bluuebunny/crossref_metadata_2025 huggingface dataset:
Does divergence in female mate choice affect male size distributions in two cave fish populations?
Authors: Tobler Michael , Schlupp Ingo , Plath Martin
Published: June 2008

Sexual selection by female choice can maintain male traits that are counter selected by natural selection. Alteration of the potential for sexual selection can thus lead to shifts in the expression of male traits. We investigated female mate choice for large male body size in a fish (
Poecilia mexicana
) that, besides surface streams, also inhabits two caves. All four populations investigated, exhibited an ancestral visual preference for large males. However, only one of the cave populations also expressed this female preference in darkness. Hence, the lack of expression of female preference in darkness in the other cave population leads to relaxation of sexual selection for large male body size. While
P. mexicana
populations with size-specific female mate choice are characterized by a pronounced male size variation, the absence of female choice in one cave coincides with the absence of large bodied males in that population. Our results suggest that population differences in the potential for sexual selection may affect male trait variation.
Proto-Plasm
: parallel language for adaptive and scalable modelling of biosystems
Authors: Bajaj Chandrajit , DiCarlo Antonio , Paoluzzi Alberto
Published: June 2008

This paper discusses the design goals and the first developments of
Proto-Plasm
, a novel computational environment to produce libraries of executable, combinable and customizable computer models of natural and synthetic biosystems, aiming to provide a supporting framework for predictive understanding of structure and behaviour through multiscale geometric modelling and multiphysics simulations. Admittedly, the
Proto-Plasm
platform is still in its infancy. Its computational framework—language, model library, integrated development environment and parallel engine—intends to provide patient-specific computational modelling and simulation of organs and biosystem, exploiting novel functionalities resulting from the symbolic combination of parametrized models of parts at various scales.
Proto-Plasm
may define the model equations, but it is currently focused on the symbolic description of model geometry and on the parallel support of simulations. Conversely, CellML and SBML could be viewed as defining the behavioural functions (the model equations) to be used within a
Proto-Plasm
program. Here we exemplify the basic functionalities of
Proto-Plasm
, by constructing a schematic heart model. We also discuss multiscale issues with reference to the geometric and physical modelling of neuromuscular junctions.
The EuroPhysiome, STEP and a roadmap for the virtual physiological human
Authors: Fenner J.W , Brook B , Clapworthy G , Coveney P.V , Feipel V , Gregersen H , Hose D.R , Kohl P , Lawford P , McCormack K.M , Pinney D , Thomas S.R , Van Sint Jan S , Waters S , Viceconti M
Published: June 2008

Biomedical science and its allied disciplines are entering a new era in which computational methods and technologies are poised to play a prevalent role in supporting collaborative investigation of the human body. Within Europe, this has its focus in the virtual physiological human (VPH), which is an evolving entity that has emerged from the EuroPhysiome initiative and the strategy for the EuroPhysiome (STEP) consortium. The VPH is intended to be a solution to common infrastructure needs for physiome projects across the globe, providing a unifying architecture that facilitates integration and prediction, ultimately creating a framework capable of describing
Homo sapiens in silico
. The routine reliance of the biomedical industry, biomedical research and clinical practice on information technology (IT) highlights the importance of a tailor-made and robust IT infrastructure, but numerous challenges need to be addressed if the VPH is to become a mature technological reality. Appropriate investment will reap considerable rewards, since it is anticipated that the VPH will influence all sectors of society, with implications predominantly for improved healthcare, improved competitiveness in industry and greater understanding of (patho)physiological processes. This paper considers issues pertinent to the development of the VPH, highlighted by the work of the STEP consortium.
Host factors involved in resistance to retroviral infection
Authors: Takeuchi Hiroaki , Matano Tetsuro
Published: June 2008

Viral replication requires the help of host cell factors, whose species specificity may affect viral tropism. On the other hand, there exist host factors that restrict viral replication. The anti‐viral system mediated by some of these restriction factors, which is termed intrinsic immunity and is distinguished from conventional innate and adaptive immunity, has been described as playing an important role in making species‐specific barriers against viral infection. Here, we describe the current progress in understanding of such restriction factors against retroviral replication, focusing on TRIM5α and APOBEC, whose anti‐retroviral effects have recently been recognized. Additionally, we mention cyclophilin A, which is essential for HIV‐1 replication in human cells and may affect viral tropism. Understanding of these host factors would contribute to identification of the determinants for viral tropism.
Hemispheric‐scale patterns of climate‐related shifts in planktonic diatoms from North American and European lakes
Authors: RÜHLAND KATHLEEN , PATERSON ANDREW M. , SMOL JOHN P.
Published: June 2008

