bluuebunny/crossref_metadata_2025 huggingface dataset:
An Appeal to Aid Specialists
Authors: Horton Keith
Published: December 2009

The appeal I am making is (roughly speaking) for aid specialists to do more to help those of us who are not aid specialists to arrive at judgments about the effects of the work of (voluntary) aid agencies that we have at least some reason to think accurate. I argue that the fact that it is so difficult for us to arrive at such judgments at present has certain negative consequences, and that this gives those who are in a position to make it easier for us to arrive at such judgments strong reasons to do so. And I argue that (certain) aid specialists are in such a position. Hence my appeal to them to do so.
‘Knowledge’ or Knowledgeable Banks? International Financial Institutions' Generation of Knowledge in Times of Crisis
Authors: Cuesta José
Published: December 2009

The food‐price crisis is testing the capacity of so‐called ‘knowledge institutions’ to generate relevant knowledge with which to serve their clients better. This article analyses the voluminous knowledge generated by such banks and other international institutions in the context of the food‐price crisis: in particular, its technical features; the depth and merits of the subsequent policy discussion; and the connection between the knowledge generated and specific policy advocacy. It also provides an explanation for the inability of these institutions to anticipate the dire consequences of the crisis, other than the widely accepted ‘perfect storm’ storyline.
Tax Reform, Delocation, and Heterogeneous Firms*
Authors: Baldwin Richard , Okubo Toshihiro
Published: December 2009

The standard international tax model is extended to allow for heterogeneous firms when agglomeration forces are important, enabling us to study the relocation effects of taxes that vary according to firm size. We show that allowing for heterogeneity permits a given tax scheme to have an endogenously different effect on the location decision of small and big firms, with the biggest firms being endogenously more likely to relocate in reaction to high taxes. We show that a reform that flattens the tax–firm–size profile can raise tax revenue without inducing any relocation.
Can Production Subsidies Explain China's Export Performance? Evidence from Firm‐level Data*
Authors: Girma Sourafel , Gong Yundan , Görg Holger , Yu Zhihong
Published: December 2009

This paper analyses the relationship between production subsidies and firms’ export performance using a very comprehensive and recent firm‐level database and controlling for the endogeneity of subsidies. It documents robust evidence that production subsidies stimulate export activity at the intensive margin, although this effect is conditional on firm characteristics. In particular, the positive relationship between subsidies and the intensive margin of exports is strongest among profit‐making firms, firms in capital‐intensive industries, and those located in non‐coastal regions. Compared to firm characteristics, the extent of heterogeneity across ownership structure (SOEs, collectives, and privately owned firms) proves to be relatively less important.
Firm Heterogeneity, Contract Enforcement, and the Industry Dynamics of Offshoring*
Authors: Naghavi Alireza , Ottaviano Gianmarco
Published: December 2009

We develop an endogenous growth model with R&D spillovers to study the long‐run consequences of offshoring with firm heterogeneity and incomplete contracts. In so doing, we model offshoring as the geographical fragmentation of a firm's production chain between a home upstream division and a foreign downstream division. While there is always a positive correlation between upstream bargaining weight and offshoring activities, there is an inverted U‐shaped relationship between these and growth. Whether offshoring with incomplete contracts also increases consumption depends on firm heterogeneity. As for welfare, whereas with complete contracts an R&D subsidy is enough to solve the inefficiency due to R&D spillovers, with incomplete contracts a production subsidy is also needed.
Foreign Direct Investment and the Incentives to Innovate and Imitate*
Authors: Brambilla Irene , Hale Galina , Long Cheryl
Published: December 2009

We propose a new channel of FDI spillovers on domestic firms, which operates through imitation of original products. Domestic heterogeneous firms may not introduce any new products, introduce a new product line (innovate), or develop a variety that is a close substitute to an existing product line (imitate). The presence of foreign firms generates incentives for imitation because they introduce original products that are vertically differentiated from domestic products. Using firm‐level panel data for China, we find that increased FDI presence in a given industry leads to more imitation, but not necessarily more innovation, by domestic firms.
Attitudes towards new HIV biomedical prevention technologies among a cohort of HIV‐negative gay men in Sydney, Australia
Authors: Poynten IM , Jin F , Prestage GP , Kaldor JM , Imrie J , Grulich AE
Published: December 2009

Objectives

The aim of the study was to explore the awareness of rectal microbicides, the use of pre‐exposure prophylaxis (PREP) and the willingness to participate in biomedical HIV prevention trials in a cohort of HIV‐negative gay men.

Methods

In a community‐based cohort study, HIV‐negative homosexually active men in Sydney, Australia were questioned about awareness of rectal microbicides, use of PREP, and willingness to participate in trials of such products. Predictors of awareness and willingness to participate were analysed by logistic regression. Use of PREP was examined prospectively.

