bluuebunny/crossref_metadata_2025 huggingface dataset:
Genetic Deletion of Chemokine Receptor Ccr6 Decreases Atherogenesis in

ApoE

-Deficient Mice
Authors: Wan Wuzhou , Lim Jean K. , Lionakis Michail S. , Rivollier Aymeric , McDermott David H. , Kelsall Brian L. , Farber Joshua M. , Murphy Philip M.
Published: June 2011

Rationale:

The chemokine receptor Ccr6 is a G-protein–coupled receptor expressed on various types of leukocytes identified in mouse atherosclerotic lesions. Recent evidence suggests that both CCR6 and its ligand CCL20 are also present in human atheroma; however, their functional roles in atherogenesis remain undefined.

Objective:

Our objective was to delineate the role of Ccr6 in atherogenesis in the apolipoprotein E–deficient (
ApoE
−/−
) mouse model of atherosclerosis.

Methods and Results:

Both Ccr6 and Ccl20 are expressed in atherosclerotic aorta from
ApoE
−/−
mice. Aortic lesion area in
Ccr6
−/−
ApoE
−/−
mice was ∼40% and ∼30% smaller than in
Ccr6
+/+
ApoE
−/−
mice at 16 and 24 weeks of age, respectively. Transplantation of bone marrow from
Ccr6
−/−
mice into
ApoE
−/−
mice resulted in ∼40% less atherosclerotic lesion area than for bone marrow from
Ccr6
+/+
mice; lesions in
Ccr6
−/−
ApoE
−/−
mice had 44% less macrophage content than lesions in
Ccr6
+/+
ApoE
−/−
mice. Ccr6 was expressed on a subset of primary mouse monocytes. Accordingly, Ccl20 induced chemotaxis of primary monocytes from wild-type but not
Ccr6
−/−
mice; moreover, Ccl20 induced monocytosis in
ApoE
−/−
mice in vivo. Consistent with this, we observed 30% fewer monocytes in circulating blood of
Ccr6
−/−
ApoE
−/−
mice, mainly because of fewer CD11b
+
Ly6C
high
inflammatory monocytes.

Conclusions:

Ccr6 promotes atherosclerosis in
ApoE-
deficient mice, which may be due in part to Ccr6 support of normal monocyte levels in blood, as well as direct Ccr6-dependent monocyte migration.
Does Treatment of Ruptured Intracranial Aneurysms Within 24 Hours Improve Clinical Outcome?
Authors: Phillips Timothy J. , Dowling Richard J. , Yan Bernard , Laidlaw John D. , Mitchell Peter J.
Published: June 2011

Background and Purpose—

The purpose of this study was to analyze whether treating ruptured intracranial aneurysms within 24 hours of subarachnoid hemorrhage improves clinical outcome.

Methods—

An 11-year database of consecutive ruptured intracranial aneurysms treated with endovascular coiling or craniotomy and clipping was analyzed. Outcome was measured by the modified Rankin Scale at 6 months. Our policy is to treat all cases within 24 hours of subarachnoid hemorrhage. Treatment delays are due to nonclinical logistical factors.

Results—

Two hundred thirty cases were coiled or clipped within 24 hours of subarachnoid hemorrhage and 229 at >24 hours. No difference in age, gender, smoking, family history of subarachnoid hemorrhage, aneurysm size, or aneurysm location was found between the groups. Poor World Federation of Neurological Surgeons clinical grade patients were overrepresented in the ultra-early group. Increasing age and higher World Federation of Neurological Surgeons clinical grade were predictors of poor outcome. Eight point zero percent of cases treated within 24 hours of subarachnoid hemorrhage (ultra-early) were dependent or dead at 6 months compared with 14.4% of those treated at >24 hours (delayed), a 44.0% relative risk reduction and a 6.4% absolute risk reduction (χ

2

,
P
=0.044). A total of 3.5% of cases coiled within 24 hours were dependent or dead at 6 months compared with 12.5% of cases coiled at 1 to 3 days, an 82% relative risk reduction and a 10.2% absolute risk reduction (χ
2
,
P
=0.040). These groups did not differ in age, World Federation of Neurological Surgeons clinical grade, aneurysm size, or aneurysm location.

Conclusions—

Treatment of ruptured aneurysms within 24 hours is associated with improved clinical outcomes compared with treatment at >24 hours. The benefit is more pronounced for coiling than clipping.
Antibodies Preventing the Interaction of Tissue-Type Plasminogen Activator With N-Methyl-
d
-Aspartate Receptors Reduce Stroke Damages and Extend the Therapeutic Window of Thrombolysis
Authors: Macrez Richard , Obiang Pauline , Gauberti Maxime , Roussel Benoit , Baron Amandine , Parcq Jérôme , Cassé Frédéric , Hommet Yannick , Orset Cyrille , Agin Véronique , Bezin Laurent , Berrocoso Teresa Garcia , Petersen Karl Uwe , Montaner Joan , Maubert Eric , Vivien Denis , Ali Carine
Published: June 2011

Background and Purpose—

Tissue-type plasminogen activator (tPA) is the only drug approved for the acute treatment of ischemic stroke but with two faces in the disease: beneficial fibrinolysis in the vasculature and damaging effects on the neurovascular unit and brain parenchyma. To improve this profile, we developed a novel strategy, relying on antibodies targeting the proneurotoxic effects of tPA.

