bluuebunny/crossref_metadata_2025 huggingface dataset:
Amae and Mardy
Authors: Lewis J. Rees , Ozaki Ritsuko
Published: December 2009

The Japanese term amae , referring to a need to receive affection, is compared to a Midland English dialect word, mardy, meaning soft or spoilt. An interpretative phenomenological analysis conducted within the framework of the componential model of emotion indicates areas of overlap and divergence between these two terms that reflect the attitudes toward dependence within the two cultural contexts. Antecedents are similar, as are some of the elements of subjective experience and emotional expression. Both are more or less appropriate in similar relationships. However, mardiness is less acceptable than amae: The former may be universal, but it is considered childish and therefore unacceptable; the latter may be childish, but it is considered human and is more often treated sympathetically.
Combining Qualitative and Quantitative Methods to Study Perceptions of Immigrant Youth
Authors: Roer-Strier Dorit , Kurman Jenny
Published: December 2009

This article illustrates the potential of combining qualitative and quantitative methods to increase understanding of social and cultural phenomena. An example of a multimethod study demonstrates the advantages of this combination. The study investigated perceptions of young people who immigrated to Israel from the former Soviet Union. The first stage of the study began as a quantitative study of role reversal in immigration and developed into a qualitative study investigating the subjective experiences involved in this phenomenon. An “alternatingmethod” model, in which a research effort alternates between qualitative and quantitative components, each stage building on the previous one, is proposed.
Pesach N. Rubenstein Cheats the Hangman: A Case Study of Punishment and the Death Penalty at Brooklyn’s Raymond Street Jail
Authors: Stinson Philip Matthew
Published: December 2009

This article tells the story of Pesach Rubenstein and how he cheated the hangman in 1876. Rubenstein was charged, tried, and convicted in Kings County, New York, for the 1875 murder of his 19-year-old cousin, Sarah Alexander. The Rubenstein case is noteworthy in that it received unprecedented media attention in the 1870s, involved the use of rudimentary forensic evidence at the trial, and divided the community on issues of religion, ethnicity, immigration (the victim and defendant were recent Jewish immigrants from Poland), and imposition of the death penalty. Using a case study approach to analyze the trial transcript, newspaper articles, and historical accounts of the murder investigation, Rubenstein’s trial, and his incarceration at Brooklyn’s Raymond Street Jail, this article offers a glimpse into the operations of an urban jail in an earlier era when our criminal justice system was in its infancy.
Beyond “Making It” or Not: Future Talk by Incarcerated Young Men
Authors: Gardner Joby
Published: December 2009

This article explores how incarcerated young men talked about the future. I use theories of cultural capital and methods informed by critical discourse analysis to analyze interviews with 15 young men and a series of essays about the future written by 10 different young men. It suggests new directions for analysis and programmatic use of future talk by and for incarcerated or similarly marginalized young people, specifically moving beyond well-established binaries of “making it” or “not making it,” which characterize research into marginalized young people’s aspirations, to focus instead on quieter but readily apparent future talk about “giving back” and “help[ing] others.”
Subjective Well-Being in Urban Adolescents: Interpersonal, Individual, and Community Influences
Authors: Morgan Melissa L. , Vera Elizabeth M. , Gonzales Rufus R. , Conner Wendy , Bena Vacek Kim , Dick Coyle Laura
Published: December 2009

This study examined the relationship between subjective well-being criteria (negative affect, positive affect, and subjective well-being) and individual, family, friend, school, and neighborhood predictor variables in 159 ethnically diverse, urban adolescents. Results indicated that negative affect was significantly predicted by family variables, positive affect was significantly predicted by individual, school, and friend variables, and satisfaction with life was significantly predicted by individual and family variables. Limitations, directions for future research, and clinical implications of these findings are discussed.
Tourism Use History: Exploring a New Framework for Understanding Residents’ Attitudes toward Tourism
Authors: Draper Jason , Woosnam Kyle M. , Norman William C.
Published: December 2009

This study attempts to answer the question “What influence does an individual’s travel have on attitudes concerning who should develop tourism in their community as well as the role of the government in such development?” Research on residents’ attitudes toward tourism has traditionally focused on demographic, socioeconomic, and spatial predictor variables, with relatively few consistent findings. Based on the experience use history concept from the leisure and outdoor recreation literature, this study explores a new framework for understanding residents’ attitudes toward tourism in two distinct destinations in South Carolina, United States. Tourism use history was used to create resident groups within each community and assess attitudes about who should develop tourism (e.g., local businesses, outside investors and developers, government, or a public—private partnership) and government support for tourism businesses. Results are discussed in relation to the stage of tourism development in each destination. Further development and testing of tourism use history is recommended.
The Role of TV Commercial Visuals in Forming Memorable and Impressive Destination Images
Authors: Pan Steve
Published: December 2009