Results

Overall, 14% had heard of rectal microbicides. Older (P=0.05) and university‐educated men (P=0.001) were more likely to have knowledge of rectal microbicides. Almost one‐quarter (24%) of men reported that they were likely/very likely to participate in rectal microbicide trials. Among those men with definite opinions on participation, awareness of rectal microbicides was significantly associated with unwillingness to participate [odds ratio (OR) 0.78, 95% confidence interval (CI) 0.65–0.93, P=0.007]. Willingness to participate in trials using antiretroviral drugs (ARVs) to prevent HIV infection was reported by 43% of men, and was higher among those who reported unprotected anal intercourse (UAI) with HIV‐positive partners (OR 1.88, 95% CI 0.99–3.56). There was no evidence of current PREP use.

Conclusions

This study demonstrates that Australian gay men have had little experience with PREP use and rectal microbicides. About half would be willing to consider participation in trials using ARVs to prevent HIV infection. Extensive community education and consultation would be required before PREP or rectal microbicides could be trialled in populations of gay Australian men.
A framework for comparing pollinator performance: effectiveness and efficiency
Authors: Ne'eman Gidi , Jürgens Andreas , Newstrom‐Lloyd Linda , Potts Simon G. , Dafni Amots
Published: December 2009

Measuring pollinator performance has become increasingly important with emerging needs for risk assessment in conservation and sustainable agriculture that require multi‐year and multi‐site comparisons across studies. However, comparing pollinator performance across studies is difficult because of the diversity of concepts and disparate methods in use. Our review of the literature shows many unresolved ambiguities. Two different assessment concepts predominate: the first estimates stigmatic pollen deposition and the underlying pollinator behaviour parameters, while the second estimates the pollinator's contribution to plant reproductive success, for example in terms of seed set. Both concepts include a number of parameters combined in diverse ways and named under a diversity of synonyms and homonyms. However, these concepts are overlapping because pollen deposition success is the most frequently used proxy for assessing the pollinator's contribution to plant reproductive success. We analyse the diverse concepts and methods in the context of a new proposed conceptual framework with a modular approach based on pollen deposition, visit frequency, and contribution to seed set relative to the plant's maximum female reproductive potential. A system of equations is proposed to optimize the balance between idealised theoretical concepts and practical operational methods. Our framework permits comparisons over a range of floral phenotypes, and spatial and temporal scales, because scaling up is based on the same fundamental unit of analysis, the single visit.
Management of blood supplies during an influenza pandemic
Authors: Kamp Christel , Heiden Margarethe , Henseler Olaf , Seitz Rainer
Published: December 2009

BACKGROUND: Blood supplies are delicate resources, particularly vulnerable to incidents affecting the health of donors. The critical impact of a pandemic on the availability of red blood cells (RBCs) has been demonstrated in previous research; however, a detailed estimate of the expected deficit is missing. This has become a priority issue in the face of the current influenza pandemic.

STUDY DESIGN AND METHODS: Data from several major blood donation services were used to analyze management of blood supplies in Germany. Routine management of RBCs was extrapolated to epidemic and pandemic situations using computer simulations with a mathematical model that allows for analysis of deficits in blood supplies.

RESULTS: Routine management and distribution of RBCs are driven by supply, which has marked fluctuations but does not appear to have seasonality. There seems to be a remarkable elasticity in the demand for RBCs that helps to mitigate minor crises in supply, but this is likely to be overstretched during a severe pandemic.

CONCLUSION: The supply‐driven management of RBCs in Germany implies that assessment of severity of shortages due to a pandemic depends on detailed knowledge about the fraction of transfusions that do not allow for postponement. Pandemic preparedness should include criteria for prioritization of transfusions.
Activity‐based costs of blood transfusions in surgical patients at four hospitals
Authors: Shander Aryeh , Hofmann Axel , Ozawa Sherri , Theusinger Oliver M. , Gombotz Hans , Spahn Donat R.
Published: December 2009

BACKGROUND: Blood utilization has long been suspected to consume more health care resources than previously reported. Incomplete accounting for blood costs has the potential to misdirect programmatic decision making by health care systems. Determining the cost of supplying patients with blood transfusions requires an in‐depth examination of the complex array of activities surrounding the decision to transfuse.

STUDY DESIGN AND METHODS: To accurately determine the cost of blood in a surgical population from a health system perspective, an activity‐based costing (ABC) model was constructed. Tasks and resource consumption (materials, labor, third‐party services, capital) related to blood administration were identified prospectively at two US and two European hospitals. Process frequency (i.e., usage) data were captured retrospectively from each hospital and used to populate the ABC model.

RESULTS: All major process steps, staff, and consumables to provide red blood cell (RBC) transfusions to surgical patients, including usage frequencies, and direct and indirect overhead costs contributed to per‐RBC‐unit costs between $522 and $1183 (mean, $761 ± $294). These exceed previously reported estimates and were 3.2‐ to 4.8‐fold higher than blood product acquisition costs. Annual expenditures on blood and transfusion‐related activities, limited to surgical patients, ranged from $1.62 to $6.03 million per hospital and were largely related to the transfusion rate.