Methods—

After production and characterization of antibodies (αATD-NR1) that specifically prevent the interaction of tPA with the ATD-NR1 of N-methyl-
d
-aspartate receptors, we have evaluated their efficacy in a model of murine thromboembolic stroke with or without recombinant tPA-induced reperfusion, coupled to MRI, near-infrared fluorescence imaging, and behavior assessments.

Results—

In vitro, αATD-NR1 prevented the proexcitotoxic effect of tPA without altering N-methyl-
d
-aspartate-induced neurotransmission. In vivo, after a single administration alone or with late recombinant tPA-induced thrombolysis, antibodies dramatically reduced brain injuries and blood–brain barrier leakage, thus improving long-term neurological outcome.

Conclusions—

Our strategy limits ischemic damages and extends the therapeutic window of tPA-driven thrombolysis. Thus, the prospect of this immunotherapy is an extension of the range of treatable patients.
Optik-É AN-30 Aircraft Laboratory for Studies of the Atmospheric Composition
Authors: Antokhin Pavel N. , Arshinov Michael Yu , Belan Boris D. , Davydov Denis K. , Zhidovkin Eugenii V. , Ivlev Georgii A. , Kozlov Artiom V. , Kozlov Valerii S. , Panchenko Michael V. , Penner Ioganes E. , Pestunov Dimitrii A. , Simonenkov Denis V. , Tolmachev Gennadii N. , Fofonov Alexander V. , Shamanaev Vitalii S. , Shmargunov Vladimir P.
Published: June 2011

The scientific instrumental complex of the Optik-É AN-30 aircraft laboratory developed at the Institute of Atmospheric Optics of the Siberian Branch of the Russian Academy of Sciences is described in detail. Specifications of the main units of the instrumental complex are presented. Special attention is given to the metrological support of measurements of the atmospheric parameters. Experimental capabilities of the aircraft laboratory are illustrated by the results obtained in recent flights over various regions of the Russian Federation.
Working with volunteers in victim support: Mirror or camouflage?
Authors: Roose Rudi , Verschelden Griet , Vettenburg Nicole , Vanthuyne Tine
Published: June 2011

We address the role of volunteers in victim support in regard to the growing issue of specialization. We argue for a generic basis of victim services and that working with volunteers and professionals holds chances and pitfalls. Volunteers can function as camouflage or as a mirror for professional social work.
The Effects of Corporation- and Industry-Level Strain and Opportunity on Corporate Crime
Authors: Wang Xia , Holtfreter Kristy
Published: June 2011

Although recent corporate crime studies have made important advances by investigating how individuals decide to offend, they have paid limited attention to a corporation’s organizational structures. Yet, the extant organizational studies have generated inconclusive evidence when assessing the relationship between financial performance and corporate crime, and few studies have combined organizational and industrial factors in models of corporate crime. Building on strain and opportunity theories and prior research, the authors develop hypotheses about the direct and interactive effects of corporation- and industry-level strains and opportunity structures. The authors test these hypotheses using Clinard and Yeager’s Illegal Corporate Behavior data. In short, the results indicate that the effect of corporation-level strain is more pronounced for corporations marked by lower levels of diversification and corporations that operate in industries experiencing higher levels of strain. The authors discuss the implications of the findings for theory, research, and policy.
Count Us In: The Experiences of Female War, Peacemaking, and Peacekeeping Veterans
Authors: Feldman Susan , Hanlon Clare
Published: June 2011

This article reports the findings of a qualitative study that explores the linkages between female veterans’ experiences in warlike, peacemaking, peacekeeping, and humanitarian operations and their perceived health support needs over the long term. It is based on the experiences of Australian female veterans who had deployed overseas. The findings suggest that a woman’s emotional well-being over the long term and ability to fully reintegrate back into civilian life after deployment is diminished when there is a significant disparity between her expectations of deployment and her actual operational experiences. A major implication from these findings is that civilian health and support services should develop a better understanding of the distinctive needs of the female veteran population and develop stronger linkages with the military community so as to facilitate ongoing deployment-related support for female veterans.
Regimes, constituencies and the politics of state formation: Zimbabwe and Botswana compared
Authors: Eriksen Stein Sundstøl
Published: June 2011

This article analyses state formation in Botswana and Rhodesia/Zimbabwe in the light of general theories of state formation. It seeks to explain why Botswana became a strong state, while state power in Rhodesia/Zimbabwe has eroded. Three main arguments are made. First, Zimbabwe’s experience shows that security threats and compulsion to collect revenue are not sufficient conditions for establishing a strong state. Second, the Botswana case indicates that the formation of a strong state may be possible even in the absence of such compulsions. Third, both cases reveal that patterns of state formation ultimately depend on the interests of ruling regimes, and on their ability to promote those interests. The creation of a strong state requires that regimes must have an interest in a strong state as well as the power to carry out a project of state building. This depends on the relationship between regimes and their constituencies. The article concludes by pointing out the need for expanding the framework described by security-based and fiscal theories, to include considerations about how state formation is related to the underlying social forces on which state power is based.
How ethnic are African parties really? Evidence from four Francophone countries
Authors: Basedau Matthias , Stroh Alexander
Published: June 2011

