bluuebunny/crossref_metadata_2025 huggingface dataset:
The Effects and Interactions of Data Quality and Problem Complexity on Classification
Authors: Blake Roger , Mangiameli Paul
Published: February 2011

Data quality remains a persistent problem in practice and a challenge for research. In this study we focus on the four dimensions of data quality noted as the most important to information consumers, namely accuracy, completeness, consistency, and timeliness. These dimensions are of particular concern for operational systems, and most importantly for data warehouses, which are often used as the primary data source for analyses such as classification, a general type of data mining. However, the definitions and conceptual models of these dimensions have not been collectively considered with respect to data mining in general or classification in particular. Nor have they been considered for problem complexity. Conversely, these four dimensions of data quality have only been indirectly addressed by data mining research. Using definitions and constructs of data quality dimensions, our research evaluates the effects of both data quality and problem complexity on generated data and tests the results in a real-world case. Six different classification outcomes selected from the spectrum of classification algorithms show that data quality and problem complexity have significant main and interaction effects. From the findings of significant effects, the economics of higher data quality are evaluated for a frequent application of classification and illustrated by the real-world case.
Typing Biometrics
Authors: Ngugi Benjamin , Kahn Beverly K. , Tremaine Marilyn
Published: February 2011

The use of stolen personal-identifying information, like Social Security numbers, to commit identity fraud continues to be a major problem. The fact that an impostor can pass as the genuine user by possession of stolen identification information is a weakness in current authentication systems. Adding a biometric layer to the traditional knowledge and token-based authentication systems is one way to counter this problem. Physical biometrics, such as fingerprint systems, are highly accurate; hence, they would be the first choice for such applications but are often inappropriate. Behavioral biometrics, like biometric typing patterns, have the potential to fill this gap as another level of security but this research identified some deficiencies in performance quality. Two research streams for improvements have emerged. The first approach attempts to improve performance by building better classifiers, while the second attempts to attain the same goal by using richer identifying inputs. Both streams assume that the typing biometric patterns are stable over time. This study investigates the validity of this assumption by analyzing how students’ typing patterns behave over time. The results demonstrate that typing patterns change over time due to learning resulting in several performance quality challenges. First, the changing patterns lead to deteriorating authentication accuracy. Second, the relevancy of the reference biometric template created during training becomes questionable. Third, the deterioration in accuracy compromises the security of the whole system and fourth, the net effect brings to question whether the biometric keypad is no longer “fit for use” as an authentication system. These are critical data quality issues that need to be addressed if behavioral biometrics are to play a significant role in minimizing authentication fraud. Possible solutions to the problem, including biometric template updating and choice of uncorrelated PIN combinations, are suggested as potential topics for future research.
Frequency quorum rendezvous for fast and resilient key establishment under jamming attack
Authors: Lee Eun-Kyu , Oh Soon Y. , Gerla Mario
Published: February 2011

This paper proposes a novel Frequency Quorum Rendezvous (FQR) scheme for fast and resilient pre-key establishment in anti-jamming spread spectrum techniques. While nodes hop over own frequencies during the key establishment phase, using a quorum system improves their rendezvous probability and reduces time latency.
Improved AP association management using machine learning
Authors: Sun Tingting , Trappe Wade , Zhang Yanyong
Published: February 2011

We propose a distributed scheme by which nodes select an appropriate access point to associate with using each individual device's channel utilization. Specifically, we define a new metric, channel utilization, which is defined as the ratio of required bandwidth to available bandwidth estimation. By incorporating channel utilization into the access point selection protocol, we effectively reduce unnecessary reassociations and improve upper layer performance in terms of throughput, packet delivery delay, etc. We further enhance our protocol by using reinforcement learning to adapt the scheduling of probing neighboring access points (APs), ultimately reducing probing overhead by learning from past experience whether the current operational scenario would suffer from undesirable overhead. When channel utilization is combined with adaptive probing, we observed a significant performance improvement compared to traditional association approaches.
Mobile TCP usage characteristics and the feasibility of network migration without infrastructure support
Authors: Rahmati Ahmad , Shepard Clayton , Nicoara Angela , Zhong Lin , Singh Jatinder Pal
Published: February 2011

In this poster we describe initial findings regarding Internet usage characteristics, in particular TCP flows from a field study with 27 iPhone 3GS users. We present details regarding their usage characteristics, and provide a solution for migrating flows between different networks and/or network interfaces without requiring infrastructure support or changes to current applications and protocols, with minimal impact to the user.
Proximity-based trust-advisor using encounters
Authors: Kumar Udayan , Helmy Ahmed
Published: February 2011

No trust tantamounts to no communication in DTN and mobile ad-Hoc networks. In this work we propose a novel encounter-based trust framework based on the principle of homophiliy. We propose 4 trust advisors and analyze their performance using WLAN traces. We find that our filters not only provide meaningful trust but also improve network performance in the presence of selfish nodes.
Spectral analysis of periodicity and regularity for mobile encounters in delay tolerant networks
Authors: Moon Sungwook , Helmy Ahmed
Published: February 2011

