bluuebunny/crossref_metadata_2025 huggingface dataset:
Gene expression profiling of minimally differentiated acute myeloid leukemia: M0 is a distinct entity subdivided by RUNX1 mutation status
Authors: Silva Fernando P. G. , Swagemakers Sigrid M. A. , Erpelinck-Verschueren Claudia , Wouters Bas J. , Delwel Ruud , Vrieling Harry , van der Spek Peter , Valk Peter J. M. , Giphart-Gassler Micheline
Published: August 2009

Minimally differentiated acute myeloid leukemia (AML-M0) is defined by immature morphology and expression of early hematologic markers. By gene expression profiling (GEP) and subsequent unsupervised analysis of 35 AML-M0 samples and 253 previously reported AML cases, we demonstrate that AML-M0 cases express a unique signature that is largely separated from other molecular subtypes. Hematologic transcription regulators such as CEBPA, CEBPD, and ETV6, and the differentiation associated gene MPO appeared strongly down-regulated, in line with the primitive state of this leukemia. AML-M0 frequently carries loss-of-function RUNX1 mutation. Unsupervised analyses revealed a subdivision between AML-M0 cases with and without RUNX1 mutations. RUNX1 mutant AML-M0 samples showed a distinct up-regulation of B cell–related genes such as members of the B-cell receptor complex, transcription regulators RUNX3, ETS2, IRF8, or PRDM1, and major histocompatibility complex class II genes. Importantly, prediction with high accuracy of the AML-M0 subtype and prediction of patients carrying RUNX1 mutation within this subtype were possible based on the expression level of only a few transcripts. We propose that RUNX1 mutations in this AML subgroup cause lineage infidelity, leading to aberrant coexpression of myeloid and B-lymphoid genes. Furthermore, our results imply that AML-M0, although originally determined by morphology, constitutes a leukemia subgroup.
TET2 mutation is an independent favorable prognostic factor in myelodysplastic syndromes (MDSs)
Authors: Kosmider Olivier , Gelsi-Boyer Véronique , Cheok Meyling , Grabar Sophie , Della-Valle Véronique , Picard Françoise , Viguié Franck , Quesnel Bruno , Beyne-Rauzy Odile , Solary Eric , Vey Norbert , Hunault-Berger Mathilde , Fenaux Pierre , Mansat-De Mas Véronique , Delabesse Eric , Guardiola Philippe , Lacombe Catherine , Vainchenker William , Preudhomme Claude , Dreyfus François , Bernard Olivier A. , Birnbaum Daniel , Fontenay Michaëla ,   on behalf of the Groupe Francophone des Myélodysplasies
Published: August 2009

Oncogenic pathways underlying in the development of myelodysplastic syndromes (MDS) remain poorly characterized, but mutations of the ten-eleven translocation 2 (TET2) gene are frequently observed. In the present work, we evaluated the prognostic impact of TET2 mutations in MDS. Frameshift, nonsense, missense mutations, or defects in gene structure were identified in 22 (22.9%) of 96 patients (95% confidence interval [CI], 14.5-31.3 patients). Mutated and unmutated patients did not significantly differ in initial clinical or hematologic parameters. The 5-year OS was 76.9% (95% CI, 49.2%-91.3%) in mutated versus 18.3% (95% CI, 4.2%-41.1%) in unmutated patients (P = .005). The 3-year leukemia-free survival was 89.3% (95% CI, 63.1%-97.0%) in mutated versus 63.7% (95% CI, 48.2%-75.4%) in unmutated patients (P = .035). In univariate analysis (Cox proportional hazard model), the absence of TET2 mutation was associated with a 4.1-fold (95% CI, 1.4-12.0-fold) increased risk of death (P = .009). In multivariate analysis adjusted for age, International Prognostic Scoring System, and transfusion requirement, the presence of TET2 mutation remained an independent factor of favorable prognosis (hazard ratio, 5.2; 95% CI, 1.6-16.3; P = .005). These results indicate that TET2 mutations observed in approximately 20% of patients, irrespective of the World Health Organization or French-American-British subtype, represent a molecular marker for good prognosis in MDS.
Did genome duplication drive the origin of teleosts? A comparative study of diversification in ray-finned fishes
Authors: Santini Francesco , Harmon Luke J , Carnevale Giorgio , Alfaro Michael E
Published: August 2009

Background

One of the main explanations for the stunning diversity of teleost fishes (~29,000 species, nearly half of all vertebrates) is that a fish-specific whole-genome duplication event (FSGD) in the ancestor to teleosts triggered their subsequent radiation. However, one critical assumption of this hypothesis, that diversification rates in teleosts increased soon after the acquisition of a duplicated genome, has never been tested.

Results

Here we show that one of three major diversification rate shifts within ray-finned fishes occurred at the base of the teleost radiation, as predicted by the FSGD hypothesis. We also find evidence for two rate increases that are much younger than the inferred age of the FSGD: one in the common ancestor of most ostariophysan fishes, and a second one in the common ancestor of percomorphs. The biodiversity contained within these two clades accounts for more than 88% of living fish species.

