bluuebunny/crossref_metadata_2025 huggingface dataset:
Deposition of nanometer scaled calcium‐phosphate crystals to implants with a dual acid‐etched surface does not improve early tissue integration
Authors: Abrahamsson Ingemar , Linder Elena , Larsson Lena , Berglundh Tord
Published: February 2012

Objective

To evaluate hard and soft tissue healing to implants with a dual acid‐etched surface with and without deposition of calcium‐phosphate crystals.

Materials and methods

Three months after extraction of mandibular premolars in six Labrador dogs, four osteotomy preparations, 8 mm deep and 3 mm wide, were performed. The prepared canals were widened in the marginal 4 mm zone to 3.74 mm. Implants with an 8 mm long and 3.75 mm wide intraosseous portion and a 5.0 mm high and 4.0 mm wide transmucosal part were placed in such a way that the base of the wider neck‐portion of the implant coincided with the crestal bone. The implants were dual acid – etched (Osseotite®; Biomet 3i). The surface of the test implants was, in addition, modified by a discrete deposition of calcium‐phosphate crystals (Nanotite™; Biomet 3i). Every second implant placed was a test unit. After 2 weeks the implant installation procedure was repeated in the opposite side of the mandible. Two weeks later the animals were euthanized and biopsies were obtained and prepared for histological analysis.

Results

The degree of bone‐to implant contact (BIC%) was larger at implants without (Osseotite) than in those with (Nanotite) calcium‐phosphate crystals. No differences were found regarding soft tissue dimensions and composition between the two types of implants.

Conclusion

It is suggested that deposition of nanometer‐sized calcium‐phosphate crystals to implants with a dual acid‐etched surface does not improve early tissue integration.
Effects of a single topical doxycycline administration adjunctive to mechanical debridement in patients with persistent/recurrent periodontitis but acceptable oral hygiene during supportive periodontal therapy
Authors: Tonetti Maurizio S. , Lang Niklaus P. , Cortellini Pierpaolo , Suvan Jean E. , Eickholz Peter , Fourmousis Ioannis , Topoll Heinz , Vangsted Tine , Wallkamm Beat
Published: February 2012

Objectives

To evaluate the efficacy of a slow release doxycycline gel (SRD) adjunctively administered to non‐surgical therapy in subjects with recurrent or persistent periodontitis but acceptable oral hygiene during supportive periodontal care.

Material & methods

In this single blind, parallel group, multicentre study, 202 of 203 recruited periodontal maintenance subjects with recurrent or persistent periodontitis were randomly assigned to subgingival ultrasonic/sonic instrumentation (USI) with (test) or without (control) subsequent administration of SRD in all residual periodontal pockets ≥4 mm. Intergroup differences in probing depth, BOP reductions, treatment time, probing attachment levels were evaluated at 3, 6 and 12 months. The primary outcome was the inter‐group difference in absolute change of probing pocket depth (PPD) 3, 6 and 12 months after intervention.

Results

At baseline, the two groups were comparable. At 3 months, the test group showed a significantly higher decrease in mean probing depth than the control group at 3 months (mean difference = 0.11 mm, 95% CI 0.03–0.19 mm, p = 0.003). Administration of SRD resulted in significantly greater odds of transition of bleeding pockets ≥5 mm to a category of non bleeding sites with PPD ≤4 mm at 3 and 6 months (O.R. = 1.4, 95% CI 1.2–1.8 at 3 months). At 6 months, SRD benefit was observed only in the deeper pockets. 7.5% of subjects (no significant difference between test and control) showed disease progression (attachment loss ≥2 mm) and were exited from the study. No difference in the incidence of adverse events was observed between groups.

Conclusion

The trial results show that topically administered SRD may provide short‐term benefit in controlling inflammation and deep pockets in treated periodontal patients participating in a secondary prevention programme and able to maintain a satisfactory level of oral hygiene.
Contact allergy to sodium sulfite and its relationship to sodium metabisulfite
Authors: Oliphant Thomas , Mitra Angana , Wilkinson Mark
Published: February 2012

Background. Sulfites are in widespread use as preservatives/antioxidants. There is increasing recognition of allergic contact dermatitis caused by sodium metabisulfite; however, contact allergy to sodium sulfite is less well recognized.

Objectives. We sought to establish the prevalence of positive patch test reactions to sodium sulfite in our patient population and investigate its relationship with sodium metabisulfite.

Methods. Over a 4‐month period, 183 patients referred for patch testing were tested with sodium sulfite 1% pet. in addition to sodium metabisulfite 1% pet., which already forms part of our baseline series.

Results. Positive allergic reactions occurred to sodium metabisulfite in 5.5% of the tested patients and to sodium sulfite in 3.8% of the tested patients. Sixty per cent of patients with a positive reaction to sodium metabisulfite were positive to sodium sulfite. Only 1 patient (0.6%) with a negative reaction to sodium metabisulfite showed a positive reaction to sodium sulfite.

