bluuebunny/crossref_metadata_2025 huggingface dataset:
Efficient Walking Speed Optimization of a Humanoid Robot
Authors: Hemker T. , Stelzer M. , von Stryk O. , Sakamoto H.
Published: January 2009

The development of optimized motions of humanoid robots that guarantee fast and also stable walking is an important task, especially in the context of autonomous soccer-playing robots in RoboCup. We present a walking motion optimization approach for the humanoid robot prototype HR18 which is equipped with a low-dimensional parameterized walking trajectory generator, joint motor controller and an internal stabilization. The robot is included as hardware-in-the-loop to define a low-dimensional black-box optimization problem. In contrast to previously performed walking optimization approaches, we apply a sequential surrogate optimization approach using stochastic approximation of the underlying objective function and sequential quadratic programming to search for a fast and stable walking motion. This is done under the conditions that only a small number of physical walking experiments should have to be carried out during the online optimization process. For the identified walking motion for the considered 55 cm tall humanoid robot, we measured a forward walking speed of more than 30 cm s-1 . With a modified version of the robot, even more than 40 cm s-1 could be achieved in permanent operation.
Proxy-based Sliding Mode Control of a Planar Pneumatic Manipulator
Authors: Van Damme Michäel , Vanderborght Bram , Verrelst Bjorn , Van Ham Ronald , Daerden Frank , Lefeber Dirk
Published: January 2009

For a robotic system that shares its workspace with humans and physically interacts with them, safety is of paramount importance. In order to build a safe system, safety has to be considered in both hardware and software (control). In this paper, we present the safe control of a two-degree-of-freedom planar manipulator actuated by Pleated Pneumatic Artificial Muscles. Owing to its low weight and inherent compliance, the system hardware has excellent safety characteristics. In traditional control methods, safety and good tracking are often impossible to combine. This is different in the case of Proxy-Based Sliding Mode Control (PSMC), a novel control method introduced by Kikuuwe and Fujimoto. PSMC combines responsive and accurate tracking during normal operation with smooth, slow and safe recovery from large position errors. It can also make the system behave compliantly to external disturbances. We present both task- and joint-space implementations of PSMC applied to the pneumatic manipulator, and compare their performance with PID control. Good tracking results are obtained, especially with the joint-space implementation. Safety is evaluated by means of the Head Injury Criterion and by the maximum interaction force in the case of collision. It is found that in spite of the hardware safety features, the system is unsafe when under PID control. PSMC, on the other hand, provides increased safety as well as good tracking.
Look-ahead Proposals for Robust Grid-based SLAM with Rao-Blackwellized Particle Filters
Authors: Grzonka Slawomir , Plagemann Christian , Grisetti Giorgio , Burgard Wolfram
Published: January 2009

Simultaneous Localization and Mapping (SLAM) is one of the classical problems in mobile robotics. The task is to build a map of the environment using on-board sensors while at the same time localizing the robot relative to this map. Rao-Blackwellized particle filters have emerged as a powerful technique for solving the SLAM problem in a wide variety of environments. It is a well-known fact for sampling-based approaches that the choice of the proposal distribution greatly influences robustness and efficiency achievable by the algorithm. In this paper, we present an improved proposal distribution for grid-based SLAM with Rao-Blackwellized particle filters, which utilizes whole sequences of sensor measurements rather than only the most recent one. We have implemented our system on a real robot and evaluated its performance on standard datasets as well as in hard outdoor settings with few and ambiguous features. Our approach improves the localization accuracy and the map quality, substantially reducing the risk of mapping failures.
Efficient Multi-robot Search for a Moving Target
Authors: Hollinger Geoffrey , Singh Sanjiv , Djugash Joseph , Kehagias Athanasios
Published: January 2009

This paper examines the problem of locating a mobile, non-adversarial target in an indoor environment using multiple robotic searchers. One way to formulate this problem is to assume a known environment and choose searcher paths most likely to intersect with the path taken by the target. We refer to this as the multi-robot efficient search path planning (MESPP) problem. Such path planning prob lems are NP-hard, and optimal solutions typically scale exponentially in the number of searchers. We present an approximation al gorithm that utilizes finite-horizon planning and implicit coordination to achieve linear scalability in the number of searchers. We prove that solving the MESPP problem requires maximizing a non-decreasing, submodular objective function, which leads to theoretical bounds on the performance of our approximation algorithm. We extend our analysis by considering the scenario where searchers are given noisy non-line-of-sight ranging measurements to the target. For this scenario, we derive and integrate online Bayesian measurement updating into our framework. We demonstrate the performance of our framework in two large-scale simulated environments, and we further validate our results using data from a novel ultra-wideband ranging sensor. Finally, we provide an analysis that demonstrates the relationship between MESPP and the intuitive average capture time metric. Results show that our proposed linearly scalable approximation algorithm generates searcher paths that are competitive with those generated by exponential algorithms.
A Robust Descriptor for Tracking Vertical Lines in Omnidirectional Images and Its Use in Mobile Robotics
Authors: Scaramuzza Davide , Siegwart Roland , Martinelli Agostino
Published: January 2009