Though African party systems are said to be ethnic, there is little evidence for this claim. The few empirical studies rarely rely on individual data and are biased in favour of Anglophone Africa. This paper looks at four Francophone countries, drawing on representative survey polls. Results reveal that ethnicity matters, but that its impact is generally rather weak and differs with regard to party systems and individual parties. ‘Ethnic parties’ in the strict sense are virtually absent. In particular, the voters’ location seems more important than ethnic affiliation. Other determinants such as regional ties, elite strategies, cross-cutting cleavages, and rational preferences deserve more attention in the future study of voting behaviour in Africa.
HIV-Positive Mothers’ Communication About Safer Sex and STD Prevention With Their Children
Authors: Murphy Debra A. , Roberts Kathleen Johnston , Herbeck Diane M.
Published: June 2011

Mothers play an important role in promoting the sexual health of their adolescent children. Fifty-seven HIV-positive mothers with adolescent children participated in an in-depth, qualitative interview regarding whether they have talked to their children about safer sex and sexually transmitted disease (STD) prevention, including at what age they began such discussions and what messages they gave to their children. The majority of mothers (95%) had talked with their child about safer sex; some began such discussions when the children were as young as 6 years old, but most began when the children were around 12 years old. Mothers’ messages fell into the following areas: (a) protecting oneself from STDs; (b) giving factual information regarding STDs, including HIV; (c) avoiding pregnancy; (d) empowering and respecting oneself; and (e) communicating with sexual partners. The mothers’ own HIV status affected the discussions with their children. Content of mothers’ messages, child reactions, and child outcomes are discussed.
Factors associated with perceived barriers to pediatric palliative care: a survey of pediatricians in Florida and California
Authors: Knapp Caprice , Thompson Lindsay
Published: June 2011

Purpose: The provision and uptake of pediatric palliative care continues to be plagued by barriers. Several studies have documented these barriers, but none have done so with a diverse sample (most are at a single institution) or specifically about pediatric palliative care. Moreover, none have investigated the factors associated with perceived barriers. Our study has two aims: (1) to describe the barriers to pediatric palliative care as reported by a group of pediatricians practicing in two large States in the US; and (2) to identify factors associated with these perceived barriers.

Methods: Cross-sectional survey data were collected from 303 pediatricians in Florida and California.

Results: The two greatest barriers reported by the pediatricians were related to families’ reluctance to accept palliative care (95%) and families viewing palliative care as giving up (94%). Only 42% of pediatricians noted that reimbursement was a barrier. Across all the regressions, three factors were consistently associated with barriers to palliative care: race/ethnicity of pediatrician practice setting, and the percentage of low-income patients.

Conclusions: Our findings can be used to develop targeted educational interventions towards providers and families. Understanding the factors that are driving the low uptake in palliative care is the first step in advancing pediatric palliative care overall.
Effect of Intervention With the Self-Determined Learning Model of Instruction on Access and Goal Attainment
Authors: Shogren Karrie A. , Palmer Susan B. , Wehmeyer Michael L. , Williams-Diehm Kendra , Little Todd D.
Published: June 2011

Promoting self-determination has been identified as best practice in special education and transition services and as a means to promote goal attainment and access to the general education curriculum for students with disabilities. There have been, however, limited evaluations of the effects of interventions to promote self-determination on outcomes related to access to the general education curriculum. This article reports findings from a cluster or group-randomized trial control group study examining the impact of intervention using the Self-Determined Learning Model of Instruction on students’ academic and transition goal attainment and on access to the general education curriculum for students with intellectual disability and learning disabilities. Findings support the efficacy of the model for both goal attainment and access to the general education curriculum, though students varied in the patterns of goal attainment as a function of type of disability.
Review paper: Progress in the Field of Conducting Polymers for Tissue Engineering Applications
Authors: Bendrea Anca-Dana , Cianga Luminita , Cianga Ioan
Published: June 2011

This review focuses on one of the most exciting applications area of conjugated conducting polymers, which is tissue engineering. Strategies used for the biocompatibility improvement of this class of polymers (including biomolecules’ entrapment or covalent grafting) and also the integrated novel technologies for smart scaffolds generation such as micropatterning, electrospinning, self-assembling are emphasized. These processing alternatives afford the electroconducting polymers nanostructures, the most appropriate forms of the materials that closely mimic the critical features of the natural extracellular matrix. Due to their capability to electronically control a range of physical and chemical properties, conducting polymers such as polyaniline, polypyrrole, and polythiophene and/or their derivatives and composites provide compatible substrates which promote cell growth, adhesion, and proliferation at the polymer—tissue interface through electrical stimulation. The activities of different types of cells on these materials are also presented in detail. Specific cell responses depend on polymers surface characteristics like roughness, surface free energy, topography, chemistry, charge, and other properties as electrical conductivity or mechanical actuation, which depend on the employed synthesis conditions. The biological functions of cells can be dramatically enhanced by biomaterials with controlled organizations at the nanometer scale and in the case of conducting polymers, by the electrical stimulation. The advantages of using biocompatible nanostructures of conducting polymers (nanofibers, nanotubes, nanoparticles, and nanofilaments) in tissue engineering are also highlighted.
Fabrication of oxidized alginate-gelatin-BCP hydrogels and evaluation of the microstructure, material properties and biocompatibility for bone tissue regeneration
Authors: Nguyen Thi-Phuong , Lee Byong-Taek
Published: June 2011

