bluuebunny/crossref_metadata_2025 huggingface dataset:
Impersonal null‐subjects in Icelandic and elsewhere*
Authors: Sigurðsson Halldór Ármann , Egerland Verner
Published: March 2009

Abstract. This paper discusses impersonal null‐subjects in Icelandic and elsewhere. Despite the fact that the interpretation of Icelandic impersonal null‐subjects obeys restrictions similar to those observed for overt impersonal subject pronouns in various languages, they cannot be analyzed as lexical pronouns, deleted in PF. Rather, it is argued, impersonal null‐subjects are constructed in syntax, by combination (merger) of abstract features. In general, it seems that pronouns, silent and overt, are PF representations of complex syntactic structures, rather than tokens for discrete terminal nodes. In addition, the paper discusses the cross‐linguistic distribution and typology of impersonal null‐subjects.
RISK AND UNCERTAINTY IN CENTRAL BANK SIGNALS: AN ANALYSIS OF MONETARY POLICY COMMITTEE MINUTES
Authors: Dow Sheila , Klaes Matthias , Montagnoli Alberto
Published: March 2009

This paper considers the signalling aspect of monetary policy. We introduce a heuristic framework for the study of signal uncertainty, and use this to analyse the signal uncertainty implicit in the communications of the Bank of England's Monetary Policy Committee (MPC). Our findings suggest that frequencies of key terms expressing signal uncertainty in MPC minutes may either reflect the degree of confidence implicit in MPC deliberations, or offer evidence for the presence of an irreducible kind of signal uncertainty that shows up as white noise, casting doubt on the soundness of the various qualitative uncertainty indices found in the literature.
BUYING VERSUS HIRING—AN INDIRECT EVOLUTIONARY APPROACH
Authors: Berninghaus Siegfried K. , Güth Werner
Published: March 2009

On a symmetric homogeneous oligopoly market with stochastic demand, firms can either hire employees or buy their labor input on a competitive labor market. Whereas the wage of hired labor does not depend on the realization of stochastic demand, the price of ‘bought’ labor reacts positively to product demand. We derive the equilibrium price vector to define an evolutionary process, assuming that the number of hiring firms increases when they earn more than buying firms. We then derive and discuss the stationary distribution of this stochastic adaptation process.
An Ounce of Prevention: A New Look at the Manchurian Incident
Authors: Conroy Hilary , Takemoto Toru
Published: March 2009

This article is scheduled for future publication in a testimonial volume honoringthe retirement of Professor Woodbridge Bingham of the University of California, Berkeley.
THE WOMAN'S PEACE PARTY AND QUESTIONS OF GENDER SEPARATISM
Authors: Craig John M.
Published: March 2009

The Woman's Peace Party (WPP), founded in 1915, represented the first national separate women's peace society established in the United States. Some of its principal founders, though, were uncertain initially about the idea of creating a gender‐exclusive group. Their uneasiness did not prevent the formation of the WPP, but the issue failed to go away. Rather, the separatist question affected WPP actions throughout World War I. Of all the WPP leaders who struggled with the separateness issue, the one who faced the dilemma most directly was Crystal Eastman, the guiding force of the organization's New York City branch. Two years after the WPP was founded, Eastman criticized the group for failing to “capitalize on women's greater regard for life.” She moved the New York City branch in this direction, but the WPP in general failed to make capital out of the fact that it expressed a woman's protest.
PEACE, SECURITY, AND THE MOVEMENT OF PEOPLE
Authors: Ferris Elizabeth G.
Published: March 2009

Western governments are increasingly seeing the issues of refugees and migrants in terms of national security. This article surveys the changing paradigms used to understand and respond to forced migration, including humanitarian/emergency approaches, foreign policy, human rights, development, and the emerging national security paradigm. The article explains some of the reasons for the emergence of this security paradigm and outlines the security concerns of host governments. The consequences of a focus on security are examined and the alternative of an approach based on common security is explored. The article concludes that an emphasis on common security and peace offers many advantages in dealing with both the causes and the consequences of forced migration.
ALTERNATIVE DEVELOPMENT STRATEGIES AND REGENERATION OF SOCIAL SPACE FOR HUMAN DEVELOPMENT
Authors: Jeong Ho‐Won
Published: March 2009

This article examines the role of grass‐roots efforts in the promotion of alternative development strategies and the relationship between participatory development and social change. The main themes of this study are related to survival strategies that may be useful for the marginalized along the periphery of the global political economy. In the article, human development is understood in terms of ordinary people's control over everyday life, and this is viewed as an important means to regenerate people's power and provide social space for an indigenous problem‐solving process. Human development is closely linked to efforts to challenge economic exploitation and marginalization.
ARMS CONTROL NEGOTIATIONS IN THE MIDDLE EAST The Issue of Sequencing
Authors: Solingen Etel
Published: March 2009

This article takes stock of the ongoing negotiations on arms control and regional security in the context of the multilateral peace talks on the Middle East. It examines the background conditions that made these negotiations possible and the problem of designing the right sequence within which different issues are addressed. The author reviews the role of confidence‐building measures in the early stages of arms control negotiations. Next, it is explored why certain sequences may help the current partners to the negotiations in two ways. First, they may induce those countries that have not yet joined the multilateral negotiations to do so. Second, agreeing on the right sequence may secure domestic support for arms control and the peace process as a whole.
UNDERSTANDING THE CONCEPT “PEACE” A Search for Common Ground
Authors: Rinehart Milton
Published: March 2009