In this paper we introduce a robust descriptor for matching vertical lines among two or more images from an omnidirectional camera. Furthermore, in order to make such a descriptor usable in the framework of indoor mobile robotics, this paper introduces a new simple strategy to extrinsically self-calibrate the omnidirectional sensor with the odometry reference system. In the first part of this paper we describe how to build the feature descriptor. We show that the descriptor is very distinctive and is invariant to rotation and slight changes in illumination. The robustness of the descriptor is validated through real experiments on a wheeled robot. The second part of the paper is devoted to the extrinsic self-calibration of the camera with the odometry reference system. We show that by implementing an extended Kalman filter that fuses the information from the visual features with the odometry, it is possible to extrinsically and automatically calibrate the camera while the robot is moving. In particular, it is theoretically shown that only one feature suffices to perform the calibration. Experimental results validate the theoretical contributions.
Fabrication and Analysis of Porous Shape Memory Polymer and Nanocomposites
Authors: Simkevitz S.L. , Naguib H.E.
Published: January 2009

The porous structure and shape memory effect (SME) were studied for a porous shape memory polymer (SMP) with varying densities, two different thicknesses and the addition of varying weight percentages of organoclay. In order to alter the density of the SMP, a batch processing technique was utilized in which the saturation pressure and foaming time were varied and saturation time and foaming temperature were kept constant. The change in density as the effect of reducing the thickness of the SMP on the time response of the SME was investigated. In addition, the effects of the change in density, change in thickness or the addition of organoclay on the recovery force of the SMP were elucidated. With the objective of designing an SMP to be used as an actuator, response time, recovery force and weight savings are critical parameters.
Water-borne Polyimides via Microwave-assisted Polymerization
Authors: Brunel Raphaël , Marestin Catherine , Martin Vincent , Mercier Régis
Published: January 2009

In the present study, the synthesis of high molecular weight polyimides was conducted in water using microwave irradiation. High molecular weight polymers were obtained after only 5 min of reaction time. The influence of different experimental parameters is discussed in connection with a thorough characterization of the synthesized polymers. From these polymers, self-supporting films were obtained.
Genetically modified food in the news: media representations of the GM debate in the UK
Authors: Augoustinos Martha , Crabb Shona , Shepherd Richard
Published: January 2009

This paper analyses a corpus of articles on GM crops and food which appeared in six UK newspapers in the first three months of 2004, the year following the GM Nation? debate (2003). Using the methods of critical discourse analysis we focus on how specific and pervasive representations of the major stakeholders in the national debate on GM—the British public, the British government, the science of GM, and biotechnology companies—served significant rhetorical functions in the controversy. Of particular significance was the pervasive representation of the British public as uniformly opposed to GM crops and food which served rhetorically to position the British government as undemocratic and as being beholden to powerful political and economic interests. Of significance also in our analysis, is how the science of GM farming itself became a highly contested arena. In short, our analysis demonstrates how the GM debate was represented in the newsprint media as a “battleground” of competing interests. We conclude by considering the possible implications of this representation given the increasing emphasis placed on the importance of deliberative and inclusive forms of science policy decision-making.
The Contribution of “Study Abroad” Programs to Japanese Internationalization
Authors: Asaoka Takako , Jun Yano
Published: January 2009

“Study abroad” needs promoting, as it is an effective alternative for many Japanese university students to enhance their international experience and cross-cultural understanding, thus contributing to the internationalization of Japanese universities. To consider what has to be done to promote “study abroad” programs, this research attempts to ascertain (a) the characteristics of the “study abroad” program of Japanese university students, (b) what Japanese university students think about the “study abroad” program, (c) the factors discouraging them from studying abroad, and (d) suggestions made by university staff to promote “study abroad” programs. Online survey results of 173 Japanese university students, interview answers and monthly reports of 20 Japanese university exchange students, opinions of 15 JAFSA members, and the JASSO symposium reports from 2005 to 2007 were used as data for this study. Suggestions are made to enable Japanese university staff to further promote “study abroad” programs among their students.
Mapping the Research Questions in Technical Communication
Authors: Rude Carolyn D.
Published: January 2009

Agreement about research questions can strengthen disciplinary identity and give direction to a field that is still maturing. The central research question this article poses foregrounds texts, broadly defined as verbal, visual, and multimedia, and the power of texts to mediate knowledge, values, and action in a variety of contexts. Related questions concern disciplinarity, pedagogy, practice, and social change. These questions overlap and inform each other. Any single study does not necessarily fall exclusively into one area. A mapping of a field's research questions is a political act, emphasizing some questions and marginalizing or excluding others. The emphases may change over time. This mapping illustrates reasons for the tensions between the academic and practitioner areas of the field. It also points out their shared research interests and opportunities for future research.
The Humanities and the Recovery of the Real World
Authors: Jacobs Jonathan
Published: January 2009