A synthesis of over 200 diatom‐based paleolimnological records from nonacidified/nonenriched lakes reveals remarkably similar taxon‐specific shifts across the Northern Hemisphere since the 19th century. Our data indicate that these diatom shifts occurred in conjunction with changes in freshwater habitat structure and quality, which, in turn, we link to hemispheric warming trends. Significant increases in the relative abundances of planktonic Cyclotella taxa (P<0.01) were concurrent with sharp declines in both heavily silicified Aulacoseira taxa (P<0.01) and benthic Fragilaria taxa (P<0.01). We demonstrate that this trend is not limited to Arctic and alpine environments, but that lakes at temperate latitudes are now showing similar ecological changes. As expected, the onset of biological responses to warming occurred significantly earlier (P<0.05) in climatically sensitive Arctic regions (median age=ad 1870) compared with temperate regions (median age=ad 1970). In a detailed paleolimnological case study, we report strong relationships (P<0.005) between sedimentary diatom data from Whitefish Bay, Lake of the Woods (Ontario, Canada), and long‐term changes in air temperature and ice‐out records. Other potential environmental factors, such as atmospheric nitrogen deposition, could not explain our observations. These data provide clear evidence that unparalleled warming over the last few decades resulted in substantial increases in the length of the ice‐free period that, similar to 19th century changes in high‐latitude lakes, likely triggered a reorganization of diatom community composition. We show that many nonacidified, nutrient‐poor, freshwater ecosystems throughout the Northern Hemisphere have crossed important climatically induced ecological thresholds. These findings are worrisome, as the ecological changes that we report at both mid‐ and high‐latitude sites have occurred with increases in mean annual air temperature that are less than half of what is projected for these regions over the next half century.
Prolactin receptor expression in gynaecomastia and male breast carcinoma
Authors: Ferreira M , Mesquita M , Quaresma M , André S
Published: June 2008

Aims:  Despite the well‐established function of prolactin (PRL) in normal breast development, its role in breast cancer pathogenesis is still controversial. PRL activity is dependent on the activation of a transmembrane protein, the PRL receptor (PRLR). The aim was to evaluate and compare PRLR expression in gynaecomastia and male breast carcinoma (MBC).

Methods and results:  PRLR expression was detected immunohistochemically in 30 cases of gynaecomastia and 30 cases of MBC. The whole series was also assessed for oestrogen receptors (ER), progesterone receptors (PR) and androgen receptors (AR). A cut‐off of 10% was used as the criterion for positivity. Histological type and tumour differentiation were evaluated. Pathological stage was assessed [Tumour Node Metastasis (TNM)‐International Union Against Cancer system]. Statistical analysis was performed with Fisher’s exact test. PRLR positivity was seen in 20% of gynaecomastia cases and in 60% of MBC cases (P = 0.003). In gynaecomastia immunoreactivity was predominantly observed in luminal cell borders, whereas in MBC the reactivity was heterogeneous and mainly cytoplasmic. There was no statistically significant correlation between PRLR expression and ER, PR, AR, pTNM, or histological grade.

Conclusions:  PRLR is significantly more expressed in MBC than in gynaecomastia, and with different patterns of reactivity, suggesting a role for PRL in male breast carcinogenesis.
Ki67 index in intracranial ependymoma: a promising histopathological candidate biomarker
Authors: Preusser M , Heinzl H , Gelpi E , Höftberger R , Fischer I , Pipp I , Milenkovic I , Wöhrer A , Popovici F , Wolfsberger S , Hainfellner J A
Published: June 2008

Aims:  The Ki67 tumour cell proliferation index is an independent prognostic factor in ependymoma patients. Essential prerequisites for validation of the Ki67 index as a histopathological biomarker are the reproducibility of this factor and its prognostic influence by different observers (proof of objective clinical and analytical performance). To this end, the aim was to analyse systematically inter‐ and intraobserver agreement and reproducibility of the prognostic impact of the Ki67 index in intracranial ependymoma.

Methods and results:  The study cohort contained 78 cases of intracranial ependymoma. In all cases, the Ki67 index was assessed by four experienced observers (EOs) and by four inexperienced observers (IOs) using the manual hot‐spot method. There was considerable agreement on Ki67 index assessment. There was higher observer agreement among EOs compared with IOs. For each observer, survival analysis showed significant association of low Ki67 index with favourable patient outcome.

Conclusions:  Our data show that the Ki67 index in intracranial ependymoma is a reproducible and robust prognostic factor and can be considered a promising histopathological candidate biomarker. Attainment of biomarker status requires further translational studies in the context of prospective therapeutic trials.
A secular theory of coplanar, non-resonant planetary system
Authors: Migaszewski Cezary , Goździewski Krzysztof
Published: June 2008

We present the secular theory of coplanar N-planet system, in the absence of mean motion resonances between the planets. This theory relies on the averaging of a perturbation to the two-body problem over the mean longitudes. We expand the perturbing Hamiltonian in Taylor series with respect to the ratios of semimajor axes which are considered as small parameters, without direct restrictions on the eccentricities. Next, we average out the resulting series term by term. This is possible thanks to a particular but in fact quite elementary choice of the integration variables. It makes it possible to avoid Fourier expansions of the perturbing Hamiltonian. We derive high-order expansions of the averaged secular Hamiltonian (here, up to the order of 24) with respect to the semimajor axes ratio. The resulting secular theory is a generalization of the octupole theory. The analytical results are compared with the results of numerical (i.e. practically exact) averaging. We estimate the convergence radius of the derived expansions, and we propose a further improvement of the algorithm. As a particular application of the method, we consider the secular dynamics of three-planet coplanar system. We focus on stationary solutions in the HD 37124 planetary system.
Dendritic Cells from Peyer’s Patches and Mesenteric Lymph Nodes Differ from Spleen Dendritic Cells in their Response to Commensal Gut Bacteria
Authors: Fink L. N. , Frøkiær H.
Published: June 2008