Tourism TV commercials (TVCs) are one of the channels (or agents) used to form destination images, yet this channel is rarely researched.The objectives of this article are to identify the relations among visual elements,TVC effects, and destination image formation. University students who have never visited New Zealand nor watched New Zealand’s latest tourism TVCs were recruited to participate in a TVC recall test. The audience found video frames of snow and water, dolphins, and hongi (a traditional Maori greeting) to be most memorable and impressive. Findings suggest that something old (i.e., something familiar to viewers), something new (i.e., something that cannot be seen or done in the viewer’s immediate environment), and something white and something blue (i.e., clean and pristine) should be included when developing promotional tourism videos. Video frames showing people’s interaction among themselves and with the environment were positively related to audience desires to visit the depicted destination.
The Perception of the Army by Armenian Minorities Living in Turkey
Authors: Örs H. Birsen
Published: December 2009

This article analyzes the findings of the fourth part of a survey on Turkey’s Armenians, the largest non-Muslim minority group living in Turkey, conducted with the aim of understanding their perception of the Turkish Army and Officer Corps. In this article, the author argues that Turkey’s Armenians consider the Turkish Army as the most credible and trustworthy institution and a career as an officer as a desirable occupation. The findings of the survey, consisting of face-to-face in-depth interviews, questionnaires, and the author’s personal observations, are evaluated and interpreted throughout the article to support the argument.
Covariance 99mTc-Exametazime SPECT Patterns in Alzheimer’s Disease and Dementia with Lewy Bodies: Utility in Differential Diagnosis
Authors: Colloby Sean J. , Taylor John P. , Firbank Michael J. , McKeith Ian G. , Williams E. David , O'Brien John T.
Published: December 2009

99mTc-exametazime single photon emission computed tomography (SPECT) scans of 36 patients with Alzheimer’s disease (AD) and 30 with dementia with Lewy bodies (DLB) underwent region of interest (ROI) and principal component analysis (PCA). Principal component analysis was performed on the entire ROI data set. Principal components (PCs) were obtained, representing common intercorrelated regions in AD and DLB. Topographic expression that signified the extent to which a participant expressed the topographic covariance pattern was derived and used as a discriminatory variable. Principal components were identified, accounting for 77% of total data variance. Significant (PC × group) interaction was observed (P < .001). Topographic expression was significantly higher in DLB than AD (F1,64 = 21.6, P < .001), and differentiated DLB from AD with sensitivity 73% specificity 72%. Calculating the topographic expression in an independent data set of 48 patients with AD and 23 with DLB gave sensitivity = 70%, specificity = 67%. Principal component analysis captures additional sources of variance and if perfusion SPECT is the only scan available, this procedure may offer extra information.
How Do People Value Life?
Authors: Li Meng , Vietri Jeffrey , Galvani Alison P. , Chapman Gretchen B.
Published: December 2009

Who should be saved when health resources are limited? Although bioethicists and policymakers continue to debate which metric should be used to evaluate health interventions, public policy is also subject to public opinion. We investigated how the public values life when evaluating vaccine-allocation policies during a flu epidemic. We found that people’s ratings of the acceptability of policies were dramatically influenced by question framing. When policies were described in terms of lives saved, people judged them on the basis of the number of life years gained. In contrast, when the policies were described in terms of lives lost, people considered the age of the policy’s beneficiaries, taking into account the number of years lived to prioritize young targets for the health intervention. In addition, young targets were judged as more valuable in general, but young participants valued young targets even more than older participants did.
Effects of Yangtze River source water on genomic polymorphisms of male mice detected by RAPD
Authors: Xiaolin Zhang  , Zongyao Zhang  , Xuxiang Zhang  , Bing Wu  , Yan Zhang  , Liuyan Yang  , Shupei Cheng
Published: December 2009

In order to evaluate the environmental health risk of drinking water from Yangtze River source, randomly amplified polymorphic DNA (RAPD) markers were used to detect the effects of the source water on genomic polymorphisms of hepatic cell of male mice (Mus musculus, ICR). After the mice were fed with source water for 90 days, RAPD-polymerase chain reactions (PCRs) were performed on hepatic genomic DNA using 20 arbitrary primers. Totally, 189 loci were generated, including 151 polymorphic loci. On average, one PCR primer produced 5.3, 4.9 and 4.8 bands for each mouse in the control, the groups fed with source water and BaP solution, respectively. Compared with the control, feeding mice with Yangtze River source water caused 33 new loci to appear and 19 to disappear. Statistical analysis of RAPD printfingers revealed that Yangtze River source water exerted a significant influence on the hepatic genomic polymorphisms of male mice. This study suggests that RAPD is a reliable and sensitive method for the environmental health risk of Yangtze River source water.
A Comparison of Acute Lymphoblastic Leukemia in Down Syndrome and Non— Down Syndrome Children: The Role of Trisomy 21
Authors: Tigay Judith Harriet
Published: December 2009