This article identifies a common intellectual project of the disciplines that constitute the Humanities. It does not define the humanities but characterizes some of the main features of the distinctive and essential kind of learning uniquely attainable by their study. The humanities enable us to attain an understanding of normativity in the broadest sense; humanistic study leads to a textured, penetrating comprehension of diverse valuative matters and concerns. Moreover, study in the humanities enables us to recognize and appreciate valuative realism . This is the view that valuative matters are appropriate objects of comprehension and that values are not simply projected in an expressivist or subjectivist manner. Valuative realism does not depend upon, and should not be assimilated into, knowledge that emulates the methods of the sciences. Humane studies develop a genuine understanding of diverse kinds of significance and educate people in the concepts and discourse to articulate it.
SoTL and National Difference
Authors: Brawley Sean , Kelly T. Mills , Timmins Geoff
Published: January 2009

What role does/should national difference play in our understanding of the scholarship of teaching and learning (SoTL) as a concept and a practice? Three historians from Australia, the UK and the USA muse on this important issue. Informed by their engagement with the literature and the field, they argue that national difference is an observable phenomenon within SoTL but that each national response has been shaped by the broader transnational/international engagements of recent years.
Visual Culture, Art History and the Humanities
Authors: Castañeda Iván
Published: January 2009

This essay will discuss the need for the humanities to address visual culture studies as part of its interdisciplinary mission in today's university. Although mostly unnoticed in recent debates in the humanities over historical and theoretical frameworks, the relatively new field of visual culture has emerged as a corrective to a growing disciplinary territorialism on the part of art history. A study of the theoretical purview of visual culture reveals that it in truth encompasses a continuation of art history's initial interdisciplinary humanist project of cultural critique initiated by Aby Warburg and Erwin Panofsky. This article will argue that art history's inability to fully appreciate visual culture's relevance in today's research and pedagogical settings has given the humanities the opportunity to address a field which is rooted in the humanities' project of interdisciplinary inquiry.
Effects of Work Experience, Patient Size, and Hand Preference on the Performance of Sonography Studies
Authors: Bastian Eric J. , Kits Joel K. , Weaver Joshua D. , Stevenson John R. , Carlton Lynn , Raaymakers Susan A. , Vanderpoel Jennifer
Published: January 2009

Reports to clinic managers of sonographer work-related musculoskeletal disorders, especially those linked to larger patient body sizes, are increasing annually. This study was conducted to determine if patient size, sonographer experience level, and hand preference affected image quality associated with ambidextrous scanning. Thirteen experienced and 11 novice sonographers performed right- and left-handed scans of target organs on three models (5th, 50th, and 95th percentile body weight). Estimated grip force was measured during each scan through the use of force matching with a digital dynamometer. Results revealed a significant ( P < .01) interaction effect between specialty and handedness for general and echocardiography for shoulder abduction angle; a significant difference among patient model sizes for grip forces, with the 95th percentile producing the highest estimated grip force values; and a significant difference in shoulder abduction angle among patient model sizes. Image quality was not different across specialties or handedness, and estimated grip force did not differ between handedness across specialties. These findings suggest that both inexperienced and experienced sonographers could benefit from ambidextrous abilities without increasing risk factors for injury or decreasing scanning quality for clinical practice.
Formation of Strands After Valve Replacement
Authors: Leung Nancy K.W.
Published: January 2009

Fibrin strands are long, thin, mildly echogenic and mobile structures that are usually incidental findings after prosthetic heart valve surgery. They are seen by transesophageal echocardiography in 6% to 45% of patients. The formation of these benign strands may be the result of cardiac manipulation by surgical instrumentation. A case study of strand formation after aortic valve replacement is detailed. In any valvular lesion, differential diagnoses include thrombus and vegetation, and thus the clinical picture is important in diagnosing and managing valvular lesions. Although strands rarely embolize and are not associated with poor prognosis, their management and significance are items of debate.
Uterine Perforation by an Intrauterine Contraceptive Device
Authors: Gasseling Michaela , Michael Kim
Published: January 2009

An intrauterine contraceptive device (IUCD) is an effective and widely accepted method of contraception. Although complications are uncommon, an IUCD can perforate the uterus, causing serious side effects. Sonography is often the first imaging modality used when uterine perforation is clinically suspected.
Use of Volume Imaging in the Evaluation of Intrauterine Contraceptive Devices
Authors: Wilson Michelle , Whyte-Evans Janice
Published: January 2009

Intrauterine contraceptive devices (IUD) have been a form of birth control for many hundreds of years. Just as their composition and architectures have changed, so have their sonographic appearances and clinical implications. With the emergence of volume imaging brings the ability to consistently evaluate the uterus in the coronal plane, which brings an entirely different diagnostic perspective and thought process for the evaluation of an IUD. This article provides three examples of how volume imaging is extending the sonographic evaluation of patients with IUDs.
Synthesis and characterisation of Ni-doped Fe3O4/polypyrrole magnetic and conducting nanocomposites with core–shell structure
Authors: Ma J. , Ji Y. , Shen X.
Published: January 2009