Composite hydrogel systems consisting of oxidized alginate, gelatin, and biphasic calcium phosphate were fabricated by the Schiff-base reaction and the effect of oxidation of alginate on the microstructure, material properties, and biocompatibility were evaluated. Alginate was modified by oxidizing the attached −OH groups to a −CHO group to facilitate interactions with the −NH2 groups of gelatin. The increased interactions between the functional groups had several effects on the materials properties, physical behaviors, and bio-compatibility. A higher degree of oxidation and thereby a higher extent of crosslinking between the −CHO and −NH2 groups resulted in an increase in water uptake and compressive strength, which was associated with a decrease in porosity, gelation time, bio-degradation rate, and to a smaller degree, biocompatibility. The hydrogel structure was highly porous and showed unique channel zed morphology with an extensive branching of the channels. The channels were not continuous and were divided into multiple segments by thin separators that were 5 µm thick and branched off of the 10–25 µm thick frame. The pores in the hydrogel system were interconnected and the porosity ranged from 44.45 to 67.89% with a pore size ranging from 100 to 300 µm. The compressive stress failure of the wet hydrogel was at 12.0 ± 1.2 MPa when the degree of alginate oxidation was 66.6%. The biocompatibility of the hydrogel system was excellent, although it was slightly lowered by oxidation. These hydrogels are promising biomaterials for bone regeneration with adjustable gelation and bio-degradation time, good mechanical strength, and excellent bio-compatibility.
A semianalytical and numerical study of penetration and perforation of an ogive-nose projectile into concrete targets under normal impact
Authors: Seifoori S , Liaghat G H
Published: June 2011

In this article, a semianalytical model is proposed to predict the penetration depth of an ogive-nose projectile into a concrete target. In addition, the theory of shear plugging is used to calculate the residual velocity of the projectile following complete perforation of the target. In this analysis, which is based on the Forrestal model, conservation of energy was employed to determine the axial forces on the projectile and target during both the penetration and perforation stages and the governing equations were derived in each case. The tests were then simulated numerically with the finite element code LS-DYNA and good agreement was obtained with both experimental data and the predictions of the analytical model.
Comparison between Wigner–Ville distribution- and empirical mode decomposition vibration-based techniques for helical gearbox monitoring
Authors: Ibrahim G R , Albarbar A
Published: June 2011

This article presents a comparison between empirical mode decomposition (EMD) and smoothed pseudo-Wigner–Ville distribution (SPWVD) methods based on vibration signature and energy calculation procedure for monitoring gearbox systems. The simulation and experimental work were carried out using two-stage helical gears for a healthy pair of gears and a pair suffering from a tooth breakage with severity fault 1 (25 per cent tooth removal), fault 2 (50 per cent tooth removal), fault 3 (75 per cent tooth removal), and fault 4 (100 per cent tooth removal) under loads (0, 20, 40, 60, and 80 per cent of the total load) and speeds (10, 30, 50, 70, and 90 per cent of full speed). This article illustrates that the calculation of energy using EMD techniques offers a more effective way to detect early faults than that computations using the SPWVD method, and that the computation of energy using the EMD technique is faster than the calculations done using the SPWVD method.
Effect of intake hydrogen addition on performance and emission characteristics of a diesel engine with exhaust gas recirculation
Authors: Qian Y J , Zuo C J , Tan J , Xu H M
Published: June 2011

This article presents the potential of improving engine performance and pollutant emissions of a ZS195 Diesel engine by exhaust gas recirculation (EGR) and intake hydrogen enrichment. The effect of EGR level and hydrogen addition on the engine performance and pollutant emissions has been investigated through detailed experiments at rated speed. The experimental results have shown that when EGR level is constant, the peak pressure and maximum rate of pressure rise increase with the increase of hydrogen addition. The intake hydrogen enrichment can reduce HC, CO, and soot level and increase NOX emission, but EGR technique can offset this effect. The combustion speed and thermal efficiency increase with the increase of hydrogen addition when EGR technique has been adopted.
An incremental-update formulation to simulate earing behaviour with crystal plasticity model
Authors: Zhang S , Huang S , Li D , Peng Y
Published: June 2011

