prometaphase checkpoint in cancer cells by diallyl trisulfide, a promising cancer chemopreventive constituent of processed garlic
Authors: Herman-Antosiewicz Anna , Stan Silvia D. , Hahm Eun-Ryeong , Xiao Dong , Singh Shivendra V.
Published: April 2007

Diallyl trisulfide (DATS), a cancer chemopreventive constituent of garlic, inhibits growth of cancer cells by interfering with cell cycle progression, but the mechanism is not fully understood. Here, we show the existence of a novel ataxia-telangiectasia mutated and Rad3 related (ATR)/checkpoint kinase 1 (Chk1)–dependent checkpoint partially responsible for DATS-mediated prometaphase arrest in cancer cells, which is different from the recently described γ irradiation–induced mitotic exit checkpoint. The PC-3 human prostate cancer cells synchronized in prometaphase by nocodazole treatment and released to DATS-containing medium remained arrested in prometaphase, whereas the cells released to normal medium exited mitosis and resumed cell cycle. The mitotic arrest was maintained even after 4 h of culture of DATS-treated cells (4-h treatment) in drug-free medium. The DATS-arrested mitotic cells exhibited accumulation of anaphase-promoting complex/cyclosome (APC/C) substrates cyclin A and cyclin B1 and hyperphosphorylation of securin, which was accompanied by increased phosphorylation of the APC/C regulatory subunits Cdc20 and Cdh1. The DATS-mediated accumulation of cyclin B1 and hyperphosphorylation of securin, Cdc20, and Cdh1 were partially but markedly attenuated by knockdown of Chk1 or ATR protein. The U2OS osteosarcoma cells expressing doxycycline-inducible kinase dead ATR were significantly more resistant not only to DATS-mediated prometaphase arrest but also to the accumulation of cyclin B1 and hyperphosphorylation of securin, Cdc20, and Cdh1 compared with cells expressing wild-type ATR. However, securin protein knockdown failed to rescue cells from DATS-induced prometaphase arrest. In conclusion, the present study describes a novel signaling pathway involving ATR/Chk1 in the regulation of DATS-induced prometaphase arrest. [Mol Cancer Ther 2007;6(4):1249–61]
H2AX phosphorylation marks gemcitabine-induced stalled replication forks and their collapse upon S-phase checkpoint abrogation
Authors: Ewald Brett , Sampath Deepa , Plunkett William
Published: April 2007

Gemcitabine is a nucleoside analogue that is incorporated into replicating DNA, resulting in partial chain termination and stalling of replication forks. The histone variant H2AX is phosphorylated on Ser139 (γ-H2AX) and forms nuclear foci at sites of DNA damage. Here, we characterize the concentration- and time-dependent phosphorylation of H2AX in response to gemcitabine-induced stalled replication forks. The number of γ-H2AX foci increased with time up to 2 to 6 h after exposure to gemcitabine, whereas longer exposures did not cause greater phosphorylation or increase cell death. The percentage of γ-H2AX–positive cells increased with concentrations of gemcitabine up to 0.1 μmol/L, and γ-H2AX was most evident in the S-phase fraction. Phosphorylation of ataxia-telangiectasia mutated (ATM) on Ser1981 was also associated with S-phase cells and colocalized in the nucleus with phosphorylated H2AX foci after gemcitabine exposure. Chemical inhibition of ATM, ATM- and Rad3-related, and DNA-dependent protein kinase blocked H2AX phosphorylation. H2AX and ATM phosphorylation were associated with inhibition of DNA synthesis, S-phase accumulation, and activation of the S-phase checkpoint pathway (Chk1/Cdc25A/cyclin-dependent kinase 2). Exposure of previously gemcitabine-treated cultures to the Chk1 inhibitor 7-hydroxystaurosporine (UCN-01) caused a 10-fold increase in H2AX phosphorylation, which was displayed as an even pan-nuclear staining. This increased phosphorylation was not due to apoptosis-induced DNA fragmentation and was associated with the S-phase fraction and decreased reproductive viability. Thus, H2AX becomes phosphorylated and forms nuclear foci in response to gemcitabine-induced stalled replication forks, and this is greatly increased upon checkpoint abrogation. [Mol Cancer Ther 2007;6(4):1239–48]
MAP-ing glioma invasion: Mitogen-activated protein kinase kinase 3 and p38 drive glioma invasion and progression and predict patient survival
Authors: Demuth Tim , Reavie Linsey B. , Rennert Jessica L. , Nakada Mitsutoshi , Nakada Satoko , Hoelzinger Dominique B. , Beaudry Christian E. , Henrichs Amanda N. , Anderson Eric M. , Berens Michael E.
Published: April 2007