Down syndrome (DS), which occurs once in every 800 births, is associated with a trisomy on locus 21. Among the many aberrations caused by DS, including shortened stature and distorted facies, are several blood dyscrasias, including childhood leukemias—namely, acute myeloid leukemia (AML) and acute lymphoblastic, or lymphocytic, leukemia (ALL). One focus of the diagnosis of ALL is to distinguish it from AML.The benefits of immunophenotyping extend to treatment as well. ALL is associated with an inherited trisomy 21 in DS children (ALL-DS) and with acquired trisomies, +21, 8, and 13, in non-DS children (ALL-NDS). The differences in treatment, outcome, and prognosis between ALL-DS and ALL-NDS can be attributed to the interaction of their respective trisomies with several genetic mutations, including one on the GATA1 growth factor transcription gene. Other mutations are the gene fusion at TEL/AML1, and a new mutation found, which labels the Janus Kinase gene or JAK2 as on oncogenic precursor, which when associated with the B-cell precursor gene or BCP is highly leukomogenic. The treatments for the 2 groups have been based on quality of risk, with ALL-DS children having the highest risk along with the poorest prognosis, but alterations in medication regimens have brought treatment outcomes to near equality. It is worthwhile to study the trisomy 21 because in the future it may provide an understanding of all blood dyscrasias.
Characterization of Semi-active Control System Dynamics with Magneto-rheological Suspensions
Authors: Song X. , Ahmadian M.
Published: December 2009

This paper characterizes two semi-active control algorithms through strategy analysis and parametric simulation study. A brief literature review discloses two kinds of semi-active controls: non-model based skyhook-like control policy (or skyhook variations), and model-based clipped semi-active control strategies. Both can be formulated as a bi-state control algorithm. In this paper, the no-jerk skyhook control policy is chosen to represent bi-state strategies, while a nonlinear adaptive semi-active control algorithm without need of clipping control signals is selected for comparison study. Then the studied MR suspension and its model setup are presented. In the paper we explain dynamic analysis approach and controller tuning for this simulation study. While analytic analysis of strategies is based on linear base-excited vibration systems by using transmissibility plots, simulation study adopts sine-sweep excitations so that comparison of transient dynamics could be stressed out and simultaneously the vibration isolation capability compared in the frequency domain by directly observing the time domain data. In addition, one pure-tone excitation case is simulated to explain higher harmonics inherent with bi-state skyhook controls. From the simulation study, the effectiveness of both semi-active controls can be observed for vibration isolation. In addition, the adaptability of both selected controls is compared regarding plant variations and different excitation profiles, both of which are typical in vehicle suspension systems. Finally the characteristics of these two semi-active controls are summarized from the simulation findings.
Adaptive Discrete Sliding Mode Control for Mechanical Systems with Mismatched Uncertainties
Authors: Yoshimura Toshio
Published: December 2009

This paper is concerned with an adaptive discrete sliding mode control (SMC) for mechanical systems with mismatched uncertainties. It is assumed that the mechanical systems to be considered here are described by a discrete-time state equation with uncertainties found in unmodeled dynamics and external disturbances, and the states are measured in the contamination with independent random noises. The uncertainties are expressed in a parameterized form, and the estimates for the states and the uncertainties are taken by using the proposed weighted least squares estimator (WLSE). The proposed adaptive discrete SMC is constructed on the basis of the estimates obtained by the proposed WLSE. It is verified by using the Lyapunov method that the estimation error equation is asymptotically stable, and the mechanical systems are ultimately bounded under the action of the proposed adaptive discrete SMC. The effectiveness of the proposed method is indicated by the simulation experiment in the application to the design of an active suspension system for one-wheel car models.
Turbocharger On-engine Experimental Vibration Testing
Authors: Kirk R. Gordon , Kornhauser Alan A. , Sterling John , Alsaeed Ali
Published: December 2009

Many automotive turbochargers operate in the self-excited unstable region. In the past these instabilities have been accepted as unavoidable, but recent developments in analysis and instrumentation may make it possible to reduce or eliminate them. A test stand being developed at Virginia Tech has been used to measure the vibrations of a 3.9 liter diesel engine stock turbocharger with floating bushing journal bearings. Vibration spectrum content clearly identifies the shaft instabilities and provides the basis for additional evaluation of future bearing design modifications. This paper provides additional experimental vibration data reduction that will be useful for future research direction to fully understand the turbocharger dynamic instability.
Influence of HLA-DRB1 alleles on the susceptibility and resistance to multiple sclerosis in Japanese patients with respect to anti-aquaporin 4 antibody status
Authors: Isobe N. , Matsushita T. , Yamasaki R. , Ramagopalan SV , Kawano Y. , Nishimura Y. , Ebers GC , Kira J.
Published: December 2009

Background: Epistatic interactions between human leukocyte antigen (HLA)-DRB1 alleles alter multiple sclerosis (MS) risk in Caucasians. Such interactions have never been studied in Asian MS patients.

Objective: To investigate the influence of HLA-DRB1 alleles, including epistatic interactions at this locus, in Japanese MS patients with and without the anti-aquaporin 4 (AQP4) antibody.

Methods: The HLA-DRB1 locus was genotyped in 108 MS patients and 127 healthy controls. MS patients were further classified into two groups according to anti-AQP4 antibody status (27 positive and 81 negative).

