bluuebunny/crossref_metadata_2025 huggingface dataset:
Effects of waste glass additions on the properties and durability of fired clay brickThis article is one of a selection of papers published in this Special Issue on Masonry.
Authors: Chidiac S. E. , Federico L. M.
Published: April 2008

The optimization of the production of fired clay brick is essential for the sustainability of the clay brick industry. While there exist areas for improvement of these bricks’ properties when they are used in severe climates, concerns — including nonrenewable resource depletion, increasing energy costs, and waste management — have become increasingly important in Canadian and global industries. One strategy to address these concerns is to use waste additives as fluxing agents in bricks. Use of these additives can decrease the dependency of the industry on nonrenewable resources and can improve brick strength and durability. The effect nonrecycled waste glass additives have on fired brick durability and mechanical and transport properties was investigated in this study. The variables studied were waste glass particle size and percentage added by mass. Microstructure was investigated using mercury intrusion porosimetry to determine the effect on pore structure. The results yielded an optimal percentage addition of waste glass.
Damage as a measure for earthquake-resistant design of masonry structures: Slovenian experienceThis article is one of a selection of papers published in this Special Issue on Masonry.
Authors: Tomaževič Miha
Published: April 2008

The results of lateral resistance tests of masonry walls and shaking table tests of a number of models of masonry buildings of various structural configurations, built with various materials in different construction systems, have been analyzed to find a correlation between the occurrence of different grades of damage to structural elements, characteristic limit states, and lateral displacement capacity. On the basis of correlation between acceptable level of damage and displacement capacity, it has been shown that the range of elastic force reduction factor values used to determine the design seismic loads for different masonry construction systems proposed by the recently adopted European standard Eurocode 8 EN-1998-1 for earthquake resistant design are adequate. By using the recommended design values, satisfactory performance of the masonry buildings that have been analyzed may be expected when subjected to design intensity earthquakes with respect to both the no-collapse and damage-limitation requirements.
THE CLIQUE-WIDTH OF BIPARTITE GRAPHS IN MONOGENIC CLASSES
Authors: LOZIN VADIM V. , VOLZ JORDAN
Published: April 2008

In this paper, we provide complete classification of classes of bipartite graphs defined by a single forbidden induced bipartite subgraph with respect to bounded/unbounded clique-width.
UNCERTAINTY IN THE ECONOMICS OF MEDICAL DECISIONS
Authors: LANE JOHN , TSANG SANDRO
Published: April 2008

A physician chooses not only the supply of medical treatment, contingent on the result of a diagnostic test, but also the quality of his service. Two sources of uncertainty are introduced. One source arises as, based on the patient's "apparent" symptoms, only a priori estimates of the likelihood of alternative medical conditions can be inferred. They can be improved upon by a diagnostic test, but inherent in such tests is the possibility of a "false positive". This second source of uncertainty is shown to be critical in the possible over- or undersupply of medical treatment. Remedial pricing structures are suggested.
HEALTH CARD AND HEALTH CARE FACILITIES DEMAND AMONG THE INDONESIAN ELDERLY
Authors: MALIKI
Published: April 2008

This paper evaluates the benefits of the health card subsidy, issued by the Indonesian government after the financial crisis in 1997, on elderly health care demand. The health card subsidy provides free access to health services, and was accepted at any available health center or puskesmas. Using the Indonesia Socioeconomic survey data (Susenas) for 2003, results show that health cards issued to the poor consistently increase the demand for health care facilities among the old population. Unfortunately, it is also found that the health card benefited wealthier individuals in their access to health centers or puskesmas.
UNCERTAINTY MEASURE OF ROUGH SETS BASED ON A KNOWLEDGE GRANULATION FOR INCOMPLETE INFORMATION SYSTEMS
Authors: WANG JUNHONG , LIANG JIYE , QIAN YUHUA , DANG CHUANGYIN
Published: April 2008

Rough set theory is a relatively new mathematical tool for computer applications in circumstances characterized by vagueness and uncertainty. In this paper, we address uncertainty of rough sets for incomplete information systems. An axiom definition of knowledge granulation for incomplete information systems is obtained, under which a measure of uncertainty of a rough set is proposed. This measure has some nice properties such as equivalence, maximum and minimum. Furthermore, we prove that the uncertainty measure is effective and suitable for measuring roughness and accuracy of rough sets for incomplete information systems.
Adaptive probability-based broadcast forwarding in energy-saving sensor networks
Authors: Sengul Cigdem , Miller Matthew J. , Gupta Indranil
Published: April 2008

Networking protocols for multihop wireless sensor networks (WSNs) are required to simultaneously minimize resource usage as well as optimize performance metrics such as latency and reliability. This article explores the energy-latency-reliability tradeoff for broadcast in WSNs by presenting a new protocol called
PBBF
. Essentially, for a given reliability level, energy and latency are found to be inversely related and our study quantifies this relationship at the reliability boundary. Therefore, PBBF offers an application designer considerable flexibility in the choice of desired operation points. Furthermore, we propose an extension to dynamically adjust the PBBF parameters to minimize the input required from the designer.
Discovering semantic biomedical relations utilizing the Web
Authors: Sahay Saurav , Mukherjea Sougata , Agichtein Eugene , Garcia Ernest V. , Navathe Shamkant B. , Ram Ashwin
Published: April 2008