Conclusion

Teleosts diversified explosively in their early history and this burst of diversification may have been caused by genome duplication. However, the FSGD itself may be responsible for a little over 10% of living teleost biodiversity. ~88% of species diversity is derived from two relatively recent radiations of freshwater and marine fishes where genome duplication is not suspected. Genome duplications are a common event on the tree of life and have been implicated in the diversification of major clades like flowering plants, vertebrates, and gnathostomes. However our results suggest that the causes of diversification in large clades are likely to be complex and not easily ascribed to a single event, even a dramatic one such as a whole genome duplication.
Cj0596 is a periplasmic peptidyl prolyl cis-trans isomerase involved in Campylobacter jejuni motility, invasion, and colonization
Authors: Rathbun Kimberly M , Hall Johanna E , Thompson Stuart A
Published: August 2009

Background

Campylobacter jejuni is a gastrointestinal pathogen of humans, but part of the normal flora of poultry, and therefore grows well at the respective body temperatures of 37°C and 42°C. Proteomic studies on temperature regulation in C. jejuni strain 81–176 revealed the upregulation at 37°C of Cj0596, a predicted periplasmic chaperone that is similar to proteins involved in outer membrane protein folding and virulence in other bacteria.

Results

The cj0596 gene was highly conserved in 24 strains and species of Campylobacter, implying the importance of this gene. To study the role that Cj0596 plays in C. jejuni pathogenesis, a mutant derivative of strain 81–176 was constructed in which the cj0596 gene was precisely deleted. A revertant of this mutant was isolated by restoring the gene to its original chromosomal location using streptomycin counterselection. The cj0596 mutant strain demonstrated a slightly decreased growth rate and lower final growth yield, yet was more motile and more invasive of human intestinal epithelial cells than wild-type. In either single or mixed infections, the mutant was less able to colonize mice than 81–176. The cj0596 mutant also expressed altered levels of several proteins.

Conclusion

Mutation of cj0596 has an effect on phenotypes related to C. jejuni pathogenesis, probably due to its role in the proper folding of critical outer membrane proteins.
The human immunodeficiency virus type 1 Vpr protein and its carboxy-terminally truncated form induce apoptosis in tumor cells
Authors: Nonaka Mizuho , Hashimoto Yoshie , Takeshima Shin-nosuke , Aida Yoko
Published: August 2009

The human immunodeficiency virus type 1 (HIV-1) accessory protein Vpr induces apoptosis after cell cycle arrest at the G2 phase in primate cells. We have reported previously that C81, a carboxy-terminally truncated form of Vpr, interferes with cell proliferation and results in apoptosis without G2 arrest. Here, we investigated whether this property of Vpr and C81 could be exploited for use as a potential anticancer agent. First, we demonstrated that C81 induced G1 arrest and apoptosis in all tumor cells tested. In contrast, Vpr resulted in G2 arrest and apoptosis in HeLa and 293 T cells. Vpr also suppressed the damaged-DNA-specific binding protein 1 (DDB1) in HepG2 cells, thereby inducing apoptosis without G2 arrest. G2 arrest was restored when DDB1 was overexpressed in cells that also expressed Vpr. Surprisingly, C81 induced G2 arrest when DDB1 was overexpressed in HepG2 cells, but not in HeLa or 293 T cells. Thus, the induction of Vpr- and C81-mediated cell cycle arrest appears to depend on the cell type, whereas apoptosis was observed in all tumor cells tested. Overall, Vpr and C81 have potential as novel therapeutic agents for treatment of cancer.
Reduction of lipoxidative load by secretory phospholipase A2 inhibition protects against neurovascular injury following experimental stroke in rat
Authors: Hoda Md Nasrul , Singh Inderjit , Singh Avtar K , Khan Mushfiquddin
Published: August 2009

Background

In animal models, ischemia reperfusion (IR) injury triggers membrane lipid degradation and accumulation of lipoxidative exacerbations in neurovascular unit, leading to blood brain barrier (BBB) damage and neurologic deficits. In this study, we investigated whether impeding membrane lipid breakdown by inhibiting secretory phospholipase A2 (sPLA2) activity reduces BBB leakage, leading to neuroprotection and functional recovery.

Methods

Focal cerebral IR injury was induced by middle cerebral artery occlusion (MCAO) in adult male rats. A sPLA2 inhibitor, 7,7-dimethyleicosadienoic acid (DEDA), was administered following IR injury. DEDA-treated animals were compared with vehicle-treated in terms of BBB leakage, edema, infarct volume, and neurological deficit. Membrane lipid degradation and the expression/activity of sPLA2 were also assessed. The role of one of the sPLA2 products, arachidonic acid (AA), on the morphology of the differentiated neuronal cell PC12 was examined by light microscopy.

Results

Treatment with DEDA after IR injury not only reduced BBB leakage but also decreased infarct volume and improved neurologic function. The treatment attenuated both the activity of sPLA2 and the levels of sPLA2-derived oxidized products. The metabolites of lipid oxidation/peroxidation, including the protein carbonyl, were reduced as well. The treatment also restored the levels of glutathione, indicating attenuation of oxidative stress. In vitrotreatment of PC12 cells with DEDA did not restore the AA-mediated inhibition of neurite formation and the levels of glutathione, indicating that effect of DEDA is up stream to AA release.

Conclusion

sPLA2-derived oxidative products contribute to significant neurovascular damage, and treatment with sPLA2 inhibitor DEDA ameliorates secondary injury by reducing exacerbations from lipoxidative stress.
Development of a RVFV ELISA that can distinguish infected from vaccinated animals
Authors: McElroy Anita K , Albariño César G , Nichol Stuart T
Published: August 2009

Background

Rift Valley Fever Virus is a pathogen of humans and livestock that causes significant morbidity and mortality throughout Africa and the Middle East. A vaccine that would protect animals from disease would be very beneficial to the human population because prevention of the amplification cycle in livestock would greatly reduce the risk of human infection by preventing livestock epizootics. A mutant virus, constructed through the use of reverse genetics, is protective in laboratory animal models and thus shows promise as a potential vaccine. However, the ability to distinguish infected from vaccinated animals is important for vaccine acceptance by national and international authorities, given regulations restricting movement and export of infected animals.