We study the encounter patterns of mobile devices to understand the potential of mobile nodes as messengers in delay tolerant networks. Specifically, we examine the extensive network and encounter traces that reflect mobility of communication devices, using spectral analysis to unearth hidden repetitive patterns of them. We discover strong presence of periodic encounter patterns between mobile users, particularly weekly pattern. Our results also show different location visiting ratio by more than 10 percent between regularly encountering pairs and others at 77 percent of the locations.
SUNSHINE
Authors: Zhang Jingyao , Tang Yi , Hirve Sachin , Iyer Srikrishna , Schaumont Patrick , Yang Yaling
Published: February 2011

In this paper, we describe the design and implementation of SUNSHINE, a scalable hardware-software simulator for sensornet applications. SUNSHINE captures the performance of network protocols, software and hardware up to cycle-level accuracy. SUNSHINE solves challenging design problems, including data exchanges and time synchronization across different simulation domains and simulation accuracy levels. SUNSHINE also provides hardware specification scheme for simulating flexible and customized hardware designs. An experiment demonstrates that SUNSHINE is an efficient tool for sensornet prototyping.
The impact of topology in robust routing on wireless mesh networks
Authors: Wellons Jonathan , Xue Yuan
Published: February 2011

Topology is an essential consideration in the performance of a Wireless Mesh Network, going hand-in-hand with routing. Existing works on routing typically assume topology is a known input which is given in advance and compute routes accordingly. However, in reality considerable freedom exists in node placement with the possibility of creating topologies of varying performances. As the joint topology and routing problem is largely an open issue for conventional wireless mesh networks, these choices may harbor a significant unrealized potential for improvements. In this paper, we explore the impact of node distribution on routing performance in a wireless mesh network by using a novel model to parameterize node placement in a topology. We then evaluate our model using a simulation study and discover a strong correlation between parameter choice and network performance.
Traffic shaping in wireless home networks
Authors: Srikantha Pirathayini , Carrera Marianna , May Martin
Published: February 2011

Many devices commonly found in wireless home networks such as smartphones, gaming consoles and media servers generate real-time traffic with stringent performance requirements. Since the wireless medium is mostly accessed in a distributed manner (DCF), sensitive traffic needs to be "protected". This work investigates how mechanisms defined in the WiFi standard such as virtual carrier sensing and CTS frames can enable this without requiring any modifications to end devices. ns-3 simulations of this scheme in typical wireless home network configurations show significant performance improvement in the delivery rate of prioritized nodes compared to those using plain DCF.
Workshop on semantic data management
Authors: Krummenacher Reto , Aberer Karl , Kiryakov Atanas , Kanagasabai Rajaraman
Published: February 2011

The InternationalWorkshop on Semantic Data Management (SemData) was held in Singapore co-located with the VLDB Conference 2010, with the goal of serving as a platform for the discussion and investigation of various aspects related to semantic databases and data managementin the large. The workshop was a full-day event featuring two research sessions, one industry session and a panel discussion, and attracted over 25 attendees. This report summarizes the key topics presented, interesting ideas discussed and the new perspectives identified during the workshop.
Towards a computational transportation science
Authors: Winter Stephan , Sester Monika , Wolfson Ouri , Geers Glenn
Published: February 2011

This workshop report sets out to define Computational Transportation Science as the science behind intelligent transportation systems. In particular it develops a first research agenda for this science, illustrating its unique challenges and putting them to public debate.
Automatic variation-point identification in function-block-based models
Authors: Ryssel Uwe , Ploennigs Joern , Kabitzsch Klaus
Published: February 2011

Function-block-based modeling is often used to develop embedded systems, particularly as system variants can be developed rapidly from existing modules. Generative approaches can simplify the handling and development of the resulting high variety of function-block-based models. But they often require the development of new generic models that do not utilize existing ones. Reusing existing models will significantly decrease the effort to apply generative programming. This work introduces an automatic approach to recognize variants in a set of models and identify the variation points and their dependencies within variants. As result it offers automatically generated feature models and ICCL content to regenerate the given variants.
A component-based run-time evolution infrastructure for resource-constrained embedded systems
Authors: Navas Juan F. , Babau Jean-Philippe , Pulou Jacques
Published: February 2011

This paper deals with embedded systems software and the modification of its architecture and behavior at execution-time. Incautious implementation of these features demands both heavy memory and performance overrun. To accomplish such software evolution activities in resource-constrained embedded systems, we propose a component-based run-time evolution infrastructure that reconciles richness of evolution alternatives and performance requirements. Our proposal is based on off-site components reifications, which are representations of components that allow us to treat evolution concerns remotely. Hence, the workload to be processed by the embedded device is alleviated. Memory and processor-time resources consumption evaluation on a real-world scenario show the efficiency and pertinence of our approach.
Composition of dynamic analysis aspects
Authors: Tanter Éric , Moret Philippe , Binder Walter , Ansaloni Danilo
Published: February 2011