CONCLUSION: Applicable to various hospital practices, the ABC model confirms that blood costs have been underestimated and that they are geographically variable and identifies opportunities for cost containment. Studies to determine whether more stringent control of blood utilization improves health care utilization and quality, and further reduces costs, are warranted.
Recent Caffeine Ingestion Reduces Adenosine Efficacy in the Treatment of Paroxysmal Supraventricular Tachycardia
Authors: Cabalag Miguel S. , Taylor David McDonald , Knott Jonathan C. , Buntine Paul , Smit DeVilliers , Meyer Alastair
Published: December 2009

Objectives: Caffeine, an adenosine receptor blocker, should theoretically reduce adenosine efficacy in the treatment of paroxysmal supraventricular tachycardia (SVT). We aimed to determine the effect of recent caffeine ingestion on the likelihood of reversion of SVT with adenosine.

Methods: This was a multicenter, case–control study of adult patients with SVT treated with adenosine between September 2007 and July 2008. The primary endpoint was reversion to sinus rhythm (SR) after a 6‐mg adenosine bolus, as a function of recent (within 2, 4, 6, and 8 hours) caffeine ingestion. Caffeine ingestion data were collected using a self‐administered questionnaire.

Results: Of 68 patients enrolled, 52 (76.5%, 95% confidence interval [CI] = 64.4% to 85.6%) reverted after a 6‐mg adenosine bolus. There were no significant differences in age, sex, or daily caffeine ingestion between patients who did and did not revert (p > 0.05). However, as a group, patients who did not revert had recently ingested significantly more caffeine (p < 0.05). If caffeine had been ingested less than 2 or 4 hours before the adenosine bolus, the odds of reversion to SR were significantly reduced (odds ratio [OR] = 0.18, 95% CI = 0.04 to 0.93; and OR = 0.14, 95% CI = 0.04 to 0.49, respectively). If caffeine had been ingested less than 6 or 8 hours before the adenosine, the odds of reversion were not reduced (OR = 0.31, 95% CI = 0.09 to 1.02; and OR = 0.31, 95% CI = 0.09 to 1.08, respectively).

Conclusions: Ingestion of caffeine less than 4 hours before a 6‐mg adenosine bolus significantly reduces its effectiveness in the treatment of SVT. An increased initial adenosine dose may be indicated for these patients.

ACADEMIC EMERGENCY MEDICINE 2010; 17:44–49 © 2009 by the Society for Academic Emergency Medicine
Validation of the Wong‐Baker FACES Pain Rating Scale in Pediatric Emergency Department Patients
Authors: Garra Gregory , Singer Adam J. , Taira Breena R. , Chohan Jasmin , Cardoz Hiran , Chisena Ernest , Thode Henry C.
Published: December 2009

Objectives:  The Wong‐Baker FACES Pain Rating Scale (WBS), used in children to rate pain severity, has been validated outside the emergency department (ED), mostly for chronic pain. The authors validated the WBS in children presenting to the ED with pain by identifying a corresponding mean value of the visual analog scale (VAS) for each face of the WBS and determined the relationship between the WBS and VAS. The hypothesis was that the pain severity ratings on the WBS would be highly correlated (Spearman’s rho > 0.80) with those on a VAS.

Methods:  This was a prospective, observational study of children ages 8–17 years with pain presenting to a suburban, academic pediatric ED. Children rated their pain severity on a six‐item ordinal faces scale (WBS) from none to worst and a 100‐mm VAS from least to most. Analysis of variance (ANOVA) was used to compare mean VAS scores across the six ordinal categories. Spearman’s correlation (ρ) was used to measure agreement between the continuous and ordinal scales.

Results:  A total of 120 patients were assessed: the median age was 13 years (interquartile range [IQR] = 10–15 years), 50% were female, 78% were white, and six patients (5%) used a language other than English at home. The most commonly specified locations of pain were extremity (37%), abdomen (19%), and back/neck (11%). The mean VAS increased uniformly across WBS categories in increments of about 17 mm. ANOVA demonstrated significant differences in mean VAS across face groups. Post hoc testing demonstrated that each mean VAS was significantly different from every other mean VAS. Agreement between the WBS and VAS was excellent (ρ = 0.90; 95% confidence interval [CI] = 0.86 to 0.93). There was no association between age, sex, or pain location with either pain score.

Conclusions:  The VAS was found to have an excellent correlation in older children with acute pain in the ED and had a uniformly increasing relationship with WBS. This finding has implications for research on pain management using the WBS as an assessment tool.

ACADEMIC EMERGENCY MEDICINE 2010; 17:50–54 © 2009 by the Society for Academic Emergency Medicine
Perspective Taking and Intergroup Helping Intentions: The Moderating Role of Power Relations1
Authors: Bilewicz Michal
Published: December 2009

People are more willing to help those who belong to their own groups than to an out‐group. Research on perspective taking has shown that many forms of in‐group favoritism disappear when people are led to take the perspective of the other group. The current research explores the possibility of increasing the level of intergroup helping by a perspective‐taking manipulation. An experiment in a Polish‐Czech borderland community high school demonstrated that Polish students who were made to imagine that they became members of an out‐group (perspective‐taking manipulation) were more willing to help out‐group members. The moderating role of perceived power is discussed in the context of perspective‐taking theory.
Proactive People Are Morning People1
Authors: Randler Christoph
Published: December 2009