Results

In this study, we describe the development of a simple assay that can be used to distinguish naturally infected animals from ones that have been vaccinated with a mutant virus. We describe the cloning, expression and purification of two viral proteins, and the development of side by side ELISAs using the two viral proteins.

Conclusion

A side by side ELISA can be used to differentiate infected from vaccinated animals. This assay can be done without the use of biocontainment facilities and has potential for use in both human and animal populations.
Methamphetamine use and rates of incarceration among street-involved youth in a Canadian setting: a cross-sectional analysis
Authors: Milloy M-J , Kerr Thomas , Buxton Jane , Montaner Julio , Wood Evan
Published: August 2009

Background

Given concerns over rising use of methamphetamine, especially among street-involved youth, and the links between exposure to the correctional system and the production of drug-related harm, we sought to assess the relationship between ever using methamphetamine and reporting ever being incarcerated in the At-Risk Youth Survey (ARYS) in Vancouver, Canada.

Methods

The relationship between ever being imprisoned and ever using methamphetamine was estimated using a multivariate logistic regression analysis while also considering potentially confounding secondary demographic, social and behavioural variables.

Results

Of the 478 youth recruited into ARYS between September 2005 and October 2006, 385 (80.5%) reported ever being incarcerated overnight or longer. In the multivariate model, methamphetamine use was independently associated with ever being incarcerated (Adjusted Odds Ratio: 1.79, 95% Confidence Interval [CI]: 1.03 – 3.13).

Conclusion

Incarceration was very common in this cohort and strongly linked with ever using methamphetamine. This finding is of concern and, along with the previously identified risks of drug-related harm associated with incarceration, supports the development of novel public policy, such as community-based drug treatment, to address the use of methamphetamine among street youth.
PSGL-1-dependent myeloid leukocyte activation
Authors: Zarbock Alexander , Müller Helena , Kuwano Yoshihiro , Ley Klaus
Published: August 2009

Review on PSGL-1 effects on signaling in myeloid leukocytes activates following selectin engagement.

Cell-cell interactions mediating leukocyte recruitment and inflammation are crucial for host defense. Leukocyte recruitment into injured tissue proceeds in a multistep process. The first contact of leukocytes with endothelial cells (“capturing” or “tethering”) is mediated by selectins and their counter-receptor P-selectin glyco-protein ligand (PSGL)-1. During capture and rolling, leukocytes collect different inflammatory signals, which can activate various pathways. Integration of these signals leads to leukocyte activation, integrin-mediated arrest, cytoskeleton rearrangement, polarization, and transmigration. PSGL-1 on leukocytes also binds to activated platelets, where P-selectin is expressed at locally high site densities following α-granule fusion with the plasma membrane. Here, we review the signaling functions of PSGL-1 and speculate how the different known signaling events might relate to different phases of leukocyte recruitment.
A chromatin insulator mediates transgene homing and very long-range enhancer-promoter communication
Authors: Fujioka Miki , Wu Xian , Jaynes James B.
Published: August 2009

Insulator sequences help to organize the genome into discrete functional regions by preventing inappropriate cross-regulation. This is thought to be mediated in part through associations with other insulators located elsewhere in the genome. Enhancers that normally drive Drosophila even skipped(eve) expression are located closer to the TER94transcription start site than to that of eve. We discovered that the region between these genes has enhancer-blocking activity, and that this insulator region also mediates homing of P-element transgenes to the eve-TER94 genomic neighborhood. Localization of these activities to within 0.6 kb failed to separate them. Importantly, homed transgenic promoters respond to endogenous eve enhancers from great distances, and this long-range communication depends on the homing/insulator region, which we call Homie. We also find that the eve promoter contributes to long-distance communication. However, even the basal hsp70 promoter can communicate with eve enhancers across distances of several megabases, when the communication is mediated by Homie. These studies show that, while Homie blocks enhancer-promoter communication at short range, it facilitates long-range communication between distant genomic regions, possibly by organizing a large chromosomal loop between endogenous and transgenic Homies.
The gender imbalance in academic medicine: a study of female authorship in the United Kingdom
Authors: Sidhu Reena , Rajashekhar Praveen , Lavin Victoria L , Parry Joanne , Attwood James , Holdcroft Anita , Sanders David S
Published: August 2009

Summary

Objectives

A shortfall exists of female doctors in senior academic posts in the United Kingdom. Career progression depends on measures of esteem, including publication in prestigious journals. This study investigates gender differences in first and senior authorship in six peer-reviewed British journals and factors that are associated with publication rates.

Design and main outcome measures

Data was collected on United Kingdom first and senior authors who had published in the British Medical Journal, Lancet, British Journal of Surgery, Gut, British Journal of Obstetrics and Gynaecology and the Archives of Diseases in Childhood. Authorship and gender were quantified for 1970, 1980, 1990, 2000 and 2004 ( n=6457). In addition, selected questions from the Athena Survey of Science Engineering and Technology (ASSET2006), web-based doctor's self-report of publications were also analysed ( n=1162).