Electrical and magnetic function materials have many potential applications. A magnetic and conducting Ni-doped Fe3O4/polypyrrole (PPy) nanocomposite with a core–shell structure was prepared by in situ polymerisation of a pyrrole monomer in an aqueous solution containing a dispersion of Ni-doped Fe3O4 nanoparticles. The structure and properties of Ni-doped Fe3O4/PPy nanocomposites were characterised by X-ray diffraction (XRD), TEM, infrared spectrometry (IR), vibrating sample magnetometry (VSM) and thermogravimetry (TG). The results showed that the Ni-doped Fe3O4 nanoparticles were completely coated by polypyrrole; the resultant Ni-doped Fe3O4/PPy nanocomposites exhibited a good superparamagnetic behaviour and the saturation magnetisation was as high as 25·2 emu g−1 owing to the adoption of Ni-doped Fe3O4 as the magnetic source. In addition, the influences of Ni-doped Fe3O4 content on the electromagnetic properties of resultant nanocomposites were preliminarily investigated.
Microstructural chracterisation of Al–Si–xTi cast alloys
Authors: Zeren M. , Karakulak E.
Published: January 2009

The present paper reports the existence and morphology of intermetallic particles in Al–Si– xTi cast alloys. Near eutectic Al–Si alloys with 0, 0·1, 1, 2, and 5% Ti have been utilised for this purpose. Metallographic observations were made by the combination of an optical microscope and a scanning electron microscope. Wear tests were performed in a pin on disc tribometer under dry sliding conditions. The addition of Ti to the Al–Si alloys led to the precipitation of TiAlSi intermetallic phase. By increasing Ti content, hardness increases due to increasing volume fraction of relatively hard intermetallics.
Large-scale inference of the point mutational spectrum in human segmental duplications
Authors: Nakken Sigve , Rødland Einar A , Rognes Torbjørn , Hovig Eivind
Published: January 2009

Background

Recent segmental duplications are relatively large (≥ 1 kb) genomic regions of high sequence identity (≥ 90%). They cover approximately 4–5% of the human genome and play important roles in gene evolution and genomic disease. The DNA sequence differences between copies of a segmental duplication represent the result of various mutational events over time, since any two duplication copies originated from the same ancestral DNA sequence. Based on this fact, we have developed a computational scheme for inference of point mutational events in human segmental duplications, which we collectively term duplication-inferred mutations (DIMs). We have characterized these nucleotide substitutions by comparing them with high-quality SNPs from dbSNP, both in terms of sequence context and frequency of substitution types.

Results

Overall, DIMs show a lower ratio of transitions relative to transversions than SNPs, although this ratio approaches that of SNPs when considering DIMs within most recent duplications. Our findings indicate that DIMs and SNPs in general are caused by similar mutational mechanisms, with some deviances at the CpG dinucleotide. Furthermore, we discover a large number of reference SNPs that coincide with computationally inferred DIMs. The latter reflects how sequence variation in duplicated sequences can be misinterpreted as ordinary allelic variation.

Conclusion

In summary, we show how DNA sequence analysis of segmental duplications can provide a genome-wide mutational spectrum that mirrors recent genome evolution. The inferred set of nucleotide substitutions represents a valuable complement to SNPs for the analysis of genetic variation and point mutagenesis.
Delayed transfer of care from NHS secondary care to primary care in England: its determinants, effect on hospital bed days, prevalence of acute medical conditions and deaths during delay, in older adults aged 65 years and over
Authors: Jasinarachchi Krishantha H , Ibrahim Ibrahim R , Keegan Breffni C , Mathialagan Rajaratnam , McGourty John C , Phillips James RN , Myint Phyo K
Published: January 2009

Background

The delay in discharge or transfer of care back to the community following an acute admission to the hospital in older adults has long been a recognized challenge in the UK. We examined the determinants and outcomes of delayed transfer of care in older adults.

Methods

A prospective observational study was conducted in a district general hospital with a catchment population of 250,000 in England, UK. Those >= 65 years admitted to two care of the elderly wards during February 2007 were identified and prospectively followed-up till their discharge. Data was presented descriptively.

Results

36.7% (58/158) of patients had a delay in transfer of care. They tended to be older, had poorer pre-morbid mobility, and were more likely to be confused at the time of admission. Compared to the 2003 National Audit Report, a significantly higher percentage (29.3%vs.17%) awaited therapist assessments or (27.6%vs.9%) domiciliary care, with a lower percentage (< 1%vs.14%) awaiting further NHS care. Of 18 in-patient deaths, five occurred during the delay. Seven patients developed medical conditions during the delay making them unfit for discharge. The number of extra bed days attributable to delayed discharges in this study was 682 (mean = 4.8) days.