Proactivity is the willingness and ability to take action to change a situation to one's advantage and has been studied in a wide range of contexts. The role of chronotype on proactivity has not been assessed. Individual differences in circadian rhythms have been widely acknowledged and are accepted as an interesting facet of human personality. Morning people were more proactive than evening types, and people with small differences in rise time between weekdays and free days were also more proactive persons. Sleep length (on weekdays and on free days) and total time spent in weekend oversleep did not show any relationship with proactivity. These results suggest that morning people are more proactive than are evening types.
Analysis of humoral immune responses in rhesus macaques vaccinated with attenuated SIVmac239Δnef and challenged with pathogenic SIVmac251
Authors: Freißmuth Doris , Hiltgartner Alexander , Stahl‐Hennig Christiane , Fuchs Dietmar , Tenner‐Racz Klara , Racz Paul , Überla Klaus , Strasak Alexander , Dierich Manfred P. , Stoiber Heribert , Falkensammer Barbara
Published: December 2009

Background  To determine the correlation between protection and humoral immune response against simian immunodeficiency virus (SIVmac251), 11 macaques were immunized with live‐attenuated SIVmac239Δnef either intravenously or via the tonsils and exposed to SIVmac251 after either 6 or 15 months along with unvaccinated controls.

Results  Independent of the route of vaccine application, viremia was significantly reduced in vaccinees compared with controls 2 weeks post‐challenge. Concomitantly, viremia correlated inversely with SIV‐specific IgG, complement‐mediated lysis and neutralizing antibodies and these parameters seemed to contribute to reduced viremia. During chronic infection, six monkeys controlled viremia in the circulation (two or fewer infectious units per 106 PBMCs) and showed no signs of trapping in lymphatic tissues (Appendix S1).

Conclusions  As no significant differences were observed throughout the study, with respect to the humoral immune response and viremia control, between the two vaccinated cohorts, mucosal immunization strategies are recommended due to more simplified application.
Choices for People With Intellectual Disabilities: Official Discourse and Everyday Practice
Authors: Antaki Charles , Finlay W. M. L. , Walton Chris
Published: December 2009

Official policy talk of “choice” for people with intellectual impairments tends toward fundamental life choices (e.g., who to marry, what job to work at) at the expense of the minor but more frequent concerns of daily living (when to wash, what to eat, where to go in the evening). Statutes and mission statements are unspecific about how any such choices, big or small, are, or should be, offered. They are also silent on the relation of exercising “choices” to institutional imperatives. To examine these particulars the authors undertook an examination of how choice policies are actualized in day‐to‐day activities in two group homes. Data were drawn from a broader ethnographic study of residential services for people with intellectual disabilities serviced by National Health Service Trust in the United Kingdom. Conversation analysis, used to explicate the interactions, showed how staff, although undoubtedly well‐meaning, use the discourse of choice to promote institutional managerial objectives, thus demonstrating a gap between practice and overarching policy theory and recommendations.
Developing an Education Intervention for Staff Supporting Persons With an Intellectual Disability and Advanced Dementia
Authors: Fahey‐McCarthy Elizabeth , McCarron Mary , Connaire Kevin , McCallion Philip
Published: December 2009

Generally, staff working in settings that provide care for adults with intellectual disabilities (ID) have not received specific education with respect to extended care for terminal illnesses or late‐stage dementia. Equally, staff working in specialist palliative care often are not familiar with the unique issues of supporting persons with intellectual disabilities affected by dementia. To understand care concerns with respect to supporting persons with ID and advanced dementia, and to develop, deliver, and evaluate an educational intervention with staff in ID settings and specialist palliative care services, 14 focus group interviews were conducted with staff across six ID services and one specialist palliative care provider in the greater Dublin (Ireland) area. Qualitative descriptive analysis resulted in the emergence of key themes and formed the development of an educational intervention. Pre‐ and posttest questionnaires assessed responses to a pilot delivery of the educational intervention. Formal feedback from staff indicated that the educational intervention was highly valued and addressed key training concerns. They agreed that the training supported “aging in place,” and the preparation for a “good death” including support for staff, peers, and family in their grief and bereavement. An educational intervention in the form of a trainer manual was produced to support cross‐service system in‐service training on issues of addressing advanced dementia in persons with ID.
“Pachyostosis” in aquatic amniotes: a review
Authors: HOUSSAYE Alexandra
Published: December 2009

During the course of amniote evolution, numerous taxa secondarily adapted to an aquatic life. It appears that many of these taxa primitively display “pachyostosis,” an osseous specialization characterized by an increase in bone compactness and/or volume. The term “pachyostosis” is used in morphological and histological descriptions to describe what in fact corresponds to different patterns. The aim of this paper is to present the current state of knowledge relative to this adaptation among aquatic amniotes. All the taxa that have returned to an aquatic environment are listed. Moreover, their degree of adaptation to the marine environment, their life environment, and the nature of their “pachyostotic” pattern, when present, are described. This inventory enables the evaluation of the current quality of the data relative to this specialization and provides an indication of the work that remains to be done. The functional consequences of “pachyostosis,” and notably its importance for buoyancy control in the context of hydrostatic regulation of the body trim, are discussed and opposed to the requirement of improved swimming abilities in the case of a hydrodynamic mode of trim regulation. Questions are posed about the signification of the polymorphism displayed by this specialization between different taxa, different specimens of the same taxon and different bones of the same specimen, and the problem of quantification of pachyostosis is discussed.
Physiological adaptations of small mammals to desert ecosystems
Authors: SCHWIMMER Hagit , HAIM Abraham
Published: December 2009