Aspect-oriented programming provides a convenient high-level model to define several kinds of dynamic analyses, in particular thanks to recent advances in exhaustive weaving in core libraries. Casting dynamic analyses as aspects allows the use of a single weaving infrastructure to apply different analyses to the same base program, simultaneously. However, even if dynamic analysis aspects are mutually independent, their mere presence perturbates the observations of others: this is due to the fact that aspectual computation is potentially visible to all aspects. Because current aspect composition approaches do not address this kind of computational interference, combining different analysis aspects yields at best unpredictable results. It is also impossible to flexibly combine various analyses, for instance to analyze an analysis aspect. In this paper we show how the notion of execution levels makes it possible to effectively address these composition issues. In order to realize this approach, we explore the practical and efficient integration of execution levels in a mainstream aspect language, AspectJ. We report on a case study of composing two out-of-the-box analysis aspects in a variety of ways, highlighting the benefits of the approach.
Lightweight modular staging
Authors: Rompf Tiark , Odersky Martin
Published: February 2011

Software engineering demands generality and abstraction, performance demands specialization and concretization. Generative programming can provide both, but the effort required to develop high-quality program generators likely offsets their benefits, even if a multi-stage programming language is used.

We present lightweight modular staging, a library-based multi-stage programming approach that breaks with the tradition of syntactic quasi-quotation and instead uses only types to distinguish between binding times. Through extensive use of component technology, lightweight modular staging makes an optimizing compiler framework available at the library level, allowing programmers to tightly integrate domain-specific abstractions and optimizations into the generation process.

We argue that lightweight modular staging enables a form of language virtualization, i.e. allows to go from a pure-library embedded language to one that is practically equivalent to a stand-alone implementation with only modest effort.
Domain-specific language integration with compile-time parser generator library
Authors: Porkolab Zoltán , Sinkovics Ábel
Published: February 2011

Smooth integration of domain-specific languages into a general purpose host language requires absorbing of domain code written in arbitrary syntax. The integration should cause minimal syntactical and semantic overhead and introduce minimal dependency on external tools. In this paper we discuss a DSL integration technique for the C++ programming language. The solution is based on compile-time parsing of the DSL code. The parser generator is a C++ template metaprogram reimplementation of a runtime Haskell parser generator library. The full parsing phase is executed when the host program is compiled. The library uses only standard C++ language features, thus our solution is highly portable. As a demonstration of the power of this approach, we present a highly efficient and type-safe version of printf and the way it can be constructed using our library. Despite the well known syntactical difficulties of C++ template metaprograms, building embedded languages using our library leads to self-documenting C++ source code.
ABI compatibility through a customizable language
Authors: Atkinson Kevin , Flatt Matthew , Lindstrom Gary
Published: February 2011

ZL is a C++-compatible language in which high-level constructs, such as classes, are defined using macros over a C-like core language. This approach makes many parts of the language easily customizable. For example, since the class construct can be defined using macros, a programmer can have complete control over the memory layout of objects. Using this capability, a programmer can mitigate certain problems in software evolution such as fragile ABIs (Application Binary Interfaces) due to software changes and incompatible ABIs due to compiler changes. In this paper, we outline the problem of fragile and incompatible ABIs and show how ZL can be used to solve them.
JEqualityGen
Authors: Grech Neville , Rathke Julian , Fischer Bernd
Published: February 2011

Manually implementing equals (for object comparisons) and hashCode (for object hashing) methods in large software projects is tedious and error-prone. This is due to many special cases, such as field shadowing, comparison between different types, or cyclic object graphs. Here, we present JEqualityGen, a source code generator that automatically derives implementations of these methods.

JEqualityGen proceeds in two states: it first uses source code reflection in MetaAspectJ to generate aspects that contain the method implementations, before it uses weaving on the bytecode level to insert these into the target application. JEqualityGen generates not only correct, but efficient source code that on a typical large-scale Java application exhibits a performance improvement of more than two orders of magnitude in the equality operations generated, compared to an existing system based on runtime reflection. JEqualityGen achieves this by generating runtime profiling code that collects data. This enables it to generate optimised method implementations in a second round.
A Comparative Study of Two Quantum Chemical Descriptors in Predicting Toxicity of Aliphatic Compounds towardsTetrahymena pyriformis
Authors: Pandith Altaf Hussain , Giri S. , Chattaraj P. K.
Published: February 2011

Quantum chemical parameters such as LUMO energy, HOMO energy, ionization energy (I), electron affinity (A), chemical potential (μ), hardness (η) electronegativity (χ), philicity (ωα), and electrophilicity (ω) of a series of aliphatic compounds are calculated at the B3LYP/6-31G(d) level of theory. Quantitative structure-activity relationship (QSAR) models are developed for predicting the toxicity (pIGC50) of 13 classes of aliphatic compounds, including 171 electron acceptors and 81 electron donors, towardsTetrahymena pyriformis. The multiple linear regression modeling of toxicity of these compounds is performed by using the molecular descriptor log P(1-octanol/water partition coefficient) in conjunction with two other quantum chemical descriptors, electrophilicity (ω) and energy of the lowest unoccupied molecular orbital (ELUMO). A comparison is made towards the toxicity predicting the ability of electrophilicity (ω) versusELUMOas a global chemical reactivity descriptor in addition to log P. The former works marginally better in most cases. There is a slight improvement in the quality of regression by changing the unit ofIGC50from mg/L to molarity and by removing the racemates and the diastereoisomers from the data set.
An Assessment of the Literature and Recent Developments on the Shallow Wake in an Open Channel Flow
Authors: Singha Arindam , Balachandar Ramaswami
Published: February 2011