Results

Female first authors increased from 10.5% in 1970 to 36.5% in 2004 (p<0.001) while female senior authors only increased from 12.3% to 16.5% (p=0.046). Within individual journals, the largest rise was in British Journal of Obstetric and Gynaecology with 4.5- and 3-fold increases for first and senior authors, respectively. In contrast, female senior authors marginally declined in Gut and Lancet by 2.8% and 2.2%, respectively. ASSET2006 identified that female respondents who were parents were less likely to have publications as sole (p=0.02) and joint authors (p<0.001) compared to male respondents. Female respondents with care responsibilities for parents/partner also had less publications as lead authors compared to those without carer responsibilities (p<0.001).

Conclusion

The increase in UK female first authors is encouraging. In contrast, there is considerable lag and in some specialties a decline in female senior authors. Factors that could narrow the gender gap in authorship should be sought and addressed.
Knowledge mobilisation builds local research collaborations for social innovation
Authors: Phipps David J. , Shapson Stan
Published: August 2009

Universities seek to maximise the impact of their research by investing in technology commercialisation services but universities fail to support the various impacts of non-commercial research. This paper describes the experience of York University (Toronto, Canada) in developing the institutional capacity to support knowledge mobilisation to maximise the impacts of research from the social sciences and humanities. York works in partnership with local research users to provide enhanced access to research through dedicated support for research collaborations. Grounded in theories of knowledge transfer and exchange, and illustrated with examples, this paper demonstrates how investments in knowledge mobilisation create value for the institution, researchers, graduate students and research partners.
Including economic perspectives and evidence in Campbell reviews to inform policy and practice: a critical review of current approaches
Authors: Shemilt Ian , Mugford Miranda
Published: August 2009

This paper evaluates current approaches to incorporating economic perspectives and evidence into systematic reviews, using 31 of the 33 reviews completed under the editorial control of The Campbell Collaboration. Of these, 74% incorporated economic perspectives, and 26% attempted to incorporate economic evidence by collecting and summarising data on resource use, costs and/or cost-effectiveness from primary studies. We conclude that while most Campbell reviews incorporate an economic dimension that is of potential utility to end users, the scope and quality of current approaches is limited.
The construction of maintenance treatment legitimacy: a discourse analysis of a policy shift
Authors: Ekendahl Mats
Published: August 2009

Opiate addict maintenance treatment (MT) has been controversial in Sweden. In 2004, however, a public authority conducted a review of MT research that paved the way for a relatively less restrictive policy. The present study examines how scientific evidence was constructed in the preparation of this policy shift. Written commentaries (by authorities, organisations etc) on a preliminary version of the review were analysed by use of discourse theory. The results suggest that the final review contains elements of three competing discourses and elucidate how a particular MT regime was made to appear objectively as the only viable solution for dealing with opiate addicts.
Knowledge brokering: the missing link in the evidence to action chain?
Authors: Ward Vicky , House Allan , Hamer Susan
Published: August 2009

Transferring healthcare research into policy and practice is a messy and complex process that both policy makers and researchers can struggle with. A potential solution is to use individuals or organisations as knowledge brokers. Using a range of literature, this paper explains the theory behind knowledge brokering, identifies three models of brokering and explores the challenges of brokering. We suggest that clarifying these factors is a significant step towards planning well-designed and rigorously evaluated brokering interventions. We also suggest that a clearly defined theoretical framework could help us to find out more about how brokering works and its effectiveness.
What do practitioners want from research, what do funders fund and what needs to be done to know more about what works in the new world of children’s services?
Authors: Stevens Madeleine , Liabo Kristin , Witherspoon Sharon , Roberts Helen
Published: August 2009

This paper is intended as a contribution to the debate on the place of research in children’s services from a funder of social research and three researchers, two of whom spent (between them) 12 years in an organisation delivering services to children and young people. We draw on two studies, the first identifying the questions to which practitioners in social care wanted answers; the second describing the degree of ‘fit’ between funded research and practitioners’ questions. These inform a discussion of the kinds of research and research infrastructure needed to support high-quality social care services for children.
Using ‘systems awareness’: a proposed mechanism for monitoring communications
Authors: Grebmer Klaus von , Hovland Ingeborg
Published: August 2009

Communication is an integral part of policy research, yet the impact of the communications process is difficult to monitor and evaluate. This paper reflects on one possible approach to monitoring communications, taking as its starting point ‘systems awareness’, or the awareness that communication efforts are situated within organisational, informational, social and political systems. Possible elements of a monitoring mechanism that takes these systems into account are proposed, and a brief example from the International Food Policy Research Institute (IFPRI) is included.
Interactive Modeling for Ongoing Utility of Pharmacogenetic Diagnostic Testing: Application for Warfarin Therapy
Authors: Linder Mark W , Bon Homme Marjorie , Reynolds Kristen K , Gage Brian F , Eby Charles , Silvestrov Natalia , Valdes Roland
Published: August 2009

Background: The application of pharmacogenetic results requires demonstrable correlations between a test result and an indicated specific course of action. We developed a computational decision-support tool that combines patient-specific genotype and phenotype information to provide strategic dosage guidance. This tool, through estimating quantitative and temporal parameters associated with the metabolism- and concentration-dependent response to warfarin, provides the necessary patient-specific context for interpreting international normalized ratio (INR) measurements.