Conclusions. This study shows that the majority of patients with positive reactions to sodium metabisulfite are also positive to sodium sulphite. Routinely patch testing with sodium sulfite is probably unnecessary, as most patients with positive reactions will also react to sodium metabisulfite. Clinicians should consider advising patients to avoid sodium sulfite and other sulfites when a positive allergic reaction to sodium metabisulfite occurs.
The economic benefits of negative pressure wound therapy in community‐based wound care in the NHS
Authors: Dowsett Caroline , Davis Lynn , Henderson Valerie , Searle Richard
Published: February 2012

The human and economic costs of wounds are of major concern within today's National Health Service. Advances in wound care technology have been shown to be beneficial both in healing and in relation to patient quality of life. Negative pressure has often been associated with high‐cost care and restricted to use in the secondary care setting. There is growing use of negative pressure within the community, and this has the potential to benefit the patient and the service by providing quality care in the patient's home setting. Three community sites were chosen to monitor their use of negative pressure wound therapy (NPWT) over a period of 2 years, and this paper presents some of the key findings of this work. The data generated has been used to help target resources and prevent misuse of therapy. Cost per patient episode has been calculated, and this can be compared to similar costs in secondary care, showing significant savings if patients are discharged earlier from secondary care. There is also an increased demand for more patients with complex wounds to be cared for in the community, and in the future, it is likely that community initiated NPWT may become more common. Early analysis of the data showed that the average cost of dressing complex wounds would be significantly less than using traditional dressings, where increased nursing visits could increase costs. There is a compelling argument for more negative pressure to be used and initiated in the community, based not only on improved quality of life for patients but also on the economic benefits of the therapy.
Planet–planet scattering alone cannot explain the free-floating planet population
Authors: Veras Dimitri , Raymond Sean N.
Published: February 2012

Recent gravitational microlensing observations predict a vast population of free-floating giant planets that outnumbers main-sequence stars almost twofold. A frequently invoked mechanism for generating this population is a dynamical instability that incites planet–planet scattering and the ejection of one or more planets in isolated main-sequence planetary systems. Here, we demonstrate that this process alone probably cannot represent the sole source of these Galactic wanderers. By using straightforward quantitative arguments and N-body simulations, we argue that the observed number of exoplanets exceeds the plausible number of ejected planets per system from scattering. Thus, other potential sources of free floaters, such as planetary stripping in stellar clusters and post-main-sequence ejection, must be considered.
The Prevalence and Determinants of Tobacco Use Among Adolescents in Saudi Arabia
Authors: Al Agili Dania E. , Park Hyoun‐Kyoung
Published: February 2012

BACKGROUND: Adolescent tobacco use has been a serious public health issue, resulting in longer duration of tobacco use and higher nicotine dependence in adulthood. This study identified the current status of tobacco use among middle schools students in Jeddah, Saudi Arabia and the factors leading to tobacco use, to provide information on how to effectively prevent tobacco use among adolescents.

METHODS: A cross‐sectional survey was administered to measure the prevalence of tobacco use and profile tobacco users. School selection was stratified by region, gender, and type (public or private). Altogether, 1186 seventh‐ to ninth‐grade students were selected. Of those, 1019 questionnaires were used for analysis.

RESULTS: The mean age of the participants was 14.3 years (SD = 1.2) and boys comprised 54% of the sample. The prevalence of tobacco use among students was 9.72% with a significant difference between sexes (12.43% for boys and 6.65% for girls). Bivariate and multivariate analyses results showed that students whose families had higher income, had larger daily allowances, spent less time studying, skipped class more frequently, were less religious, spent more time out of home, drank more Coca‐Cola, intended to use tobacco in the next year, and were males who were more likely to use tobacco.

CONCLUSION: Prevention programs designed to reduce adolescent tobacco use need to consider these sociodemographic characteristics. Understanding the characteristics of adolescent tobacco users and the associated sociocultural context is critical for developing effective tobacco prevention programs targeted at adolescents.
The Evolution of HLA‐B*3501 Binding Affinity to Variable Immunodominant NP418‐426 Peptides from 1918 to 2009 Pandemic Influenza A Virus: A Molecular Dynamics Simulation and Free Energy Calculation Study
Authors: Guo Jingjing , Wang Xiaoting , Sun Huijun , Liu Huanxiang , Shen Yulin , Yao Xiaojun
Published: February 2012

Virus‐specific cytotoxic T lymphocytes contribute to the control of virus infections including those caused by influenza viruses. However, during the evolution of influenza A viruses, variations in cytotoxic T lymphocytes epitopes have been observed and it will affect the recognition by virus‐specific cytotoxic T lymphocytes and the human virus‐specific cytotoxic T lymphocytes response in vitro. Here, to gain further insights into the molecular mechanism of the virus‐specific cytotoxic T lymphocytes immunity, the class I major histocompatibility complex‐encoded HLA‐B*3501 protein with six different NP418‐426 antigenic peptides emerging from 1918 to 2009 pandemic influenza A virus were studied by molecular dynamics simulation. Dynamical and structural properties (such as atomic fluctuations, solvent‐accessible surface areas, binding free energy), based on the solvated protein‐peptide complexes, were compared. Free energy calculations emphasized the important role of the secondary anchors (positions 2 and 9) in influencing the binding of MHC‐I with antigenic non‐apeptides. Furthermore, major interactions with peptides were gained from HLA‐B*3501 residues: Tyr7, Ile66, Lys146, Trp147, and Tyr159. Detailed analysis could help to understand how different NP418‐426 mutants effectively bind with the HLA‐B*3501.
Understanding Cultural Issues in Child Development: Introduction
Authors: Chen Xinyin , Eisenberg Nancy
Published: February 2012