Results: HLA-DRB1*09 (adjusted odds ratio (OR) = 0.243, 95% confidence interval (CI) 0.099—0.533) and HLA-DRB1*01 (adjusted OR = 0.327, 95% CI 0.103—0.873) decreased the incidence of anti-AQP4 antibody-negative MS. By contrast, HLA-DRB1*12 increased the risk of anti-AQP4 antibody-positive MS (adjusted OR = 3.691, 95% CI 1.233—10.565). Individuals with HLA-DRB1*09/15 decreased the risk of anti-AQP4 antibody-negative MS (adjusted OR = 0.164, 95% CI 0.026—0.593), while those with HLA-DRB1*12/15 increased the risk of anti-AQP4 antibody-positive MS (adjusted OR = 10.870, 95% CI 2.004—81.752).

Conclusions: The ability of HLA-DRB1*09 to reduce the risk of anti-AQP4 antibody-negative MS may arise from an interaction with HLA-DRB1*15. By contrast, HLA-DRB1*12 increases susceptibility to anti-AQP4 antibody-positive MS, possibly via an interaction with HLA-DRB1*15.
Identification of mammalian orthologs using local synteny
Authors: Jun Jin , Mandoiu Ion I , Nelson Craig E
Published: December 2009

Background

Accurate determination of orthology is central to comparative genomics. For vertebrates in particular, very large gene families, high rates of gene duplication and loss, multiple mechanisms of gene duplication, and high rates of retrotransposition all combine to make inference of orthology between genes difficult. Many methods have been developed to identify orthologous genes, mostly based upon analysis of the inferred protein sequence of the genes. More recently, methods have been proposed that use genomic context in addition to protein sequence to improve orthology assignment in vertebrates. Such methods have been most successfully implemented in fungal genomes and have long been used in prokaryotic genomes, where gene order is far less variable than in vertebrates. However, to our knowledge, no explicit comparison of synteny and sequence based definitions of orthology has been reported in vertebrates, or, more specifically, in mammals.

Results

We test a simple method for the measurement and utilization of gene order (local synteny) in the identification of mammalian orthologs by investigating the agreement between coding sequence based orthology (Inparanoid) and local synteny based orthology. In the 5 mammalian genomes studied, 93% of the sampled inter-species pairs were found to be concordant between the two orthology methods, illustrating that local synteny is a robust substitute to coding sequence for identifying orthologs. However, 7% of pairs were found to be discordant between local synteny and Inparanoid. These cases of discordance result from evolutionary events including retrotransposition and genome rearrangements.

Conclusions

By analyzing cases of discordance between local synteny and Inparanoid we show that local synteny can distinguish between true orthologs and recent retrogenes, can resolve ambiguous many-to-many orthology relationships into one-to-one ortholog pairs, and might be used to identify cases of non-orthologous gene displacement by retroduplicated paralogs.
Are there geographic and socio-economic differences in incidence, burden and prevention of malaria? A study in southeast Nigeria
Authors: Onwujekwe Obinna , Uzochukwu Benjamin , Dike Nkem , Okoli Chijioke , Eze Soludo , Chukwuogo Ogoamaka
Published: December 2009

Rationale

It is not clearly evident whether malaria affects the poor more although it has been argued that the poor bear a very high burden of the disease. This study explored the socioeconomic and geographic differences in incidence and burden of malaria as well as ownership of mosquito nets.

Methods

Structured questionnaires were used to collect information from 1657 respondents from rural and urban communities in southeast Nigeria on: incidence of malaria, number of days lost to malaria; actions to treat malaria and household ownership of insecticide treated and untreated mosquito nets. Data was compared across socio-economic status (SES) quartiles and between urban and rural dwellers.

Results

There was statistically significant urban-rural difference in malaria occurrence with malaria occurring more amongst urban dwellers. There was more reported occurrence of malaria amongst children and other adult household members in better-off SES groups compared to worse-off SES groups, but not amongst respondents. The average number of days that people delayed before seeking treatment was two days, and both adults and children were ill with malaria for about six days. Better-off SES quartile and urban dwellers owned more mosquito nets (p < 0.05) (treated and untreated).

Conclusion

Malaria occurs more amongst better-off SES groups and urban dwellers in southeast Nigeria. Deployment of malaria control interventions should ensure universal access since targeting the poor and other supposedly vulnerable groups may exclude people that really require malaria control services.
Systematic review of epidemiological studies on health effects associated with management of solid waste
Authors: Porta Daniela , Milani Simona , Lazzarino Antonio I , Perucci Carlo A , Forastiere Francesco
Published: December 2009

Background

Management of solid waste (mainly landfills and incineration) releases a number of toxic substances, most in small quantities and at extremely low levels. Because of the wide range of pollutants, the different pathways of exposure, long-term low-level exposure, and the potential for synergism among the pollutants, concerns remain about potential health effects but there are many uncertainties involved in the assessment. Our aim was to systematically review the available epidemiological literature on the health effects in the vicinity of landfills and incinerators and among workers at waste processing plants to derive usable excess risk estimates for health impact assessment.

Methods

We examined the published, peer-reviewed literature addressing health effects of waste management between 1983 and 2008. For each paper, we examined the study design and assessed potential biases in the effect estimates. We evaluated the overall evidence and graded the associated uncertainties.