To gain a better understanding about the influence of initial texture on deformation behaviour of sheet metals, an incremental-update formulation is adopted for implementing rate-dependent crystal plasticity model into the explicit finite element package, ABAQUS/Explicit. In this formulation, the configuration in the last increment serves as a reference frame, and the stress, grain orientation and hardening behaviour of crystal are updated at the end of each increment. Two user subroutines VUMAT are developed, respectively, for face-centred cubic and hexagonal close packed alloys due to different deformation mechanisms. Earing behaviours of aluminium sheet and AZ31 alloy sheet are simulated for model validation.
Methodology for obtaining C3 continuity on tool trajectory featuring acceleration and jerk constraint on computer numerical control machine
Authors: Rivera-Guillen J R , Romero-Troncoso R J , Osornio-Rios R A , Domínguez-González A
Published: June 2011

High-quality material manufacture requires the improvement of the computer numerical control (CNC) machine performance. Such task can be achieved by considering the tool trajectory, in which it is important to minimize the acceleration and jerk levels. Previous research works are focused on providing smooth movements at most with C2 continuous trajectories, and the results of using C3 continuity in the trajectory are not evaluated. The contribution of this study is the design of a methodology for obtaining C3 tool trajectories while acceleration and jerk levels are constrained through adaptive feed-rate. C3 and C2 trajectories are executed in a CNC machine. Speed, acceleration, and jerk are monitored in order to validate the proposed methodology and to analyse and quantify the differences between using C2 and using C3 trajectories.
A possible origin of surface cracks in rails
Authors: Fischer F D , Daves W
Published: June 2011

The deformation and stress state due to overrolling near the rough surface of a rail is studied. Then a criterion for the inclination of a shear localization zone (SLZ) is introduced. Furthermore, the recent finding that the crack tip driving forces becomes infinite for a crack embedded in a SLZ is recalled. Experimental observation shows also that the fracture toughness in the SLZ is significantly reduced. All these facts point to the development of a crack, the so-called head check if it arises in a regular pattern, in the SLZ, whose predicted direction agrees well with observations.
Performance of a semi-automated approach for risk estimation using a common data model for longitudinal healthcare databases
Authors: Van Le Hoa , Beach Kathleen J , Powell Gregory , Pattishall Ed , Ryan Patrick , Mera Robertino M
Published: June 2011

Different structures and coding schemes may limit rapid evaluation of a large pool of potential drug safety signals using multiple longitudinal healthcare databases. To overcome this restriction, a semi-automated approach utilising common data model (CDM) and robust pharmacoepidemiologic methods was developed; however, its performance needed to be evaluated. Twenty-three established drug-safety associations from publications were reproduced in a healthcare claims database and four of these were also repeated in electronic health records. Concordance and discrepancy of pairwise estimates were assessed between the results derived from the publication and results from this approach. For all 27 pairs, an observed agreement between the published results and the results from the semi-automated approach was greater than 85% and Kappa coefficient was 0.61, 95% CI: 0.19–1.00. Ln(IRR) differed by less than 50% for 13/27 pairs, and the IRR varied less than 2-fold for 19/27 pairs. Reproducibility based on the intra-class correlation coefficient was 0.54. Most covariates (>90%) in the publications were available for inclusion in the models. Once the study populations and inclusion/exclusion criteria were obtained from the literature, the analysis was able to be completed in 2–8 h. The semi-automated methodology using a CDM produced consistent risk estimates compared to the published findings for most selected drug-outcome associations, regardless of original study designs, databases, medications and outcomes. Further assessment of this approach is useful to understand its roles, strengths and limitations in rapidly evaluating safety signals.
Deconstructing civil wars
Authors: Mundy Jacob
Published: June 2011

The identification of intra-national armed conflict as a leading problem for the international community in the 1990s produced a wave of novel research into civil wars. Though these new civil war studies soon began to claim a degree of consensus on several key questions, the very concept and ontology of civil war has been implicitly and explicitly contested. An examination of the politics of naming civil wars likewise reveals the extent to which varying and sometimes conflicting definitions of civil war are still in circulation among various observer types. Instead of adjudicating these disputed definitions of civil war, this article details the way in which particular conceptions of civil war produce their object of analysis. The recent Algerian conflict stands as an excellent case study in the politics of naming civil wars and the ways in which the conceptual frameworks of the new civil war studies make Algeria into a civil war. To go beyond the contested definition of civil war, the new civil war studies should not judge the viability of concepts of mass armed violence – whether civil war or so-called new wars – on their alleged coherence with particular representations of history. Concepts of mass violence should instead be judged in relation to the political goals from which they obtain their warrant in the first place.
Therapist Effects on Disparities Experienced by Minorities Receiving Services for Mental Illness
Authors: Larrison Christopher R. , Schoppelrey Susan L.
Published: June 2011

Objectives: The authors examine if some of the reason clients from racial and ethnic minority groups experience outcome disparities is explained by their therapists. Method: Data from 98 clients (19% minority) and 14 therapists at two community mental health agencies where clients from racial and ethnic minority groups were experiencing outcome disparities were analyzed using hierarchical linear modeling with treatment outcomes at Level 1, client factors at Level 2, and therapists at Level 3. Results: There were substantial therapist effects that moderated the relationship between clients' race and treatment outcomes (outcome disparities). Therapists accounted for 28.7% of the variability in outcome disparities. Conclusions: Therapists are linked to outcome disparities and appear to play a substantial role in why disparities occur.
Bringing the President Back In
Authors: Holbrook Thomas M. , Clouse Clayton , Weinschenk Aaron C.
Published: June 2011