From the premise that how we make peace is determined by how we define peace, this article attempts to add some clarity to the conceprualizations of peace and there by to peace research and practice. It identifies two basic orientations or paradigms of peace and elements of the worldviews that underlie each paradigm, drawing on contemporary conceptualizations and on philosophical and historical works. The two paradigms are contrasted with each other, and they are viewed as locations on a continuum of peace understanding that shows a way for peace researchers, practitioners, activists, and educators to communicate about peace. This article attempts to establish some common conceptual ground to enable all those concerned about peace to work together more effectively.
SOME IMPLICATIONS OF POSTMODERNISM FOR THE FIELD OF PEACE STUDIES
Authors: Mason Gregory H.
Published: March 2009

Postmodernism is a useful tool for expanding our conceptualization and application of peace studies. In particular, as a system of ideas that stresses the unavoidably ethnocentric and normative character of Western assumptions about conflict resolution, postmodernism offers us a means to adjust planning and expectations to different societal conditions. Cultural differences are neither trivial nor peripheral. In peace studies, just as in the conventional political arena, Americans need to guard against what Noam Chomsky has called the “tradition of naivete and self‐righteousness that disfigures our intellectual history.”
TEACHING THE VIETNAM WAR IN THE 1990s: A Personal View
Authors: Taylor Sandra C.
Published: March 2009

This essay offers a brief survey of sources available for classroom use in teaching the American experience in Vietnam, adjusted for students of the 1990s. The author is particularly concerned with placing the Vietnam War in the context of Asian history and culture. Attention is paid to useful new histories and novels as well as materials available on video cassette. The author discusses her own experience with producing video materials for the classroom.
THE GREATER KENT STATE ERA, 1968–1970 Legacies of Student Rebellions and State Repression
Authors: Hine Darlene Clark
Published: March 2009

This article articulates the personal, professional, and systemic legacies of the Greater Kent State Era, a time of dramatic upheaval across America's campuses. The author was a graduate student at Kent State in 1970 and recounts her personal reaction to the shootings of May 4, including “library exile,” as well as the era's legacy regarding Black Studies, Women's Studies, and Ethnic Studies‐as measured in the scholarship produced by the Greater Kent Slate generation.
MICHAEL HARRINGTON AND THE VIETNAM WAR: THE FAILURE OF ANTI‐STALINISM IN THE 1960S
Authors: Isserman Maurice
Published: March 2009

Michael Harrington criticized the antiwar movement of the 1960s for failing to adopt an “anti‐Stalinist” perspective regarding the Vietnam War, i.e., a viewpoint that would be equally critical of both sides in the conflict. The fact that Harrington's perspective won few adherents in the antiwar struggle was a product in significant measure of the failures of the anti‐Stalinists themselves. The dogmatic and inflexible sectarianism of the dominant faction within the Socialist Party left it isolated and irrelevant, as some of its own supporters, and eventually Harrington himself, realized. In the aftermath of the 1960s, Harrington came to be a critic of the very politics he had espoused during the Vietnam War. However, by then, it was too late for him to recapture the position of political and moral authority he had enjoyed in the left at the start of the sixties.
Activation of the Brainstem but not of the Hypothalamus in Hemicrania Continua without Autonomic Symptoms
Authors: Irimia P , Arbi J , Prieto E , Fernández-Torrón R , Martínez-Vila E
Published: March 2009

A 64-year-old woman presented with a 6-month history of right-sided continuous headache, without autonomic symptoms and complete response to indomethacin. Clinical examination and structural brain imaging were normal. A diagnosis of hemicrania continua (HC) was made. We sought to determine the brain structures active during the pain in a patient who met all of the diagnostic criteria for HC with the exception of autonomic symptoms. A brain positron emission tomography study was performed during pain, and completely pain-free after indomethacin administration. Comparing the pain with pain-free states, the region of the dorsal pons was significantly activated. There was no activation in the hypothalamus, as previously reported in HC with autonomic symptoms. Although definitive conclusions can not be drawn from a single observation, the lack of autonomic symptoms along with the absence of hypothalamic activation suggests that the clinical presentation may predict the pattern of brain activation in primary headache syndromes.
Rational Choice, Religion, and the Marketplace: Where Does Adam Smith Fit In?
Authors: Peterson Scot M.
Published: March 2009

Rational choice theorists of religion have assumed that Adam Smith's Wealth of Nations advocates a free market in religion, which, they argue, leads to increased religious vitality. In fact, while Smith opposed direct government subsidies for religion and argued that a free market was the first‐best solution, as a second‐best policy he advocated religious regulation, including state‐appointed clergy and the reduction of clergy income. Smith's rational choice approach to religion, which springs from his understanding of public goods, externalities and the need for civil peace, and government stability, can still provide direction for social scientific research, but it does not always support a policy of religious free markets.
Visions of the future: social processes and terrorism in Europe1
Authors: Reshetnikov Mikhail
Published: March 2009