Although shallow flows are very abundant both in nature and in flows of technological importance, their effective characterization started only recently. This type of flow, being vertically confined, exhibits some unique features, which are absent in conventional unconfined flows. A brief review of the related research articles indicates that the exploration of the shallow wake had occurred in three distinct chronological phases. Initially, almost all investigations were aimed at exploring the differences between shallow flows and unconfined flows. Given the differences, the second phase of investigations was mostly concerned with identifying the sources of these differences found already. The third and most recent group of investigations attempted to correlate the flow topology with the extent of the confinement and focused on more applied areas like control of wake instability and consequent effects on drag reduction, and the effect of the coherent structures on species transport. The present paper is intended to present retrospect of the seminal investigations regarding shallow flows, and summarizes the key results from widely ranging studies. Another motivation of the present paper is to provide a basis for future research of shallow wake.
Adiposity Measures and Menstrual Cycle: Do We Envisage a Relation?
Authors: Sinha Rashmi , Kapoor Anup Kumar , Kapoor Satwanti
Published: February 2011

The study aims to see the relationship between menstrual cycle and adiposity measures in Indian populations as menstrual cycle length has an important bearing on fertility and health of women. 415 premenopausal women in the ages 22–50 years residing in Delhi, India constituted the data. The adiposity was assessed by BMI as well as by using Bio-electric impedance method. The information regarding their physical activity pattern and menstrual cycle was recorded, and age at menarche was obtained through recall method. None of the underweight category women had menstrual cycle of less than 25 days. A decrease in body mass index and an increase in the age at menarche were found with the increase in the duration of menstrual cycle. The majority of women with 25–35 days duration of menstrual cycle in the present study were distributed in all the categories of BMI. Age was found to have no effect on longer cycle. The majority of women were in moderately physically active group and experienced menstrual cycle duration of 25–35 days. It is of utmost importance to identify the effects of moderate levels of physical activity, body mass index, and age at menarche on the menstrual cycle to enable the normal reproductive health of women.
Chondrosarcoma: With Updates on Molecular Genetics
Authors: Kim Mi-Jung , Cho Kyung-Ja , Ayala Alberto G. , Ro Jae Y.
Published: February 2011

Chondrosarcoma (CHS) is a malignant cartilage-forming tumor and usually occurs within the medullary canal of long bones and pelvic bones. Based on the morphologic feature alone, a correct diangosis of CHS may be difficult, Therefore, correlation of radiological and clinicopathological features is mandatory in the diagnosis of CHS. The prognosis of CHS is closely related to histologic grading, however, histologic grading may be subjective with high inter-observer variability. In this paper, we present histologic grading system and clinicopathological and radiological findings of conventional CHS. Subtypes of CHSs, such as dedifferentiated, mesenchymal, and clear cell CHSs are also presented. In addition, we introduce updated cytogenetic and molecular genetic findings to expand our understanding of CHS biology. New markers of cell differentiation, proliferation, and cell signaling might offer important therapeutic and prognostic information in near future.
Prevalence of Thinness among Santal Preschool Children Using New Body Mass Index Cut-Off Points
Authors: Das Subal , Bose Kaushik
Published: February 2011

A community-based cross-sectional study was undertaken to determine the prevalence of undernutrition using body mass index (BMI) among 2–6-year Santal preschool children of Purulia District, West Bengal, India. A total of 251 (116 boys and 135 girls) children from 12 villages were measured. Commonly used indicators, that is, weight, height, and BMI, were used to evaluate the nutritional status. More boys (59.5%) than girls (53.3%), based on BMI, were undernourished. Significant age differences in weight
(F=44.29∗∗∗; df=3), height (F=58.48∗∗∗; df=3), and BMI (F=3.52∗∗∗; df=3) among boys were observed. Similarly, significant differences between ages in mean weight (F=56.27∗∗∗; df=3), height (F=64.76∗∗∗; df=3), and BMI (F=2.62∗∗∗; df=3) were observed among the girls. The present study revealed that the nutritional status of the preschool children of Santal tribal community of
these villages was poor with very high rate of thinness in boys and girls (59.5% and 53.3%, resp.).
A Coupled Calculation Suite for Atucha II Operational Transients Analysis
Authors: Mazzantini Oscar , Schivo Miguel , Di Césare Julián , Garbero Ricardo , Rivero Matías , Theler Germán
Published: February 2011