Methods: We analyzed clinical information, plasma S-warfarin concentration, and CYP2C9 (cytochrome P450, family 2, subfamily C, polypeptide 9) and VKORC1 (vitamin K epoxide reductase complex, subunit 1) genotypes for 137 patients with stable INRs. Plasma S-warfarin concentrations were evaluated by VKORC1 genotype (−1639G>A). The steady-state plasma S-warfarin concentration was calculated with CYP2C9 genotype–based clearance rates and compared with actual measurements.

Results: The plasma S-warfarin concentration required to yield the target INR response is significantly (P < 0.05) associated with VKORC1 −1639G>A genotype (GG, 0.68 mg/L; AG, 0.48 mg/L; AA, 0.27 mg/L). Modeling of the plasma S-warfarin concentration according to CYP2C9 genotype predicted 58% of the variation in measured S-warfarin concentration: Measured [S-warfarin] = 0.67(Estimated [S-warfarin]) + 0.16 mg/L.

Conclusions: The target interval of plasma S-warfarin concentration required to yield a therapeutic INR can be predicted from the VKORC1 genotype (pharmacodynamics), and the progressive changes in S-warfarin concentration after repeated daily dosing can be predicted from the CYP2C9 genotype (pharmacokinetics). Combining the application of multivariate equations for estimating the maintenance dose with genotype-guided pharmacokinetics/pharmacodynamics modeling provides a powerful tool for maximizing the value of CYP2C9 and VKORC1 test results for ongoing application to patient care.
Experiments in TurkishGerman film-making: Aye Polat, Kutlu Ataman, Neco elik, Aysun Bademsoy and Kanak Attak
Authors: Halle Randall
Published: August 2009

Although narrative entertainment film is the dominant mode of representation for portrayals of the experience of migration, this essay focuses on the works of film-makers who have worked in an experimental mode: Aye Polat, Neco elik, Kutlu Ataman, the Kanak-TV productions and Aysun
Bademsoy. These film-makers produce work largely out of the experience of migration between Germany and Turkey. They incorporate lyrical poetic styles, explore expanded cinematic and installation work, undertake engage interventionist projects and provide new documents of vibrant cultural
complexity.
Silenced memories: notes on remembering in new Turkish cinema
Authors: Suner Asuman
Published: August 2009

This article aims to discuss different modes of remembering in new wave Turkish cinema with a specific focus on the question of the representation of non-Muslim minorities in Turkey. It argues that in new popular films, questions of history and politics are often downplayed and the past is remembered merely in a nostalgic mode, whereas in new political films, subjective remembrance of the past is strongly interconnected with questions of history and politics. To this end, it examines two recent films as examples to the categories of new popular cinema and new political cinema: Serdar Akar'sDar Alanda Ksa Paslamalar/Offside(2000) and Yeim Ustaolu'sBulutlar Beklerken/Waiting for the Clouds(2003). Despite their differences,Offside and Waiting for the Cloudsshare a new perspective on the question of Turkey's traumatic past with regard to its non-Muslim minorities. Both films resonate with a sense of loss and a concomitant silence. Instead of offering an unequivocal picture of the past, both films direct attention to absences, gaps and silences in the stories. Finally, offering subjective memory accounts, they both provide alternative narratives to official historiography and nationalist discourses.
Evaluation of a Proposed Space and Missile Warning Symbology Standard for Graphical Displays
Authors: Blackwell Janet S. , Cuomo Donna L.
Published: August 2009

A discriminability evaluation was performed on a proposed Space and Missile Warning symbol set. Our analysis focused on the discriminability of the symbols and the application of the information coding techniques. Inconsistent or inappropriate use of coding techniques can affect a user's interpretation of the symbol's intended meaning. Potential problems included the similarity of individual symbols, use of alphanumeric markers and partially shaded symbols, and the lack of guidance on the minimum size of the symbols. After a lengthy review of previous research, we felt the literature could not provide adequate solutions. A two-part discriminability study was conducted to test the overall effects of the information coding techniques on discriminability, to identify individual symbols with low discriminability, and to determine an appropriate minimum size for these symbols. Search time was used as a measure of symbol discriminability. Size, shape, markers, and shading had significant effects on search time and errors. The experiments confirmed the suspected discriminability problems and modifications were made to the existing symbol set to create three new alternative symbol sets. Testing performed on these new symbol sets revealed that many of the problem areas from the original symbol set had been improved. Design guidelines and a new modified symbol set were proposed for review by the operational community.
The Effect of Roll-Stabilized Sensor Information on Pilot Performance
Authors: Montazer M. Ali , Ferranti Michael J.
Published: August 2009

A study of the night vision sensor systems on helicopters was conducted at the flight simulation facilities at Sikorsky Aircraft. The study was concerned with determining possible pilot performance improvements with the sensor system being roll-stabilized with respect to the airframe as opposed to it being non-roll-stabilized. A six-pilot × two-sensor factorial experiment was designed and data were collected with respect to nine response variables. The results of the statistical analysis performed on the data were mixed in terms of the superiority of one sensor design over the other. The power collective input was significantly greater for the roll-stabilized design. However, the pilots also flew faster and made fewer errors, though the differences were not significant. One reason for such results might be that the pilots were less familiar with the roll-stabilized design, as it is a more recent technology.
Errors in Aviation Maintenance: Taxonomy and Control
Authors: Drury Colin G.
Published: August 2009