Conclusion

Awaiting therapy and domiciliary care input were significant contributing factors in delayed transfer of care. Similar local assessments could provide valuable information in identifying areas for improvement. Based on available current evidence, efficacy driven changes to the organisation and provision of support, for example rapid response delayed discharge services at the time of "fit to discharge" may help to improve the situation.
A genome-wide genetic signature of Jewish ancestry perfectly separates individuals with and without full Jewish ancestry in a large random sample of European Americans
Authors: Need Anna C , Kasperavičiūtė Dalia , Cirulli Elizabeth T , Goldstein David B
Published: January 2009

Background

It was recently shown that the genetic distinction between self-identified Ashkenazi Jewish and non-Jewish individuals is a prominent component of genome-wide patterns of genetic variation in European Americans. No study however has yet assessed how accurately self-identified (Ashkenazi) Jewish ancestry can be inferred from genomic information, nor whether the degree of Jewish ancestry can be inferred among individuals with fewer than four Jewish grandparents.

Results

Using a principal components analysis, we found that the individuals with full Jewish ancestry formed a clearly distinct cluster from those individuals with no Jewish ancestry. Using the position on the first principal component axis, every single individual with self-reported full Jewish ancestry had a higher score than any individual with no Jewish ancestry.

Conclusions

Here we show that within Americans of European ancestry there is a perfect genetic corollary of Jewish ancestry which, in principle, would permit near perfect genetic inference of Ashkenazi Jewish ancestry. In fact, even subjects with a single Jewish grandparent can be statistically distinguished from those without Jewish ancestry. We also found that subjects with Jewish ancestry were slightly more heterozygous than the subjects with no Jewish ancestry, suggesting that the genetic distinction between Jews and non-Jews may be more attributable to a Near-Eastern origin for Jewish populations than to population bottlenecks.
Crucial implication of protein kinase C (PKC)-δ, PKC-ζ, ERK-1/2, and p38 MAPK in migration of human asthmatic eosinophils
Authors: Langlois Anick , Chouinard Francois , Flamand Nicolas , Ferland Claudine , Rola-Pleszczynski Marek , Laviolette Michel
Published: January 2009

Asthma is associated with an eosinophil infiltration into the bronchial mucosa. 5-Oxo-6,8,11,14(E,Z,Z,Z)-eicosatetraenoic acid (5-oxo-ETE), a potent eosinophil chemotactic factor, activates cell motility, adherence, and proteolysis, notably, by promoting CD11b expression, matrix metalloproteinase (MMP)-9 secretion, and plasmin generation. We investigated the intracellular signaling pathways implicated in these various steps by using different, selective inhibitors. Human eosinophil migration through a reconstituted basement membrane in response to 5-oxo-ETE was greatly inhibited (≥72%) by the protein kinase C (PKC)-δ, PKC-ζ, ERK-1/2, and p38 inhibitors. Our findings indicate that PKC-δ mediates cell motility, CD11b expression, and MMP-9 granule release. PKC-ζ is also largely involved in eosinophil migration, although its specific targets remain undefined. ERK-1/2 and p38 modulate CD11b expression; ERK-1/2 is also involved in long-term MMP-9 secretion and p38 in the plasmin activation system. We demonstrated the crucial implication of PKC-δ, PKC-ζ, ERK-1/2, and p38 in human blood eosinophil migration through extracellular matrix components. Targeting specific pathways may have therapeutic potential for the treatment of allergic airway inflammation.
The mechanism involved in the repression of the μ opioid receptor gene expression in CEM ×174 cells infected by simian immunodeficiency virus
Authors: Liu Han , Li Hui , Guo Liyuan , Li Chaoying , Li Mengsen , Jiang Wei , Liu Xinhua , McNutt Michael A , Li Gang
Published: January 2009

Morphine can promote the pathogenesis of human acquired immunodeficiency syndrome through binding to the μ opioid receptor (MOR) in immune cells. Previous investigation has suggested that expression of the MOR gene in lymphocytes is triggered by cooperative interaction between transcription factors, specificity protein 1 (Sp1) and Ying Yang 1 (YY1), in the promoter region. However, the specific molecular mechanism by which immunodeficiency virus infection impacts regulation of the MOR gene expression in lymphocytes is still unclear. In this study, it was demonstrated that SIV (SIVmac239) infection may result in gradual reduction of the MOR gene expression and Sp1 during a period of 48 h postinfection by analysis of quantitative real-time RT-PCR and Western blotting. The results of methylation-specific PCR showed that two of 14 CpG islands adjacent to the Sp1 and YY1 elements in the promoter region were methylated, which together with reduced Sp1, contributed to the failure of interaction of Sp1 with YY1 and their binding to the elements, as determined by coimmunoprecipitation, chromatin immunoprecipitation-real-time PCR, and EMSAs. The repression of the MOR gene secondary to SIVmac239 infection could be abolished by the demethylating agent 5-aza-2′-deoxycytidine. Transfection with Sp1-expressing vector (PN3-Sp1) was also able to enhance the activity of the promoter in SIVmac239-infected cells. We therefore concluded that aberrant methylation of the promoter and reduction of Sp1 resulting from SIVmac239 infection led to the silencing of the MOR gene. This finding will be helpful in understanding the synergistic mechanism of HIV infection and morphine addiction in the pathogenesis of AIDS.
Impact of FcγRIIa-FcγRIIIa Polymorphisms and KRAS Mutations on the Clinical Outcome of Patients With Metastatic Colorectal Cancer Treated With Cetuximab Plus Irinotecan
Authors: Bibeau Frédéric , Lopez-Crapez Evelyne , Di Fiore Frédéric , Thezenas Simon , Ychou Marc , Blanchard France , Lamy Aude , Penault-Llorca Frédérique , Frébourg Thierry , Michel Pierre , Sabourin Jean-Christophe , Boissière-Michot Florence
Published: January 2009