Although astrocytic brain tumors do not metastasize systemically, during tumorigenesis glioma cells adopt an invasive phenotype that is poorly targeted by conventional therapies; hence, glioma patients die of recurrence from the locally invasive tumor population. Our work is aimed at identifying and validating novel therapeutic targets and biomarkers in invasive human gliomas. Transcriptomes of invasive glioma cells relative to stationary cognates were produced from a three-dimensional spheroid in vitro invasion assay by laser capture microdissection and whole human genome expression microarrays. Qualitative differential expression of candidate invasion genes was confirmed by quantitative reverse transcription-PCR, clinically by immunohistochemistry on tissue microarray, by immunoblotting on surgical specimens, and on two independent gene expression data sets of glial tumors. Cell-based assays and ex vivo brain slice invasion studies were used for functional validation. We identify mitogen-activated protein kinase (MAPK) kinase 3 (MKK3) as a key activator of p38 MAPK in glioma; MKK3 activation is strongly correlated with p38 activation in vitro and in vivo. We further report that these members of the MAPK family are strong promoters of tumor invasion, progression, and poor patient survival. Inhibition of either candidate leads to significantly reduced glioma invasiveness in vitro. Consistent with the concept of synthetic lethality, we show that inhibition of invasion by interference with these genes greatly sensitizes arrested glioma cells to cytotoxic therapies. Our findings therefore argue that interference with MKK3 signaling through a novel treatment combination of p38 inhibitor plus temozolomide heightens the vulnerability of glioma to chemotherapy. [Mol Cancer Ther 2007;6(4):1212–22]
Investigation of Surface Duct Conditions over Istanbul, Turkey
Authors: Mentes ŞSibel , Kaymaz Zerefsan
Published: April 2007

A comprehensive examination of 2 yr of radiosonde data to determine the surface duct conditions over Istanbul (4°N, 29°E), Turkey, was made. The refractivity of the atmosphere is a function of air temperature and water vapor pressure. Any negative gradient in the modified refractivity results in the presence of a duct in the atmosphere. Therefore, the occurrence of ducts strongly depends upon both the synoptic and the local meteorological conditions that prevail over the region. The characteristics of surface ducts occurring over Istanbul were examined statistically. It was found that most of the ducts occur in May and July. The highest occurrence rate of surface ducts was observed in the summer season, and the lowest rate was observed in the winter season. The median duct thickness and duct strength are found to be the highest and the strongest in summer, whereas they are the lowest and the weakest in winter. When the data are separated into stable and unstable atmospheric subgroups, it is seen that surface duct characteristics show clear seasonal differences. Surface ducts in a stable atmosphere are found to be stronger than those in an unstable atmosphere. Also, daytime (1200 UTC) surface ducts occur more frequently than nighttime (0000 UTC) surface ducts in Istanbul. These statistics are discussed in association with local meteorological conditions and weather systems affecting the Istanbul region, and comments are made on the importance of their possible consequences in the region.
Low-Frequency Effects on Eddy Covariance Fluxes under the Influence of a Low-Level Jet
Authors: Prabha Thara V. , Leclerc Monique Y. , Karipot Anandakumar , Hollinger David Y.
Published: April 2007

Turbulent bursts observed over a tall forest canopy during the initiation of a nocturnal low-level jet (LLJ) are studied with the help of wavelet analysis. The burst of turbulence is observed in response to a shear instability associated with the initiation of LLJ. Turbulent kinetic energy, momentum, and CO2-rich cold air are transferred downward by large eddies with length scales that are higher than the LLJ height. Microfronts are observed over the canopy as a secondary instability that enhances the mixing processes within and above the canopy. The scale-dependent wavelet correlation analysis reveals that countergradient fluxes result from low frequencies, whereas cogradient flux is associated with high-frequency turbulent motions. The countergradient flux is initially noted at low frequencies, and, through coherent motions, it is transferred to smaller scales with a nearly 20-min delay. The countergradient flux dominates at the initiation of the event and reduces net flux, whereas enhanced cogradient flux at the decay of the event increases the net flux. The wavelet correlation coefficient corresponding to cogradient and countergradient fluxes is applied to segregate three regions of the spectra corresponding to “turbulent,” “coherent,” and “noncoherent” large scales. These findings are used to examine the implications on eddy covariance flux measurements.
Max Weber's Interpretive Economic Sociology
Authors: Swedberg Richard
Published: April 2007