Maintenance errors account for a small, but highly visible, portion of aviation-related accidents and fatalities. To measure, and hence eventually control, errors in any field requires a taxonomy which enumerates and classifies the errors. This taxonomy can come from reported errors, but a pro-active system is needed to cover potential errors, as well as those which happen to have been committed and recorded so far. A standard starting point for human and system errors is the description and analysis of those tasks necessary to complete the maintenance-inspection requirements of aircraft in an approved manner. As each step of this Task Description is listed, the failure modes associated with that step can be logically deduced. Following an extensive Task Description and Analysis of aircraft maintenance, an error taxonomy was developed from the failure modes of each task. From current theoretical approaches to human error come ways of extending this classification, and of relating potential errors to levels of human functioning within the system.
Tailoring the Pilot's Associate to Match Pilot Preferences
Authors: Judge Carol Lynn A. , Smith Richard A. , Beaudet Carl A.
Published: August 2009

The research described in this paper documents the creation, development, implementation, and initial evaluation of a prototype intelligent system tailoring tool called the Mission Support Tool (MST). The MST is a ground-based, pre-mission interface between the fighter pilot, a larger global mission planning system and the electronic crew-member or Pilot's Associate (PA). The primary function of the MST is to furnish pilots with a means for tailoring the PA to their individual preferences for air-to-air combat missions. The MST helps the PA operate in a predictable manner by allowing the pilot to preselect, weigh, and tailor plans to be proposed to the pilot by the PA prior to the mission, which domain experts agree will pay high dividends in pilot acceptance, trust, and human-electronic crew-member teamwork.
Ongoing and Planned R&D Efforts in Airway Facilities Maintenance
Authors: Gardner-Bonneau Daryle Jean , Wiley John L.
Published: August 2009

Airway facilities maintenance has been a neglected area of human factors R&D until recently. The National Plan for Aviation Human Factors, however, specifically mandates that the needs of aircraft and airway facility maintainers, as well as pilots and controllers, be addressed in the design and operation of new systems. The purpose of this paper is to outline the major research issues within the area of airway facilities maintenance, and to describe some of the Federal Aviation Administration's ongoing efforts to address these issues.
Effects of Error-Proofing and Chemical/Biological/Radiation Protective Glove use on Touch Panel Operation
Authors: Beringer Dennis B.
Published: August 2009

Previous studies suggested that initial-contact error rates were higher for touch input devices (resistive and infrared) than for various hardware keys. A follow-up study was conducted to evaluate the effects of chemical/biological/radiation (CBR) protective gloves on performance. Error data from this and the preceding study in this series were somewhat misleading due to differences in the input sampling strategies between hardware keys and touch panels. The initially high error rates for the resistive panel (21.6% using flight gloves and a 26.1% using CBR gloves) were considered unrepresentative of a true operating environment because nonkey contacts would be ignored by the system. Revision of the input-sensing logic produced 100% accuracy for the resistive panel in the replication study. However, multiple contacts were required in 5% (median of 4.1%) of the trials. Overall, 4% required only a second contact for correct activation of the designated key while 3- and 4-contact activations amounted to 0.6% of all trials. Conclusions drawn from the research were that CBR gloves do not significantly degrade performance over standard flight gloves or, for that matter, over the bare hand (errors or response times) and that the occurrence of multiple touches is small and virtually disappears with experience and adequate feedback, errors usually occurring in early trials and in no-feedback conditions. Thus, systems using gloved operators are unlikely to experience serious performance degradation if adequate key sizes for bare-handed activation are used and if timely and relevant feedback is provided to the operator.
The Effects of Head and Sensor Movement on Flight Profiles during Simulated Dive Bombing
Authors: Wells Maxwell J. , Osgood Robert K.
Published: August 2009

A dive bombing mission was performed in a simulator by 5 experienced USAF pilots. Their view out of the cockpit was provided by an aircraft-fixed or head-steered sensor. Despite significant differences in performance with the two sensors, the mean flight profiles flown with each sensor were similar. However, with the head-steered sensor, some subjects made consistently different head movements. The same subjects also flew different flight profiles. These subjects exploited the mobility of the head-steered sensor to make large amplitude head displacements during ascent. As a result, they sighted the target earlier. It is shown that these early-sighting subjects made changes to their flight profiles during ascent which allowed them, during descent, to aim their aircraft at the target earlier, while higher. Consequently, the early-sighting subjects released their bombs significantly higher than the late-sighting subjects (high bomb release is beneficial to aircraft survival).
Second Liquid – an Intermediate Phase of Sublimation
Authors: Mosienko B. A.
Published: August 2009

According to current concepts there is only one mechanism of intermolecular interaction (Van der Waals forces). The question arises: Why does liquid exist? The search for answer to this question leads to the assumption that there are two mutually independent mechanisms of intermolecular interaction. This assumption, taken as an initial postulate, provides the possibility of existence of some other modification of liquid which is totally different from ordinary liquid by its physical properties. It has been proposed that it is precisely this modification (second liquid) that is the intermediate state of matter in the sublimation process. The arguments in favor of this hypothesis are adduced. Specifically, the existence of two modifications of liquid helium might be considered a serious empirical argument; in the view of proposed approach, superfluid helium II is the second liquid of helium in the bulk phase.
Effect of combination therapy with thyroxine (T4) and 3,5,3′-triiodothyronine versus T4 monotherapy in patients with hypothyroidism, a double-blind, randomised cross-over study
Authors: Nygaard Birte , Jensen Ebbe Winther , Kvetny Jan , Jarløv Anne , Faber Jens
Published: August 2009

Background

Treatment of hypothyroidism with 3,5,3′-triiodothyronine (T3) is controversial. A recent meta-analysis concludes that no evidence is present in favour of using T3. However, the analysis included a mixture of different patient groups and dose-regimens.