To realize the vision of a Semantic Web for Life Sciences, discovering relations between resources is essential. It is very difficult to automatically extract relations from Web pages expressed in natural language formats. On the other hand, because of the explosive growth of information, it is difficult to manually extract the relations. In this paper we present techniques to automatically discover relations between biomedical resources from the Web. For this purpose we retrieve relevant information from Web Search engines and Pubmed database using various lexico-syntactic patterns as queries over SOAP web services. The patterns are initially handcrafted but can be progressively learnt. The extracted relations can be used to construct and augment ontologies and knowledge bases. Experiments are presented for general biomedical relation discovery and domain specific search to show the usefulness of our technique.
Adaptive discriminant analysis for microarray-based classification
Authors: Lu Yijuan , Tian Qi , Neary Jennifer , Liu Feng , Wang Yufeng
Published: April 2008

Microarray technology has generated enormous amounts of high-dimensional gene expression data, providing a unique platform for exploring gene regulatory networks. However, the curse of dimensionality plagues effort to analyze these high throughput data. Linear Discriminant Analysis (LDA) and Biased Discriminant Analysis (BDA) are two popular techniques for dimension reduction, which pay attention to different roles of the positive and negative samples in finding discriminating subspace. However, the drawbacks of these two methods are obvious: LDA has limited efficiency in classifying sample data from subclasses with different distributions, and BDA does not account for the underlying distribution of negative samples.

In this paper, we propose a novel dimension reduction technique for microarray analysis: Adaptive Discriminant Analysis (ADA), which effectively exploits favorable attributes of both BDA and LDA and avoids their unfavorable ones. ADA can find a good discriminative subspace with adaptation to different sample distributions. It not only alleviates the problem of high dimensionality, but also enhances the classification performance in the subspace with naïve Bayes classifier. To learn the best model fitting the real scenario, boosted Adaptive Discriminant Analysis is further proposed. Extensive experiments on the yeast cell cycle regulation data set, and the expression data of the red blood cell cycle in malaria parasite
Plasmodium falciparum
demonstrate the superior performance of ADA and boosted ADA. We also present some putative genes of specific functional classes predicted by boosted ADA. Their potential functionality is confirmed by independent predictions based on Gene Ontology, demonstrating that ADA and boosted ADA are effective dimension reduction methods for microarray-based classification.
Coordination in answer set programming
Authors: Sakama Chiaki , Inoue Katsumi
Published: April 2008

This article studies a semantics of multiple logic programs, and synthesizes a program having such a collective semantics. More precisely, the following two problems are considered: given two logic programs
P
1
and
P
2
, which have the collections of answer sets
AS
(
P
1
) and
AS
(
P
2
), respectively; (i) find a program
Q
which has the set of answer sets such that
AS
(
Q
) =
AS
(
P
1
) ∪
AS
(
P
2
); (ii) find a program
R
which has the set of answer sets such that
AS
(
R
) =
AS
(
P
1
) ∩
AS
(
P
2
). A program
Q
satisfying the condition (i) is called
generous coordination
of
P
1
and
P
2
; and
R
satisfying (ii) is called
rigorous coordination
of
P
1
and
P
2
. Generous coordination retains all of the answer sets of each program, but permits the introduction of additional answer sets of the other program. By contrast, rigorous coordination forces each program to give up some answer sets, but the result remains within the original answer sets for each program. Coordination provides a program that reflects the meaning of two or more programs. We provide methods for constructing these two types of coordination and address its application to logic-based multi-agent systems.
Alternating timed automata
Authors: Lasota Slawomir , Walukiewicz Igor
Published: April 2008

A notion of alternating timed automata is proposed. It is shown that such automata with only one clock have decidable emptiness problem over finite words. This gives a new class of timed languages that is closed under boolean operations and which has an effective presentation. We prove that the complexity of the emptiness problem for alternating timed automata with one clock is nonprimitive recursive. The proof gives also the same lower bound for the universality problem for nondeterministic timed automata with one clock. We investigate extension of the model with epsilon-transitions and prove that emptiness is undecidable. Over infinite words, we show undecidability of the universality problem.
Writeprints
Authors: Abbasi Ahmed , Chen Hsinchun
Published: April 2008

One of the problems often associated with online anonymity is that it hinders social accountability, as substantiated by the high levels of cybercrime. Although identity cues are scarce in cyberspace, individuals often leave behind textual identity traces. In this study we proposed the use of stylometric analysis techniques to help identify individuals based on writing style. We incorporated a rich set of stylistic features, including lexical, syntactic, structural, content-specific, and idiosyncratic attributes. We also developed the Writeprints technique for identification and similarity detection of anonymous identities. Writeprints is a Karhunen-Loeve transforms-based technique that uses a sliding window and pattern disruption algorithm with individual author-level feature sets. The Writeprints technique and extended feature set were evaluated on a testbed encompassing four online datasets spanning different domains: email, instant messaging, feedback comments, and program code. Writeprints outperformed benchmark techniques, including SVM, Ensemble SVM, PCA, and standard Karhunen-Loeve transforms, on the identification and similarity detection tasks with accuracy as high as 94% when differentiating between 100 authors. The extended feature set also significantly outperformed a baseline set of features commonly used in previous research. Furthermore, individual-author-level feature sets generally outperformed use of a single group of attributes.
Enforcing appropriate process execution for exploiting idle resources from outside operating systems
Authors: Abe Yoshihisa , Yamada Hiroshi , Kono Kenji
Published: April 2008

Idle resources can be exploited not only to run important local tasks such as data replication and virus checking, but also to make contributions to society by participating in open computing projects like SETI@home [2]. When executing background processes to utilize such valuable idle resources, we need to explicitly control them so that the user will not be discouraged from exploiting idle resources by foreground performance degradation. Unfortunately, common priority-based schedulers lack such explicit execution control. In addition, to encourage active use of idle resources, a mechanism for controlling background processes should not require modifications to the underlying operating system or user applications. If such modifications are required, the user may be reluctant to employ the mechanism.