Commensal gut bacteria have potent effects on the immune system, which are partially mediated by intestinal dendritic cells (DC). Distinct commensals confer different properties to in vitro‐generated DC. The aim of the present study was to reveal strain‐dependent maturation patterns in primary DC. To this end, we compared the response of mouse Peyer’s patch (PP) DC, mesenteric lymph node (MLN) DC and spleen DC to the commensal bacteria, Bifidobacterium longum Q46, Lactobacillus acidophilus X37 and Escherichia coli Nissle 1917. Bacterial maturation of DC occurred independently of tissue origin. Expression of CCR7 and CD103 on the surface of MLN DC, necessary for the induction of gut‐homing regulatory T cells, increased with stimulation by Gram‐positive commensals. Bacteria‐dependent cytokine production (IL‐6, IL‐10 and TNF‐α) was similar in spleen and MLN DC, and contaminant cells in these DC preparations produced IFN‐γ in response to L. acidophilus. In contrast, PP DC produced IL‐6 only in response to E. coli, little IL‐10 and no TNF‐α, and this low cytokine production was not due to inhibition by IL‐10 or TGF‐β. Bifidobacteria downregulate IL‐6, TNF‐α and IL‐12 production induced in in vitro‐generated DC by L. acidophilus. Similar inhibition was observed in splenic DC, but not in MLN DC. MLN cells responded to bacterial stimulation with higher IFN‐γ production than spleen cells, possibly due to the presence of more responsive natural killer cells. Commensal bacteria therefore play specific roles in the gut immune system distinguishable from the effect they would have if recognized by the systemic immune system.
Global climate change: time to mainstream health risks and their prevention on the medical research and policy agenda
Authors: Tong S. , Mackenzie J. , Pitman A. J. , FitzGerald G. , Nicholls N. , Selvey L.
Published: June 2008

Climate change is unequivocal. The fourth assessment report of the Intergovermental Panel on Climate Change has recently projected that global average surface temperature will increase by 1.1 to 6.4°C by 2100. Anthropogenic warming during the twenty‐first century would be much greater than that observed in the twentieth century. Most of the warming observed over the last six decades is attributable to human activities. Climate change is already affecting, and will increasingly have profound effects on human health and well‐being. Therefore, there is an urgent need for societies to take both pre‐emptive and adaptive actions to protect human populations from adverse health consequences of climate change. It is time to mainstream health risks and their prevention in relation to the effects of climate change on the medical research and policy agenda.
Nephron‐sparing surgery: a call for greater application of established techniques
Authors: Young James G. , Luscombe Christopher J. , Lynch Ciaran , Wallace D. Michael A.
Published: June 2008

OBJECTIVES

To examine the results of open partial nephrectomy (OPN) over a 15‐year period in a large UK teaching hospital and to compare results with other series including minimally invasive techniques, as nephron‐sparing techniques are still under‐utilized in the surgical treatment of renal carcinoma. A standardized technique is described that we think minimizes the risk of postoperative urinoma.

PATIENTS AND METHODS

We retrospectively reviewed a series of 141 patients who underwent OPN performed over a 15‐year period in one centre by the senior author (D.M.A.W.). A notable feature of this series compared with others is the high proportion of patients undergoing other major synchronous surgery.

RESULTS

In all, 141 patients underwent 147 OPNs, with six undergoing bilateral procedures, of which 82 were for imperative indications (single kidney, bilateral synchronous tumours, or pre‐existing renal impairment). There were three perioperative deaths, two in patients undergoing other synchronous major surgery. In all, 38 patients had postoperative complications: 28 patients required blood transfusion (four required intervention for their bleeding), five required acute dialysis and three late dialysis. There was a 90% cancer‐specific survival rate at a median follow‐up of 2 years.

CONCLUSIONS

This series confirms the trend towards improved outcomes and decreased complications in OPN at a time when its place is challenged by minimally invasive techniques.
‘Who Did What?’: A Participatory Action Research Project to Increase Group Capacity for Advocacy
Authors: Garcia‐Iriarte E. , Kramer J. C. , Kramer J. M. , Hammel J.
Published: June 2008

Background  This participatory action research (PAR) project involved a collaboration with a self‐advocacy group of people with intellectual disabilities that sought to build group capacity for advocacy.

Materials and Methods  This study used a focus group, sustained participatory engagement and a reflexive process to gather qualitative and quantitative data over 15 months. All methods were adapted to ensure accessibility and to support active participation.

Results  The collaboration generated action products, including tools to support advocacy and an accessible action and reflection process. Research findings suggest that active participation is essential for group control, but alone does not automatically lead to control. The manner in which supports are provided, including member supports, advisor supports, strategy supports and systems supports, influences the extent to which members have a sense of control over decision making and participation and thus, improved capacity for advocacy.