While more than a decade ago reactor and thermal hydraulic calculations were tedious and often needed a lot of approximations and simplifications that forced the designers to take a very conservative approach, computational resources available nowadays allow engineers to cope with increasingly complex problems in a reasonable time. The use of best‐estimate calculations provides tools to justify convenient engineering margins, reduces costs, and maximises economic benefits. In this direction, a suite of coupled best‐estimate specific calculation codes was developed to analyse the behaviour of the Atucha II nuclear power plant in Argentina. The developed tool includes three‐dimensional spatial neutron kinetics, a channel‐level model of the core thermal hydraulics with subcooled boiling correlations, a one‐dimensional model of the primary and secondary circuits including pumps, steam generators, heat exchangers, and the turbine with all their associated control loops, and a complete simulation of the reactor control, limitation, and protection system working in closed‐loop conditions as a faithful representation of the real power plant. In the present paper, a description of the coupling scheme between the codes involved is given, and some examples of their application to Atucha II are shown.
Severe Renal Hemorrhage in a Pregnant Woman Complicated with Antiphospholipid Syndrome: A Case Report
Authors: Kawaguchi Shohei , Izumi Kouji , Nohara Takahiro , Miyagi Tohru , Konaka Hiroyuki , Mizokami Atsushi , Koh Eitetsu , Namiki Mikio
Published: February 2011

Antiphospholipid syndrome is a systemic autoimmune disease with thrombotic tendency. Consensus guidelines for pregnancy with antiphospholipid syndrome recommend low-dose aspirin combined with unfractionated or low-molecular-weight heparin because antiphospholipid syndrome causes habitual abortion. We report a 36-year-old pregnant woman diagnosed with antiphospholipid syndrome receiving anticoagulation treatment. The patient developed left abdominal pain and gross hematuria at week 20 of pregnancy. An initial diagnosis of left ureteral calculus was made. Subsequently abdominal-pelvic computed tomography was required for diagnosis because of the appearance of severe contralateral pain. Computed tomography revealed serious renal hemorrhage, and ureteral stent placement and pain control by patient-controlled analgesia were required. After treatment, continuance of pregnancy was possible and vaginal delivery was performed safely. This is the first case report of serious renal hemorrhage in a pregnant woman with antiphospholipid syndrome receiving anticoagulation treatment and is an instructive case for urological and obstetrical practitioners.
Targeting the Replication Checkpoint Using SCH 900776, a Potent and Functionally Selective CHK1 Inhibitor Identified via High Content Screening
Authors: Guzi Timothy J. , Paruch Kamil , Dwyer Michael P. , Labroli Marc , Shanahan Frances , Davis Nicole , Taricani Lorena , Wiswell Derek , Seghezzi Wolfgang , Penaflor Ervin , Bhagwat Bhagyashree , Wang Wei , Gu Danling , Hsieh Yunsheng , Lee Suining , Liu Ming , Parry David
Published: February 2011

Checkpoint kinase 1 (CHK1) is an essential serine/threonine kinase that responds to DNA damage and stalled DNA replication. CHK1 is essential for maintenance of replication fork viability during exposure to DNA antimetabolites. In human tumor cell lines, ablation of CHK1 function during antimetabolite exposure led to accumulation of double-strand DNA breaks and cell death. Here, we extend these observations and confirm ablation of CHK2 does not contribute to these phenotypes and may diminish them. Furthermore, concomitant suppression of cyclin-dependent kinase (CDK) activity is sufficient to completely antagonize the desired CHK1 ablation phenotypes. These mechanism-based observations prompted the development of a high-content, cell-based screen for γ-H2AX induction, a surrogate marker for double-strand DNA breaks. This mechanism-based functional approach was used to optimize small molecule inhibitors of CHK1. Specifically, the assay was used to mechanistically define the optimal in-cell profile with compounds exhibiting varying degrees of CHK1, CHK2, and CDK selectivity. Using this approach, SCH 900776 was identified as a highly potent and functionally optimal CHK1 inhibitor with minimal intrinsic antagonistic properties. SCH 900776 exposure phenocopies short interfering RNA-mediated CHK1 ablation and interacts synergistically with DNA antimetabolite agents in vitro and in vivo to selectively induce dsDNA breaks and cell death in tumor cell backgrounds. Mol Cancer Ther; 10(4); 591–602. ©2011 AACR.
Altered Folate Availability Modifies the Molecular Environment of the Human Colorectum: Implications for Colorectal Carcinogenesis
Authors: Protiva Petr , Mason Joel B. , Liu Zhenhua , Hopkins Michael E. , Nelson Celeste , Marshall James R. , Lambrecht Richard W. , Pendyala Swaroop , Kopelovich Levy , Kim Myungjin , Kleinstein Steven H. , Laird Peter W. , Lipkin Martin , Holt Peter R.
Published: February 2011