Economic sociology needs more ideas, and in this article the author suggests that economic sociologists may want to explore what a rigorous interpretive economic sociology along Weberian lines would look like. One way to proceed in an enterprise of this type would be to apply the model of analysis that can be found in chapter 1 of Economy and Society to economic sociology and its problems. This means that one has to graft onto economic sociology such key ideas and key concepts in Weber's interpretive sociology as adequate causation, the need to always explore the meaning of actors, and what consequences these meanings have for the resulting action. What a concrete Weberian type of interpretive economic sociology will be like cannot, however, be determined this way. It needs instead to be worked out through concrete, empirical analysis.
Implications for Gifted Education
Authors: Shaunessy Elizabeth
Published: April 2007

This statewide study of teachers of intellectually gifted students examined teachers' attitudes toward information technology. Participants were 418 teachers of the intellectually gifted in a southeastern state who voluntarily responded to a survey about technology attitudes. Results indicated positive attitudes toward technology, with training in information technology as the greatest predictor of attitude. Age of teacher, number of classroom computers, and staff development in information technology also predicted attitudes toward information technology. The relationship of these findings with previous research of attitudes of general education teachers, implications for technology training for teachers of the gifted, and suggestions for future research are discussed.
Love and Work
Authors: Noble Kathleen D. , Vaughan Robert C. , Chan Christina , Childers Sarah , Chow Bryan , Federow Ariel , Hughes Sean
Published: April 2007

This is the second follow-up study of the Early Entrance Program at the University of Washington. Ninety-five individuals (45%) participated. Respondents overwhelmingly chose early university entrance because they were excited to learn; many also praised the peer group, intellectual stimulation, and faculty and staff support. Some reported feeling too young to make important academic, career, and social decisions, with more males regretting the lack of dating partners because of age differences. As the program has matured, so have students' positive experiences in it. Significant differences were found among three groups of students who entered at different points, reflecting this maturation. A wealth of open-ended comments indicated that the program continues to exert a profound and positive influence on graduates' lives.
Cost-Effectiveness of Echocardiography to Identify Intracardiac Thrombus among Patients with First Stroke or Transient Ischemic Attack
Authors: Meenan Richard T. , Saha Somnath , Chou Roger , Swarztrauber Karleen , Pyle Krages Kathryn , O'Keeffe-Rosetti Maureen C. , McDonagh Marian , Chan Benjamin K. S. , Hornbrook Mark C. , Helfand Mark
Published: April 2007

Background and Purpose . Echocardiography to select stroke patients for targeted treatments, such as anticoagulation (AC), to reduce recurrent stroke risk is controversial. The authors' objective was to evaluate the cost-effectiveness of imaging strategies that use transthoracic (TTE) and transesophageal (TEE) echocardiography for identifying intracardiac thrombus in new stroke patients. Methods . Model-based cost-effectiveness analysis of 7 echocardiographic imaging strategies and 2 nontesting strategies with model parameters based on systematic evidence review related to effectiveness of echocardiography in newly diagnosed ischemic stroke patients (white males aged 65 years in base case). Primary outcome was cost per quality-adjusted life year (QALY). Results . All strategies containing TTE were dominated by others and were eliminated from the analysis. Assuming that AC reduces recurrent stroke risk from intracardiac thrombus by 43% over 1 year, TEE generated a cost per QALY of $137,000 (relative to standard treatment) among patients with 5% thrombus prevalence. Cost per QALY dropped to $50,000 in patients with at least 15% intracardiac thrombus prevalence, or, if an 86% relative risk reduction with AC is assumed, in patients with thrombus prevalence of at least 6%. Probabilistic analyses indicate considerable uncertainty around the cost-effectiveness of echocardiography across a wide range of intracardiac thrombus prevalence (pretest probability). Conclusions . Current evidence on cost-effectiveness is insufficient to justify widespread use of echocardiography in stroke patients. Additional research on recurrent stroke risk in patients with intracardiac thrombus and on the efficacy of AC in reducing that risk may contribute to a better understanding of the circumstances under which echocardiography will be cost-effective. Key words: cost-effectiveness; decision analysis; stroke; transesophageal echocardiography; transthoracic echocardiography; diagnostic imaging. (Med Decis Making 2007;27:161—177)
Lumbar Intervertebral Disk Degeneration in Elite Competitive Swimmers
Authors: Kaneoka Koji , Shimizu Ken , Hangai Mika , Okuwaki Toru , Mamizuka Naotaka , Sakane Masataka , Ochiai Naoyuki
Published: April 2007

Background

The majority of orthopaedic problems experienced by competitive swimmers are related to pain in the shoulder, low back, and knee. Three of 39 national swim team members were hampered in their performance due to lumbar disk herniation at an international competition in 2001. There has been no previous research into lumbar disk degeneration in elite competitive swimmers.