Abstract:  When we think of terrorism, we tend to think of Islamic terrorism but in fact most of the violent happenings in our societies are caused by ‘domestic terrorism’ and it has been suggested by authors such as Twemlow that there is a developmental continuum between social activism and terrorism. The generalized rise in what the author terms ‘a terrorist worldview’ has been linked to many different social, political, economic and psychological conflicts but the present paper suggests that this is not sufficient and that in order to understand it it is necessary to take into consideration certain processes in contemporary civilization. At present, I am suggesting that Western civilization is characterized by the generalized breakdown of values and of signifying structures and by the gradual weakening of the models of state power and institutions that previously guaranteed the unity and security of our societies. The result is a crisis of identity which is particularly evident among the youth of today and when this is exasperated by the failure of authority to provide an adequate explanatory system of contemporary reality and by the tendency to resort to repressive mechanisms, all too often the result is the degeneration of social activism into social violence. It is becoming urgent that our societies reflect on more efficient ways of preventing social activism degenerating into terrorism, both internationally and domestically.
Insurance Disruption due to Spousal Medicare Transitions: Implications for Access to Care and Health Care Utilization for Women Approaching Age 65
Authors: Schumacher Jessica R. , Smith Maureen A. , Liou Jinn‐Ing , Pandhi Nancy
Published: March 2009

Objective. To assess whether a husband's Medicare transition leads to insurance disruptions for his wife that impact her perceived access to care, health care utilization, or health status.

Data Sources/Study Setting. Respondents were married women under age 65 from the 2003–2005 round of the Wisconsin Longitudinal Study (N=655).

Study Design. Instrumental variable (IV) linear and IV‐probit analyses provided unbiased estimates of the effect of an insurance disruption on study outcomes. The instrument was the husband's age: (1) women with husbands who transitioned to Medicare within the previous year (age 65–66); (2) women with husbands who did not transition (60<age<65).

Data Collection/Extraction Methods. Respondents were surveyed via telephone and mail.

Principal Findings. After adjustment, women who experienced an insurance disruption due to their husband's Medicare transition had a greater probability of experiencing a change in usual clinic/provider (71 percent), delaying filling or taking fewer medications than prescribed because of cost (75 percent), going to the emergency room (52 percent), and had lower average mental health scores than women who did not experience an insurance disruption.

Conclusions. Despite consistent insurance coverage, the insurance disruption that accompanies a spouse's Medicare transition has adverse access and health care utilization consequences for women.
Retention, Learning by Doing, and Performance in Emergency Medical Services
Authors: David Guy , Brachet Tanguy
Published: March 2009

Objectives. To examine the strength of the volume–outcome relationship among paramedics, a group of providers that has not been previously studied in this context. By identifying the effects of individual learning on performance, we also assess the value of paramedics' retention. The prehospital emergency medical services (EMS) setting allows us to interpret any volume–outcome relationship as learning by doing, uncontaminated by reputation‐based referrals because ambulance units are dispatched based on proximity.

Data Sources. Incident‐level EMS data spanning 1991 to 2005 from the Mississippi Emergency Medical Services Information System collected by the Mississippi Department of Health.

Research Design. Using linear and quantile methods with and without provider fixed effects, we estimate the relationship between experience accumulation and performance using the universe of trauma incidents involving injured patients (including motor vehicle crashes, falls, stabbings, and shootings).

Principal Findings. We find that greater individual volume is robustly related to improved performance. In addition, we find that the benefit of learning operates through both recent and past experiences, accrues differentially across tenure groups, and operates on both mean performance and the upper quantiles of the performance distribution.

Conclusions. Persistent past and current volume effects suggest that policy and managerial implications in EMS should be directed at retention efforts to take advantage of individual learning by paramedics.
Changing Perceptions of Change: The Role of Scientists inTamarixand River Management
Authors: Stromberg Juliet C. , Chew Matthew K. , Nagler Pamela L. , Glenn Edward P.
Published: March 2009

Initially introduced to western United States to provide ecosystem services such as erosion control,Tamarixby the mid‐1900s had became vilified as a profligate waster of water. This large shrub continues, today, to be indicted for various presumed environmental and economic costs, and millions of dollars are expended on its eradication. In this review, we examine the role of scientists in driving changes in perceptions ofTamarixfrom valuable import to vilified invader and (in some instances) back to a productive member of riparian plant communities. Scientists over the years have sustained a negative perception ofTamarixby, among other things, (1) citing outmoded sources; (2) inferring causation from correlative studies; (3) applying conclusions beyond the scope (domain) of the studies; and (4) emphasizing findings that present the species as an extreme or unnatural agent of change. Recent research is challenging the prevailing dogma regardingTamarix’s role in ecosystem function and habitat degradation and many scientists now recommend management shifts from “pest plant” eradication to systemic, process‐based restoration. However, prejudice against this and other non‐native species persists. To further close the gap between science and management, it is important for scientists to strive to (1) cite sources appropriately; (2) avoid reflexive antiexotic bias; (3) avoid war‐based and pestilence‐based terminology; (4) heed the levels of certainty and the environmental domain of studies; (5) maintain up‐to‐date information on educational Web sites; and (6) prior to undertaking restoration or management actions, conduct a thorough and critical review of the literature.
Evaluation of renal function in children with mitochondrial respiratory chain complex defect: usefulness of cystatin C
Authors: Lee Soon Min , Kim Ji Hong , Lee Young Mock , Lee Joon Soo , Kim Heung Dong
Published: March 2009

Aim: Mitochondrial disorders with respiratory chain complex defect are known to show a broad spectrum of clinical phenotypes, though their contribution to renal disease has not received much attention. The aim of this study was to evaluate renal function using different markers of the glomerular filtration rate (GFR) in children with mitochondrial respiratory chain complex (MRC) defects.