Conclusions  A PAR approach can be used to increase a group’s capacity for advocacy and meaningfully involve self‐advocacy groups in participatory research that leads to change.
Morphology and function of the forelimb in arboreal frogs: specializations for grasping ability?
Authors: Manzano Adriana S. , Abdala Virginia , Herrel Anthony
Published: June 2008

Frogs are characterized by a unique morphology associated with their saltatory lifestyle. Although variation in the form and function of the pelvic girdle and associated appendicular system related to specialized locomotor modes such as swimming or burrowing has been documented, the forelimbs have typically been viewed as relatively unspecialized. Yet, previous authors have noted versatility in forelimb function among arboreal frogs associated with feeding. Here we study the morphology and function of the forelimb and hand during locomotion in two species of arboreal frogs (Litoria caerulea and Phyllomedusa bicolor). Our data show a complex arrangement of the distal forelimb and hand musculature with some notable differences between species. Analyses of high‐speed video and video fluoroscopy recordings show that forelimbs are used in alternating fashion in a diagonal sequence footfall pattern and that the position of the hand is adjusted when walking on substrates of different diameters. Electromyographic recordings show that the flexors of the hand are active during substrate contact, suggesting the use of gripping to generate a stabilizing torque. Measurements of grasping forces in vivo and during stimulation experiments show that both species, are capable of executing a so‐called power grip but also indicates marked differences between species, in the magnitude of forces generated. Stimulation experiments showed an increased control of digit flexion in the more specialized of the two species, allowing it to execute a precision grip paralleled only by that seen in primates.
In Search of Alternatives: The Making of Grassroots Politics and Power in Argentina
Authors: SCHAUMBERG HEIKE
Published: June 2008

This article analyses ethnographically the reconfigurations of the state and relations of power through their dynamic interactions with subaltern alternatives that emerged in the 2001 uprising in Argentina. In this regard, it counters influential interpretations of these events articulated within John Holloway’s framework of ‘anti‐power’, which ignores the reconstruction of the state, and rank and file trade unionism. The article concludes that intensified class and political struggles in the region offer new spaces for contesting hegemonic reinventions of populism and ‘top‐down’ socialism in Latin America.
Disaggregating Corruption: A Comparison of Participation and Perceptions in Latin America with a Focus on Mexico1
Authors: MORRIS STEPHEN D.
Published: June 2008

An abundant empirical literature on corruption relying on survey research has emerged since the mid‐1990s. The predominant line of inquiry concerns perceptions of corruption with respect to institutions and processes. Another, separate line of inquiry that has enjoyed less attention concerns reports about individuals’ participation in corruption. These two dimensions of corruption, however, are typically conflated, leading to error and confusion. This article explores the relationship between the two and seeks to differentiate the two. Using data at the country and individual levels, analysis shows how the two may be only weakly related to one another – though causality remains unclear – and respond to distinct sets of determinants and generate distinct outcomes. The analysis underlines the need to specify the findings in the literature: that the causes and consequences of corruption relate more to ‘perceived’ corruption rather than actual corruption.
US Intervention in Colombia: The Role of Transnational Relations
Authors: AVILÉS WILLIAM
Published: June 2008

In July 2000, US President, Bill Clinton, signed into law the aid package popularly known as ‘Plan Colombia’. Foreign policy analysts examining the ‘US drug war’ have generally focused upon the perceived national security interests of the US state and/or the intermestic nature of domestic politics, or the economic interests of an imperial US state in explaining US drug policy. I posit that the development, initiation and implementation of Plan Colombia cannot solely be understood through these various nation‐state paradigms, as this process was aided by, and facilitated through, an incipient transnational state. The emergence and consolidation into power of a neoliberal state within Colombia, the role of transnational lobbying by US and Colombian policy‐makers, as well as the influence of transnational corporations all played instrumental roles in the initiation, development and implementation of Plan Colombia.
Monte Carlo Inference for State–Space Models of Wild Animal Populations
Authors: Newman Ken B. , Fernández Carmen , Thomas Len , Buckland Stephen T.
Published: June 2008

SummaryWe compare two Monte Carlo (MC) procedures, sequential importance sampling (SIS) and Markov chain Monte Carlo (MCMC), for making Bayesian inferences about the unknown states and parameters of state–space models for animal populations. The procedures were applied to both simulated and real pup count data for the British grey seal metapopulation, as well as to simulated data for a Chinook salmon population. The MCMC implementation was based on tailor‐made proposal distributions combined with analytical integration of some of the states and parameters. SIS was implemented in a more generic fashion. For the same computing time MCMC tended to yield posterior distributions with less MC variation across different runs of the algorithm than the SIS implementation with the exception in the seal model of some states and one of the parameters that mixed quite slowly. The efficiency of the SIS sampler greatly increased by analytically integrating out unknown parameters in the observation model. We consider that a careful implementation of MCMC for cases where data are informative relative to the priors sets the gold standard, but that SIS samplers are a viable alternative that can be programmed more quickly. Our SIS implementation is particularly competitive in situations where the data are relatively uninformative; in other cases, SIS may require substantially more computer power than an efficient implementation of MCMC to achieve the same level of MC error.
Behavioral evidence for a female‐produced sex attractant in Diaphorina citri
Authors: Wenninger Erik J. , Stelinski Lukasz L. , Hall David G.
Published: June 2008