Hypothesis

Excessive competitive swimming activities accelerate lumbar disk degeneration.

Study Design

Case control study; Level of evidence, 3.

Methods

Fifty-six elite swimmers (high-load group, 35 men and 21 women; mean age, 19.6 years) and a control group of 38 university recreational level swimmers (low-load group, 24 men and 14 women; mean age, 21.1 years) were evaluated for lumbar disk degeneration using magnetic resonance imaging. We compared the prevalence of disk degeneration and the disk level between the 2 groups and further investigated the relationship among their symptoms, swimming styles, and disk degeneration.

Results

Thirty-eight (68%) elite swimmers and 11 (29%) controls had degenerated disks at various disk levels, and the prevalence was significantly greater in the elite swimmers (P = .0002). Comparison between the 2 groups of the prevalence of disk degeneration at each level revealed that the disk level of L5-S1 was significantly more frequently degenerated in the high-load group (P = .026). There was no significant relationship observed among the variables of low back pain symptoms, swimming strokes, and disk degeneration.

Conclusion

Excessive competitive swimming activities might exaggerate lumbar intervertebral disk degeneration, especially in the L5-S1 intervertebral segment.

Keywords

lumbar intervertebral disk; disk degeneration; swimming; sports
Pragmatic Communicative Action Theory
Authors: Hoch Charles J.
Published: April 2007

Communicative action (CA) theory need not displace the critical insights of social scientists, geographers, and other urban scholars about the processes of social, economic, and political change that shape urban settlements. CA analysts believe we settle differences in research findings and interpretations by studying the consequences these differences produce instead of claiming philosophical trump. In the first part of this article, I summarize and critique the argument that CA theory is unrealistic explaining of how CA analysts care more about relevant consequences than causal certainty. In the second part of the article, taking some conceptual advice from social theorist Jurgen Habermas, I show how CA analysis can combine structural and intentional concepts to revise and integrate the apparent antagonism between comprehensiveness and compromise for planning practice. I conclude that a pragmatic CA provides a useful and critical theory for planning practice that remains open to future challenge and debate.
Death on the Crosswalk
Authors: Loukaitou-Sideris Anastasia , Liggett Robin , Sung Hyun-Gun
Published: April 2007

This research explores the spatial distribution of pedestrian-automobile collisions in Los Angeles and analyzes the social and physical factors that affect the risk of getting involved in such collisions. More specifically, this study investigates the influence of socio-demographic, land use, density, urban form, and traffic characteristics on pedestrian collision rates. We first provide an exploratory spatial and statistical analysis of pedestrian collision data in the city of Los Angeles to identify preliminary relationships between the frequency of collisions and socio-demographic and land use characteristics at the census tract level. This aggregate level analysis points to major concentrations of pedestrian collision data which are used at a second stage of the research for more qualitative and detailed analysis of specific case studies of intersections with high frequency of pedestrian collisions.
Nutritional Vitamin D Deficiency Presenting as Hemichorea
Authors: Fernandez Romeo , Ashraf Ambika , Dure Leon S.
Published: April 2007

The authors describe a pediatric patient with repaired hypoplastic left heart syndrome developing protein-losing enteropathy, hypocalcemia, vitamin D deficiency, and hemichorea. After correction of nutritional vitamin D deficiency with calcium and vitamin D supplementation, the chorea resolved. Hypoalbuminemia also improved after the correction of vitamin D deficiency without requiring albumin infusions. This report also raises the possible role of calcium or vitamin D in the intestinal loss of albumin in protein-losing enteropathy.
Cerebral Hemorrhage as the Initial Manifestation of Cystic Fibrosis
Authors: Hamid Basem , Khan Atiya
Published: April 2007

The authors present a case of an infant boy, otherwise healthy, who presented with acute irritability and obtundation. A head computed tomography scan revealed massive intracerebral hemorrhage. Investigations of the etiology revealed abnormal clotting times and reduced activity of all vitamin K—dependent factors. All etiologies of vitamin K deficiency were ruled out except malabsorption. The diagnosis of cystic fibrosis was confirmed by sweat chloride and genetic testing. Cystic fibrosis could present with cerebral bleed and should be considered in its differential diagnosis when other etiologies are not clear, as the other manifestations of vitamin K deficiency could be very subtle and unnoticed. Screening and early diagnosis of cystic fibrosis may prevent serious complications.
Brain Malformation of the Surviving Twin of Intrauterine Co-twin Demise
Authors: Okumura Akihisa , Hayakawa Fumio , Kato Toru , Tsuji Takeshi , Negoro Tamiko , Watanabe Kazuyoshi
Published: April 2007