Methods: Twenty‐two patients with MRC I defect confirmed by biochemical enzyme assays using muscle tissue, were evaluated for renal function with diethylenetriaminepentaacetic acid (DTPA) renal scintigraphy, urine creatinine clearance, serum creatinine (Scr) and cystatin C (Cys C) levels.

Results: All patients showed lower levels within normal range of Scr (0.4–0.7 mg/dL, mean 0.47 mg/dL), and with no significant correlation with DTPA–GFR. Cys C showed significant correlation with DTPA–GFR (p < 0.01) providing higher diagnostic accuracy than creatinine in patients with MRC defect.

Conclusion: In mitochondrial disorder with MRC defect, Scr could not fully reflect renal function due to the relatively small body mass of patients. Considering the limited clinical availability of DTPA renal scintigraphy, Cys C should be taken as the first step to evaluate GFR in mitochondrial disorders.
Ca2+/H+ antiporter‐like activity of human recombinant Bax inhibitor‐1 reconstituted into liposomes
Authors: Ahn Taeho , Yun Chul‐Ho , Chae Ho Zoon , Kim Hyung‐Ryong , Chae Han‐Jung
Published: March 2009

We investigated the functional activity of recombinant Bax inhibitor‐1 reconstituted into liposomes. When proteoliposomes were suspended in acidic solutions, encapsulated Ca2+ was released from the membranes, as previously suggested [Kim HR, Lee GH, Ha KC, Ahn T, Moon JY, Lee BJ, Cho SG, Kim S, Seo YR, Shin YJ et al. (2008) J Biol Chem283, 15946–15955]. Concomitantly, proton ions were internalized when assayed using the time‐dependent change in the fluorescence of the pH‐sensitive dye oxonol V entrapped in the proteoliposomes. The influx of proton ions was confirmed by observing tritium accumulation in the membranes. However, the external acidity of the membranes per se did not induce proton ion influx without internalized Ca2+. These results suggest that reconstituted Bax inhibitor‐1 has a Ca2+/H+ antiporter‐like activity.
Antinociceptive Properties of the Hydroalcoholic Extract, Fractions and Compounds Obtained from the Aerial Parts ofBaccharis illinitaDC in Mice
Authors: Freitas Cristina Setim , Baggio Cristiane Hatsuko , Dos Santos Ana Cristina , Mayer Bárbara , Twardowschy André , Luiz Ana Paula , Marcon Rodrigo , Soldi Cristian , Pizzolatti Moacir G. , Dos Santos Elide Pereira , Marques Maria Consuelo Andrade , Santos Adair R. S.
Published: March 2009

Abstract: The present study assessed the possible antinociceptive action of the hydroalcoholic extract, fractions and pure compounds obtained from the aerial parts ofBaccharis illinitaDC (Asteraceae) in behavioural models of chemical nociception in mice. The hydroalcoholic extract and fractions (hexane and aqueous but not EtOAc fraction) obtained fromB. illinita(30–1000 mg/kg orally) produced a dose‐related inhibition of the acetic acid‐induced nociceptive response. However, the hexane fraction was more potent than the hydroalcoholic extract and the aqueous fraction. The hexane fraction derivatives baurenol, α‐spinasterol and oleanolic acid (0.00001–10 mg/kg intraperitoneally) also caused potent inhibition of acetic acid‐induced pain. The hexane fraction (300–1000 mg/kg orally) produced inhibition of both phases of formalin‐induced pain. Moreover, the hexane fraction (30–600 mg/kg orally) also caused a dose‐dependent inhibition of glutamate‐induced pain. Nevertheless, the hexane fraction only at the dose of 300 mg/kg orally, produced partial inhibition of the paw oedema caused by carrageenan. Furthermore, the hexane fraction (300 mg/kg orally) caused inhibition of the nociceptive response induced by intrathecal injection ofN‐methyl‐d‐aspartic acid, α‐amino‐3‐hydroxy‐5‐methyl‐4‐isoxazolepropionic acid, tumour necrosis factor‐α and interleukin‐1β. In contrast, the hexane fraction did not affect the biting response induced by the metabotropic or ionotropic glutamatergic receptor agonist (±)‐1‐aminocyclopentane‐trans‐1,3‐dicarboxylic acid and kainate, respectively. In addition, the antinociception caused by the hexane fraction (300 mg/kg orally) in the acetic acid test was not affected by intraperitoneal treatment of mice with naloxone (a non‐selective opioid receptor antagonist). The precise mechanism responsible for the antinociceptive effect of the hexane fraction remains unclear, but appears to be partly associated with an inhibition of glutamatergic transmission and an inhibition of pathways dependent on pro‐inflammatory cytokines. Finally, baurenol, α‐spinasterol and oleanolic acid have an important role in the antinociceptive effects of the hexane fraction. Moreover, the antinociceptive action demonstrated in the present study supports the ethnomedical uses of this plant.
Influence of seed location and planting depth on seedling establishment in cattle dungpats
Authors: Gökbulak Ferhat
Published: March 2009