Purpose

The antiepidermal growth factor receptor antibody cetuximab shows activity in irinotecan-refractory metastatic colorectal cancer (mCRC), mainly in wild-type KRAS tumors. Cetuximab may also exert antitumor effects through antibody-dependent cell-mediated cytotoxicity (ADCC) in which antibody Fc portion interacts with Fc receptors (FcγRs) expressed by immune cells. ADCC is influenced by FcγRIIa-H131R and FcγRIIIa-V158F polymorphisms that are clinically relevant in follicular lymphoma and metastatic breast cancer treated with rituximab and trastuzumab, respectively. We investigated the association of FcγR polymorphisms and KRAS mutation with the outcome of irinotecan-refractory mCRC patients treated with cetuximab plus irinotecan.

Patients and Methods

Tumor and normal tissues from 69 patients were screened for KRAS mutations using a sensitive multiplex assay and genotyped for FcγRIIa and FcγRIIIa polymorphisms by direct sequencing and multiplex allele-specific polymerase chain reaction, respectively. The results were correlated with response and progression-free survival (PFS).

Results

KRAS mutations were associated with lower response rate (4% v 27% in nonmutated patients; P = .021) and shorter PFS (3.0 v 5.3 months; P = .021). Patients with FcγRIIa-131H/H and/or FcγIIIa-158V/V genotypes had longer PFS than 131R and 158F carriers (5.5 v 3.0 months; P = .005). The difference remained significant for mutated-KRAS patients. By multivariate analysis, KRAS mutation and FcγR combined status were independent risk factors for PFS.

Conclusion

Combined FcγRIIa/FcγRIIIa polymorphisms are prognostic factors for disease progression in mCRC patients treated with cetuximab plus irinotecan. As these polymorphisms are also clinically relevant in mutated-KRAS mCRC, an important role of ADCC in cetuximab efficacy is presumed.
Evaluation of Screening Instruments for Cancer-Related Fatigue Syndrome in Breast Cancer Survivors
Authors: Alexander Susanna , Minton Ollie , Stone Patrick C.
Published: January 2009

Purpose

Cases of cancer-related fatigue syndrome (CRFS) can be reliably indentified using a diagnostic interview combined with a structured psychiatric interview. However, these interviews are time consuming to conduct, require specialist training, and are not suitable for routine clinical use. The purpose of this study was to identify whether a screening questionnaire could identify patients at high risk of clinically significant fatigue who should be considered for a suitable intervention.

Patients and Methods

The diagnostic interview for CRFS and the structured clinical interview for the diagnostic and statistical manual of mental disorders were used in order to identify breast cancer survivors who fulfilled the criteria for CRFS. Two fatigue questionnaires (the Bidimensional Fatigue Scale [BFS] and the Functional Assessment of Cancer Therapy-Fatigue subscale [FACT-F]) were administered in order to determine their screening properties.

Results

Two hundred women were interviewed and 60 women fulfilled the criteria for CRFS. The BFS cutoff score of 11 had a sensitivity of 92%, a specificity of 53%, a positive predictive value (PPV) of 46%, and a negative predictive value (NPV) of 94%. The FACT-F cutoff score of 36 had a sensitivity of 80%, a specificity of 71%, a PPV of 55%, and a NPV of 89%.

Conclusion

The BFS and FACT-F cutoff scores can be used to identify breast cancer survivors at higher risk of clinically significant ongoing post treatment fatigue. Neither scale can be used as a diagnostic instrument for CRFS.
Phase II Study of Capecitabine and Oxaliplatin for Advanced Adenocarcinoma of the Small Bowel and Ampulla of Vater
Authors: Overman Michael J. , Varadhachary Gauri R. , Kopetz Scott , Adinin Rosni , Lin E. , Morris Jeffrey S. , Eng Cathy , Abbruzzese James L. , Wolff Robert A.
Published: January 2009

Purpose

Adenocarcinomas of the small bowel and ampulla of Vater represent rare cancers that have limited data regarding first-line therapy. We conducted a phase II trial to evaluate the benefit of capecitabine in combination with oxaliplatin (CAPOX) in patients with advanced adenocarcinoma of small bowel or ampullary origin.