In this paper, we argue that we can reasonably detect resource contention between foreground and background processes and properly control background process execution at the user level. We infer the existence of resource contention from the approximated resource shares of background processes. Our approach takes advantage of dynamically instrumented probes, which are becoming increasingly popular, in estimating the resource shares. Also, it considers different resource types in combination and can handle varied workloads, including multiple background processes.

We show that our system effectively avoids the performance degradation of foreground activities by suspending background processes in an appropriate fashion. Our system keeps the increase in foreground execution time due to background processes below 16.9%, or much lower in most of our experiments. Also, we extend our approach to address undesirable resource allocations to CPU-intensive processes that can occur in multiprocessor environments.
Application-level isolation and recovery with solitude
Authors: Jain Shvetank , Shafique Fareha , Djeric Vladan , Goel Ashvin
Published: April 2008

When computer systems are compromised by an attack, it is difficult to determine the precise extent of the damage caused by the attack because the state changes made by an attacker and those made by regular users can be closely intertwined. This problem occurs due to implicit sharing in operating systems, and it can be especially severe for persistent state. In particular, the file system provides a single namespace that when compromised can have cascading effects on the entire system, making intrusion analysis and recovery a time-consuming and error-prone process.

In this paper, we present Solitude, an application-level isolation and recovery system that is designed to both limit the effects of attacks and simplify the post-intrusion recovery process. Solitude uses a copy-on-write filesystem to provide a transparent, restricted privilege isolation environment for running untrusted applications, and it uses an explicit file sharing mechanism across the isolation environments that limits attack propagation without compromising functionality. Solitude provides two modes of recovery. If a sandboxed application proves to be untrustworthy, a course-grained recovery method allows easily removing the footprint of the software. However, if a user mistakenly moves malicious files to the trusted environment via explicit file sharing, then Solitude uses data dependency tracking to allow fine-grained recovery.
Itrustpage
Authors: Ronda Troy , Saroiu Stefan , Wolman Alec
Published: April 2008

Despite the many solutions proposed by industry and the research community to address phishing attacks, this problem continues to cause enormous damage. Because of our inability to deter phishing attacks, the research community needs to develop new approaches to anti-phishing solutions. Most of today's anti-phishing technologies focus on automatically detecting and preventing phishing attacks. While automation makes anti-phishing tools user-friendly, automation also makes them suffer from false positives, false negatives, and various practical hurdles. As a result, attackers often find simple ways to escape automatic detection.

This paper presents iTrustPage - an anti-phishing tool that does not rely completely on automation to detect phishing. Instead, iTrustPage relies on user input and external repositories of information to prevent users from filling out phishing Web forms. With iTrustPage, users help to decide whether or not a Web page is legitimate. Because iTrustPage is user-assisted, iTrustPage avoids the false positives and the false negatives associated with automatic phishing detection. We implemented iTrustPage as a downloadable extension to FireFox. After being featured on the Mozilla website for FireFox extensions, iTrustPage was downloaded by more than 5,000 users in a two week period. We present an analysis of our tool's effectiveness and ease of use based on our examination of usage logs collected from the 2,050 users who used iTrustPage for more than two weeks. Based on these logs, we find that iTrustPage disrupts users on fewer than 2% of the pages they visit, and the number of disruptions decreases over time.
SNAP package for Mathematica
Authors: Nagasaka Kosaku
Published: April 2008

SNAP (Symbolic Numeric Algebra for Polynomials) package for
Mathematica
provides various functions to compute approximate algebraic properties including approximate GCD and factorization of polynomials for example. For practical situations, the package does not have enough functionalities yet. However, the aim of this package is showing how an unified tolerance mechanism that we introduced for the package works. With that, we can continue approximate calculations under certified tolerances without special skills in symbolic-numeric algebra.
Implementation of CGS and CGB on Risa/Asir and other computer algebra systems using Suzuki-Sato algorithm
Authors: Suzuki Akira , Sato Yosuke
Published: April 2008

In [5], we showed simple algorithms to compute comprehensive Gröbner systems (CGS) and comprehensive Gröbner bases (CGB). We call them Suzuki-Sato algorithms in this paper. Other known existing software packages to compute CGS or CGB are CGB of Redlog (Weispfenning) [1], DISPGB, and MCCGS (Montes) [2, 3].
GAP
Authors: Linton Steve
Published: April 2008