Results

In most cases the overall evidence was inadequate to establish a relationship between a specific waste process and health effects; the evidence from occupational studies was not sufficient to make an overall assessment. For community studies, at least for some processes, there was limited evidence of a causal relationship and a few studies were selected for a quantitative evaluation. In particular, for populations living within two kilometres of landfills there was limited evidence of congenital anomalies and low birth weight with excess risk of 2 percent and 6 percent, respectively. The excess risk tended to be higher when sites dealing with toxic wastes were considered. For populations living within three kilometres of old incinerators, there was limited evidence of an increased risk of cancer, with an estimated excess risk of 3.5 percent. The confidence in the evaluation and in the estimated excess risk tended to be higher for specific cancer forms such as non-Hodgkin's lymphoma and soft tissue sarcoma than for other cancers.

Conclusions

The studies we have reviewed suffer from many limitations due to poor exposure assessment, ecological level of analysis, and lack of information on relevant confounders. With a moderate level confidence, however, we have derived some effect estimates that could be used for health impact assessment of old landfill and incineration plants. The uncertainties surrounding these numbers should be considered carefully when health effects are estimated. It is clear that future research into the health risks of waste management needs to overcome current limitations.
MTHFR C677T and postmenopausal breast cancer risk by intakes of one-carbon metabolism nutrients: a nested case-control study
Authors: Maruti Sonia S , Ulrich Cornelia M , Jupe Eldon R , White Emily
Published: December 2009

Introduction

The C677T polymorphism of the methylenetetrahydrofolate reductase (MTHFR) gene has been hypothesized to increase breast cancer risk. However, results have been inconsistent, and few studies have reported the association by menopausal status or by intakes of nutrients participating in one-carbon metabolism. Our aims were to investigate whether MTHFR C677T was associated with postmenopausal breast cancer risk and whether this relation was modified by intakes of folate, methionine, vitamins B2, B6, and B12, and alcohol.

Methods

We studied 318 incident breast cancer cases and 647 age- and race-matched controls participating in a nested case-control study of postmenopausal women within the VITamins And Lifestyle (VITAL) cohort. Genotyping was conducted for MTHFR C677T and dietary and supplemental intakes were ascertained from a validated questionnaire. Adjusted odds ratios (OR) and 95% confidence intervals (CI) were calculated using unconditional logistic regression.

Results

We observed a 62% increased risk of breast cancer among postmenopausal women with the TT genotype (OR = 1.62; 95% CI: 1.05 to 2.48). Women with a higher number of variant T alleles had higher risk of breast cancer (P for trend = 0.04). Evidence of effect-modification by intakes of some B vitamins was observed. The most pronounced MTHFR-breast cancer risks were observed among women with the lowest intakes of dietary folate (P for interaction = 0.02) and total (diet plus supplemental) vitamin B6 (P for interaction = 0.01), with no significant increased risks among women with higher intakes.

Conclusions

This study provides support that the MTHFR 677TT genotype is associated with a moderate increase in risk of postmenopausal breast cancer and that this risk may be attenuated with high intakes of some one-carbon associated nutrients.
Pareto simulated annealing and colonial competitive algorithm to solve an offline scheduling problem with rejection
Authors: Jolai F , Sangari M S , Babaie M
Published: December 2009

The present paper considers the problem of scheduling a set of jobs where some jobs may be rejected. The objective function consists of minimizing two criteria simultaneously: the sum of the weighted completion times of the accepted jobs and the sum of the rejection costs. Although the characteristics of this problem have been discussed in the literature, no solution algorithm has yet been proposed. Herein, solution algorithms are developed using two meta-heuristic methods: Pareto simulated annealing (PSA), a multiple-objective optimization approach; and colonial competitive algorithm (CCA), a novel method which is adopted for the first time in a discrete multiple-objective optimization problem. Computational testing illustrates the practicality of both algorithms to find a good estimation of the Pareto optimal set. The quality of the proposed algorithms are evaluated and compared by some available performance measures and a new measure introduced in the paper. The comparative results show that CCA offers better estimation of the Pareto optimal set than PSA.
Aerodynamic performance of a bypass engine with fan nozzle exit area change by warped chevrons
Authors: Sloan B , Wang J , Spence S , Raghunathan S , Riordan D
Published: December 2009

Variation of the bypass nozzle exit area enables optimization of the turbofan engine operating cycle over a wider range of operational conditions resulting in improved thrust and/or fuel consumption. Two mechanisms for varying the nozzle area have been investigated. The first uses an array of chevrons which when closed, form a full body of revolution and when warped/curved, increase the exit area while forming a serrated trailing edge. The second technique incorporates an axially translating section of the nacelle shroud and uses the change in the nozzle boat-tail radial location with the axial location as a means to vary the nozzle exit area. To analyse the effects on a typical rotor/stator stage, computational fluid dynamics simulations of the NASA Rotor 67, Stator 67A stage integrated into a custom-built nacelle were performed. Nozzles with 8, 12, and 16 chevrons were simulated to evaluate the impact of the variation in geometry upon the nacelle wake and local forces. Gross thrust of the nacelle and the turbulent kinetic energy (TKE) variation through the wake is compared. The chevron nozzle attains a nearly 2 per cent maximum thrust improvement over the translating nozzle technique. The chevron nozzle also has significantly lower (nearly 8 per cent) peak TKE levels in the jet plume.
Phosphor thermometry in gas turbines: Consideration factors
Authors: Khalid A H , Kontis K , Behtash H-Z
Published: December 2009