The authors report the case of a surviving twin patient with severe brain malformation due to intrauterine fetal demise of the other twin. The patient was a boy with 37 weeks of gestational age. Intrauterine death of the co-twin was discovered at 18 weeks of gestation. No major anomalies were recognized at birth except for microcephalus. Magnetic resonance imaging demonstrated wide sylvian fissures, bilateral ventriculomegaly, and smooth brain surface of the temporoparieto-occipital lobes. He had spastic quadriplegia and severe mental retardation. Brief tonic seizures appeared at 7 months of age. Clonazepam was administered, and seizures disappeared at 24 months of age. Complex partial seizures began at 8 years of age. Seizures were observed weekly despite treatment with carbamazepine. The malformation of our patient was considered to be a result of a mixture of destructive process and disorders of neuronal proliferation and migration.
Cost-effectiveness of Intrathecal Baclofen Therapy for the Treatment of Severe Spasticity Associated With Cerebral Palsy
Authors: de Lissovoy Gregory , Matza Louis S. , Green Hannah , Werner Meghan , Edgar Terence
Published: April 2007

Spasticity is relatively common among children with cerebral palsy. This condition can be painful, can severely impair a child's ability to perform basic tasks, and can place an enormous emotional and financial burden on the family. Intrathecal baclofen delivered via an implantable pump is an effective treatment option for children unresponsive to oral medication and needing generalized motor control. However, the initial investment for the delivery device and its surgical placement can be a barrier to access. A cost-effectiveness analysis of intrathecal baclofen for adults in the British health care system concluded that intrathecal baclofen offered good value for the money. No similar analysis of intrathecal baclofen has been conducted in the context of the US health care system, and no study has specifically examined cost-effectiveness of intrathecal baclofen in a pediatric population. The aim of this article is to assess the cost-effectiveness of intrathecal baclofen among children with severe spasticity of cerebral origin who have not responded to less invasive treatments such as oral medications relative to alternative medical and surgical therapy. The authors used mathematical modeling and computer simulation to estimate the incremental cost per quality-adjusted life-year for identical cohorts of children treated with intrathecal baclofen or alternative therapy over a 5-year episode of treatment. Data on treatment costs representative of these children were derived from a health insurance claims database that included both commercial and Medicaid data. Utility values used to construct quality-adjusted life-years were obtained from a panel of expert clinicians who used the Health Utilities Index—2 to rate health states associated with the course of treatment. On average, intrathecal baclofen therapy increased the 5-year cost of treatment by $49 000 relative to alternative treatment. However, this was accompanied by an average gain of 1.2 quality-adjusted life-years. The net result was an incremental cost-effectiveness ratio of $42 000 per quality-adjusted life-year, a figure well within the $50 000 to $100 000 range that is widely accepted as offering good value for the money.
Physical Activity and the Risk of Dementia in Oldest Old
Authors: Sumic Aleksandra , Michael Yvonne L. , Carlson Nichole E. , Howieson Diane B. , Kaye Jeffrey A.
Published: April 2007

Objective: This study evaluated the protective role of physical activity (PA) against cognitive impairment (CI) in the oldest old (age ≥ 85). Method: Prospective data on 66 optimally healthy, oldest old adults (mean age 88.5) were analyzed using survival analysis. Results: In all, 12 men and 11 women reported exercising > 4 hours per week, and 38 participants developed CI (mean onset age 93; mean follow-up 4.7 years). The effect of exercise was modified by gender. In more active women (> 4 hours/week), the risk of CI was reduced by 88% (95% confidence interval 0.03, 0.41) compared to those less active. Less active women had 2 times the incidence rate of CI compared to less active men and almost 5 times the rate compared to active women. Discussion: This study demonstrates the beneficial effects of exercise on healthy brain aging even in the oldest old and emphasizes the importance of increasing PA in older women.
The Tensions Between Academic Freedom and Institutional Review Boards
Authors: Tierney William G. , Blumberg Corwin Zoë
Published: April 2007

Academic freedom and the protection of human research subjects are central tenets of American universities. Academic freedom protects the rights of tenured professors to conduct autonomous research; human subject protection ensures that research causes as minimal a risk as possible to study participants. Although the two principles are mutually exclusive, recent trends in Institutional Review Board jurisdiction have placed the two principles in increasing conflict with one another. This article outlines three ways in which Institutional Review Boards potentially infringe on academic freedom: (a) by regulating who is required to consent to research, (b) by stipulating the type of questions allowed and location of research interactions, and (c) by limiting research design.