GAP is a system for computational discrete algebra, with particular emphasis on Computational Group Theory. GAP provides a programming language, a library of thousands of functions implementing algebraic algorithms written in the GAP language, large data libraries of algebraic objects and a growing collection of user-contributed extension packages. GAP is widely used in research and teaching for studying groups and their representations, rings, vector spaces, algebras, combinatorial structures, codes, Lie algebras and more. It has been cited in over 800 published papers. The system, including source, is distributed freely. You can study and easily modify or extend it for your special use.
ALLTYPES in the web
Authors: Schwarz Fritz
Published: April 2008

ALLTYPES which abbreviates
ALgebraic Language and TYPe System
provides an interactive environment in the internet that is particularly well suited for performing symbolic computations in differential algebra. Its novel design has been guided by the following principles.
SyNRAC
Authors: Yanami Hitoshi , Anai Hirokazu
Published: April 2008

We introduce various aspects of design and implementation of a symbolic computation toolbox, called SyNRAC, handling first-order formulas on top of Maple. SyNRAC provides us with a new set of tools for solving real algebraic constraints derived from a broad range of applications in science and engineering.
AXIOM
Authors: Page William S.
Published: April 2008

Axiom has been in development since 1971. Originally called Scratchpad II, it was developed by IBM under the direction of Richard Jenks[1]. The project evolved over a period of 20 years as a research platform for developing new ideas in computational mathematics. ScratchPad also attracked the interest and contributions of a large number of mathematicians and computer scientists outside of IBM. In the 1990s, the Scratchpad project was renamed to Axiom, and sold to the Numerical Algorithms Group (NAG) in England who marketed it as a commercial system. NAG withdrew Axiom from the market in October 2001 and agreed to release Axiom as free software, under an open source license.

Tim Daly (a former ScratchPad developer at IBM) setup a pubic open source Axiom project[2] in October 2002 with a primary goal to improve the documentation of Axiom through the extensive use of literate programming[3]. The first free open source version of Axiom was released in 2003. Since that time the project has attracted a small but very active group of developers and a growing number of users.

This exhibit includes a laptop computer running a recent version of Axiom, Internet access (if available) to the Axiom Wiki website[4], and CDs containing Axiom software for free distribution[5].
Needed
Authors: Attiya Hagit
Published: April 2008

Transactional memory
is a leading paradigm for designing concurrent applications for tomorrow's multi-core architectures. It follows and draws much inspiration from earlier research on concurrent data structures and concurrency control. Quite remarkably, it has succeeded in breaking out of the research community, and is being seriously considered by the industry---both as part of software solutions and as the basis for novel hardware designs.
Distributed computing and the multicore revolution
Authors: Herlihy Maurice , Luchangco Victor
Published: April 2008

Changes in technology can have far-reaching effects on theory. For example, while Turing's work on computability predated the first electronic computers, complexity theory flowered only after computers became a reality. After all, an algorithm's complexity may not matter much in a mathematics journal, but matters quite a bit in a FORTRAN program. We argue that something similar is going on with parallel and concurrent computation: after decades of being respected but not taken seriously, research on multiprocessor algorithms and data structures is going mainstream.
VariaSim
Authors: Romanescu Bogdan F. , Bauer Michael E. , Ozev Sule , Sorin Daniel J.
Published: April 2008

In this paper, we present VariaSim, the publicly available Static Statistical Timing Analysis (SSTA) Tool from Duke University. VariaSim enables researchers to analyze the impact of CMOS process variability on the behavior of circuits and systems.
Repetitive deformation activates Src-independent FAK-dependent ERK motogenic signals in human Caco-2 intestinal epithelial cells
Authors: Chaturvedi Lakshmi S. , Gayer Christopher P. , Marsh Harold M. , Basson Marc D.
Published: April 2008

Repetitive deformation due to villous motility or peristalsis may support the intestinal mucosa, stimulating intestinal epithelial proliferation under normal circumstances and restitution in injured and inflamed mucosa rich in tissue fibronectin. Cyclic strain enhances Caco-2 and IEC-6 intestinal epithelial cell migration across fibronectin via ERK. However, the upstream mediators of ERK activation are unknown. We investigated whether Src and FAK mediate strain-induced ERK phosphorylation and migration in human Caco-2 intestinal epithelial cells on fibronectin. Monolayers on tissue fibronectin-precoated membranes were subjected to an average 10% repetitive deformation at 10 cycles/min. Phosphorylation of Src-Tyr418, FAK-Tyr397-Tyr576-Tyr925, and ERK were significantly increased by deformation. The stimulation of wound closure by strain was prevented by Src blockade with PP2 (10 μmol/l) or specific short interfering (si)RNA. Src inhibition also prevented strain-induced FAK phosphorylation at Tyr397 and Tyr576 but not FAK-Tyr925 or ERK phosphorylation. Reducing FAK by siRNA inhibited strain-induced ERK phosphorylation. Transfection of NH2-terminal tyrosine phosphorylation-deficient FAK mutants Y397F, Y576F-Y577F, and Y397F-Y576F-Y577F did not prevent the activation of ERK2 by cyclic strain, but a FAK mutant at the COOH terminal (Y925F) prevented the strain-induced activation of ERK2. Although the Y397F-Y576F-Y577F FAK construct exhibited less basal FAK-Tyr925 phosphorylation under static conditions, it nevertheless exhibited increased FAK-Tyr925 phosphorylation in response to strain. These results suggest that repetitive deformation stimulates intestinal epithelial motility across fibronectin in a manner that requires both Src activation and a novel Src-independent FAK-Tyr925-dependent pathway that activates ERK. This pathway may be an important target for interventions to promote mucosal healing in settings of intestinal ileus or fasting.
Insulin-like growth factor I and II regulate the life cycle of trophoblast in the developing human placenta
Authors: Forbes Karen , Westwood Melissa , Baker Philip N. , Aplin John D.
Published: April 2008