Low folate status increases colorectal cancer risk. Paradoxically, overly abundant folate supplementation, which is not uncommon in the United States, may increase risk. The mechanisms of these effects are unknown. We conducted two translational studies to define molecular pathways in the human colon altered either by folate supplementation or by dietary folate depletion (followed by repletion). In the first study, 10 healthy, at-risk volunteers (with documented stable/normal folate intake) received supplemental folic acid (1 mg/d) for 8 weeks. In the second study, 10 similar subjects were admitted to a hospital as inpatients for 12 weeks to study folate depletion induced by a low folate diet. A repletion regimen of folic acid (1 mg/d) was provided for the last 4 of these weeks. Both studies included an 8-week run-in period to ensure stabilized folate levels prior to intervention. We obtained 12 rectosigmoid biopsies (from 4 quadrants of normal-appearing mucosa 10–15 cm from the anal verge) at baseline and at measured intervals in both studies for assessing the primary endpoints: genome-wide gene expression, genomic DNA methylation, promoter methylation (depletion/repletion study only), and p53 DNA strand breaks. Serum and rectosigmoid folate concentrations accurately tracked all changes in folate delivery (P < 0.05). In the first study, gene array analysis revealed that supplementation upregulated multiple inflammation- and immune-related pathways in addition to altering several 1-carbon–related enzymes (P < 0.001). In the second study, folate depletion downregulated genes involved in immune response, inflammation, the cell cycle, and mitochondrial/energy pathways; repletion reversed most of these changes. However, changes in gene expression after repletion in the second study (involving immune response and inflammation) did not reach the levels seen after supplementation in the first study. Neither genomic nor promoter-specific DNA methylation changed during the course of the depletion/repletion protocol, and genomic methylation did not change with supplementation in the first study. p53 DNA strand breaks increased with depletion after 12 weeks. In sum, depletion downregulates, whereas repletion or supplementation upregulates pathways related to inflammation and immune response. These findings provide novel support to the concept that excessive folate supplementation might promote colorectal carcinogenesis by enhancing proinflammatory and immune response pathways. These results indicate that modest changes in folate delivery create substantial changes in the molecular milieu of the human colon. Cancer Prev Res; 4(4); 530–43. ©2011 AACR.
Is Hypothermia After Cardiac Arrest Effective in Both Shockable and Nonshockable Patients?
Authors: Dumas Florence , Grimaldi David , Zuber Benjamin , Fichet Jérôme , Charpentier Julien , Pène Frédéric , Vivien Benoît , Varenne Olivier , Carli Pierre , Jouven Xavier , Empana Jean-Philippe , Cariou Alain
Published: February 2011

Background—

Although the level of evidence of improvement is significant in cardiac arrest patients resuscitated from a shockable rhythm (ventricular fibrillation or pulseless ventricular tachycardia [VF/V
t
]), the use of therapeutic mild hypothermia (TMH) is more controversial in nonshockable patients (pulseless electric activity or asystole [PEA/asystole]). We therefore assessed the prognostic value of hypothermia for neurological outcome at hospital discharge according to first-recorded cardiac rhythm in a large cohort.

Methods and Results—

Between January 2000 and December 2009, data from 1145 consecutive out-of-hospital cardiac arrest patients in whom a successful resuscitation had been achieved were prospectively collected. The association of TMH with a good neurological outcome at hospital discharge (cerebral performance categories level 1 or 2) was quantified by logistic regression analysis. TMH was induced in 457/708 patients (65%) in VF/V
t
and in 261/437 patients (60%) in PEA/asystole. Overall, 342/1145 patients (30%) reached a favorable outcome (cerebral performance categories level 1 or 2) at hospital discharge, respectively 274/708 (39%) in VF/V
t
and 68/437 (16%) in PEA/asystole (
P
<0.001). After adjustment, in VF/V
t
patients, TMH was associated with increased odds of good neurological outcome (adjusted odds ratio, 1.90; 95% confidence interval, 1.18 to 3.06) whereas in PEA/asystole patients, TMH was not significantly associated with good neurological outcome (adjusted odds ratio, 0.71; 95% confidence interval, 0.37 to 1.36).

Conclusions—

In this large cohort of cardiac arrest patients, hypothermia was independently associated with an improved outcome at hospital discharge in patients presenting with VF/V
t
. By contrast, TMH was not associated with good outcome in nonshockable patients. Further investigations are needed to clarify this lack of efficiency in PEA/asystole.
Soluble Form of the (Pro)Renin Receptor Is Augmented in the Collecting Duct and Urine of Chronic Angiotensin II–Dependent Hypertensive Rats
Authors: Gonzalez Alexis A. , Lara Lucienne S. , Luffman Christina , Seth Dale M. , Prieto Minolfa C.
Published: February 2011