Adaptations of animals to the xeric environment have been studied in various taxonomic groups and across several deserts. Despite the impressive data that have been accumulated, the focus in most of these studies is mainly on the significance of one variable at a time. Here, we attempt to integrate between responses of several physiological systems, challenged by increasing diet and water salinity and extreme temperatures, acquired in different studies of thermo and osmo‐regulatory adaptations, of small rodents, to the xeric environment. Studies have shown differential thermoregulatory responses to increased dietary salinity, which were attributed to habitat and habits of the relevant species. In the thermoregulatory studies, a potential adaptive significance of low metabolic rate was demonstrated. From an evolutionary point of view, the most important adaptation is in the timing of reproduction, as it enables the transfer of genetic properties to the next generation in an unpredictable ecosystem, where reproduction might not occur every year. Results in this aspect show that increased dietary salinity, through an increase in vasopressin plasma levels, plays an important role as a regulator of the reproductive system. We assume that the amount of food existing in the habitat and the amount of reserves in the animal in the form of white adipose tissue are important for reproduction. Photoperiod affects all studied physiological responses, emphasizing the importance of pre‐acclimation to seasonal characteristics. We summarize the existing data and suggest neuro‐endocrine pathways, which have a central role in these adaptations by affecting thermoregulation, osmoregulation and reproduction to create the optimal response to xeric conditions. These hypotheses can be used as the basis for future studies.
Determination of REE, Y, Nb, Zr, Hf, Ta, Th and U in Geological Reference Materials LSHC‐1 and Amf‐1 by Solution and Laser Ablation ICP‐MS
Authors: Smirnova Elena V. , Flem Belinda , Anchutina Elena A. , Mysovskaya Irina N. , Lozhkin Valeriy I. , Petrov Lev L.
Published: December 2009

This paper presents data on REE and Y, Nb, Zr, Hf, Ta, Th and U abundances for two candidate reference materials (RMs), spinel lherzolite LSHC‐1 and amphibole Amf‐1, being currently developed at the Institute of Geochemistry SB RAS, Irkutsk. To determine the contents of these elements inductively coupled plasma‐mass spectrometry was applied with: (i) solution nebulisation (solution ICP‐MS) and (ii) laser ablation (LA‐ICP‐MS) of fused glass disks. The precision of results obtained by both techniques was better than 6% RSD for most elements. Accuracy was assessed by using the geochemical RMs JB‐2, JGb‐1 (GSJ) and MAG‐1 (USGS). The trace element results by solution ICP‐MS for JGb‐1 and JB‐2 agree with reference values presented by Imai et al. (1995, this Journal) within 1–10%. Significant differences were found for Nb and Ta determinations. The accuracy of LA‐ICP‐MS results evaluated by RM MAG‐1 was within 4%, except for Eu (about 10%). The analytical results obtained for LSHC‐1 and Amf‐1 by solution ICP‐MS and LA‐ICP‐MS were in good agreement with each other and with INAA and XRF data presented for the certification of these RMs. They can be considered as the indicative values for assigning certified values to the above‐mentioned RMs.
Management and survival of patients admitted with an exacerbation of COPD: Comparison of two Danish patient cohorts
Authors: Eriksen Nanna , Vestbo Jørgen
Published: December 2009

Introduction:  The aim of this study was to describe the management and prognosis related to a hospital admission for acute exacerbation of chronic obstructive pulmonary disease and to compare results to an earlier study.

Objectives and Methods:  This is a retrospective study of 300 consecutively discharged patients admitted in 2006–2007 with an exacerbation of chronic obstructive pulmonary disease from three respiratory departments. Data were collected from patient charts and compared with a replicate study done in 2001.

Results:  The mean age was 72.1 years; 61.7% were women. Mean forced expiratory volume in 1 s was 37.6% of predicted. On admission, 11.3% were treated with non‐invasive ventilation, and 84.3% were given systemic corticosteroids. In‐hospital mortality was 4.7%. At discharge, treatment with inhaled corticosteroids or at least one long‐acting bronchodilator was given to 86.7% and 89% of patients, respectively, which was significantly higher than for similarly sampled patients in 2001. Mortality in 30 days and 1 year after discharge was 4.5% and 25.5%, respectively, compared with 5.5% and 30.3% in 2001, the 12‐month mortality being significantly lower (P = 0.03). Readmission rate in the 12 months following discharge was 42.3%. Long‐term oxygen treatment, treatment with anti‐dysrhythmic drugs and lack of outpatient follow‐up were independent predictors of 1‐year mortality. Risk of readmission was increased with dependence in self‐care activities, previous admissions and treatment with strong analgesics.