The main disorders of human pregnancy are rooted in defective placentation. Normal placental development depends on proliferation, differentiation, and fusion of cytotrophoblasts to form and maintain an overlying syncytiotrophoblast. There is indirect evidence that the insulin-like growth factors (IGFs), which are aberrant in pregnancy disorders, are involved in regulating trophoblast turnover, but the processes that control human placental growth are poorly understood. Using an explant model of human first-trimester placental villus in which the spatial and ontological relationships between cell populations are maintained, we demonstrate that cytotrophoblast proliferation is enhanced by IGF-I/IGF-II and that both factors can rescue cytotrophoblast from apoptosis. Baseline cytotrophoblast proliferation ceases in the absence of syncytiotrophoblast, although denuded cytotrophoblasts can proliferate when exposed to IGF and the rate of cytotrophoblast differentiation/fusion and, consequently, syncytial regeneration, increases. Use of signaling inhibitors suggests that IGFs mediate their effect on cytotrophoblast proliferation/syncytial formation through the MAPK pathway, whereas effects on survival are regulated by the phosphoinositide 3-kinase pathway. These results show that directional contact between cytotrophoblast and syncytium is important in regulating the relative amounts of the two cell populations. However, IGFs can exert an exogenous regulatory influence on placental growth/development, suggesting that manipulation of the placental IGF axis may offer a potential therapeutic route to the correction of inadequate placental growth.
A highly sensitive technique to measure myosin regulatory light chain phosphorylation: the first quantification in renal arterioles
Authors: Takeya Kosuke , Loutzenhiser Kathy , Shiraishi Mitsuya , Loutzenhiser Rodger , Walsh Michael P.
Published: April 2008

Phosphorylation of the 20-kDa myosin regulatory light chains (LC20) plays a key role in the regulation of smooth muscle contraction. The level of LC20phosphorylation is governed by the relative activities of myosin light chain kinase and phosphatase pathways. The regulation of these two pathways differs in different smooth muscle types and in the actions of different vasoactive stimuli. Little is known concerning the regulation of LC20phosphorylation in the renal microcirculation. The available pharmacological probes are often nonspecific, and current techniques to directly measure LC20phosphorylation are not sensitive enough for quantification in small arterioles. We describe here a novel approach to address this important issue. Using SDS-PAGE with polyacrylamide-bound Mn2+-phosphate-binding tag and enhanced Western blot analysis, we were able to detect LC20phosphorylation using as little as 5 pg (250 amol) of isolated LC20. Phosphorylated and unphosphorylated LC20were detected in single isolated afferent arterioles, and LC20phosphorylation levels could be accurately quantified in pooled samples of three arterioles (<300 cells). The phosphorylation level of LC20in the afferent arteriole was 6.8 ± 1.7% under basal conditions and increased to 34.7 ± 5.1% and 44.6 ± 6.6% in response to 30 mM KCl and 10−8M angiotensin II, respectively. The application of this technique will enable investigations of the different determinants of LC20phosphorylation in afferent and efferent arterioles and provide insights into the signaling pathways that regulate LC20phosphorylation in the renal microvasculature under physiological and pathophysiological conditions.
The Solute Carrier 26 Family of Proteins in Epithelial Ion Transport
Authors: Dorwart Michael R. , Shcheynikov Nikolay , Yang Dongki , Muallem Shmuel
Published: April 2008

Transepithelial Cl−and HCO3−transport is critically important for the function of all epithelia and, when altered or ablated, leads to a number of diseases, including cystic fibrosis, congenital chloride diarrhea, deafness, and hypotension ( 78 , 111 , 119 , 126 ). HCO3−is the biological buffer that maintains acid-base balance, thereby preventing metabolic and respiratory acidosis ( 48 ). HCO3−also buffers the pH of the mucosal layers that line all epithelia, protecting them from injury ( 2 ). Being a chaotropic ion, HCO3−is essential for solubilization of ions and macromolecules such as mucins and digestive enzymes in secreted fluids. Most epithelia have a Cl−/HCO3exchange activity in the luminal membrane. The molecular nature of this activity remained a mystery for many years until the discovery of SLC26A3 and the realization that it is a member of a new family of Cl−and HCO3−transporters, the SLC26 family ( 73 , 78 ). This review will highlight structural features, the functional diversity, and several regulatory aspects of the SLC26 transporters.
Mitochondria: The Hub of Cellular Ca2+Signaling
Authors: Szabadkai György , Duchen Michael R.
Published: April 2008

Mitochondria couple cellular metabolic state with Ca2+transport processes. They therefore control not only their own intra-organelle [Ca2+], but they also influence the entire cellular network of cellular Ca2+signaling, including the endoplasmic reticulum, the plasma membrane, and the nucleus. Through the detailed study of mitochondrial roles in Ca2+signaling, a remarkable picture of inter-organelle communication has emerged. We here review the ways in which this system provides integrity and flexibility for the cell to cope with the countless demands throughout its life cycle and discuss briefly the mechanisms through which it can also drive cell death.
Arsenic-Based Antineoplastic Drugs and Their Mechanisms of Action
Authors: Ralph Stephen John
Published: April 2008