This study was conducted to investigate the effects of seed location in dungpats on emergence, shoot and root development and survival of seedlings of bluebunch wheatgrass (Psuedoroegneria spicata [Pursh] A. Love) and Sandberg bluegrass (Poa secunda L.) and to know the potential of using fecal seeding as an alternative revegetation strategy on rangelands. Artificially‐prepared 4‐cm thick dungpats of 20 cm diameter were placed on a sandy loam soil in large plastic containers. Animals were fed 60 000 seeds of each grass species and passed seeds were recovered from dung collected at the time of maximum seed passage. Pre‐germinated undamaged passed seeds of each species were planted separately in the center and periphery of the dungpats at heights of 0.5, 2.0 and 3.5 cm from the bottom of the dungpats. Seedlings were harvested 10, 30 and 60 days after planting and measured for shoot height, number of leaves and tillers and root length. Seedling emergence, survival and total root length were greatest when seeds of both species were planted in the periphery of the dungpats at a height of 0.5 cm from the bottom of the dungpats. Seedling emergence and survival were greater for bluebunch wheatgrass than for Sandberg bluegrass. Seed location did not have an effect on height or tiller growth of seedlings for either species.
Ultra faint dwarfs: probing early cosmic star formation
Authors: Salvadori Stefania , Ferrara Andrea
Published: March 2009

We investigate the nature of the newly discovered Ultra Faint dwarf spheroidal galaxies (UF dSphs) in a general cosmological context simultaneously accounting for various ‘classical’ dSphs and Milky Way properties including their metallicity distribution function (MDF). To this aim, we extend the merger tree approach previously developed to include the presence of star-forming minihaloes, and a heuristic prescription for radiative feedback. The model successfully reproduces both the observed [Fe/H]–luminosity relation and the mean MDF of UFs. In this picture, UFs are the oldest, most dark matter-dominated (M/L > 100) dSphs with a total mass M = 107−8M⊙; they are leftovers of H2-cooling minihaloes formed at z > 8.5, that is before reionization. Their MDF is broader (because of a more prolonged star formation) and shifted towards lower [Fe/H] (as a result of a lower gas metallicity at the time of formation) than that of classical dSphs. These systems are very ineffectively star-forming, turning into stars by z = 0 only <3 per cent of the potentially available baryons. We provide a useful fit for the star formation efficiency of dSphs.
CO line emission in the halo of a radio galaxy at z = 2.6
Authors: Nesvadba N. P. H. , Neri R. , De Breuck C. , Lehnert M. D. , Downes D. , Walter F. , Omont A. , Boulanger F. , Seymour N.
Published: March 2009

We report the detection of luminous CO(3–2) line emission in the halo of the z = 2.6 radio galaxy (HzRG) TXS0828+193, which has no detected counterpart at optical to mid-infrared wavelengths implying a stellar mass ≲ few ×109 M⊙ and relatively low star formation rates. With the IRAM Plateau de Bure Interferometer (PdBI), we find two CO emission-line components at the same position at ∼80 kpc distance from the HzRG along the axis of the radio jet, with different blueshifts of few 100 km s−1 relative to the HzRG and a total luminosity of ∼2 × 1010 K km s−1 pc2 detected at a total significance of ∼8σ. HzRGs have significant galaxy overdensities and extended haloes of metal-enriched gas often with embedded clouds or filaments of denser material, and likely trace very massive dark matter haloes. The CO emission may be associated with a gas-rich, low-mass satellite galaxy with very little ongoing star formation, in contrast to all previous CO detections of galaxies at similar redshifts. Alternatively, the CO may be related to a gas cloud or filament and perhaps jet-induced gas cooling in the outer halo, somewhat in analogy with extended CO emission found in low-redshift galaxy clusters.
Rupture and Fusion in the Approach to Myth: Situating Myth Analysis Between Philosophy, Poetics and Long‐Range Historical Reconstruction
Authors: Van Binsbergen Wim
Published: March 2009

On the basis of my engagement with myth over the decades, the present paper seeks to present some ‘prolegomena’ to the study of myth today. It does so, in the first place, by a short overview of philosophical contributions and implications of the study of myth. After formulating and discussing a possible definition of myth, the argument focuses on two complementary perspectives in the scholarly approach to myth: the objectifying perspective of rupture versus the participatory and identifying perspective of fusion. After indicating the pros and cons of both, and giving an example (notably, the ‘hero fights monster’ mytheme) of extensive continuity in myth through space and time, the paper concludes with a summary of the main results of the author's current long‐range comparative research into leopard and leopard‐skin symbolism, which is informed by loosely interlocking mythical complexes extending all across the Old World and part of the New World, over a time span from the Upper Palaeolithic to the present.
Numerical Study of Thermally Targeted Liposomal Drug Delivery in Tumor
Authors: Zhang Aili , Mi Xipeng , Yang Geer , Xu Lisa X.
Published: March 2009