Abstract—Research findings indicate that children’s and adolescents’ behaviors may vary in their prevalence, meanings, and developmental patterns across cultures. To explain the cross‐cultural variations, researchers often rely on frameworks based on broad categories such as collectivism versus individualism or interdependent versus independent orientations. However, these frameworks have been criticized for a number of limitations, such as offering overly simplistic categorizations of complex cultural systems, failing to take account of the substantial heterogeneity within societies, and the neglect of the processes in which cultural factors at various contextual levels are involved in individual development. The articles in this Special Section review recent progress in empirical and theoretical work on culture and child development, discuss challenges and problems that researchers are experiencing, and suggest directions for future exploration in the area.
The phenotypic and genetic assessment of protein C deficiency
Authors: COOPER P. C. , HILL M. , MACLEAN R. M.
Published: February 2012

This paper outlines the methods and approaches used for the laboratory detection and investigation of protein C (PC) deficiency. It does not make recommendations as to which patients should have thrombophilia testing performed; this should be done in line with local guidance. Interpretation of PC level is complicated because level varies with age, and many conditions can cause acquired deficiency. Protein C is most usually measured by chromogenic assay as a part of the thrombophilia screen. There exists, however, a very small group of individuals with significant PC deficiency, in whom the chromogenic PC assay is normal. The coagulometric assay of PC is more sensitive to these rare defects, but these assays may lack specificity. Genetic analysis allows definitive diagnosis and may be useful in confirming that deficiency is inherited and not acquired and is particularly valuable in families with severe PC deficiency.
How Social Norms Promote Misleading Social Feedback and Inaccurate Self‐Assessment
Authors: Fay Adam J. , Jordan Alexander H. , Ehrlinger Joyce
Published: February 2012

Self‐assessments are often prone to error. Past research has identified cognitive and motivational biases that lead self‐assessments astray. In the present paper, we discuss how behavior shaped by social norms leaves the negative information that people require for accurate self‐assessments invisible. First, social norms lead people to suppress critical feedback in favor of more positive evaluations. Although people recognize that they prefer to provide positive feedback to others, they fail to consider that they might be the recipient of incomplete feedback. As a result, they are left with overconfident self‐impressions. Second, social norms lead people to hide their own negative emotional experiences from others. Again, people are aware that this positivity norm influences their own behavior but do not apply this knowledge to their understanding of others. As a result, people regard their own negative emotions as more socially aberrant than is actually the case.
Child Sexual Abuse and the Superfluous Association with Negative Parenting Outcomes: The Role of Symptoms as Predictors
Authors: Pazdera Andrea L. , McWey Lenore M. , Mullis Ann , Carbonell Joyce
Published: February 2012

The purpose of this study was to investigate the relationship between child sexual abuse and high‐risk maternal parenting indicators and the extent to which maternal depression and self‐perceived parenting competence influence that relationship. Using path analysis, results indicate maternal depression and parenting sense of competence mediate the relationship between child sexual abuse and outcome variables. Post hoc analyses indicated that child sexual abuse was significantly associated with decreased parenting sense of competence, controlling for depression. These results highlight that the pathways for increased risk in parenting outcomes for child sexual abuse survivors may be indirect and associated with beliefs of their own sense of competence and depression as opposed to a direct association with sexual abuse itself. Implications are discussed.
Microsatellite resources for Passeridae species: a predicted microsatellite map of the house sparrow Passer domesticus
Authors: DAWSON DEBORAH A. , HORSBURGH GAVIN J. , KRUPA ANDREW P. , STEWART IAN R. K. , SKJELSETH SIGRUN , JENSEN HENRIK , BALL ALEXANDER D. , SPURGIN LEWIS G. , MANNARELLI MARIA‐ELENA , NAKAGAWA SHINICHI , SCHROEDER JULIA , VANGESTEL CARL , HINTEN GAVIN N. , BURKE TERRY
Published: February 2012