Patients and Methods

Eligible patients with metastatic or unresectable tumors and no prior systemic chemotherapy for advanced disease participated in this phase II trial. CAPOX was administered as a 21-day cycle with oxaliplatin 130 mg/m2 on day 1 and capecitabine 750 mg/m2 twice a day on days 1 through 14. The primary end point was overall response rate as assessed by Response Evaluation Criteria in Solid Tumors.

Results

Thirty-one patients were enrolled onto the study, and 30 patients received study treatment. The confirmed overall response rate was 50%; three patients with metastatic disease achieved complete responses. The median time to progression (TTP) was 11.3 months, and the median overall survival (OS) was 20.4 months. Subset analysis of patients with metastatic disease only (n = 25) revealed a median TTP of 9.4 months and median OS of 15.5 months. The most common grades 3 or 4 toxicities included fatigue (30%), peripheral neuropathy (10%), vomiting (10%), diarrhea (10%), and neutropenia (10%).

Conclusion

When administered to patients with good performance status, CAPOX is well tolerated and produces a superior response rate and longer OS compared with other regimens in the literature. CAPOX should be considered a new standard regimen for advanced small bowel and ampullary adenocarcinomas.
FGF ligands inDrosophilahave distinct activities required to support cell migration and differentiation
Authors: Kadam Snehalata , McMahon Amy , Tzou Phoebe , Stathopoulos Angelike
Published: January 2009

Fibroblast growth factor (FGF) signaling controls a vast array of biological processes including cell differentiation and migration, wound healing and malignancy. In vertebrates, FGF signaling is complex, with over 100 predicted FGF ligand-receptor combinations. Drosophila melanogaster presents a simpler model system in which to study FGF signaling, with only three ligands and two FGF receptors (FGFRs) identified. Here we analyze the specificity of FGFR [Heartless (Htl) and Breathless (Btl)]activation by each of the FGF ligands [Pyramus (Pyr), Thisbe (Ths) and Branchless (Bnl)] in Drosophila. We confirm that both Pyr and Ths can activate Htl, and that only Bnl can activate Btl. To examine the role of each ligand in supporting activation of the Htl FGFR, we utilize genetic approaches that focus on the earliest stages of embryonic development. When pyrand ths are equivalently expressed using the Gal4 system, these ligands support qualitatively different FGFR signaling responses. Both Pyr and Ths function in a non-autonomous fashion to support mesoderm spreading during gastrulation, but Pyr exhibits a longer functional range. pyr and ths single mutants exhibit defects in mesoderm spreading during gastrulation, yet only pyr mutants exhibit severe defects in dorsal mesoderm specification. We demonstrate that the Drosophila FGFs have different activities and that cell migration and differentiation have different ligand requirements. Furthermore, these FGF ligands are not regulated solely by differential expression, but the sequences of these linked genes have evolved to serve different functions. We contend that inherent properties of FGF ligands make them suitable to support specific FGF-dependent processes, and that FGF ligands are not always interchangeable.
An integrated model for prediction of thermo-mechanical behaviour of metal and work-rolls during hot strip rolling process
Authors: Farkoosh A R , Serajzadeh S
Published: January 2009

In this paper an integrated model has been developed that is capable of considering the effects of process parameters on the thermo-mechanical behaviour of the work-roll and the strip during hot rolling operations. The commercially finite element package ABAQUS is utilized to solve the governing equations, while an elasto-viscoplastic material behaviour is utilized in the model. The model may be employed in single-pass as well as multi-pass rolling layouts. Various aspects of the hot rolling process are predicted including temperature field and thermo-mechanical stresses within the work-roll as well as temperature, strain, and residual stresses distributions within the strip. To assess the accuracy of the model, predicted results have been compared with experimental data and good agreement has been observed.
Heuristic algorithms for re-entrant hybrid flow shop scheduling with unrelated parallel machines
Authors: Kim H-W , Lee D-H
Published: January 2009

This paper considers the scheduling problem in hybrid flow shops with parallel machines at each serial production stage. Each job may visit each stage several times, called the re-entrant flows. As an extension of the research on generic re-entrant hybrid flow shop scheduling, the unrelated parallel machines at each stage are considered and hence the processing time of a job at each stage depends on the machine where the job is processed. The problem is to determine the allocation of jobs to the unrelated parallel machines as well as the sequence of the jobs assigned to each machine for the bicriteria objectives of minimizing makespan and total tardiness. Since due dates must be satisfied after being negotiated with customers in most practical situations, the original problem is transformed into a problem with a single objective of minimizing makespan by moving the tardiness objective to a constraint set with a certain allowance. Because of the complexity of the problem, two heuristic algorithms are suggested and tested in this paper. In particular, the performances of the heuristics are shown with the gaps from the solution values obtained from a search heuristic with a sufficiently long computation time.
Technical Note—An Ambush Game with a Fat Infiltrator
Authors: Baston Vic , Kikuta Kensaku
Published: January 2009