Renin synthesis and secretion by principal cells of the collecting duct are enhanced in angiotensin (Ang) II–dependent hypertension. The presence of renin/(pro)renin and its receptor, the (pro)renin receptor ([P]RR), in the collecting duct may provide a pathway for Ang I generation with further conversion to Ang II. To assess whether (P)RR activation occurs during Ang II–dependent hypertension, we examined renal (P)RR levels and soluble (P)RR excretion in the urine of chronic Ang II–infused rats (80 ng/min; for 2 weeks; n=10) and sham-operated rats (n=10). Systolic blood pressure and Ang II levels in the plasma and kidney were increased whereas plasma renin activity was suppressed in Ang II–infused rats. Renal (P)RR transcripts were upregulated in the cortex and medulla of Ang II–infused rats. (P)RR immunoreactivity in collecting duct cells and the protein levels of the full-length form (37-kDa band) were significantly decreased in the medulla of Ang II–infused rats. The soluble (P)RR (28-kDa band) was detected in the renal medulla and urine samples of Ang II–infused rats, which also showed increases in urinary renin content. To determine whether the soluble (P)RR could stimulate Ang I formation, urine samples were incubated with recombinant human (pro)renin. Urine samples of Ang II–infused rats exhibited increased Ang I formation compared with sham-operated rats. Thus, in chronic Ang II–infused rats, the catalytic activity of the augmented renin produced in the collecting duct may be enhanced by the intraluminal soluble (P)RR and cell-surface located (P)RR, thus contributing to enhanced intratubular Ang II formation.
Handle Region Peptide Counteracts the Beneficial Effects of the Renin Inhibitor Aliskiren in Spontaneously Hypertensive Rats
Authors: van Esch Joep H.M. , van Veghel Richard , Garrelds Ingrid M. , Leijten Frank , Bouhuizen Angelique M. , Danser A.H. Jan
Published: February 2011

To investigate whether the putative (pro)renin receptor blocker, the handle region peptide (HRP), exerts effects on top of the blood pressure–lowering and cardioprotective effects of the renin inhibitor aliskiren, spontaneously hypertensive rats were implanted with telemetry transmitters to monitor heart rate and mean arterial pressure (MAP). After a 2-week recovery period, vehicle, aliskiren, HRP (100 and 1 mg/kg per day, respectively), and HRP+aliskiren were infused for 3 weeks using osmotic minipumps. Subsequently, the heart was removed to study coronary function according to Langendorff. Baseline MAP and heart rate in vehicle-treated rats were 146±3 mm Hg and 326±4 bpm. HRP did not affect MAP, whereas aliskiren and HRP+aliskiren lowered MAP (by maximally 29±2 and 20±1 mm Hg, respectively) without affecting heart rate. Aliskiren significantly reduced MAP throughout the 3-week infusion period, whereas the blood pressure–lowering effect of HRP+aliskiren returned to baseline within 2 weeks of treatment. In comparison with vehicle, aliskiren increased the endothelium-dependent response to bradykinin and decreased the response to angiotensin II in the coronary circulation, whereas these responses were not altered after treatment with HRP or HRP+aliskiren. HRP did not alter plasma renin activity, plasma angiotensin levels, or the renal angiotensin content, either alone or on top of aliskiren, nor did it alter the aliskiren-induced decrease in renal Ang II type 1 receptor expression. Yet, it did reverse the aliskiren-induced reduction in cardiomyocyte area, without affecting this area when given alone. In conclusion, HRP counteracts the beneficial effects of aliskiren on blood pressure, coronary function, and cardiac hypertrophy in an angiotensin-independent manner.
Radiometer and Profiler Analysis of the Effects of a Bore and a Solitary Wave on the Stability of the Nocturnal Boundary Layer
Authors: Coleman Timothy A. , Knupp Kevin R.
Published: February 2011

This study uses data from a microwave profiling radiometer (MPR), along with 915-MHz wind profiler, Doppler radar, and surface data to quantify the kinematic and thermodynamic effects of two wave features, an undular bore and a soliton, on the nocturnal boundary layer (NBL) at high temporal resolution. Both wave features passed directly over the MPR and the wind profiler, allowing for detailed analyses. The effects of the wave features on the convective environment are examined, and convective initiation (CI) associated with the wave features is discussed.

The undular bore was illustrated well in Doppler velocity data, and profiler measurements indicated that it produced four wavelengths of upward and downward motion. MPR-derived time–height sections of potential temperature and mixing ratio showed an increase in the depth of the stable boundary layer, along with a decrease in stability, partially associated with mixing of the NBL. The soliton produced a temporary decrease in the depth of the NBL, and also produced destabilization. Trajectory analyses were performed assuming the wave features were two-dimensional, allowing a time-to-space conversion of profiler data. Trajectory analyses, in addition to propagation speed, confirm that the wave features were indeed a bore and a soliton, and that there was vertical divergence in the NBL, likely associated with the decrease in static stability.