The efficacy of cancer chemotherapy can be greatly enhanced by thermally targeted nanoparticle liposome drug delivery system. A new theoretical model coupling heat and mass transfer has been developed to study the spatial and transient drug distributions. In this model, the influence of tumor cell apoptosis and necrosis in drug transport is also considered, in addition to the tumor microvasculature permeability to nanoliposomes. The model predictions agree well with our previous experimental results, and it has been used to simulate the nanoparticle drug distribution in the tumor under hyperthermic conditions. Results show that hyperthermia alone only enhances drug accumulation in the periphery of a tumor with 1 cm in radius, and the tumor cells in the central region are hardly damaged due to poor drug diffusion. Apoptosis or necrosis of the tumor cells could significantly influence the drug penetration and should be accounted for in drug diffusion modeling to accurately predict the therapeutic effect. Simulation study on the combined radio frequency ablation and liposomal doxorubicin delivery shows more effective treatment outcome, especially for larger tumors. The present model can be used to predict the treatment outcome and optimize the clinical protocol.
Numerical and Experimental Investigations of the Cavitating Flow in a Centrifugal Pump Impeller
Authors: Frobenius Moritz , Schilling Rudolf , Friedrichs Jens , Kosyna Gu¨nter
Published: March 2009

This paper presents numerical simulations and experimental investigations of the cavitating flow through a centrifugal pump impeller of low specific speed. The experimental research was carried out at the Pfleiderer-Institute of the Technical University of Braunschweig, while the numerical simulations were performed at the Institute for Hydraulic Machinery and Plants at the Technical University of Munich (LHM). The cavitation model used is based on bubble dynamics and is able to describe the complicated and transient growth and collapse of the cavitation bubbles. The model has been implemented in the 3D CFD-code CNS3D developed at the LHM. The CNS3D-code has been applied to simulate the cavitating flow through a centrifugal pump impeller. The computed pump head, incipient NPSH and three-percent head drop are compared to the experimental data. Also the pressure distributions measured on the blades are compared with the computed ones. Finally, the numerically investigated void fraction distributions are shown in comparison with pictures of the cavitation zones on the blade.
Time-Dependent Optimal Perturbations for the Algebraic Instability in the Nonlinear Regime
Authors: Zuccher Simone , Luchini Paolo
Published: March 2009

The aim of the present study is to extend the linear unsteady optimal-perturbation analysis of (Luchini 2000) to the nonlinear regime. In order to account for the nonlinear interactions, a Fourier expansion is applied in the streamwise direction and in time and the solution is decomposed in Fourier modes along both z and t. The optimal unsteady spanwise-sinusoidal leading-edge excitation that provides the maximum energy growth for a given initial energy and frequency can thus be determined. Of interest will be that the optimal growth decreases with both.
Theory to Help the Use of Electromagnetic Flow Meters
Authors: Zhang Xiao-Zhang
Published: March 2009

Compared with other flow meters, the theory of electromagnetic flow meter is well developed. Until now, we are able to predict the three dimensional characteristics of this kind of flow meters with reasonable accuracy. This has given much help to the designers to improve the flow meters. On the other hand, the theory can offer a tool for the users of this kind of flow meters to judge the application situations, estimate the possible measurement error, etc. This paper introduces the recent work of the author on the theory of the electromagnetic flow meter. The basic physical conceptions and equations are given with a brief history review of the theory research. Several examples are given of using the theory to analyze the meters’ behavior in different application situations. They are: effect of the conducting pipe connections; errors caused by a pipe wall of different electromagnetic properties; gas-liquid flow and errors caused by a relative motion of the probe.
Investigation of the Effect of Cell Deposition and Declogging on Bioconvection in Porous Media
Authors: Kuznetsov A. V. , Jiang N.
Published: March 2009

The mechanisms of deposition and declogging are considered while formulating a new continuum model for bioconvection in a dilute suspension of swimming, gravitactic microorganisms in a porous medium. “Bioconvection” is the name given to pattern-forming convective motions set up in suspensions of swimming microorganisms. “Gravitaxis” means that microorganisms tend to swim against the gravitational force. The aim of this paper is to analyze the collective behavior and pattern formation in populations of swimming microorganisms. The decrease of permeability due to cell adsorption by the porous medium is considered and the influence this permeability decrease has on the development of bioconvection is studied. The existence and stability of a two-dimensional plume in a rectangular chamber with stress-free sidewalls is investigated. Governing equations include the Darcy law as well as the microorganism conservation equation. A conservative finite-difference scheme is utilized to solve these equations numerically. The analysis of the proposed model reveals that major factors that affect the development of bioconvection are the initial permeability of the porous medium and the rate of cell deposition. For small permeability, the resistance to the fluid flow is too large, and bioconvection does not develop. If the rate of cell deposition is too large, the number of suspended cells quickly becomes too small because of the capturing of cells by the porous medium. For this reason the critical density difference in the top fluid layer cannot be reached, and bioconvection does not develop.
A Combustion Study of Gas Turbines Using Multi-Species/Reacting Computational Fluid Dynamic
Authors: Armand Sasan , Chen Mei
Published: March 2009