Diaphorina citri Kuwayama (Hemiptera: Psyllidae) is an important worldwide pest of citrus. It vectors three phloem‐restricted bacteria in the genus Candidatus Liberibacter that cause huanglongbing (citrus greening disease). Studies were conducted to examine the behavioral responses of male and female D. citri to conspecifics of the same and opposite sex, with and without associated citrus host plants, in both open‐air arena choice assays and Y‐tube olfactometer assays. Virgin and mated male D. citri colonized citrus plants that were currently or had been previously colonized by virgin or mated female D. citri in greater numbers than control plants without females. However, males or females did not accumulate more on plants colonized by conspecifics of the same sex compared to uninfested plants, and females showed no preference for plants pre‐infested with males compared with uninfested controls. In complementary Y‐tube olfactometer assays, virgin and mated males chose arms with odor sources from mated females compared with blank controls in the absence of associated citrus host plant volatiles. In both behavioral assays, mated female D. citri appeared more attractive than virgin females. The vibrational calling behavior of male D. citri was reduced when males were challenged by the odors of conspecific mated females relative to when males were challenged by the odor of other males. Collectively, our results provide behavioral evidence for a female‐produced volatile sex attractant pheromone in D. citri. Future identification and synthesis of a sex attractant pheromone will be an important contribution to current monitoring and management practices for D. citri.
Longterm findings in peripapillary crescent formation in eyes with mild or moderate myopia
Authors: Nakazawa Mitsuru , Kurotaki Junji , Ruike Hiroshi
Published: June 2008

Purpose:  To describe early changes of optic disc deviation and peripapillary crescent formation in eyes with mild or moderate myopia.

Methods:  We carried out a retrospective review of medical records and fundus photographs. We evaluated serial fundus photographs taken in 10 patients with mild or moderate myopia. We observed longterm changes in optic disc areas by creating video files using these photographs and Photoshop® and Windows Movie Maker® software. The distance between the fovea and the temporal edge of the optic disc was measured in each photograph and any gradual changes in distance between these in the same patient were regarded as representative of optic disc deviation. Correlations between optic disc deviation (0–34.5% disc diameter) and either progression of myopia (− 0.75 D to 6.25 D) or length of follow‐up (21–98 months) were statistically examined.

Results:  On video files, the optic disc appeared to gradually deviate towards the nasal side and the myopic crescent developed gradually in the temporal side of the optic disc in most myopic patients. A significant correlation was found between optic disc deviation and progression of myopia (r2 = 0.61, p < 0.0001), but no correlation was detected between disc deviation and follow‐up period (r2 = 0.055, p = 0.33). As optic disc deviation progressed, the peripapillary crescent became larger.

Conclusions:  The optic disc appears to deviate mostly nasally as myopia progresses and the peripapillary crescent forms as a result of optic disc deviation in eyes with mild or moderate myopia.
The relationship between periodontal condition and serum levels of resistin and adiponectin in elderly Japanese
Authors: Furugen R. , Hayashida H. , Yamaguchi N. , Yoshihara A. , Ogawa H. , Miyazaki H. , Saito T.
Published: June 2008

Background and Objective:  Diabetes and periodontitis are associated with each other. Adipokines, specifically adiponectin and resistin, are secreted from adipocytes and are thought to cause insulin resistance in rodents. Additionally, adiponectin and resistin may play a role in inflammation and immune responses. The aim of this study was to clarify the relationship between serum levels of adipokines and periodontal conditions in elderly Japanese people with and without periodontitis.

Material and Methods:  A total of 158 Japanese men and women (76 years old) with or without periodontitis were selected for the study. Serum adiponectin, resistin, interleukin‐6 (IL‐6) and tumor necrosis factor‐α (TNF‐α) concentrations were compared between subjects with and without periodontitis.

Results:  Serum resistin levels and total leukocyte counts in subjects with periodontitis were higher than in control subjects. No significant differences were observed in adiponectin, IL‐6 and TNF‐α levels between subjects with and without periodontitis. Logistic regression analysis showed that periodontitis with at least one tooth that displayed a probing pocket depth of ≥6 mm was significantly associated with higher serum resistin levels (odds ratio, 2.0; 95% confidence interval, 1.0–4.0). When excluding periodontitis subjects with ≤10% of bleeding on probing and excluding control subjects with >10% bleeding on probing, differences between groups and odds ratio increased. Serum adiponectin tended to decrease in patients with periodontitis, albeit not significantly.