We identified microsatellite sequences of potential utility in the house sparrow (Passer domesticus) and assigned their predicted genome locations. These sequences included newly isolated house sparrow loci, which we fully characterized. Many of the newly isolated loci were polymorphic in two other species of Passeridae: Berthelot’s pipit Anthus berthelotii and zebra finch Taeniopygia guttata. In total, we identified 179 microsatellite markers that were either isolated directly from, or are of known utility in, the house sparrow. Sixty‐seven of these markers were designed from unique sequences that we isolated from a house sparrow genomic library. These new markers were combined with 36 house sparrow markers isolated by other studies and 76 markers isolated from other passerine species but known to be polymorphic in the house sparrow. We utilized sequence homology to assign chromosomal locations for these loci in the assembled zebra finch genome. One hundred and thirty‐four loci were assigned to 25 different autosomes and eight loci to the Z chromosome. Examination of the genotypes of known‐sex house sparrows for 37 of the new loci revealed a W‐linked locus and an additional Z‐linked locus. Locus Pdoμ2, previously reported as autosomal, was found to be Z‐linked. These loci enable the creation of powerful and cost‐effective house sparrow multiplex primer sets for population and parentage studies. They can be used to create a house sparrow linkage map and will aid the identification of quantitative trait loci in passerine species.
Das Bootand the German Cinema of Neoliberalism1
Authors: Baer Hester
Published: February 2012

This essay reconsiders the international blockbusterDas Booton the thirtieth anniversary of its release, arguing that the film played a pivotal role in the shift from theAutorenkinoof the 1960s and 1970s to a new, market‐driven producers' cinema with transnational appeal. My analysis readsDas Bootin the context of Deleuze's film theory, suggesting thatCinemacan open up productive standpoints for examining popular cinema, but also pointing to some limitations of Deleuze's work for understanding the politics of commercial film today. Emphasizing the wayDas Bootco‐opts aesthetic and political strategies of art cinema, I focus especially on its representation of (trans)nationalism, gender, and sexuality. A highly popular film that has rarely been analyzed by scholars,Das Bootsuggests that cultural formations have played a crucial role in the process of neoliberalization in Germany.
Money, Mobility, and Commodified Bodies: The Politics of Gentrification in German City Films of the Late 1990s
Authors: Stehle Maria
Published: February 2012

In the late 1990s Hamburg and Berlin launched large‐scale urban reconstruction projects, theHafenCity Masterplanin Hamburg and thePlanwerk Innenstadtin Berlin. Both projects triggered debates among politicians, activists, and journalists about the future of German/European cities, and spaces for creativity, art, and alternative cultures within increasingly commercialized and gentrified cityscapes. After an overview of these debates, this article discusses two German city episode films, Sönke Wortmann'sSt. Pauli Nacht(1999) and Andreas Dresen'sNachtgestalten(1998), in the context of discussions about the politics of the neoliberal city. The films offer different perspectives on how bodies and money circulate in the shadow spaces of neoliberal cityscapes. The cinematic depictions of these economies, however, can be commodified into marketable fantasies of “edgy Berlin” and “seedy Hamburg.”
Response‐guided therapy for patients with chronic hepatitis who have high viral loads of hepatitis C virus genotype 2
Authors: Yamaguchi Yasunori , Tamori Akihiro , Tanaka Yasuhito , Iwai Shuji , Kobayashi Sawako , Fujii Hideki , Morikawa Hiroyasu , Hagihara Atsushi , Enomoto Masaru , Kawada Norifumi
Published: February 2012

Aim:  We evaluated the efficacy of response‐guided therapy in patients with hepatitis C virus (HCV) genotype 2.

Methods:  We studied 105 patients with an HCV genotype 2 load of higher than 5.0 Log IU/mL who received more than 75% of the target dose of pegylated interferon plus ribavirin. Among patients with rapid viral response (RVR; no HCV RNA detected at week 4), 14 selected 16 weeks of therapy (group A), and 28 selected 24 weeks of therapy (group B). Among non‐RVR patients, 40 selected 24 weeks of therapy (group C), and 19 selected 48 weeks of therapy (group D).

Results:  All patients in group A and B achieved a sustained viral response (SVR). Clinical characteristics did not differ significantly between groups C and D. However, the proportion of patients in whom HCV RNA disappeared at a later week after starting treatment was higher in group D (P = 0.0578). SVR rate was 73% in C, and 79% in D. Among patients in whom HCV RNA disappeared between weeks 5 and 8, SVR was achieved in 28 (82%) of 34 patients in C and 10 (91%) of 11 patients in D. Among patients whose HCV RNA disappeared between weeks 9 and 12, SVR was achieved in one (20%) of five patients in C and five (63%) of eight patients in D (not statistically significant).

Conclusions:  16 weeks of combination therapy could achieve an adequate antiviral effect for RVR patients. Extending therapy could not significantly improve SVR rate in non‐RVR patients.
Influence of chronic stress on the compositions of hepatic cholesterol and triglyceride in male Wistar rats fed a high fat diet
Authors: Gao Siyuan , Han Xue , Fu Jihua , Yuan Xiaoling , Sun Xing , Li Qiang
Published: February 2012

Aim:  We determined the influence of chronic stress (CS) on the compositions of hepatic cholesterol and triglyceride (TG) in rats fed a high fat diet (HFD).

Methods:  Male Wistar rats were fed either a standard diet or a HFD and half of the HFD fed rats were given CS (electric foot shock assisted with noise) for 8 weeks.