A multi-species/reacting combustion study was performed. The focus of the study was to quantify the effects of variation in air extraction and power rates on flame/outlet temperatures of a General Electric (GE), Frame 5 gas turbine. The environmental contamination level due to generation of carbon monoxide was also reported. GE, Frame 5 gas turbine has been widely used around the world for power generation, and as mechanical drives. The combustion products were examined throughout a range of air extraction rates, upon which it was determined that the combustion liners were susceptible to damage at air extraction rates above 10%, and the environmental contamination level due to carbon monoxide was increased. Furthermore, the gas flow exiting the combustion liner became non-homogeneous (i.e. a pocket of relatively hot gas formed in the middle of the flow path), which would cause damage to the downstream components. In conclusion, the short-term monetary gains from using compressed air from a gas turbine do not justify the costs of down time for repairs and the replacement of expensive hot-gas-path components.
3D Direct Numerical Simulation of Air Bubbles in Water at High Reynolds Number
Authors: Koebe Mario , Bothe Dieter , Pruess Jan , Warnecke Hans-Joachim
Published: March 2009

This article presents direct numerical simulations of single air bubbles and bubble pairs in water (with log Mo = −10.6) with a highly parallelized code based on the Volume Of Fluid method (VOF). Systematical simulations of terminal velocity of single bubbles with a diameter ranging from 0.5–15 mm (ReB = 200–3750) show good agreement with experimental data from Clift et al. Bubbles with a diameter of 8 mm show strong realistic surface deformations. Initial white noise has been added to all simulations to create realistic starting conditions. Rise paths of the bubbles depend strongly on the boundary conditions and the wall distance. Small wall distances reduce the path radii of the bubbles leading to an increased wake shedding frequency. For bubble pairs with wobbling surfaces the phenomenon of shedding of vortices from the edges of the bubbles is observed.
Multiple Node Breakup of a Liquid Jet Into Drops in Another Immiscible Liquid
Authors: Homma Shunji , Koga Jiro , Matsumoto Shiro , Tryggvason Gre´tar
Published: March 2009

We investigate numerically the breakup of an axisymmetric jet into drops in liquid-liquid systems, specifically focus on multiple node breakup, where more than one node of the most unstable wave becomes one drop. The unsteady Navier-Stokes equations for incompressible Newtonian fluids are solved with a Front-Tracking / Finite Difference method. Various combinations of the non-dimensional numbers (Re = 80, 160, 320; We = 5, 8; Fr = 4, 8, 32, ∞) are examined for constant ratios of density (ρc, ρj = 1.25) and viscosity (µc, µj = 1). Capillary waves grow on the jet surface and the multiple node breakup is observed in all cases examined. A “shoulder” is observed on the jet right behind the bulb when the double-node breakup occurs. Unlike the breakup of a jet in air, vortical motions in the external fluid affect the breakup process.
Design of a Low-Turbulence Facility for Micro-Scale Aerodynamics
Authors: Martin Michael J. , Boyd Iain D. , Bernal Luis P.
Published: March 2009

A novel wind-tunnel facility has been designed for measurement of lift and drag on micromachined airfoils. Due to the structural and geometric constraints of the airfoils being tested, the wind tunnel has a 1-centimeter cross-section. This small size allows the use of a 100-1 contraction area, and extremely fine turbulence screens, creating an ultra-low turbulence facility. Preliminary velocity data obtained with a hot-wire probe indicate a successful design, with uniform flow, and turbulence intensities below 1%.
Characteristics of Single-Phase Flow in Microchannels
Authors: Chung Peter M.-Y. , Kawaji Masahiro , Kawahara Akimaro
Published: March 2009

Experiments were performed to study the flow behaviour of de-ionized water and nitrogen gas through round capillary rubes having an inner diameter of 100µm. At steady state, the single-phase pressure drop along the glass microchannel was measured and analysed. To compare with conventional flow theory, an evaluation was made of the friction factor constant for laminar flow and critical Reynolds number for the transition from laminar to turbulent flow. The liquid flow data were well predicted by the conventional friction factor equations for larger channels, and the critical Reynolds number was close to the traditional macro-scale value. For single-phase gas flow, the measured friction factors were found to agree with theory if compressibility effects are taken into account. The addition of compressibility yields a non-linear pressure distribution that arises from the density change of the gas in the channel. Unlike liquid flow in microchannels, the gas friction factor constant depends on the Reynolds number, which changes along the channel length. Moreover, compressibility caused the velocity to vary all along the length of the channel and prevented the flow from being fully-developed. The neglect of the slip-flow boundary condition and compressibility may account for the discrepancy between the experimental results of various researchers.
CFD/Monte Carlo Simulation of Collision-Dominated Gas-Particle Flows Over Bodies
Authors: Volkov Aleksei N. , Tsirkunov Yury M.
Published: March 2009