Conclusion:  Increased serum resistin levels were significantly associated with periodontal condition, especially when considering bleeding on probing, in elderly Japanese people. There was also a trend, though non‐significant, toward decreased levels of adiponectin in subjects with periodontitis.
Role of ceramide kinase in peroxisome proliferator‐activated receptor beta‐induced cell survival of mouse keratinocytes
Authors: Tsuji Kiyomi , Mitsutake Susumu , Yokose Urara , Sugiura Masako , Kohama Takafumi , Igarashi Yasuyuki
Published: June 2008

Ceramide (Cer) is known to be a lipid mediator in apoptosis and to have an important role in cell fate, via control of intracellular Cer levels. Recently, ceramide kinase (CerK) was identified as an enzyme that converts Cer to ceramide 1‐phosphate (C1P). We examined potential functions of CerK in the regulation of keratinocyte survival, and the possible involvement of peroxisome proliferator‐activated receptor beta (PPARβ). PPARβ is known to be a nuclear receptor acting as a ligand‐inducible transcription factor and has been implicated in the control of keratinocyte survival. In the mouse keratinocyte cell line SP1, serum starvation induced cell death and the accumulation of intracellular Cer, an apoptotic event. However, apoptosis was inhibited by activation of PPARβ. Interestingly, activation of PPARβ enhanced the mRNA expression of CerK and CerK activity. Furthermore, the cell survival effect of PPARβ was greatly diminished in keratinocytes isolated from CerK‐null mice. Chromatin immunoprecipitation revealed that, in vivo, PPARβ binds to the CerK gene via a sequence located in the first intron. Electrophoretic mobility‐shift assays confirmed that PPARβ associates with this sequence in vitro. These findings indicated that CerK gene expression was directly regulated by PPARβ. In conclusion, our results demonstrate that PPARβ‐mediated upregulation of CerK gene expression is necessary for keratinocyte survival against serum starvation‐induced apoptosis.
Ram pressure stripping in a viscous intracluster medium
Authors: Roediger Elke , Brüggen Marcus
Published: June 2008

In the recent literature, there is circumstantial evidence that the viscosity of the intracluster medium (ICM) may not be too far from the Spitzer value. In this Letter, we present two-dimensional hydrodynamical simulations of ram pressure stripping of disc galaxies in a viscous ICM. The values of viscosity explored range between 0.1 and 1.0 times the Spitzer value. We find that viscosity affects the appearance and the dimensions of the galactic wakes but has very little effect on the evolution of the gas mass of the galaxy.
Ecological Strategies to Promote Healthy Body Image Among Children
Authors: Evans Retta R. , Roy Jane , Geiger Brian F. , Werner Karen A. , Burnett Donna
Published: June 2008

Background:  Personal habits of children and adolescents related to healthy body image (BI) are influenced by various determinants in the micro‐ and macroenvironment. These include attitudes and behaviors about eating; exercise and physical appearance modeled by parents, teachers, and peers; as well as opportunities to learn new habits and social praise for healthy choices. The coordinated school health program (CSHP) is compatible with the 5 levels of an ecological approach to developing new health behaviors.

Methods:  Authors systematically applied the ecological model to all 8 components of coordinated school health. Next, strategies for each of the components were developed using the professional literature as well as author expertise in the areas of health education, exercise science, and dietetics.

Results:  For each strategy, applicable health and physical education standards, as well as goals for each strategy and additional Web resources, were provided to assist educators and administrators in supporting healthy BI among students.

Conclusions:  Educators may effectively use a coordinated approach to guide multiple intervention activities aimed at increasing healthy habits among adolescents and their families. The strength of the CSHP is its collaborative nature with active participation by students, faculty members, family caregivers, agency professionals, community residents, and health care providers.
Linking Global Youth Tobacco Survey 2003 and 2006 Data to Tobacco Control Policy in India
Authors: Sinha Dhirendra Narain , Gupta Prakash C. , Reddy K. Srinath , Prasad Vinayak M. , Rahman Khalilur , Warren Charles W. , Jones Nathan R. , Asma Samira
Published: June 2008

Background: India made 2 important policy statements regarding tobacco control in the past decade. First, the India Tobacco Control Act (ITCA) was signed into law in 2003 with the goal to reduce tobacco consumption and protect citizens from exposure to secondhand smoke (SHS). Second, in 2005, India ratified the World Health Organization Framework Convention on Tobacco Control (WHO FCTC). During this same period, India conducted the Global Youth Tobacco Survey (GYTS) in 2003 and 2006 in an effort to track tobacco use among adolescents.

Methods: The GYTS is a school‐based survey of students aged 13‐15 years. Representative national estimates for India in 2003 and 2006 were used in this study.

Results: In 2006, 3.8% of students currently smoked cigarettes and 11.9% currently used other tobacco products. These rates were not significantly different than those observed in 2003. Over the same period, exposure to SHS at home and in public places significantly decreased, whereas exposure to pro‐tobacco ads on billboards and the ability to purchase cigarettes in a store did not change significantly.