Objective

To compare the effect of combination therapy with thyroxine (T4) and T3 versus T4 monotherapy in patients with hypothyroidism on stable T4 substitution.

Study design

Double-blind, randomised cross-over. Fifty micrograms of the usual T4 dose was replaced with either 20 μg T3 or 50 μg T4 for 12 weeks, followed by cross-over for another 12 weeks. The T4 dose was regulated if needed, intending unaltered serum TSH levels.

Evaluation

Tests for quality of life (QOL) and depression (SF-36, Beck Depression Inventory, and SCL-90-R) at baseline and after both treatment periods.

Inclusion criteria

Serum TSH between 0.1 and 5.0 mU/l on unaltered T4 substitution for 6 months.

Results

A total of 59 patients (55 women); median age 46 years. When comparing scores of QOL and depression on T4 monotherapy versus T4/T3 combination therapy, significant differences were seen in 7 out of 11 scores, indicating a positive effect related to the combination therapy. Forty-nine percent preferred the combination and 15% monotherapy (P=0.002). Serum TSH remained unaltered between the groups as intended.

Conclusion

In a study design, where morning TSH levels were unaltered between groups combination therapy, (treated with T3 20 μg once daily) was superior to monotherapy by evaluating several QOL, depression and anxiety rating scales as well as patients own preference.
Elastosonographic evaluation of thyroid nodules in acromegaly
Authors: Scacchi Massimo , Andrioli Massimiliano , Carzaniga Chiara , Vitale Giovanni , Moro Mirella , Poggi Luca , Pecori Giraldi Francesca , Fatti Letizia M , Cavagnini Francesco
Published: August 2009

Objective

Ultrasound-elastography (US-E) appears to be a helpful tool for the diagnosis of thyroid cancer. In acromegaly, the prevalence of thyroid cancer is still debated. The aims of this study were to evaluate thyroid nodules in acromegaly and to establish the accuracy of US-E in providing information on their nature, using cytological analysis as a reference.

Subjects and methods

US-E was applied to 90 nodules detected in 25 acromegalic patients and to 94 nodules found in 31 non-acromegalic goitrous subjects. The lesions were classified according to the elasticity scores (ES) as soft (ES 1–2) or hard (ES 3–4). Fine needle aspiration cytology could be performed in 60.8% of hard nodules in acromegalics and in 86.7% of hard nodules in controls.

Results

The prevalence of hard nodules was significantly higher in the whole group of acromegalic patients than in controls (56.8 vs 16.0%, P<0.0001). The prevalence of hard nodules in patients with active acromegaly (68.9%) was greater, though not to a statistically significant extent, than that observed in cured (44.4%) and controlled (52.5%) patients. Cytology revealed malignancy or suspect malignancy in four of the nodules of non-acromegalic subjects and in none of the nodules of acromegalic patients.

Conclusions

This study has demonstrated a high prevalence of stiff thyroid nodules in acromegaly, greater than that found in non-acromegalic goitrous subjects. In acromegalics, hard nodules appeared not to be malignant on cytopathological examination and are probably of fibrous nature. Thus, US-E appears to be of limited value for the diagnosis of thyroid cancer in acromegaly.
The increments of a bifractional Brownian motion
Authors: El-Nouty Charles
Published: August 2009

Let {BH;K(t),t≧ 0} be a bifractional Brownian motion with indexes 0 <H< 1 and 0 <K≦ 1 and define the statistic\documentclass{aastex} \usepackage{amsbsy} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{bm} \usepackage{mathrsfs} \usepackage{pifont} \usepackage{stmaryrd} \usepackage{textcomp} \usepackage{upgreek} \usepackage{portland,xspace} \usepackage{amsmath,amsxtra} \usepackage{bbm} \pagestyle{empty} \DeclareMathSizes{10}{9}{7}{6} \begin{document} $$V_T = \mathop {\sup }\limits_{0 \leqq s \leqq T - a_T } \beta _T \left| {B_{H,K} (s + a_T ) - B_{H,K} (s)} \right|$$ \end{document}whereβTandαTare suitably chosen functions ofT≧ 0. We establish some laws of the iterated logarithm forVT.
Polar cremona transformations and monodromy of polynomials
Authors: Ahmed Imran
Published: August 2009

Consider the gradient map associated to any non-constant homogeneous polynomial
f
∈ ℂ[
x0
, ...,
xn
] of degree
d
, defined by \documentclass{aastex}
\usepackage{amsbsy}
\usepackage{amsfonts}
\usepackage{amssymb}
\usepackage{bm}
\usepackage{mathrsfs}
\usepackage{pifont}
\usepackage{stmaryrd}
\usepackage{textcomp}
\usepackage{upgreek}
\usepackage{portland,xspace}
\usepackage{amsmath,amsxtra}
\usepackage{bbm}
\pagestyle{empty}
\DeclareMathSizes{10}{9}{7}{6}
\begin{document}
$$\varphi _f = grad (f):D(f) \to \mathbb{P}^n ,(x_0 : \ldots :x_n ) \to (f_0 (x): \ldots :f_n (x))$$
\end{document} where
D
(
f
) = {
x
∈ ℙ
n
;
f
(
x
) ≠ 0} is the principal open set associated to
f
and
fi
=
∂f
/
∂xi
. This map corresponds to polar Cremona transformations. In Proposition 3.4 we give a new lower bound for the degree
d
(
f
) of ϕ
f
under the assumption that the projective hypersurface
V
:
f
= 0 has only isolated singularities. When
d
(
f
) = 1, Theorem 4.2 yields very strong conditions on the singularities of
V
.
Broughton polynomials and characteristic varieties
Authors: Raza Zahid
Published: August 2009