Despite prevailing negative conditions, initial analyses of the 2008 presidential election, including this one, find significant but not particularly strong economic voting effects during the fall campaign. In this article, the authors pay special attention to how the economic information context changed during the campaign and how those changes affected the evolution of retrospective voting. The findings show that there were two distinct phases of the fall campaign, that retrospective voting was nonexistent prior to the collapse of Lehman Brothers but was strong following the collapse. In effect, the collapse of Lehman Brothers turned the election into a referendum election.
The Effect of Racial Group Consciousness on the Political Participation of African Americans and Black Ethnics in Miami-Dade County, Florida
Authors: Austin Sharon D. Wright , Middleton Richard T. , Yon Rachel
Published: June 2011

This research examines group consciousness among people of African descent in Miami-Dade County, Florida, and its possible impact on their political participation. Using an original survey of over one thousand respondents, the authors question whether African Americans and black ethnics (Africans, Afro-Caribbean Americans, Afro-Cuban Americans, and Haitians) possess a shared group consciousness and, if so, why. Second, does group consciousness or socioeconomic status most influence the political participation of our respondents? The authors find that these groups have a common consciousness because of their skin color, experiences with discrimination, common interests, similar ideological views, and leadership preferences. They also find that while group consciousness has more of an impact on African American political participation, socioeconomic status more heavily influences black ethnics. Last, factors such as age, gender, partisanship, religion, and second-generation citizenship also affect African American and/or black ethnic political participation.
Differences Between Internists and Family Practitioners in the Diagnosis and Management of the Same Patient With Coronary Heart Disease
Authors: Shackelton-Piccolo Rebecca , McKinlay John B. , Marceau Lisa D. , Goroll Allan H. , Link Carol L.
Published: June 2011

It has been suggested that internists and family practitioners have somewhat different “disease” perspectives, which may be generated by use of different explanatory models during medical training (pathophysiological vs. biopsychosocial, respectively). This article explores differences between internists and family practitioners in their suggested diagnoses, level of diagnostic certainty, test and prescription ordering, when encountering exactly the same “patient” with coronary heart disease (CHD). Internists were more certain of a CHD diagnosis than family practitioners and were more likely to act on this diagnosis. Family practitioners were more likely to diagnose (and were more certain of) a mental health condition. While many physicians simultaneously entertain several alternate diagnoses, diagnostic certainty has shown to have an important influence on subsequent clinical actions, such as stress testing and prescription of beta blockers. These results may inform future educational strategies designed to reduce diagnostic uncertainty in the face of life-threatening conditions, such as CHD.
Behavior Support Interventions Implemented by Families of Young Children
Authors: McLaughlin Tara W. , Denney Maria K. , Snyder Patricia A. , Welsh Jill L.
Published: June 2011

Families are increasingly involved in the implementation of behavior support interventions to promote positive behaviors of young children in everyday family settings. Contextual fit, described as congruence between the behavior support intervention and the values, skills, resources, and routines of those who will implement the intervention, has been associated with the effectiveness and sustainability of the intervention. We analyzed studies published in the Journal of Positive Behavior Interventions from 1999 to 2009 in which families of young children ages 3 through 8 years implemented behavior support interventions. As part of this review, we examined information reported about contextual fit. Eighteen studies met the inclusion criteria and were coded using an investigator-developed protocol. Findings revealed that researchers generally reported information about collaborative partnerships with families. Information about family ecology, cultural and linguistic background, family perspectives about the intervention, and family quality of life were not reported in the majority of studies reviewed. Recommendations related to future reporting practices and research focused on contextual fit are discussed.
A semi-deterministic texture-roughness model of the piston ring–cylinder liner contact
Authors: Spencer A , Almqvist A , Larsson R
Published: June 2011

Many simulations already exist to model the piston ring–cylinder liner contact; however, very few models have been used to investigate the optimum surface texture. An axi-symmetric, time-dependent two-dimensional semi-deterministic texture-roughness model of the piston ring to cylinder liner contact with periodic boundary conditions and mass preserving global cavitation has been developed. The cylinder liner texture, generated by honing, was considered deterministically on the global scale, after an investigation comparing deterministic and homogenized solutions.

The surface texture of a real cylinder liner was measured with white light interferometry and an algorithm developed to generate an artificial periodic texture representative of the real surface. The effect of cylinder liner plateau roughness has been incorporated on the local scale by homogenization of the Reynolds equation and calculation of flow factors from real surface topography. Using the homogenization technique to incorporate the effect of surface roughness leads to a more efficient solution than mesh refinement of the deterministic problem as the roughness does not need to be resolved on the global solution domain, allowing for significantly less degrees of freedom in the global problem. The lubricant boundary pressures have been calculated using results from a numerical ring-pack model and the lubricant viscosity has been adjusted based on the cylinder liner wall temperature.