Conclusions: The ITCA and the WHO FCTC have had mixed impacts on the tobacco control effort for adolescents in India. The positive impacts have been the reduction in exposure to SHS, both at home and in public places. The negative impacts are seen with the lack of change in pro‐tobacco advertising and ability to purchase cigarettes in stores. The Government of India needs to consider new and stronger provisions of the ITCA and include strong enforcement measures.
Concurrent Psychosocial Predictors of Sun Safety Among Middle School Youth*
Authors: Andreeva Valentina A. , Reynolds Kim D. , Buller David B. , Chou Chih‐Ping , Yaroch Amy L.
Published: June 2008

Background:  Sun‐induced skin damage, which increases skin cancer risk, is initiated in early life and promoted through later sun exposure patterns. If sun safety determinants are well understood and addressed during the school years, skin cancer incidence might be reduced. This study tested psychosocial influences on youth’s sun safety and assessed their strength within and across gender and ethnicity in a sample of 1782 middle school students.

Methods:  Predictors included sunburn and skin cancer knowledge, tanning attitudes, peer norms, and barriers regarding sun exposure and were assessed with a self‐administered, validated questionnaire. The hypothesized relationships were tested with structural equation models and confirmed with multilevel regression.

Results:  Across gender and ethnicity, knowledge emerged as an important sun safety predictor with both direct and indirect effects mediated through tanning attitudes. The relationship with barriers did not reach statistical significance within any of the subgroups, possibly due to measurement limitations. An indirect effect of peer norms on sun safety, mediated through tanning attitudes, was confirmed only among girls. Also, an indication that peer norms operate differently within the ethnic groups was found, since this predictor had a statistically significantly stronger relationship with sun safety among non‐Hispanics.

Conclusions:  Youth’s sun safety is a multifactorial practice, partially determined by ethnicity‐ and gender‐based standards. In order to ensure health‐promoting school environments, needed are multicomponent programs where peer norms and knowledge are salient and where sun safety is addressed individually and together with other health risk behaviors.
Species richness and adaptive capacity in animal communities: lessons from China
Authors: MACKINNON John
Published: June 2008

Climate change is already threatening the long‐term viability of many important protected areas, and as global warming accelerates this will increase. Lowered water tables, melting permafrost, changing vegetation zones, combined with the fragmentary distribution of wilderness areas, will cause a wave of local extinctions as species fail to adapt to changing conditions in time or fail to move as climate zones advance across the face of the continents. Ecologists can predict and even model likely scenarios, but can we do anything to help safeguard valuable biodiversity or must we passively document Earth's changes and accept these losses? Studies of the extraordinary species richness of the Hengduan Mountains and the Qionglai Mountain ranges of South‐West China and of the Changbaishan Mountains in North‐East China give us some optimism. This paper provides an explanation for the high species richness in these ranges and identifies design principles that can be used in the selection of protected areas or in the revision of existing protected area boundaries to enhance their ecological resilience and allow them to maintain higher levels of biological diversity under conditions of climate change or other disturbance.
Differentiation in seed hoarding among three sympatric rodent species in a warm temperate forest
Authors: LU Jiqi , ZHANG Zhibin
Published: June 2008

Although seed hoarding by rodents has been extensively studied, differentiation in seed‐hoarding behaviors among sympatric rodent species has not been well investigated. Using semi‐natural enclosures, we demonstrated that three sympatric rodent species showed clear differentiation in food selection, scatter versus larder hoarding behaviors and eating behaviors when offered seeds of four plant species from a warm temperate forest in northern China. The large field mouse Apodemus peninsulae preferred seeds of wild apricot (Prunus armeniaca) and Liaodong oak (Quercus liaotungensis), whereas the Chinese white‐bellied rat Niviventor confucianus preferred seeds of cultivated walnut and Liaodong oak, and the David's rock squirrel Sciurotamias davidianus preferred seeds of cultivated walnut, wild apricot and Liaodong oak. All three rodents showed larder hoarding of seeds from all four plant species, but the large field mouse showed scatter hoarding of wild apricot, and the David's rock squirrel showed scatter hoarding of Liaodong oak and wild walnut. Acorns of Liaodong oak, which have a soft seed hull, were more often eaten in situ, whereas wild walnuts, which have a hard seed hull and more tannin, were less hoarded by all rodent species. Differentiation in the scatter versus larder hoarding behaviors of sympatric rodent species suggests that sympatric rodents play different roles in the regeneration of different sympatric plant species.
What is your diagnosis? Biopsy impression smear of a hepatic mass in a yearling Thoroughbred filly
Authors: Gold Jenifer R. , Warren Amy L. , French Tracy W. , Stokol Tracy
Published: June 2008

Abstract:A 1‐year‐old Thoroughbred filly was presented to the Cornell University Hospital for Animals with a 10‐day history of fever, diarrhea, inappetance, and hypodipsia. Clinical pathology abnormalities found by the referring veterinarian included erythrocytosis, hyperproteinemia, and increased serum γ‐glutamyltransferase and lactate dehydrogenase activities. At Cornell University, the laboratory abnormalities were confirmed and also included thrombocytosis and hypoglycemia. Erythrocytosis persisted despite vigorous fluid therapy. Ultrasound examination revealed an extremely enlarged liver with abnormal echogenicity and a 21 × 25‐cm hepatic mass with varied echogenicity. Imprints of an ultrasound‐guided biopsy of the mass revealed a neoplastic epithelial population of uncertain origin, although the cells did not resemble hepatocytes. Together with the presenting signs, signalment, ultrasonographic findings, and persistent erythrocytosis, the cytologic findings were considered to be most consistent with hepatoblastoma. Histopathologic examination of the mass at necropsy confirmed the diagnosis and findings also included bone marrow erythroid hyperplasia. Serum erythropoietin concentration was 28.0 mU/mL (reference interval 1.0–11.8 mU/mL), supporting erythropoietin production by the tumor and secondary inappropriate erythrocytosis. To our knowledge, this report is the first to document secondary erythrocytosis with increased erythropoietin concentration in a horse with hepatoblastoma, and also the first to describe the cytopathologic features of this rare tumor.
Dynamic Response Studies of Piping-Support Systems
Authors: Chiba T. , Koyanagi R.
Published: June 2008