We introduce a family of polynomials in two variables, generalizing the Broughton polynomial and giving interesting examples of characteristic varieties with many translated components.
Weighted approximation via Θ-summations of Fourier-Jacobi series
Authors: Chripkó Ágnes
Published: August 2009

This paper is devoted to the study of Θ-summability of Fourier-Jacobi series. We shall construct such processes (using summations) that are uniformly convergent in a Banach space (\documentclass{aastex}
\usepackage{amsbsy}
\usepackage{amsfonts}
\usepackage{amssymb}
\usepackage{bm}
\usepackage{mathrsfs}
\usepackage{pifont}
\usepackage{stmaryrd}
\usepackage{textcomp}
\usepackage{upgreek}
\usepackage{portland,xspace}
\usepackage{amsmath,amsxtra}
\usepackage{bbm}
\pagestyle{empty}
\DeclareMathSizes{10}{9}{7}{6}
\begin{document}
$$C_{w_{\gamma ,\delta } } ,\parallel \cdot \parallel _{w_{\gamma ,\delta } }$$
\end{document}) of continuous functions. Some special cases are also considered, such as the Fejér, de la Vallée Poussin, Cesàro, Riesz and Rogosinski summations. Our aim is to give such conditions with respect to Jacobi weights
wγ,δ
,
wα,β
and to summation matrix Θ for which the uniform convergence holds for all
f
∈ \documentclass{aastex}
\usepackage{amsbsy}
\usepackage{amsfonts}
\usepackage{amssymb}
\usepackage{bm}
\usepackage{mathrsfs}
\usepackage{pifont}
\usepackage{stmaryrd}
\usepackage{textcomp}
\usepackage{upgreek}
\usepackage{portland,xspace}
\usepackage{amsmath,amsxtra}
\usepackage{bbm}
\pagestyle{empty}
\DeclareMathSizes{10}{9}{7}{6}
\begin{document}
$$C_{w_{\gamma ,\delta } }$$
\end{document}. Order of convergence will also be investigated. The results and the methods are analogues to the discrete case (see [16] and [17]).
On strictly weak mixing C *-dynamical systems and a weighted ergodic theorem
Authors: Mukhamedov Farrukh
Published: August 2009

We prove that unique ergodicity of tensor product of a
C
*-dynamical system implies its strictly weak mixing. By means of this result a uniform weighted ergodic theorem with respect to
S
-Besicovitch sequences for strictly weak mixing dynamical systems is proved. Moreover, we provide certain examples of strictly weak mixing dynamical systems.
Turán type inequalities for some probability density functions
Authors: Baricz Árpád
Published: August 2009

In this paper we present some Turán type inequalities for the probability density function (pdf) of the non-central chi-squared distribution, non-central chi distribution and Student distribution, respectively. Moreover, we improve a result of Laforgia and Natalini concerning a Turán type inequality for the modified Bessel functions of the second kind.
On the Dirichlet problem with nonconvex nonlinearity
Authors: Galewski Marek
Published: August 2009

We provide existence results for 2
m
order Dirichlet problems with nonconvex nonlinearity which satisfies general local growth conditions. In doing so we construct a dual variational method. Problem considered relates to the problem of nonlinear eigenvalue.
A construction of an idempotent half-completion for quasi-uniform spaces
Authors: Andrikopoulos Athanasios
Published: August 2009

Császár (1963) and Deák (1991) have introduced the notion of half-completeness in quasi-uniform spaces which generalizes the well known notion of bicompleteness. In this paper, for any quasi-uniform space, we construct a half-completion, called standard half-completion. The standard half-completion coincides with the usual uniform completion in the case of uniform spaces. It is also an idempotent operation in the sense that the standard half-completion of a half-complete quasi-uniform space coincides (up to a quasi-isomorphism) with the space itself.
Some new characterizations of metrizable spaces
Authors: Shen Rongxin
Published: August 2009

In this paper, some new metrization theorems about regular networks are obtained, which improve related results in [2], [10], [15], and [20].
A new version of l. Fejes Tóth’s moment theorem
Authors: Böröczky Károly , Csikós Balázs
Published: August 2009

A version of the celebrated Moment Theorem of László Fejes Tóth is proved where the integrand is based not on the second moment but on another quadratic form.
On almost measurable real-valued functions
Authors: Kharazishvili Alexander
Published: August 2009

The notion of an almost measurable real-valued function is introduced and examined. Some properties of such functions are considered and their characterization is given. In particular, it is shown that the algebraic sum of two almost measurable functions can be a function without the property of almost measurability and that any almost measurable function becomes measurable with respect to an appropriate extension of the Lebesgue measure.
Approximation in statistical sense to B -continuous functions by positive linear operators
Authors: Dirik Fadime , Duman Oktay , Demirci Kamil
Published: August 2009

In the present work, using the concept ofA-statistical convergence for double real sequences, we obtain a statistical approximation theorem for sequences of positive linear operators defined on the space of all real valuedB-continuous functions on a compact subset of the real line. Furthermore, we display an application which shows that our new result is stronger than its classical version.