Results:  Compared with the control group, the levels of hepatic total cholesterol (TC) and TG were significantly elevated in the HFD and HFD with chronic stress (HFD+CS) groups, and the more severe elevations of them were found in the HFD group. Inversely, the more severe elevations of hepatic water‐soluble parts of TC and TG were found in the HFD+CS group, as the elevations of low‐density lipoprotein cholesterol, very low‐density lipoprotein cholesterol in liver and serum, tumor necrosis factor‐α, interleukin‐1β and malondialdehyde in liver. Meanwhile, downregulated mRNA expressions of hepatic liver X receptor‐α (LXR‐α) and peroxisome proliferator‐activated receptor‐γ (PPAR‐γ) were also more severe in the HFD+CS group.

Conclusion:  CS can aggravate the high levels of water‐soluble compositions of hepatic TC and TG induced by HFD as it aggravates hepatic inflammation and oxidative stress; in spite of that, however, it cannot further promote hepatic lipidosis. This is consistent with the downregulated mRNA expressions of LXR‐α and PPAR‐γ.
Cytologic and immunohistochemical characterization of a primitive neuroectodermal tumor in the brain of a dog
Authors: Choi Ul Soo , Philippe Labelle , Alleman A. Rick , Kim Min Su , Lee Ki Chang
Published: February 2012

A 6‐year‐old intact femalePointer dog was presented for evaluation of acute onset of ataxia, circling, and head tilt. Neurologic assessment revealed overall decreased postural reaction, left‐sided hemiparesis with incoordination, rigidity of fore‐ and hindlimbs, strabismus of the right eye, and bilateral horizontal nystagmus. Using magnetic resonance imaging, a mass lesion was identified in the cerebrum adjacent to the left side of the cerebellum compressing the brain stem ventrally. The mass was incompletely resected, and during surgery fine‐needle aspiration and biopsy of the mass were performed. Cytologically, smears were highly cellular and contained predominantly small to medium‐sized discrete round cells with high nuclear to cytoplasmic ratios and round nuclei with rare deep clefts or indentation, smooth chromatin, and indistinct nucleoli. Numerous cytoplasmic fragments were noted in the background. The primary diagnosis was lymphoma; other differential diagnoses included neuroendocrine tumor and poorly differentiated tumor of neural origin. The histologic diagnosis was lymphoma, and the lesion was presumed to be metastatic. On immunohistochemical analysis, the cells expressed neitherCD3 norCD79a. Re‐examination of the histologic section revealed disorganized sheets of cells with multifocal palisading and perivascular arrangements of rosette‐like structures. An expanded panel of antibodies to vimentin, cytokeratin, glial fibrillary acid protein (GFAP), neuron‐specific enolase (NSE), synaptophysin (SYN),S‐100, andCD45 was applied to histologic sections. Neoplastic cells were immunoreactive for vimentin,NSE, andS‐100. Based on the histologic appearance and immunophenotype of the tumor, a diagnosis of primitive neuroectodermal tumor (PNET) was made.PNET, although rare in dogs, should be considered as a differential diagnosis for round cell tumors in the brain.
Understanding Controls, Behaviors and Satisfaction in the Daylit perimeter office: A Daylight Design Case Study
Authors: Day Julia , Theodorson Judy , Van Den Wymelenberg Kevin
Published: February 2012

Daylight has the potential to positively impact occupants and reduce energy consumption in buildings if utilized correctly ( Edwards & Torcellini, 2002 ). However, unintended negative outcomes can arise from unsuccessful daylighting schemes. Common issues, such as glare and heat gain, are important architectural considerations in design of the building envelope, but less studied are corresponding interior design considerations ( such as furniture layout and access to controls) and associated occupant interactions and appraisals. The purpose of the current study is to expose some of the key issues related to the occupant use of daylight and daylight control in perimeter offices, to discuss the contributing design process factors, and to suggest possible improvements to the design process including an increased role for interior designers. The research methodology followed a case study approach and included post–occupancy evaluation (POE) questionnaires, interviews, and observations of a single higher education building with intentionally daylit perimeter offices. We discovered that the building in question was passed between three separate design teams throughout the design process, which may have contributed to the lack of integration between the architectural daylight design and the interior furniture and daylighting control fit–out. More than 50% of total respondents ( n = 35) reported obstructed blind controls due to poor furniture design and layout. Of these, nearly 60% of occupants modified their office environment to gain access to blind controls. Ultimately, findings of this study demonstrate the importance of an integrated, multidisciplinary approach to daylighting design, one that considers both the specific building context and the human response.
Hopelessness as a Predictor of Attempted Suicide among First Admission Patients with Psychosis: A 10‐year Cohort Study
Authors: David Klonsky E. , Kotov Roman , Bakst Shelly , Rabinowitz Jonathan , Bromet Evelyn J.
Published: February 2012