It was found from the result of a comparison between deterministic and homogenized solutions that surface texture should be modelled on the global and not on the averaged roughness scale as is the case with many previous investigations.
Influence of oil formulation on gear micropitting and power loss performance
Authors: Martins R C , Seabra J H O , Ruis-Moron L F
Published: June 2011

This study presents a study of the influence of oil formulation on the protection against gear micropitting and also its influence on gear efficiency. The study had both components because a well-balanced product is necessary and its behaviour must be demonstrated in dedicated tests. The industrial gear oils studied combined polyalphaolefin with ester base oils and had different additive packages. FZG gear power loss tests were performed using 20MnCr5 carburized gears under a wide range of operating conditions. During the tests, the oil and gearbox temperature were continuously recorded and gear oil samples were collected. After the tests, the gear mass loss was measured and oil samples were analyzed by ferrography. Using an energetic model of the FZG test gearbox, it was possible to quantify the influence of lubricant formulation on the average friction coefficient between gear teeth, which will provide a quantitative comparison of lubricants. The gear micropitting protection provided by the oxidized lubricant samples was evaluated in a FZG test rig according to DGMK short micropitting test procedure. During the tests, lubricant analysis, mass loss measurements, surface observation, and topography measurements were performed to evaluate the micropitting evolution along the tests as well as severity of micropitting. The results obtained show that the base oil, the additive package, as well as their combination can have a very significant influence on the efficiency and micropitting performance of industrial gear oil.
Investigations into the occurrence of galling during hot forming of Al–Si-coated high-strength steel
Authors: Pelcastre L , Hardell J , Prakash B
Published: June 2011

Galling is a severe form of adhesive wear associated with both cold and hot metal forming operations. In hot sheet metal forming of Al–Si-coated ultrahigh-strength steel (UHSS), transfer occurs from the coated UHSS to the tool surface. This leads to poor quality of produced parts, damage of expensive tooling, and increased downtime for maintenance of the tools. This study thus aims at identifying the salient mechanism(s), which give rise to initiation/occurrence of galling at elevated temperatures. This has been accomplished by analysing actual hot forming tools and through systematic parametric tribological investigations in the laboratory. The analysis of the actual tools has shown that the transferred layer consists of Al, Si, and Fe. The structure of the transferred materials is composed of sintered/compacted wear particles. The parametric study has shown that galling is dependent on the operating conditions. A strong relationship between the contact pressure and material transfer has been observed. The severity of galling is lower for smoother surfaces at low contact pressure. However, at high contact pressure, the influence of roughness under these conditions is insignificant. It has also been observed that hard-tool steel substrates reduce the severity of galling, particularly, at high contact pressure.
Role of friction modifiers on the tribological performance of hypereutectic Al–Si alloy lubricated in boundary conditions
Authors: Morina A , Xia X , Neville A , Priest M , Roshan R , Warrens C P , Payne M J
Published: June 2011

Hypereutectic Al–Si alloys are increasingly being as used as lightweight materials for engine components. This study is focused on understanding the tribochemical performance of a cast iron/Al–Si alloy system lubricated in the boundary regime using lubricating oils containing Zinc Dialkyldithiophosphate (ZDDP) and different friction modifiers. The tribological performance of two organic and two inorganic Mo-containing friction modifiers, blended in a ZDDP-containing oil, is evaluated on a Plint TE 77 reciprocating tribometer in contact conditions comparable to the conditions in a piston ring/cylinder liner system of an internal combustion engine. Surface sensitive analytical techniques such as secondary ion mass spectrometry, X-ray photoelectron spectroscopy, and Raman spectroscopy have been used to determine the chemical nature of the tribofilms formed on the Al–Si material. The additive effects on tribofilm formation as well as tribological performance are discussed.

This study shows that the Mo-containing additives, when blended into a ZDDP-containing lubricant, give superior friction performance when compared to lubricants containing organic friction modifiers. The role of substrate material in tribofilm chemical and physical characteristics for all lubricants is discussed.
Fuel economy in heavy duty diesel engines. Part 1: measurement of oil film thickness on an operating engine
Authors: Smith O , Sutton M
Published: June 2011

Ever increasing pressure to develop engine oils to enhance vehicle fuel economy has resulted in a trend of decreasing finished fluid viscosity. Impressive fuel economy improvements have been yielded through the application of these lower viscosity fluids without compromising component wear, principally due a combination of improvements in engine design, manufacture and additive packages. However, component assemblies such as journal bearings rely on fluid film separation to function effectively. If the viscosity is reduced below a critical value, the component will no longer reside in the fluid film lubrication regimes and will inevitably operate in the regimes of contact. Without radical redesign of the assembly, or advanced lubricant formulation, this will inevitably result in catastrophic engine failure. This article describes the development of an ultrasonic system to measure film thickness in main engine bearings under firing conditions. This unobtrusive method of measuring film thickness in operating contacts has been applied to the main bearings of operating diesel engines. Preliminary measurements were taken during dynamic engine ramping to identify the thinnest operating film condition. Further film measurements were taken at this condition with the engine running on engine oils with varying bulk oil viscosity.
Efficient solution of the dry contact of rough surfaces: a comparison of fast Fourier transform and multigrid methods
Authors: Sainsot P , Lubrecht A A
Published: June 2011