Conclusions:  Over a period of 6 years, a significantly higher number of patients are being treated according to guidelines. Survival following discharge increased over the same period.

Please cite this paper as: Eriksen N and Vestbo J. Management and survival of patients admitted with an exacerbation of COPD: comparison of two Danish patient cohorts. The Clinical Respiratory Journal 2010; 4: 208–214.
Pneumococcal carriage is more common in asthmatic than in non‐asthmatic young men
Authors: Jounio Ulla , Juvonen Raija , Bloigu Aini , Silvennoinen‐Kassinen Sylvi , Kaijalainen Tarja , Kauma Heikki , Peitso Ari , Saukkoriipi Annika , Vainio Olli , Harju Terttu , Leinonen Maija
Published: December 2009

Introduction:  The aim was to investigate the prevalence of oropharyngeal carriage of Streptococcus pneumoniae, Haemophilus influenzae, Moraxella catarrhalis, Neisseria meningitidis and beta‐haemolytic streptococci among asthmatic and non‐asthmatic young Finnish men and to identify putative risk factors.

Objectives:  A total of 224 asthmatics and 668 non‐asthmatic men (mean age 19.6 years) from two intakes of conscripts to the Kainuu Brigade, Finland in July 2004 and January 2005 were enrolled upon entering military service.

Methods:  Oropharyngeal specimens were examined for bacteria by routine culture methods. All the participants filled in questionnaires concerning risk factors for asthma and respiratory infections.

Results:  S. pneumoniae (48 cases, 5.4%), Group A streptococci (16, 1.8%), H. influenzae (45, 5.0%), M. catarrhalis (24, 2.7%) and N. meningitidis (20, 2.2%) were isolated from the 892 participants. Ten putative risk factors for oropharyngeal colonization (asthma, atopy, allergic rhinitis, smoking, current use of asthma medication, history of adeno/tonsillectomy, level of highly sensitive C‐reactive protein, peak expiratory flow, results of a 12‐min running test and body mass index) were evaluated. The only significant risk factor for S. pneumoniae carriage was asthma (OR, 2.04; 95% CI 1.12 to 3.72).

Conclusions:  Pneumococcal carriage is more common in asthmatic than in non‐asthmatic young men.

Please cite this paper as: Jounio U, Juvonen R, Bloigu A, Silvennoinen‐Kassinen S, Kaijalainen T, Kauma H, Peitso A, Saukkoriipi A, Vainio O, Harju T and Leinonen M. Pneumococcal carriage is more common in asthmatic than in non‐asthmatic young men. The Clinical Respiratory Journal 2010; 4: 222–229.
Processing Defects and Resulting Mechanical Properties After Metal Injection Molding
Authors: Gelin J. C. , Barriere Th. , Song J.
Published: December 2009

The paper is concerned with occurrence of processing defects and resulting mechanical properties associated with material processing by metal injection molding (MIM). MIM process is a multistep one that consists first in the injection of metallic powders mixed with a thermoplastic binder, followed by a debinding stage that permits to evacuate the polymeric binder, and then followed by a sintering stage by solid state diffusion that normally leads to a nearly dense component. The main defects arising during MIM processing are associated with powder segregation during injection molding, and uncompleted or heterogeneous mechanical properties resulting from solid state diffusion. The paper first describes a biphasic fluid flow approach that can accurately predict powder volume fraction after injection molding and consequently the associated segregation defects. This analysis is followed and continued by a proper sintering model based on an elastic-viscous analogy that predicts the resulting local densities after sintering and also associated defects. So, from the two subsequent models, it becomes possible to get the final powder densities after processing and to localize the possible resulting defects. This analysis is completed by an analysis using a porous material model to get the final resultant mechanical properties after processing.
Temperature and Load Ratio Effects on Crack-Growth Behavior of Austenitic Superalloys
Authors: Roy Ajit K. , Pal Joydeep , Hasan Muhammad H.
Published: December 2009

The role of temperature and load ratio (R) on the crack propagation rate (da/dN) of Alloys 276 and 617 under cyclic loading was investigated. The results indicate that the rate of cracking was gradually enhanced with increasing temperature when the R value was kept constant. However, the temperature effect was more pronounced at 100–150°C. Both alloys exhibited maximum da/dN values at a load range of 4.5 kN that corresponds to an R value of 0.1. The number of cycles to failure for Alloy 276 was relatively higher compared with that of Alloy 617, indicating its slower crack-growth rate. Fractographic evaluation of the broken specimen surface revealed combined fatigue and ductile failures.
Determinist-Probabilistic Concept in Modeling Fatigue Damage Through a Micromechanical Approach
Authors: Abdul-Latif A. , Chadli M.
Published: December 2009