Little is known about the longitudinal relationship of hopelessness to attempted suicide in psychotic disorders. This study addresses this gap by assessing hopelessness and attempted suicide at multiple time‐points over 10 years in a first‐admission cohort with psychosis (n = 414). Approximately one in five participants attempted suicide during the 10‐year follow‐up, and those who attempted suicide scored significantly higher at baseline on the Beck Hopelessness Scale. In general, a given assessment of hopelessness (i.e., baseline, 6, 24, and 48 months) reliably predicted attempted suicide up to 4 to 6 years later, but not beyond. Structural equation modeling indicated that hopelessness prospectively predicted attempted suicide even when controlling for previous attempts. Notably, a cut‐point of 3 or greater on the Beck Hopelessness Scale yielded sensitivity and specificity values similar to those found in nonpsychotic populations using a cut‐point of 9. Results suggest that hopelessness in individuals with psychotic disorders confers information about suicide risk above and beyond history of attempted suicide. Moreover, in comparison with nonpsychotic populations, even relatively modest levels of hopelessness appear to confer risk for suicide in psychotic disorders.
Precipitating Events in Adolescent Suicidal Crises: Exploring Stress‐Reactive and Nonreactive Risk Profiles
Authors: Hill Ryan M. , Pettit Jeremy W. , Green Kelly L. , Morgan Sharon T. , Schatte Dawnelle J.
Published: February 2012

Factors distinguishing adolescents who experienced a precipitating event in the week preceding a suicidal crisis from those who did not were examined. Among 130 suicidal inpatients (mean age = 15.01 years), those who experienced a precipitating event reported significantly lower depressive symptom scores, better perceived problem solving, less suicidal intent, and a lower rate of prior suicide attempts than those without a precipitating event. Levels of trait impulsivity, suicidal ideation, and current attempt status did not differentiate groups. Findings provide preliminary evidence consistent with at least two possible pathways to a suicidal crisis. Clinical implications and future directions are discussed.
Tumor necrosis factor‐α and interleukin‐1β expression pathway induced by Streptococcus mutans in macrophage cell line RAW 264.7
Authors: Kim J.S. , Kim K.D. , Na H.S. , Jeong S.Y. , Park H.R. , Kim S. , Chung J.
Published: February 2012

Streptococcus mutans, a major etiological agent of dental caries, frequently causes systemic disease, such as subacute bacterial endocarditis, if it enters the bloodstream. In this study, the production pathways of the proinflammatory cytokines, tumor necrosis factor‐α (TNF‐α) and interleukin‐1β (IL‐1β), induced by S. mutans in mouse macrophage were examined using a quantitative real‐time polymerase chain reaction and an enzyme‐linked immunosorbent assay. The S. mutans stimulated the expression of TNF‐α and IL‐1β mRNA at a multiplicity of infection of 1 : 100, which increased at 2 and 4 h, respectively, to 24 h. It also induced the production of high levels of the TNF‐α and IL‐1β proteins, which increased at 2 h and reached a peak at 4 and 24 h, respectively. Nuclear factor‐κB (NF‐κB) was activated and reached a maximum level 30 min after the S. mutans treatment. The expression of TNF‐α and IL‐1β mRNA and protein was suppressed by the treatment with pyrrolidine dithiocarbamate, an NF‐κB inhibitor. The S. mutans‐induced TNF‐α expression was suppressed by the presence of SB203580, a p38 mitogen‐activated protein (MAP) kinase inhibitor, or SP600125, a Jun N‐terminal kinase (JNK) MAP kinase inhibitor. On the other hand, IL‐1β expression was inhibited by extracellular signal‐regulated kinase (ERK)/p38/JNK MAP kinase inhibitor pretreatment. In addition, TNF‐α production was suppressed more in the Toll‐like receptor 2−/− (TLR2−/−) macrophages than in the TLR4−/− macrophages, whereas IL‐1β production was suppressed more in the TLR4−/− macrophages than in the TLR2−/− macrophages. These results show that S. mutans stimulates the production of TNF‐α and IL‐1β in the mouse macrophage cell line, RAW 264.7, by activating ERK/p38/JNK, and NF‐κB through TLR2 and TLR4, respectively.
Energy expenditure and insulin sensitivity evaluation in obese children affected by hepatosteatosis
Authors: Fintini D. , Pietrobattista A. , Morino G. , Cafiero G. , Calzolari A. , Turchetta A. , Brufani C. , Alisi A. , Giordano U. , Nobili V.
Published: February 2012

Objectives

The aim of our study was to evaluate the physical and sedentary activities and energy expenditure (EE) in a group of children affected by non‐alcoholic fatty liver disease (NAFLD), compared with normal and obese subjects, using a physical activity questionnaire (PAQ) and a SenseWear armband (SWA).

Methods

Forty NAFLD (10 females), 41 lean (NRM; 11 females) and 30 obese (OB; 10 females), age‐ and pubertal stage‐matched, children were included.

Results

Sedentary activity (PAQ) was similar in NAFLD and NRM but less in OB, while SWA showed that NAFLD spent less time in physical activity and more in sedentary activities compared with NRM, but not with OB. Insulin sensitivity index result is related to active EE (cal kg–1 d–1) in NAFLD, while homeostatic model assessment index result was negatively related to total EE in OB.