An efficient algorithm of numerical simulation of two-way coupled viscous flows of a dusty gas with collisions between particles is described. The flow of a carrier gas which is treated as a continuum is simulated by solving the modified Navier-Stokes equations using a CFD-method. The reverse effect of particles on a gas flow is modelled by the source terms entered into the momentum and energy equations. A dispersed phase is treated as a discrete set of particles which move in the carrier gas and can collide with each other. The particle drag force, the Magnus lift force, the damping torque and the heat exchange are taken into account in gas-particle interaction. Particles are assumed to collide inelastically and frictionally. A modified majorant frequency scheme of the Direct Simulation Monte Carlo (DSMC) method is proposed for computations of flow fields of a collisional “gas” of particles. The developed combined CFD / DSMC method is applied to the study of the supersonic gas-particle flow over a blunt body.
Cross-Wire Measurements in the Wake of an Airfoil at Low Reynolds Numbers With and Without Acoustic Excitation
Authors: Yarusevych Serhiy , Sullivan Pierre E. , Kawall John G.
Published: March 2009

The wake structure and vortex shedding characteristics of a NACA 0025 airfoil were studied experimentally. Wind tunnel experiments were carried out for three Reynolds numbers and three angles of attack by means of cross-wire measurements, spectral analysis and complementary surface flow visualization. Evidence of wake vortex shedding and flow separation was obtained for most of the cases examined, and dependence of these phenomena on Reynolds number and angle of attack was found. External acoustic excitation at a particular frequency was found to eliminate or reduce the separation region and decrease the airfoil wake. Moreover, the results show that the acoustic excitation has a significant effect on vortex shedding and can improve airfoil performance, i.e. produce an increase of the lift and/or decrease of the drag.
Numerical and Neural Study of the Turbulent Flow Around Sharp-Edged Bodies
Authors: Abdel Gawad Ahmed F.
Published: March 2009

The study is based on K-ε turbulence modeling using both structured and unstructured grids. The pressure distributions in the flow field and on the surfaces of the bodies are determined. Different parameters that affect the flow field such as Reynolds number, aspect ratio of the body, and flow direction are considered. Special concern is paid to the separations at the corners of the body and the circulations behind the body. The thermal behavior due to the flow field is also considered. Nusselt number on the heated surfaces of the body is examined. The thermal behavior of a given body is strongly dependent on its aerodynamic characteristics. Comparisons are made between the present results and the available experimental data. Artificial Neural Network (ANN) was used to predict the values of the drag coefficient. Many useful conclusions and suggestions were drawn from the study.
Comparison for Steady and Unsteady Simulations for High Pressure Turbine
Authors: Liamis N. , Sgarzi O. , El Ghazzani E. M.
Published: March 2009

For the new generation of advanced aero-engines, the turbine design is a key issue to most of the critical engine related factors, such as fuel consumption, component life, weight, duration and cost of the development program. For many years, an important effort has been devoted at Snecma Moteurs to the development, the validation and the industrialization of methods for the prediction of aerothermal phenomena in multi-stage turbines. The purpose of this contribution is to report on the recent advances of Snecma Moteurs CFD tools for aerodynamic turbine design and analysis. Three approaches, based on 3D Navier-Stokes calculations, each of them corresponding to a different level of complexity, are presented for the prediction of the aerodynamic behavior of high pressure turbines, showing the degree of accuracy and maturity that the turbine aerothermal methods of Snecma Moteurs, have now reached. Firstly, two types of steady stage simulation are considered. The first one uses the mixing plane method in order to transfer the flow information between adjacent blade rows, while the second one uses the average passage method proposed by Adamczyk [1]. Finally, the contribution of an unsteady stage simulation is investigated. Comparisons between computational results and experimental data for a high pressure turbine, tested in the frame of the European Research Programs IACA and TATEF are presented. An analysis is also performed, showing the advantages and the drawbacks of each approach for a realistic representation of the flow into a high pressure turbine stage.
Experimental and Numerical Study of the Coanda Effect Used to Reduce Self-Sustained Tones
Authors: Allery C. , Gue´rin S. , Hamdouni A. , Sakout A.
Published: March 2009

We present in this paper an experimental and numerical study about the Coanda effect which causes the sudden reattachment of a jet to an inclined plane. This phenomenon induces a large hysteresis loop, which can be used to reduce the noise produced by an airflow crossing two diaphragms in tandem inside a duct. The angle of the inclined wall with horizontal plane and the flow velocity are the two main parameters studied here. With the aim of doing optimal control, we propose to construct for this flow configuration a low-dimensional dynamical system with a basis issued from a Proper Orthogonal Decomposition.
Research on a Full Three-Dimenional Inverse Method for the Mixed-Flow Pump Runner
Authors: Fan Honggang , Chen Naixiang , Yang Lin , Xu Zhaohui , Qu Lunfu , Tang Shunping
Published: March 2009

In this paper, a full three-dimensional inverse method for the design of mixed-flow pump runner is described. The three-dimensional flow in the runner is decomposed into a tangential mean flow and a tangential periodic flow. The blades are represented by superposition of vortices and sources on the blade mean surface, and the blade mean surface is determined by the inverse method. In this method, the distribution of the circumferentially mean swirl VRθ on the meridional geometry of the runner is prescribed and the corresponding blade shape is computed iteratively. The new method is applied to the design of a mixed-flow pump runner and the result is satisfactory.