There is an increasing demand for turbine engines with improved performance and efficiency. Gas turbine efficiencies can be increased if higher turbine inlet temperatures are achieved. However, the optimum temperature is prescribed by the balance between the benefits of thermal efficiency and material life. Accurate thermal maps can allow engines to operate closer to their design limit, and greatly facilitate the design of improved engines. This article provides a review highlighting the advantages and rationale of using phosphor thermometry over existing temperature measurement techniques, such as thermocouple and pyrometry. Although phosphor thermometry exhibits excellent characteristics to make accurate measurements, the high temperature and fast rotating engine environment presents some challenges with interrelated issues that would need to be collectively considered before a successful measurement system can be implemented. Examples include extreme blackbody radiation, restricted optical access and time to collect data, etc. These factors will impose temperature limits and greatly influence the design philosophy of the measurement system, including phosphor choice, bonding technique, excitation/detection methodologies, and probe design. This article aims to provide an overview of these consideration factors, with supplementary design notes and guidance to aid engineers design and develop successful phosphor thermometry measurement systems for such environments.
Non-linear and adaptive flight control of autonomous aircraft using invariant manifolds
Authors: Karagiannis D , Astolfi A
Published: December 2009

This article presents a novel non-linear and adaptive control scheme for the stabilization, command following, and trajectory tracking of autonomous aerial vehicles. The main feature of the proposed flight control system is that it consists of a single non-linear adaptive control law covering the entire flight envelope and does not require accurate knowledge of the aerodynamic coefficients, which are estimated on-line. The design follows a recently developed adaptive control framework that is based on the notion of invariant manifold and provides a modular controller-estimator structure that is relatively easy to tune. The proposed scheme is tested via simulations on two different models of unmanned aerial vehicles: the XRAE-140 and the Eclipse flight demonstrator.
Conceptual design of a medium-sized joined-wing aircraft
Authors: Cuerno-Rejado C , Alonso-Albir L , Gehse P
Published: December 2009

The joined-wing aircraft is a very promising concept to reduce the ever-increasing fuel costs and CO2 emissions. Joined-wing aircraft employ tandem wings having positive and negative sweep and dihedral, arranged to form diamond shapes in both plan and front views. This article evaluates its capabilities by establishing a comparison with respect to a reference conventional wing-plus-horizontal tail aircraft. Both airplanes are designed for the same medium-/long-range transport mission. The topics considered include structural arrangement, weights and aerodynamic characteristics, as well as operational issues, such as performance and direct operating costs. The conclusions drawn at the end of this preliminary study are very positive, but further research is required in order to confirm some hypotheses regarding the structural arrangement.
Analytical solutions for two-point boundary value problems: Optimal low-thrust orbit transfers
Authors: Shafieenejad I , Novinzadeh A B
Published: December 2009

A new guidance scheme for the problem of low-thrust transfer between inclined orbits is developed within the framework of optimal control theory. The objective of the guidance scheme is to provide the appropriate thrust steering program that will transfer the vehicle from inclined low earth orbits to high earth orbits. The presented guidance scheme is determined using Pontryagin's principle such that three desired performance measures are minimized and boundary conditions for this unspecified final time problem are satisfied. One of the novelties of this work is changing the independent variable from time to thrust angle and considering properties of autonomous system equations to reduce to one where an exact analytical solution is obtained. Finally, three performance measure results are compared and the best policy is proposed.
Influence of chemical models on the computation of thermo-fluid-dynamic parameters in hypersonic, rarefied flows
Authors: Zuppardi G , Morsa L , Romano F
Published: December 2009

Four different chemical models (Bird, Fan and Shen, ‘classic’, and ‘new’ quantic) have been implemented in a direct simulation Monte Carlo (DSMC) code for comparison purpose. Computer tests simulated a hypersonic, rarefied flow field past a bluff (or flat-ended) cylinder; the working gas was nitrogen. The flow field parameters were compared with those from the advanced DS2V code. The Stanton number at the stagnation point was compared also with the experimental data. The present analysis showed that the Fan—Shen model is comparable with the widely accepted Bird model. The results from the DSMC code based on these models are close to those computed by DS2V and to the experimental data. The good comparison of the Bird and the Fan—Shen models is a very important result both from a physical point of view, because the two models rely on different approaches, and from an operative point of view, because the Fan—Shen model could be considered as a possible alternative to the Bird model. On the contrary, the quantic models appear to be not suitable.
Dimensionless flow equations for dynamic simulation of turbomachine components and fluid systems
Authors: Puddu P
Published: December 2009

In this work, a dimensionless form of the equations of motion used for dynamic simulation of turbomachine components is presented. The dimensionless equations are obtained from the governing equations of unsteady compressible viscous one-dimensional flow by defining three variables of state that have a direct link with the variables measured in the experimental investigations: total pressure, total temperature, and the Mach number. The new dimensionless form of equations presents the characteristics of generality that makes it easy to apply to many fluid dynamic problems. The application of dimensionless equations to more complex systems can be simplified and made easier by using the lumped parameter discretization method.