Conclusions

Regular physical activity must be encouraged in all obese children affected by NAFLD or not, and SWA might be a possible valid tool for evaluating actual EE.
Analysis of Laminar Flow Over a Non-Conventional Random Rough Surface Based on Lattice Boltzmann Method
Authors: Zhou Ping , Guo Dongming , Kang Renke , Jin Zhuji
Published: February 2012

The average flow model offers a great convenience for the analysis of laminar flow over rough surfaces and is widely used in simulation studies. Flow factors used in the average flow model are generally expressed as a function of statistical properties of a single level rough surface with gentle slopes. However, for a nonconventional surface with multilevel roughness or high local surface slopes, such as polishing pads used in chemical mechanical planarization (CMP), it has not been verified whether this model is still applicable as expected. Generally, computations based on the Reynolds equation are carried out repeatedly for the same problem regarding different but statistically identical rough surfaces, and the average flow model is applicable if stable flow factors (statistical average) are obtained. However, due to the complex topography and high local surface slopes of polishing pads used in CMP, the Reynolds equation is no longer valid, and thus a new method needs to be developed to estimate the applicability of the average flow model and to calculate the flow factors accurately. In this study, aiming to research the flow over a nonconventional random rough surface such as the slurry flow in CMP, a new strategy is developed to research the incompressible laminar flow through a narrow gap between various nonconventional rough surfaces by combining the lattice Boltzmann method (LBM) and numerical simulation of random rough surface. With this strategy, it is convenient to simulate the flow field in a narrow gap between various random rough surfaces and obtain the flow factors. In addition, an analytical formula for calculating the flow factors of a dual-level rough surface, i.e., surface composed of two different types of microstructure, is introduced and verified through a comparison with the results obtained using the presented numerical simulation strategy.
Measurement of Wheel/Rail Load Environment in Relation to Rolling Contact Fatigue
Authors: Cummings Scott , Reiff Richard , Punwani John , Snyder Todd
Published: February 2012

Wheel shelling is the cause of a large portion of high impact wheels. The impact loads produced by shelled wheels can have a damaging effect on track components and rolling stock components such as roller bearings. Shelling is the result of accumulated rolling contact fatigue (RCF) on the wheel tread surface. To investigate the specific conditions in which RCF occurs, wheel load environment data was collected from a car with three-piece trucks running in revenue service. This data was analyzed in order to assess the predicted wheel RCF through the use of shakedown theory. An inspection team was dispatched to several track sites to record relevant information including a visual assessment of rail RCF, rail transverse profile, rail age, and friction conditions. Track inspections were conducted at locations where RCF was predicted and at nearby locations with similar curvature where RCF was not predicted. Conclusions from this work are the following: • The curve unbalance condition, which is a combination of curvature, track superelevation, and train speed, is an important factor in RCF. • Wheel/rail coefficient of friction in curves can be a factor in RCF. • Rail profile and track condition were not found to be major factors in this analysis. • Observed rail RCF condition correlated reasonably well with predictions when considering extenuating factors such as rail age and curve unbalance conditions. • Confidence was increased in previous simulation results involving three-piece trucks due to good correlation with the results of the current work. The simulation results suggest that the use of AAR approved M-976 trucks should reduce RCF. This work was funded by the Federal Railroad Administration (FRA) and the Wheel Defect Prevention Research Consortium (WDPRC), a group that includes railroads, private car owners, and industry suppliers.
Disruption Management With Rescheduling of Trips and Vehicle Circulations
Authors: Lorek Martin , Fekete Sa´ndor P. , Kro¨ller Alexander , Pfetsch Marc E.
Published: February 2012

This paper introduces a combined approach for the recovery of a timetable by rescheduling trips and vehicle circulations for a rail-based transportation system subject to disruptions. We propose a novel event-based integer programming (IP) model. Features include shifting and canceling of trips as well as modifying the vehicle schedules by changing or truncating the circulations. The objective maximizes the number of recovered trips, possibly with delay, while guaranteeing a conflict-free new timetable for the estimated time window of the disruption. We demonstrate the usefulness of our approach through experiments for real-life test instances of relevant size, arising from the subway system of Vienna. We focus on scenarios in which one direction of one track is blocked, and trains have to be scheduled through this bottle-neck. Solving these instances is made possible by contracting parts of the underlying event-activity graph; this allows a significant size reduction of the IP. Usually, the solutions found within one minute are of good quality and can be used as good estimates of recovery plans in an online context.
Analytical Possibilities of Doing Capacity Research in Rail Station Areas
Authors: Lindner Tobias
Published: February 2012