Arsenic-based compounds have become accepted agents for cancer therapy providing high rates of remission of some
cancers such as acute promyelocytic leukemia (APL). The mechanisms by which arsenic-containing compounds kill cells and
reasons for selective killing of only certain types of cancer cells such as APLs have recently been delineated. This knowledge
was gained in parallel with increasing understanding and awareness of the importance of intracellular redox systems and
regulation of the production of reactive oxygen species (ROS) by controlling mitochondrial function. Many of the targets for
the arsenic-containing compounds are mitochondrial proteins involved in regulating the production of ROS. Inhibition of these
proteins by disulfide linkage of vicinal thiol groups often leads to increased production of ROS and induction of apoptotic
signalling pathways. Sensitivity or resistance to the actions of arsenic-containing compounds on cancer cells and normal
cells depends on the levels of transport systems for their uptake or efflux from the cells as well as their redox defence
mechanisms. The exact mechanisms of arsenic toxicity as well as its anticancer properties are likely to be related and these
aspects of arsenic metabolism are covered in this review. Greater understanding of the mechanisms of action of arsenic will
help determine the risks of human exposure to this chemical. Novel organic arsenic-containing compounds and the lessons
learned from studying their selective sensitivity in targeting dividing endothelial cells to inhibit angiogenesis raise the future
possibility for designing better targeted antineoplastic arsenic-containing compounds with less toxicity to normal cells.
3D Wavelet Subbands Mixing for Image Denoising
Authors: Coupé Pierrick , Hellier Pierre , Prima Sylvain , Kervrann Charles , Barillot Christian
Published: April 2008

A critical issue in image restoration is the problem of noise removal
while keeping the integrity of relevant image information. The method
proposed in this paper is a fully automatic 3D blockwise version of the
nonlocal (NL) means filter with wavelet subbands mixing. The proposed
wavelet subbands mixing is based on a multiresolution approach
for improving the quality of image denoising filter. Quantitative validation
was carried out on synthetic datasets generated with the BrainWeb simulator.
The results show that our NL‐means filter with wavelet subbands
mixing outperforms the classical implementation of the NL‐means filter in
terms of denoising quality and computation time. Comparison with wellestablished
methods, such as nonlinear diffusion filter and total variation
minimization, shows that the proposed NL‐means filter produces better
denoising results. Finally, qualitative results on real data are presented.
Design Aspects of Printed Monopole Antennas for Ultra‐Wide Band Applications
Authors: Ray K. P.
Published: April 2008

This paper presents the design equations for lower band‐edge frequency for all the regular shapes of printed monopole antennas with various feed positions. The length of the feed transmission line is a critical design parameter of these monopole antennas. Design curves for the length of the feed transmission line for various lower band‐edge frequencies for all these regular shaped monopoles have been generated. A systematic study has been presented to explain the ultra‐wide bandwidth obtained from these antennas with an example of elliptical monopole antenna.
Intended Coping Responses to Cancer Symptoms in Healthy Adults: The Roles of Symptom Knowledge, Detection Behavior, and Perceived Threat
Authors: Ruiter Robert A.C. , de Nooijer Jascha , van Breukelen Gerard , Ockhuysen-Vermey Caroline F. , de Vries Hein
Published: April 2008

Background: To date, the causal effects of the knowledge of cancer-related symptoms and detection behavior on coping with cancer-related symptoms have not been identified. Therefore, the current study explored the effects of active or passive detection of supposedly well-known or less-known cancer-related symptoms on intended coping responses. In addition, we were interested in the extent to which these effects are driven by heightened perceptions of threat.

Methods: In an experimental study using a 2 × 2 within-subject design, 221 Dutch adults from the general population responded to a survey study sent to their homes (18.4% response). They were asked to read scenario information about four cancer-related symptoms that were (a) well known or less known and (b) actively or passively detected (e.g., self-examination versus unusual blood loss). The authors measured intended coping responses to the detection of cancer-related symptoms as either adaptive (e.g., visiting a general practitioner) or maladaptive (e.g., denial of the symptom).

Results: As expected, the findings revealed that well-known symptoms resulted in more anticipated adaptive coping and less anticipated maladaptive coping than less-known symptoms. Unfortunately, the findings also suggest that the active as opposed to passive detection of cancer symptoms (e.g., self-examination versus unusual blood loss) is likely to result in more maladaptive coping. These effects were mediated by heightened perceptions of threat.

Conclusions: Future health education programs that aim to motivate people to be more active in the early detection of cancer symptoms should first focus on increasing people's knowledge about the early warning signs of cancer. (Cancer Epidemiol Biomarkers Prev 2008;17(4):818–26)
Family History of Cancer and Associated Risk of Developing Neuroendocrine Tumors: A Case-Control Study
Authors: Hassan Manal M. , Phan Alexandria , Li Donghui , Dagohoy Cecile G. , Leary Colleen , Yao James C.
Published: April 2008

Background: Carcinoids are rare neuroendocrine tumors (NET). Familial clusterings of NETs are rarely reported, except for a small proportion associated with multiple endocrine neoplasia syndrome type 1. We evaluated the effect of positive family history of NET as well as other cancers on the development of NETs arising at five different locations.