Another important feature of the dimensionless system of equations is that it can be solved explicitly without any iterative process within each step of integration, thus making it easier and faster during dynamic simulations. The equations can be further simplified in the case of stationary flows for which some examples of application are given in order to highlight the generality of the method and its ease of application.
Optimization of thermoacoustic stacks for low onset temperature engines
Authors: Yu Z , Jaworski A J
Published: December 2009

Standing-wave thermoacoustic engines are typically optimized in order to obtain high system efficiency. However, in applications targeting the utilization of waste heat, it may be necessary to optimize them for a low onset temperature difference instead, so as to enable the engine's self-oscillation using low-grade energy sources. This article focuses on theoretical investigations of the critical temperature gradient in stacks, based on the assumptions of a short stack in a standing-wave acoustic field and an ideal gas. A dimensionless critical temperature gradient factor is obtained on the basis of the linear thermoacoustic theory and the analysis of the viscous and thermal relaxation losses for selected stack geometries. With a simple form, it reveals the effects of the stack geometry, the characteristic channel dimension, and the local acoustic impedance on the critical temperature gradient of the stack. In particular, it is shown that the impedance determines the proportion between the viscous loss, heat relaxation losses, and the power production from the heat energy. Numerical analysis based on this dimensionless factor clearly shows that there is an optimum channel dimension for each given stack location in the acoustic field. There exists a possible optimum combination of these parameters, which leads to the lowest critical temperature gradient.
Rolling contact fatigue and wear fundamentals for rolling bearing diagnostics - state of the art
Authors: Halme J , Andersson P
Published: December 2009

Rolling bearing operation is affected by friction, wear and lubrication mechanisms, fluid dynamics and lubricant rheology, material properties, and contact mechanics. Changes in rolling surfaces occur due to plastic deformation, rolling contact wear, and rolling contact fatigue. Wear particles can be formed and mixed into the lubricant. Increased levels of vibrations due to surface degradation can be monitored by sensors. Rolling contact wear and rolling contact fatigue during rolling bearing operation can be diagnosed by combining measured and interpreted condition monitoring data with theory, and conclusions drawn thereof can support a continuous prognosis for the remaining bearing life. In the present work, connections between bearing diagnostics and tribological mechanisms are outlined.
Modelling the vehicle in vehicle—infrastructure dynamic interaction studies
Authors: Cantero D , O'Brien E J , González A
Published: December 2009

This article presents the equations of motion for a general articulated road vehicle, with variable number of wheels for the tractor and trailer. The equations are applicable to vehicle—infrastructure dynamic interaction problems for two- and three-dimensional systems, allowing for the definition of a wide variety of vehicle configurations with the same formulae.
Intergenerational Networks, Unemployment, and Persistent Inequality in South Africa
Authors: Magruder Jeremy R.
Published: December 2009

This paper examines the importance of network-based intergenerational correlations in South Africa. I use longitudinal data on young South Africans to examine the covariance of children's employment with the usefulness of parents in their job search. I find that fathers serve as useful network connections to their sons (not daughters), and that mothers do not seem to be useful network connections. The father-son effect is robust to alternate explanations of specific human capital and correlated networks. The size of this effect is large. Present fathers' utility as network connections may be responsible for a one-third increase in their sons' employment rates. (JEL D31, J12, J13, J24, J62, O15, Z13)
Prevalence of Mycoplasma genitalium among HIV-infected men in São Paulo city detected by realtime polymerase chain reaction
Authors: da Costa F A M , da Silva R C , Arruda L B , Montanheiro P , da Silva Duarte A J , Casseb J
Published: December 2009

Genital mycoplasmas are natural inhabitants of the male urethra and are potentially pathogenic species playing an aetiological role in both genital infections and male infertility. This study aims to determine the presence of Mycoplasma genitalium DNA in urine samples of HIV-1-infected men in São Paulo city. Realtime polymerase chain reaction (PCR) was performed using the primers My-ins and Mgso-2 and the Taqman probe Mgen-P1 as described previously. A total of 223 HIV-1-infected men were tested with a mean age of 44 years. Thirteen (5.8%) presented M. genitalium in urine and the co-infection was more common among homosexual men (76.9% versus 51.9%, P < 0.26). In conclusion, realtime PCR was a useful and rapid method for detecting M. genitalium DNA in urine samples. Further studies should be conducted to assess the clinical significance of these results on HIV transmission and its impact on HIV viral load.
Hepatic encephalopathy as an unusual late complication of transjugular intrahepatic portosystemic shunt insertion for non-cirrhotic portal hypertension caused by nodular regenerative hyperplasia in an HIV-positive patient on highly active antiretroviral therapy
Authors: Ding A , Lee A , Callender M , Loughrey M , Quah S P , Dinsmore W W
Published: December 2009