Considering the effect of the interaction between piping and support systems in the piping design is a more integrated approach to improve the reliability of piping systems. So, it is important to clarify the dynamic characteristics of the piping and the restraint structure during the seismic events. It may be desirable to investigate the effect of the gap on the response and the local stress of the piping systems. The dynamic characteristics of a simplified piping model with gaps was investigated by the tests and the analysis. Three-dimensional piping model test was performed to estimate the effect of the gap on the response of the piping system. It can be found that the local stress and the stiffness of the piping and the restraint structure under the seismic loadings should be considered in the seismic design. The gap size was not so effective on the response of the 3-dimensional piping system in the high-level response.
Flow-Induced Vibration of Rod Arrays in a Jet Flow
Authors: Lee H. , Chang Y. B.
Published: June 2008

Flow-induced vibration of rod arrays in a jet flow was studied experimentally. The rod arrays tested were on square layout with a pitch-to-diameter ratio of 1.32. The rods were found to vibrate with large whirling trajectories when the jet velocity exceeds a critical value. The effects of axial flow velocity and stand-off distance of the rod array from jet exit were also investigated. A design guide for rod arrays subjected to a jet flow is proposed.
An Interpretation of Axial Creep-Fatigue Damage Interaction in Type 316 Stainless Steel (Survey Paper)
Authors: Zamrik S. Y.
Published: June 2008

Creep-fatigue interaction and its effect on damage of components in service have been a major concern to analysts. To deal with this problem, several criteria have been proposed and used, such as: cycle-time fraction summation rule, strain limit, fracture maps where damage mechanisms are based on crack initiation or propagation, and ductility exhaustion. These concepts are reviewed in this paper so that one can interpret the damage mechanisms caused by creep and by fatigue. If a long period of dwell-time at elevated temperature is imposed on a component under strain conditions, stress relaxation occurs. Relaxation data can be used, for example, in austenitic steels, in predicting creep stages; however, interpretation of data obtained from such tests could be misleading in assessing damage. An example is given for life prediction on the basis of two selected criteria: the fraction rule and ductility exhaustion.
Thermoelastoplastic and Residual Stresses in a Hollow Cylinder With Temperature-Dependent Properties
Authors: Jahanian S. , Sabbaghian M.
Published: June 2008

Determination of residual stresses and the positive or negative effect that they may have on the component is an important consideration in design. Unexpected failure of components, latter determined to be attributable to residual stress, is not uncommon. In this paper, a theoretical study of the stresses in a long hollow circular cylinder subjected to rapid cooling of the exterior surface is presented. A quasi-static uncoupled thermoelastoplastic analysis, based on incremental theory of plasticity, is developed and a numerical procedure for successive approximation is formulated. For this analysis, it is assumed that the material has temperature-dependent properties and is characterized by linear strain hardening. The thermoelastoplastic and residual stress distributions are discussed in detail. The results are compared with related published work where a reasonable agreement is observed.
Long-Term Creep Curve Prediction Based on the Modified θ
Projection Concept
Authors: Maruyama K. , Tanaka C. , Oikawa H.
Published: June 2008

A modified θ projection concept was applied to CrMoV ferritic steels to predict long-term creep curves. The concept was successful in predicting long-term curves up to rupture. Physical basis of a constitutive equation for the concept was examined in terms of temperature dependence of its rate constant.
A Finite Element Technique for Limit Analysis of
Structures
Authors: Berak E. G. , Gerdeen J. C.
Published: June 2008

Limit analysis provides an alternative to incremental elastic-plastic analysis for determining a limit load. The limit load is obtained from the lower and upper-bound theorems. These theorems, which are based on variational principles, establish the static and kinematic methods, respectively, and are particularly attractive for finite element implementation. A finite element approach using the definition of the p-norm is developed for calculating upper and lower bounds of the limit load multiplier for two-dimensional, rigid perfectly plastic structures which obey the von Mises yield criterion. Displacement and equilibrium building block quadrilateral elements are used in these dual upper and lower-bound formulations, respectively. The nonlinear finite element equations are transformed into systems of linear algebraic equations during the iteration process, and the solution vectors are determined using a frontal equation solver. The upper and lower-bound solutions are obtained in a reasonable number of iteration steps, and provide a good estimate of the limit load multiplier. Numerical results are provided to demonstrate this finite element procedure. In addition, this procedure is particularly applicable to the solution of complex problems using parallel processing on a supercomputer.