Methods: We conducted a retrospective, hospital-based, case-control study involving 740 patients with histologically confirmed NETs and 924 healthy controls. Information on family history of cancer was collected, and unconditional logistic regression analysis was used to determine adjusted odds ratios (AOR) and 95% confidence intervals (CI).

Results: The authors observed a significant relationship between first-degree relatives with cancers and the development of NETs arising at the small intestine, stomach, lung, and pancreas; AORs (95% CI) were 1.6 (1.1-2.4), 2.5 (1.1-6.3), 2.6 (1.5-4.5), and 1.8 (1.1-3.1), respectively. A first-degree family history of esophageal cancer was significantly associated with pancreatic NETs; AOR, 5.6 (95% CI, 1.1-29.6). There was a 70% and 130% increased risk of developing small intestinal NETs among subjects with family histories of colorectal cancer and prostate cancer, respectively. Moreover, individuals with a family history of lung cancer had a 2-fold increase in risk of developing pulmonary NETs.

Conclusions: Having a first-degree relative with any cancer in general, and NET in particular, was a risk factor for NETs. The elevated risk of developing NETs extended to individuals with a family history of other cancers (not NETs) among first-degree relatives. These results suggested that risk of NETs may be partially explained by genetic factors. (Cancer Epidemiol Biomarkers Prev 2008;17(4):959–65)
Validation of Self-Reported Colorectal Cancer Screening Behavior from a Mixed-Mode Survey of Veterans
Authors: Partin Melissa R. , Grill Joseph , Noorbaloochi Siamak , Powell Adam A. , Burgess Diana J. , Vernon Sally W. , Halek Krysten , Griffin Joan M. , van Ryn Michelle , Fisher Deborah A.
Published: April 2008

Objective: The aim of the study was to validate self-reported colorectal cancer (CRC) screening using the National Cancer Institute Colorectal Cancer Screening questionnaire.

Materials and Methods: 890 patients, ages 50 to 75 years, from the Minneapolis Veterans Affairs (VA) Medical Center were surveyed by mail. Phone administration was attempted with mail nonresponders. VA and non-VA records were combined for the reference standard. Sensitivity, specificity, concordance, and report-to-records ratio (R2R) were estimated for overall and test-specific CRC adherence among respondents providing complete medical records. Secondary analyses examined variation in estimates by patient characteristics, treatment of missing and uncertain responses, and whether a strict or liberal time interval was used for assessing concordance.

Results: Complete medical records were available for 345 of the 686 survey responders. For overall adherence, sensitivity was 0.98, specificity was 0.59, concordance was 0.88, and R2R was 1.14. Sensitivity was 0.82 for fecal occult blood test (FOBT), 0.75 for sigmoidoscopy, 0.97 for colonoscopy, and 0.63 for double-contrast barium enema (DCBE). Specificity was 0.89 for FOBT, 0.76 for sigmoidoscopy, 0.72 for colonoscopy, and 0.85 for DCBE. Concordance was >0.80 for all tests other than sigmoidoscopy (0.76). R2R was 1.31 for FOBT, 1.33 for sigmoidoscopy, 1.42 for colonoscopy, and 6.13 for DCBE. The R2R was lower for a combined sigmoidoscopy and colonoscopy measure. Overreporting was more pronounced for older, less-educated individuals with no family history of CRC. Sensitivity and R2R improved using a liberal interval and treating uncertain responses as nonadherent (versus missing), but differences were not statistically significant.

Conclusions: Self-reported CRC screening validity is generally acceptable and robust across definitional decisions, but varies by screening test and patient characteristics. (Cancer Epidemiol Biomarkers Prev 2008;17(4):768–76)
The Effects of Survey Mode and Asking About Future Intentions on Self-Reports of Colorectal Cancer Screening
Authors: Beebe Timothy J. , Jenkins Sarah M. , Anderson Kari J. , Davern Michael E. , Rockwood Todd H.
Published: April 2008

Colorectal cancer (CRC) screening rates are often ascertained via self-reports but can be subject to overreporting bias. Asking about intention to get screened before asking about past screening may minimize overreporting of cancer screening. In a statewide survey conducted from July through October of 2005, we embedded an experiment that tested the effect of question ordering (asking about future intention to get screened before or after asking about past screening; “future first” and “future second,” respectively), crossed with survey mode (mail versus telephone), on CRC screening rates. Weighted analysis focused on 752 respondents who were ages 50 years or older. We found (a) that asking about future intentions to get screened before asking about past screening (future first) statistically significantly lowers reports of past CRC screening [70.9% future second versus 58.0% future first; odds ratio (OR), 1.83; 95% confidence interval (95% CI), 1.08-3.13]; (b) that there was no main effect of survey mode; and (c) that the effect of the ordering of the future intentions item varies by survey mode. In the mailed survey, the odds of reporting past CRC screening were almost thrice greater in the future second condition compared with the future first condition (72.4% versus 49.0%, respectively; OR, 2.74; 95% CI, 1.22-6.17). In the telephone condition, the odds of reporting were only 28% higher in the future second (69.5%) condition than in the future first condition (63.9%; OR, 1.28; 95% CI, 0.64-2.57). The results suggest that asking about future intentions to get screened before the actual behavior elicits lower, and arguably more truthful reports of CRC screening but mainly in mailed surveys. (Cancer Epidemiol Biomarkers Prev 2008;17(4):785–90)
Differential Methylation of a Short CpG-Rich Sequence within Exon 1 of TCF21 Gene: A Promising Cancer Biomarker Assay
Authors: Shivapurkar Narayan , Stastny Victor , Xie Yang , Prinsen Clemens , Frenkel Eugene , Czerniak Bogdan , Thunnissen Frederik B. , Minna John D. , Gazdar Adi F.
Published: April 2008