MPR data were also used to produce time series of convective parameters, including CAPE, convective inhibition (CIN), and the level of free convection (LFC). The CIN was initially too large for free convection despite sufficient CAPE, but MPR data showed that the CIN decreased by more than 50% upon passage of the bore, and again with the soliton. The waves also decreased the LFC due to cooling above the NBL and slight warming near the surface in the bore. Both the reduction in CIN and the lowering of the LFC made convection more likely. Convective initiation occurred behind both wave features, and the vertical motion provided by the waves may have also aided in this CI.
Radical Orthodoxy
Authors: Grumett David
Published: February 2011

The newest theological direction to be covered in this series, Radical Orthodoxy was launched in 1999 by Cambridge theologians John Milbank, Catherine Pickstock and Graham Ward. It sought to contest secular culture and the sidelining of theology from academic and public discourse by demonstrating the insufficiency of any account of reality that excluded religion or theology. Key themes have included culture, participation, gift, liturgy, erotic desire and the body.
Viscoelasticity of Human Oral Mucosa
Authors: Sawada A. , Wakabayashi N. , Ona M. , Suzuki T.
Published: February 2011

The dynamic behavior of oral soft tissues supporting removable prostheses is not well understood. We hypothesized that the stress and strain of the mucosa exhibited time-dependent behavior under masticatory loadings. Displacement of the mucosa on the maxillary residual ridge was measured in vivo by means of a magnetic actuator/sensor under vertical loading in partially edentulous individuals. Subject-specific finite element models of homogeneous bone and mucosa were constructed based on computed tomography images. A mean initial elastic modulus of 8.0 × 10–5 GPa and relaxation time of 494 sec were obtained from the curve adaptation of the finite element output to the in vivo time-displacement relationship. Delayed increase of the maximum compressive strain on the surface of the mucosa was observed under sustained load, while the maximum strain inside the mucosa was relatively low and uninfluenced by the duration of the load. The compressive stress showed a slight decrease with sustained load, due to stress relaxation of the mucosa. On simulation of cyclic load, the increment of the maximum strain and the evidence of residual strain were revealed after each loading. The results support our hypothesis, and suggest that sustained and repetitive loads accumulate as surface strain on the mucosa.
Militarized territorial disputes
Authors: Wiegand Krista E
Published: February 2011

States involved in territorial disputes are more likely initiate militarized interstate disputes to threaten or use force (MIDs) compared to states involved in other types of interstate disputes, when the disputed territory has strategic or ethnic value, and when the opposing states are contiguous, rivals, or have relative power parity. Though useful, these factors are static or rarely change over time, so they cannot explain the timing of an MID in a territorial dispute. It is not clear why a challenger state would threaten or use force at one point in the dispute, but not at another point. This study proposes that challenger states sometimes use MIDs not only to signal resolve to the opposing state in the territorial dispute, but to credibly demonstrate resolve to other adversaries in other disputes – an attempt to transfer reputation for resolve. To tackle the debate about transferability of reputation for resolve, the study empirically analyzes all territorial disputes from 1919 to 1995 and finds support that challenger states are more likely to initiate territorial MIDs as costly signals of resolve and credibility around the same time as another MID with a different adversary. Further analysis indicates that in terms of intensity level, challenger states are more likely to use threats, displays of force, or low intensity uses of force when initiating an MID to signal resolve to other states.
Just part of the game? Arms races, rivalry, and war
Authors: Rider Toby J , Findley Michael G , Diehl Paul F
Published: February 2011

In this study, we look at the relationship of arms races to war, with appropriate consideration of rivalries. Are arms races more common in rivalries than in lesser competitions? Are they merely a consequence of rivalry competitions? How do the patterns of arms races map with those of war in rivalries? We explore these concerns with an empirical examination of rivalry and non-rivalry populations in the 1816–2000 period. In brief, we find that: arms races occur most frequently in the context of enduring rivalries; arms races are more likely in the middle and later stages of rivalry; the frequency of arms races is higher in rivalries with war than rivalries that do not experience war; and only when arms races occur in the later phases of rivalries is there an increased chance of war. Our study narrows the scope of the arms race–war relationship relative to past studies, demonstrating that the arms race–war relationship is conditional on rivalry processes.
Urban poverty and support for Islamist terror
Authors: Mousseau Michael
Published: February 2011

Survey respondents in 14 countries representing 62% of the world’s Muslim population indicate that approval of Islamist terror is not associated with religiosity, lack of education, poverty, or income dissatisfaction. Instead, it is associated with urban poverty. These results are consistent with the thesis that Islamist terrorists obtain support and recruits from the urban poor, who pursue their economic interests off the market in politics in collective groups. These groups compete over state rents, so a gain for one group is a loss for another, making terrorism of members of out-groups rational. The rise of militant Islam can be attributed to high rates of urbanization in many Muslim countries in recent decades, which fosters violence as rising groups seek to dislodge prior groups entrenched in power. Rising group leaders also compete over new urban followers, so they promote fears of out-groups and package in-group identities in ways that ring true for the urban poor. Because many of the urban poor are migrants from the countryside, popular packages are those which identify with traditional rural values and distinguish enemies as those associated with urban modernity and the secular groups already in power. Imams have an incentive to preach what audiences want to hear, so a mutated in-group version of Islam – Islamism – struck a chord in several large cities around the globe at the same time. With globalization of the media, in many developing countries the West is widely (albeit wrongly) perceived as an inimical out-group associated with urban modernity. The best political strategy to limit support and recruits for Islamist terrorist groups is to enhance the economic opportunities available for the urban poor and to provide them the needed services, such as access to health care and education, that many currently obtain from Islamist groups.