Railway specialists expect that the demand for rail-bound passenger and freight traffic in the US will increase enormously in the coming years. Implementing the American Recovery and Reinvestment Act (ARRA) of 2009, new high-speed lines will be created throughout the nation. This will lead to an additional increase of passenger traffic demand. Experiences from Western Europe have shown that new high-speed passenger lines will cause changes in user demand behavior as well as an augmentation of the importance of regional lines featuring connections to the high-speed network. The existing stations will not only be greater utilized by the new high-speed lines, but a growth in demand for regional lines could also require an increasing number of trains. That could lead to greater infrastructure utilization as well. Both aspects lead to the question of whether the already existing large stations of the future high-speed network possess enough capacity for handling such a large number of trains. It is comprehensible that station capacity will play a very important role for planning new corridors. While UIC Code 406 contains first steps of defining a standardized method for doing line capacity research, it does not include any information about station capacity evaluations. A few analytical methods for doing such evaluations are described in this paper. Most of these methods are easy to apply but offer important values for evaluating existing station infrastructure as well as timetables. It is also shown that the compression method presented in UIC Code 406 cannot be used for doing station capacity research.
Shared Use of Railway Corridors by Public Transit Vehicles
Authors: Eyquem Alexandre J. M. , Hutchins Joseph Lee , Taylor Christopher , Falcetta John
Published: February 2012

As transportation corridors become an ever more important asset, existing rail freight corridors are under increasing pressure to be shared for transit purposes. In defining the expanded corridor use a comprehensive look at factors was undertaken on behalf of Transport Canada by AECOM. Understanding the issues is imperative in navigating this complex subject. In locations where the transit network and expected ridership-generation points are compatible with existing railway networks, the best use of a network of corridors for freight and transit should be one of the first steps in municipal and regional planning. Finding a best use of existing network typically does not happen for two reasons. First, the public entities typically do not observe the complete “freight network” and have a limited stake in its function and complexity. Unlike public roads or transit, public entities tend to look at single opportunities such as little used freight segments, or specific corridors that they can afford to pursue with a specific public purpose. As a result, freight railways often find themselves responding to a specific request for a segment in the context of their network and whether it serve a functional need. Second, the private freight railways similarly do not have opportunity or patience to investigate the public contribution to their networks. The point of view of what might be done if the potential transit services were understood and what it could mean to freight business with capital investment in an improved and/or rationalized freight delivery system may be hard to define, and the benefits may only occur in the distant future. They have a priority to pursue their immediate business model and therefore tend to wait until the public entity comes forward and asks about a specific corridor or opportunity. The issue of assets inventory, rationalization paired with transit planning, is the first step in evaluating efficient transportation systems through urban centres. Furthermore, the ability of some transit vehicles to be used on both on dedicated railway transit corridors, where it makes sense, as well as for street services, provide for greater flexibility in transit networks. What is missing is a review of freight networks from a regional perspective relative to all potential transit routes. The first question to be asked when looking at the freight network of an urban area is: where is it going, why is it going there, and could it be handled more effectively, and if so what are the overall benefits to all parties.
Tie-Plate Cracking on Wood/Composite Ties: A Parametric Study
Authors: Tangtragulwong Potchara , Fry Gary T. , Davis David D. , Reiff Richard P.
Published: February 2012

Composite ties are commonly used as a replacement for wood ties because of many advantages. For example, composite ties show higher decay and corrosion resistance, greater compatibility with available fastening methods, and the ability to be inter-mixed with wood ties. However, recently, premature fatigue failures of tie plates installed on composite ties have been found at the TTCI test facility, while no failures had been found in tie plates installed on wood ties. This paper presents an investigation of tie plate failures using finite element analysis. A full-scale finite element model of the involved components—consisting of axle, wheel, rail, tie plate, and tie—is developed with an application of vertical and lateral loads on the axle. Three contact interfaces—between wheel-rail, rail-tie plate, and tie plate-tie, are defined to simulate actual operational configuration. To investigate the bending stresses in tie plates as a result of wheel-rail rolling contact, a parametric study of the elastic modulus of the ties, and the applied vertical and lateral wheel loads is examined. Results show that 1) given typical vertical and lateral loads, the decrease of tie’s elastic modulus increases transverse (bending) stresses at the base of the tie plate; thus, promoting high-cycle fatigue failures, and 2) in addition to the vertical load, the lateral loads also have a significant effect on the bending stress in the tie plate, 3) spike-hole cracking is the dominant mode of failure in composite ties operated under all simulated load cases, while edge failure is dominant in wood ties operated under a large lateral load.
Fuel Tank Crashworthiness: Loading Scenarios
Authors: Jacobsen Karina
Published: February 2012

The Federal Railroad Administration’s Office of Research and Development is conducting research into fuel tank crashworthiness. The breaching of fuel tanks during passenger rail collisions and derailments increases the potential of serious injury and fatality due to fire. This paper identifies and describes common collision loading scenarios for locomotive fuel tanks on the U.S. general railroad system. Developing scenarios that characterize this situation is the first step in crashworthiness research methodology for improving rail equipment safety. A survey of accidents within the U.S. between 1995 and present was used to identify fuel tank impact scenarios as follows: impact with adjacent railcar component; oblique impact with another railcar; rollover leading to impact with another railcar; derailment or rollover leading to grounding; and impact with rail. These collision scenarios are further categorized by the types of collision modes experienced by the fuel tank, i.e. impact type and impact location. These loading conditions establish targets for evaluating current levels of fuel tank integrity and potentially developing improved strategies for enhancing fuel tank integrity.