Motivated by a micromechanical determinist-probabilistic model coupled with damage recently developed by the authors, a new generalization is proposed to describe the nonlinear elasto-inelastic cyclic strain-stress behavior of polycrystals notably under biaxial cyclic loading paths. In this context, this generalization considers a compressible and linear anisotropic granular elastic strain behavior coupled with damage. The model is expressed in the framework of the time dependent plasticity for a small strain assumption. It is assumed that a damage variable initiates at the mesoscopic (granular) level where the plastic strain localization phenomenon takes place. The associated thermodynamic force of the damage variable is determined using the concept of total granular energy (elastic and inelastic). The transition of the elastic strain from the single to the polycrystal is modified due to its explicit coupling with damage. Comparisons between predicted and experimental results are conducted describing the low-cycle fatigue behavior of the aluminum alloy 2024 under different complex cyclic loading paths. It is demonstrated that the model has a reasonable ability in describing the cyclic behavior of this alloy. Qualitatively, the model is tested under different cyclic loading paths with stress-controlled condition describing especially the ratcheting behavior of the alloy. In fact, the effects of the applied mean stress on the predicted overall elasto-inelastic behavior and on the fatigue life are carefully studied. It shows the dependence of the fatigue life on the mean stress value.
Development of Strong Surfaces Using Functionally Graded Composites Inspired by Natural Teeth—A Theoretical Approach
Authors: Giannakopoulos A. E. , Kordolemis A. , Zisis Th.
Published: December 2009

In recent years functionally-graded composites have been proposed to develop strong surfaces that can withstand high contact and frictional forces. The present work presents a new graded composite that can be used for the development of surfaces with excellent strength properties. The composite is inspired by the human teeth, which nature builds as a hard and tough functionally-graded composite. The outer surface of teeth is of enamel, composed of prismatic hydroxyapatite crystallites, whereas the inner part of teeth is of dentine, composed collagen fibrils and hydroxyapatite. Enamel is hard, brittle, and wear resistant, while dentine is softer and flexible. The dentine-enamel junction is formed as a region at which enamel mixes with dentine in a continuous way. The nanomechanical properties of the transition zone have been recently revealed. Of particular interest in this investigation is the variation in the elastic modulus from the pure enamel to the pure dentine material, which leads to biomimetic graded composites that exhibit high surface strength. This work presents analytical solutions for the stress and displacement fields on an actual composite substrate, which is loaded by a line load. The elastic modulus of the substrate follows approximately the theoretical distribution.
Near-Field Radiation Calculated With an Improved Dielectric Function Model for Doped Silicon
Authors: Basu S. , Lee B. J. , Zhang Z. M.
Published: December 2009

This paper describes a theoretical investigation of near-field radiative heat transfer between doped silicon surfaces separated by a vacuum gap. An improved dielectric function model for heavily doped silicon is employed. The effects of doping level, polarization, and vacuum gap width on the spectral and total radiative transfer are studied based on the fluctuational electrodynamics. It is observed that increasing the doping concentration does not necessarily enhance the energy transfer in the near-field. The energy streamline method is used to model the lateral shift of the energy pathway, which is the trace of the Poynting vectors in the vacuum gap. The local density of states near the emitter is calculated with and without the receiver. The results from this study can help improve the understanding of near-field radiation for applications such as thermophotovoltaic energy conversion, nanoscale thermal imaging, and nanothermal manufacturing.
A Numerical Simulation of Combined Radiation and Natural Convection in a Differential Heated Cubic Cavity
Authors: Kumar P. , Eswaran V.
Published: December 2009

This article presents a numerical simulation of combined radiation and natural convection in a three-dimensional differentially heated rectangular cavity with two opposite side walls kept at a temperature ratio Th/Tc=2.0 and Tc=500 K, with others walls insulated. A non-Boussinesq variable density approach is used to incorporate density changes due to temperature variation. The Navier–Stokes (NSE), temperature, as well as the radiative transfer (RTE) equations are solved numerically by a finite volume method, with constant thermophysical fluid properties (except density) for Rayleigh number Ra=105 and Prandtl number Pr=0.71. The convective, radiative, and total heat transfer on the isothermal and adiabatic walls is studied along with the flow phenomena. The results reveal an extraordinarily complex flow field, wherein, along with the main flow, many secondary flow regions and singular points exist at the different planes and are affected by the optical properties of the fluid. The heat transfer decreases with increase in optical thickness and the pure convection Nusselt number is approached as the optical thickness τ>100, but with substantially different velocity field. The wall emissivity has a strong influence on the heat transfer but the scattering albedo does not.
A Quasidependent Scattering Radiative Properties Model for High Density Fiber Composites
Authors: Lee Siu-Chun
Published: December 2009

This paper presents a theoretical model for the radiative properties of fiber composites fabricated of spatially oriented fiber strands that contain closely spaced fibers in the Mie scattering regime. Dependent scattering within the dense fiber strands is accounted for by utilizing the solution of Maxwell’s equations that included the near field interaction of cylindrical waves. Scattering between strands is shown to be uncorrelated due to their macroscopic dimensions compared with the wavelength of the incident radiation. The model is called quasidependent scattering approximation (QDA), as the radiative properties are formulated as the uncorrelated sum of the dependent scattering properties of the constituent fiber strands. The extinction coefficient, scattering coefficient, and scattering phase function are derived for fiber composites of arbitrary internal architecture. The application of the QDA model is demonstrated by means of numerical analyses on two types of fiber composites.
Heat Transfer Augmentation: Radiative-Convective Heat Transfer in a Tube With Fiber Array Inserts
Authors: Hantsch Andreas , Gross Ulrich , Martin Andrew R.
Published: December 2009