Numerical tools are required to improve our understanding of tribological experiments. In order to represent all the details of rough surface contacts, such calculations require many grid points. Hence, high-performance tools are necessary to obtain precision and limit computing time and memory requirement. This article compares the precision, convergence speed, computing time, memory requirement, and robustness of two solvers for three different cases: a smooth Hertzian contact, a wavy Hertzian contact, and a rough Hertzian contact. The first solver is based around the conjugate gradient method and the deformation integrals are computed using the fast Fourier transform (FFT). The second solver is based on the distributed Gauss–Seidel relaxation, using multigrid (MG) techniques to accelerate convergence and multilevel multi integration (MLMI) for a fast computation of the deformation. The overall conclusion is that the MG method excels in terms of computing speed and memory requirement, whereas the FFT-based code excels in robustness and implementation time.
Tribological performance evaluation of a hydrogenated diamond-like carbon coating in sliding/rolling contact – effect of lubricant additives
Authors: Haque T , Morina A , Neville A
Published: June 2011

In this article, a systematic study is carried out to assess the influence of lubricant additives on the durability of a hydrogenated diamond-like carbon (DLC) coating under mixed rolling/sliding contact is provided. Experiments were performed in a mini traction machine using a DLC (15 at.% hydrogen) coated disc on an uncoated steel ball at 50 per cent sliding/rolling ratio and in a motorized cylinder head (Ford Zetec) cam/follower test rig. Five different lubricants containing zinc dialkyldithiophosphate (ZDDP) and/or friction modifiers (Moly Dimer (MD)/Moly Trimer (MT)) were used. This study reveals that the lubricant additives have a strong influence on the coating durability while ZDDP additive effectively reduces wear to extremely low levels. The addition of the MT additives only has a marginal effect on wear, whereas the MD additive substantially reduces the performance. The mechanisms by which the additives affect the wear in this ultralow-wear regime are discussed.
Experimental evidence of cavitational effects in a Rayleigh step slider
Authors: Pascovici M D , Predescu A , Cicone T , Popescu C S
Published: June 2011

The objective of this article is the study of the load-carrying capacity of a Rayleigh step slider (RSS) for both direct motion (+RSS – which generates lifting effects) and reverse motion (−RSS – which generates suction or cavitational effects). Normal force was measured on a pin-on-disc test rig, with two lubricants (SAE-20 W-50 oil and glycerin) at four speeds and three values of film thickness. During reverse motion (−RSS), cavitational effects have been observed for some test cases. It is supposed that surface tension influences the appearance of cavitational effects, and a modified capillary number, Ca+, is proposed as indicator of cavitation inception. Close-up views taken near the trailing edge of the pin show the occurrence of several streamers, typical for cavitational effects, only when Ca+ > 2. Numerical simulation as well as approximate analytical models are presented for both directions of motion. The comparison of predicted theoretical results with the experimental data is satisfactory.
Sex differences in parental reaction to pediatric illness
Authors: Tifferet Sigal , Manor Orly , Constantini Shlomi , Friedman Orna , Elizur Yoel
Published: June 2011

The ‘Tend-and Befriend’ hypothesis claims that whereas the response of males to stress is Fight-or-Flight, females respond with Tend-and-Befriend. We tested this hypothesis with a sample of 110 couples whose children had undergone neurosurgery. Both mothers and fathers answered questionnaires measuring levels of tending, befriending, stress, anxiety, and depression. As hypothesized, mothers scored higher than fathers did on all measures. However, according to the Tend-and Befriend hypothesis, the sex difference in tending and befriending should be more pronounced in couples suffering from high-stress in comparison to couples suffering from low-stress. This hypothesis was not supported by the data. We suggest that the heightened tending and befriending of women is not a reaction to stress, instead it is a persistent maternal characteristic. Moreover, we suggest that maternal anxiety and depression result from a heightened maternal sensitivity, selected for caregiving. The study results imply that support interventions should be aimed mostly at mothers, since they experience more distress, in comparison to fathers.
Building a Blog Cabin during a Financial Crisis
Authors: Gehl Robert W. , Gibson Timothy A.
Published: June 2011

In their studies of online media, political economists of communication have examined how firms like Google enclose users in a web of commercial surveillance, thus facilitating the commodification of their online labor. However, this focus on enclosure tends to overlook the political possibilities highlighted by autonomist Marxist theory—namely, that users, under certain circumstances, can appropriate these applications to contest conditions of exploitation. This article offers an analysis of Blog Cabin 2008, a cable home improvement show, in order to explore this tension between autonomy and enclosure. Our findings suggest that producers indeed used the show’s blog to exploit fans’ free labor. However, fans also used the blog to form social bonds, to press demands on the show’s producers, and to make connections between the show’s class politics and the wider financial crisis. A concluding section explores the theoretical and political significance of such unanticipated uses of the show’s blog.