This paper concerns a two-person zero-sum game between an infiltrator and a defender. The infiltrator wants to pass through a channel, while the defender wants to detect the infiltrator by laying static underwater devices across the channel. Previous work assumed the infiltrator has zero width. We consider an extension when the infiltrator has a positive width, and a proportion of its width needs to be detected by the underwater devices for a positive identification. We show that the positive-width problem reduces to the zero-width problem by an appropriate transformation.
A Computational Study of the Pseudoflow and Push-Relabel Algorithms for the Maximum Flow Problem
Authors: Chandran Bala G. , Hochbaum Dorit S.
Published: January 2009

We present the results of a computational investigation of the pseudoflow and push-relabel algorithms for the maximum flow and minimum s-t cut problems. The two algorithms were tested on several problem instances from the literature. Our results show that our implementation of the pseudoflow algorithm is faster than the best-known implementation of push-relabel on most of the problem instances within our computational study.
A graded response model for measuring person reliability
Authors: Ferrando Pere Joan
Published: January 2009

This paper extends Lumsden's fluctuation model to the graded response case and, from the resulting basic scaling model, develops a one‐dimensional item response theory graded response model (GRM). Under some additional assumptions, it follows that the item category response functions (ICRFs) can be closely approximated by the ICRFs of the standard GRM with equal item discrimination. For fixed item locations, the item responses depend on two individual differences parameters: the person central location and the person reliability. Procedures for estimating the person parameters and for addressing the goodness of fit of the proposed model as compared to the standard GRM are discussed. The accuracy of the person estimates is assessed by means of simulation studies. Finally, all the developments are illustrated using three empirical examples in personality measurement.
Symptoms of depression in non‐routine caregivers: The role of caregiver strain and burden
Authors: Phillips Anna C. , Gallagher Stephen , Hunt Kate , Der Geoff , Carroll Douglas
Published: January 2009

Objectives. The origins and persistence of psychological morbidity in caregivers are not fully understood. The present analysis examined the relationship between the strain and burden of caregiving and depression and anxiety in a large community sample. Social support and sleep quality were investigated as potential mediators.

Design. Cross‐sectional and prospective observational study.

Method. Individuals caring for someone other than their own child (N=393) were identified from a population of 2,079. Caregiving strain and burden, social support, and sleep quality were assessed. Participants completed the hospital anxiety and depression scale at the same time and 5 years later.

Results. Caregiving strain and burden were associated with depression and anxiety symptoms cross‐sectionally, and with a worsening of symptoms 5 years later. Sleep quality appeared to mediate the cross‐sectional relationships.

Conclusions. The demands of caregiving and associated sleep disruption contribute to symptoms of depression and anxiety in caregivers.
Electronic mail, a new written‐language register: A study with French‐speaking adolescents
Authors: Volckaert‐Legrier Olga , Bernicot Josie , Bert‐Erboul Alain
Published: January 2009

The aim of this study was to determine the extent to which the linguistic forms used by adolescents in electronic mail (e‐mail) differ from those used in standard written language. The study was conducted in French, a language with a deep orthography that has strict, addressee‐dependent rules for using second person personal pronouns (unfamiliar and familiar forms). Data were collected from 80 adolescents ages 12 to 15 in a natural situation where they had to introduce themselves by e‐mail to two addressees (peer/teacher). Participants were divided into two groups (skilled/unskilled in computer‐mediated communication). Their emails contained a large number of orthographic deviations (the most frequent being neographic forms). Participants skilled in computer‐mediated communication (CMC) deviated more than unskilled ones did. The number of orthographic deviations was not linked to the participants' standard writing ability. The personal‐pronoun data clearly showed that adolescents used the familiar form of ‘you’ (tu) to address the peer and the unfamiliar form (vous) to address the teacher. We conclude that, for adolescents, e‐mail constitutes a distinct written‐language register. Nevertheless, the e‐mail register seems to follow the pragmatic rules of standard spoken and written interaction.
TV as storyteller: How exposure to television narratives impacts at‐risk preschoolers' story knowledge and narrative skills
Authors: Linebarger Deborah L. , Piotrowski Jessica Taylor
Published: January 2009

Educational media serve as informal educators within the home by supplementing young children's development. Substantial evidence documents the contributions of educational television to preschoolers' acquisition of a variety of skills; however, television's natural capacity as storyteller and the role it plays in preschoolers' early literacy development has been largely overlooked. This study examined the effects of viewing different TV program types on 311 at‐risk preschoolers' story knowledge and narrative skills. Children were assigned to one of 4 viewing conditions (i.e. watching up to 40 episodes of a particular program type): no viewing; expository; embedded narrative; or traditional narrative. Story knowledge scores were higher for those viewing either narrative type. In contrast, viewing specific narrative types differentially affected the component skills of narrative competence. Story retelling and identification of explicit story events were higher after repeat viewing of embedded narratives while generating implicit story content was higher after repeat viewing of traditional narratives.