Gas-phase heat transfer plays a critical role in many high temperature applications, such as preheaters, combustors, and other thermal equipment. In such cases common heat transfer augmentation methods rely on the convective component alone to achieve improved internal performance. Radiatively assisted heat transfer augmentation has been suggested as a way to overcome limitations in convective-only enhancement. One example of such a technique is the fiber array insert; thermal radiation emitted by tube walls is captured by a large number of slender fibers, which in turn convect heat to the flowing fluid. Previous numerical studies have indicated that this technique represents a promising enhancement method warranting further investigation. This paper presents results from an experimentally based feasibility study of fiber array inserts for heat transfer augmentation in an externally heated duct. Fibers composed of 140 μm silicon carbide and 150 μm stainless steel were assembled in arrays with porosities around 0.98, and were tested for empty-tube Reynolds numbers ranging from 17,500 to 112,500 and wall temperatures from ambient up to 750°C. The arrays cause a significant pressure drop—roughly two orders of magnitude higher than the empty-tube case—but tube-side heat transfer coefficients were improved by up to 100% over the convective-only case in the low flow rate regime. The stainless steel fiber array exhibited similar heat transfer performance as the silicon carbide case, although pressure drop characteristics differed owing to variations in fluid-structure flow phenomena. Pressure drop data were roughly within the range of d’Arcy law predictions for both arrays, and deviations could be explained by inhomogeneities in fiber-to-fiber spacing. Heat transfer was found to depend nonlinearly on wall temperature and flow rate, in contrast to previously reported numerical data.
A Micromechanical Model to Predict Mechanical Durability of Glass Multifilament Bundles in Rubber Composite
Authors: Ghosh Subrata B. , Bhowmik Deepayan , Hand Russell J. , Jones Frank R.
Published: December 2009

Many rubber products are reinforced with glass fibers to give dimensional stability, high modulus, and good fatigue life. To understand failure of these products, it is essential to understand the failure and strength degradation mechanisms of the reinforcing glass multifilament bundles. An empirical model has been developed to predict fast fracture and time-dependent failure of these bundles using the global load sharing approximation. The model is based on the statistical strength distribution of glass fibers, fracture mechanics of glass, and nonlinear stress distribution between individual fibers owing to sliding resistance of matrix. The model was also used to predict the residual strength of the bundle as a function of load and time.
Densification of Porous Stainless-Steel SLS Components During Cold Isostatic Pressing
Authors: Qingsong Wei , Yanying Du , Bingbing Qu , Yusheng Shi
Published: December 2009

The process that combines selective laser sintering (SLS) and cold isostatic pressing (CIP) can manufacture nearly fully dense metal components with complex geometries. However, the SLS component will shrink to a significant extent during the CIP process. The modified cam-clay model was used to describe the constitutive equation of porous stainless-steel SLS components. The densification process of SLS porous components was simulated using the finite element method. The visual distributions of shape change, displacement, density, and stress were obtained, which showed that SLS components shrank with the same shape as the original design over the CIP process. In addition, a relative uniform density distribution appeared in cold isostatic pressed components. The experiment measurements displayed that the shrinkage rate of SLS components during the CIP process in height direction was a little higher than that on the forming plane due to the layer-by-layer manufacturing process of SLS. On the forming plane, the dimensional errors between simulations and experiments for the cuboid and the gear components are lower than 1% and 3%, respectively. However, the errors in height direction of the two components increase to the range of 6% and 9%.
A Finite Element Treatment of the Angular Dependency of the Even-Parity Equation of Radiative Transfer
Authors: Becker R. , Koch R. , Bauer H.-J. , Modest M. F.
Published: December 2009

The present article introduces a new method to solve the radiative transfer equation (RTE). First, a finite element discretization of the solid angle dependence is derived, wherein the coefficients of the finite element approximation are functions of the spatial coordinates. The angular basis functions are defined according to finite element principles on subdivisions of the octahedron. In a second step, these spatially dependent coefficients are discretized by spatial finite elements. This approach is very attractive, since it provides a concise derivation for approximations of the angular dependence with an arbitrary number of angular nodes. In addition, the usage of high-order angular basis functions is straightforward. In the current paper, the governing equations are first derived independently of the actual angular approximation. Then, the design principles for the angular mesh are discussed and the parameterization of the piecewise angular basis functions is derived. In the following, the method is applied to one-dimensional and two-dimensional test cases, which are commonly used for the validation of approximation methods of the RTE. The results reveal that the proposed method is a promising alternative to the well-established practices like the discrete ordinates method (DOM) and provides highly accurate approximations. A test case, which is known to exhibit the ray effect in the DOM, verifies the ability of the new method to avoid ray effects.