Transjugular intrahepatic portosystemic shunt (TIPS) is an artificially created conduit between the portal and systemic vascular system in the liver performed percutaneously via radiological guidance. It is used mainly in conditions causing portal hypertension and its resulting complications. It reduces portal pressure by diverting portal blood flow into the systemic circulation. Hepatic encephalopathy is the most common complication following TIPS insertion and tends to present fairly early. We describe a case of hepatic encephalopathy as an unusual late complication of TIPS insertion (first presenting six years after) for non-cirrhotic portal hypertension caused by nodular regenerative hyperplasia in an HIV-positive patient on highly active antiretroviral therapy.
More than a decade on: review of the use of imiquimod in lower anogenital intraepithelial neoplasia
Authors: Mahto M , Nathan M , O'Mahony C
Published: December 2009

To assess the effectiveness of 5% imiquimod cream (IQ) in the treatment of vulvar, penile and anal intraepithelial neoplasias (VIN, PIN and AIN), we searched Medline, Embase, PubMed and Cochrane Library databases. With regard to VIN there were two randomized controlled trials (RCTs), eight uncontrolled/cohort studies, nine case reports and one review article. Use of IQ in PIN and AIN were only supported by cohort studies (two each for PIN and AIN) and case reports (15 for PIN and 3 for AIN). On pooled analysis of RCTs, uncontrolled and cohort studies, the mean complete response (CR) rate for VIN, PIN and AIN were 51%, 70% and 48%, respectively. The mean partial response (PR) rate for VIN, PIN and AIN were 25%, 30% and 34% respectively. The recurrence (RR) rate for VIN, PIN and AIN were 16%, 0% and 36%, respectively. The follow-up period for VIN, PIN and AIN ranged from 2 to 32 months, 10 to 12 months and 11 to 39 months, respectively. Although the results for PIN look the best, the strongest evidence regarding efficacy of IQ in anogenital intraepithelial neoplasia is for VIN supported by RCTs. Evidence for use of IQ in AIN was essentially limited to HIV-positive men who have sex with men. IQ was reasonably well tolerated with side-effects being managed with reduction in frequency of drug usage and/or rest periods. Based on these results, IQ seems to be a safe mode of treatment and is possibly an alternative to currently available methods of treatment. However, there are no comparative studies assessing its efficacy against traditional modes of treatment.
Alfred Russel Wallace (1823–1913): evolution and medicine
Authors: O'Connell Henry P
Published: December 2009

The theory we now know simply as ‘evolution’ was first presented to the scientific world one and a half centuries ago, on 1 July 1858, when the work of two men, Alfred Russel Wallace and Charles Robert Darwin (1809–82), was jointly read at the Linnean Society. While Charles Darwin has rightly taken his place in history as one of the greatest scientists of all time, Alfred Russel Wallace has been largely forgotten outside of the scientific community. However, Wallace was a prolific researcher and writer with interests in a wide range of topics, from medicine to economics.
Did one ear infection in France change the history of Britain? The illness and death of Francis II (1544–60)
Authors: Srouji Ibrahim Albert
Published: December 2009

The middle ear has long been considered a continuum of the upper respiratory tract and modern physicians recognize the impact of upper respiratory tract pathology on the middle ear and are familiar with the possible neurosurgical complications of any resultant chronic or acute middle ear infection. In the 16th century, lack of this knowledge may have led to a sequence of events and one of the most important turning points for the British monarchy. This paper on the illness and death of King Francis II of France uncovers interesting aspects of ENT practice from the French Renaissance period and the intrigue surrounding this royal patient's well-documented but little discussed illness.
Sarcophilia, cremation and Sir Henry Thompson (1820–1904)
Authors: Jellinek E H
Published: December 2009

Sarcophilia, a neologism for an attachment to human remains, is set in a review of the history of the disposal of the dead. The ancient practice of cremation was relaunched late in the 19th century by the urological surgeon cum social reformer Sir Henry Thompson. He was stimulated by Edwin Chadwick and Charles Dickens, and by Charles Darwin's observations on the earthworm. Sarcophilia is the reason for the controversial Human Tissue Act of 2004.
Jules Bordet (1870–1961): a bridge between early and modern immunology
Authors: Schmalstieg Frank C , Goldman Armond S
Published: December 2009

Jules Bordet, a pioneering immunologist, lived until the dawn of molecular immunology. He was born in Belgium in 1870, obtained a medical degree in 1892, worked at l'Institut Pasteur in Paris from 1894 to 1901 and then established the Pasteur Institute of Brabant in Brussels. Before World War I, Bordet found that complement binds to antibody-antigen complexes regardless of the antigen or antibodies involved. Subsequently he developed the complement fixation test that was of diagnostic importance for several decades. For his research concerning complement he was awarded the 1919 Nobel Prize in Physiology or Medicine. During that period he also discovered anaphylatoxin, conglutinin, and the cause of whooping cough ( Bordetella pertussis). After World War I he found how thrombin forms, how platelets participate in clotting, lysozyme in human milk and much of the biology of bacteriophages. In addition, Bordet worked fervently to limit weapons of mass destruction and promote peace until his death in 1961.