Detection of cancer cells at early stages could potentially increase survival rates in cancer patients. Aberrant promoter hypermethylation is a major mechanism for silencing tumor suppressor genes in many kinds of human cancers. A recent report from our laboratory described the use of quantitative methylation-specific PCR assays for discriminating patients with lung cancer from those without lung cancer using lung biopsies as well as sputum samples. TCF21 is known to be essential for differentiation of epithelial cells adjacent to mesenchyme. Using restriction landmark genomic scanning, a recent study identified TCF21 as candidate tumor suppressor at 6q23-q24 that is epigenetically inactivated in lung and head and neck cancers. Using DNA sequencing technique, we narrowed down a short CpG-rich segment (eight specific CpG sites in the CpG island within exon 1) of the TCF21 gene, which was unmethylated in normal lung epithelial cells but predominantly methylated in lung cancer cell lines. We specifically targeted this short CpG-rich sequence and developed a quantitative methylation-specific PCR assay suitable for high-throughput analysis. We showed the usefulness of this assay in discriminating patients with lung cancer from those without lung cancer using biopsies and sputum samples. We further showed similar applications with multiple other malignancies. Our assay might have important implications in early detection and surveillance of multiple malignancies. (Cancer Epidemiol Biomarkers Prev 2008;17(4):995–1000)
Antiproliferative Effects by Let-7 Repression of High-Mobility Group A2 in Uterine Leiomyoma
Authors: Peng Yi , Laser Jordan , Shi Guizhi , Mittal Khush , Melamed Jonathan , Lee Peng , Wei Jian-Jun
Published: April 2008

High-mobility group A2 (HMGA2) is commonly overexpressed in large leiomyomas. HMGA2 is an important regulator of cell growth, differentiation, apoptosis, and transformation. As a predicted target of Let-7 microRNAs (Let-7s), HMGA2 can be repressed by Let-7s in vitro. MicroRNA profiling analysis revealed that Let-7s were significantly dysregulated in uterine leiomyomas: high in small leiomyomas and lower in large leiomyomas. To evaluate whether Let-7 repression of HMGA2 plays a major role in leiomyomas, we analyzed the molecular relationship of HMGA2 and Let-7s, both in vitro and in vivo. We first characterized that exogenous Let-7 microRNAs could directly repress the dominant transcript of HMGA2, HMGA2a. This repression was also identified for two cryptic HMGA2 transcripts in primary leiomyoma cultures. Second, we found that the endogenous Let-7s were biologically active and played a major role in the regulation of HMGA2. Then, we illustrated that Let-7 repression of HMGA2 inhibited cellular proliferation. Finally, we examined the expression levels of Let-7c and HMGA2 in a large cohort of leiomyomas (n = 120), and we found high levels of Let-7 and low levels of HMGA2 in small leiomyomas, and low levels of Let-7 and high levels of HMGA2 in large leiomyomas. Our findings suggest that the Let-7–mediated repression of HMGA2 mechanism can be an important molecular event in leiomyoma growth. (Mol Cancer Res 2008;6(4):663–73)
DUSP1 Is Controlled by p53 during the Cellular Response to Oxidative Stress
Authors: Liu Yu-Xin , Wang Jianli , Guo Jianfen , Wu Jingjing , Lieberman Howard B. , Yin Yuxin
Published: April 2008

p53 controls the cellular response to genotoxic stress through multiple mechanisms. We report here that p53 regulates DUSP1, a dual-specific threonine and tyrosine phosphatase with stringent substrate specificity for mitogen-activated protein kinase (MAPK). DUSP1 is a potent inhibitor of MAPK activity through dephosphorylation of MAPK. In a colon cancer cell line containing inducible ectopic p53, DUSP1 protein level is significantly increased upon activation of p53, leading to cell death in response to nutritional stress. In mouse embryo fibroblast cells, DUSP1 protein abundance is greatly increased after oxidative stress in a p53-dependent manner and also when apoptosis is triggered. We show that p53 induces the activity of a human DUSP1 regulatory region. Furthermore, p53 can physically interact with the DUSP1 regulatory region in vivo, and p53 binds to a 10-bp perfect palindromic site in this DUSP1 regulatory region. We show that overexpression of DUSP1 or inhibition of MAPK activity significantly increases cellular susceptibility to oxidative damage. These findings indicate that p53 is a transcriptional regulator of DUSP1 in stress responses. Our results reveal a mechanism whereby p53 selectively regulates target genes and suggest a way in which subgroups of those target genes might be controlled independently. (Mol Cancer Res 2008;6(4):624–33)