bluuebunny/crossref_metadata_2025 huggingface dataset:
Identification of Phox2b-regulated genes by expression profiling of cranial motoneuron precursors
Authors: Pla Patrick , Hirsch Marie-Rose , Le Crom Stéphane , Reiprich Simone , Harley Vincent R , Goridis Christo
Published: June 2008

Background

Branchiomotor neurons comprise an important class of cranial motor neurons that innervate the branchial-arch-derived muscles of the face, jaw and neck. They arise in the ventralmost progenitor domain of the rhombencephalon characterized by expression of the homeodomain transcription factors Nkx2.2 and Phox2b. Phox2b in particular plays a key role in the specification of branchiomotor neurons. In its absence, generic neuronal differentiation is defective in the progenitor domain and no branchiomotor neurons are produced. Conversely, ectopic expression of Phox2b in spinal regions of the neural tube promotes cell cycle exit and neuronal differentiation and, at the same time, induces genes and an axonal phenotype characteristic for branchiomotor neurons. How Phox2b exerts its pleiotropic functions, both as a proneural gene and a neuronal subtype determinant, has remained unknown.

Results

To gain further insights into the genetic program downstream of Phox2b, we searched for novel Phox2b-regulated genes by cDNA microarray analysis of facial branchiomotor neuron precursors from heterozygous and homozygous Phox2b mutant embryos. We selected for functional studies the genes encoding the axonal growth promoter Gap43, the Wnt antagonist Sfrp1 and the transcriptional regulator Sox13, which were not previously suspected to play roles downstream of Phox2b and whose expression was affected by Phox2b misexpression in the spinal cord. While Gap43 did not produce an obvious phenotype when overexpressed in the neural tube, Sfrp1 induced the interneuron marker Lhx1,5 and Sox13 inhibited neuronal differentiation. We then tested whether Sfrp1 and Sox13, which are down-regulated by Phox2b in the facial neuron precursors, would antagonize some aspects of Phox2b activity. Co-expression of Sfrp1 prevented Phox2b from repressing Lhx1,5 and alleviated the commissural axonal phenotype. When expressed together with Sox13, Phox2b was still able to promote cell cycle exit and neuronal differentiation, but the cells failed to relocate to the mantle layer and to extinguish the neural stem cell marker Sox2.

Conclusion

Our results suggest novel roles for Sfrp1 and Sox13 in neuronal subtype specification and generic neuronal differentiation, respectively, and indicate that down-regulation of Sfrp1 and Sox13 are essential aspects of the genetic program controlled by Phox2b in cranial motoneurons.
Altered fractalkine cleavage potentially promotes local inflammation in NOD salivary gland
Authors: Wildenberg Manon E , van Helden-Meeuwsen Cornelia G , Drexhage Hemmo A , Versnel Marjan A
Published: June 2008

Introduction

In the nonobese diabetic (NOD) mouse model of Sjögren's syndrome, lymphocytic infiltration is preceded by an accumulation of dendritic cells in the submandibular glands (SMGs). NOD mice also exhibit an increased frequency of mature, fractalkine receptor (CX3C chemokine receptor [CX3CR]1) expressing monocytes, which are considered to be precursors for tissue dendritic cells. To unravel further the role played by fractalkine-CX3CR1 interactions in the salivary gland inflammation, we studied the expression of fractalkine in NOD SMGs.

Methods

We studied protein expression using Western blot analysis of whole tissue lysates. Protease activity was measured in salivary gland tissue lysates using fluorimetric substrates. Digestive capacity of enzymes was determined by in vitro incubation of recombinant enzyme and fractalkine, followed by protein staining and Western blot.

Results

Fractalkine was detected in salivary glands of both NOD and control mice at all ages. Western blot analysis showed fractalkine cleavage with increasing age, which was more pronounced in NOD mice. This cleavage resulted in a decrease in the 31 kDa form of the protein, and the generation of an approximately 19 kDa band. Furthermore, in NOD animals older than 15 weeks, we noted the presence of a unique approximately 17 kDa fragment. This cleavage was organ specific, because it did not occur in brain or pancreas. Increased gelatinase and α-secretase activity were detected in NOD SMG and contributed to cleavage of the 31 kDa protein. Because aberrant cleavage products may induce autoimmunity, we studied the presence of autoantibodies against fractalkine. Indeed, NOD mice exhibited significantly more antibodies against fractalkine than did control animals.

Conclusion

These data indicate that aberrant proteolytic activity in the NOD SMG results in increased fractalkine cleavage and generation of a unique fractalkine fragment. This specific cleavage may contribute to autoimmunity.
Single-stranded polyinosinic acid oligonucleotides trigger leukocyte production of proteins belonging to fibrinolytic and coagulation cascades
Authors: Zare Fariba , Magnusson Mattias , Möllers Linda Nilsson , Jin Tao , Tarkowski Andrej , Bokarewa Maria
Published: June 2008

The present study assessed the inductory effects of ds- and ssRNA on the leukocyte production of proteins belonging to fibrinolytic and coagulation cascades. Murine splenocytes were stimulated with dsRNA [polyinosinic:polycytidylic acid (polyIC)] and ssRNA sequences [polyinosinic acid (polyI), polycytidylic acid (polyC), and polyuridylic acid (polyU)]. The expression of plasminogen (Plg), tissue factor (TF), IL-6, and IFN-α was assessed. Intracellular tranduction mechanisms activated by oligonucleotides were evaluated using specific inhibitors of signaling pathways and genetically modified mice. polyIC efficiently and dose-dependently induced the expression of Plg, IL-6, and IFN-α, whereas TF was not induced by polyIC. polyI was unable to trigger IFN-α production, and it was efficiently inducing Plg and TF. IFN-αR and dsRNA-dependent protein kinase signaling were not required for the polyI-induced production of Plg or TF. Neither polyU nor polyC induced the expression of Plg or TF. Importantly, the presence of U- and C-nucleotide strands in the dsRNA significantly reduced expression of Plg and TF compared with polyI alone. Exposure of splenocytes to polyI activated the NF-κB pathway followed by the expression of TF and IL-6. In contrast, Plg production did not require NF-κB, was only partly down-regulated by p38 MAPK inhibitor, and was efficiently inhibited by insulin, indicating a different mechanism for its induction. ssRNA exerts its TF-generating properties through NF-κB activation in an IFN-α-independent manner. The expression of fibrinolytic versus coagulation proteins is regulated through distinctly different transduction pathways. As fibrinolytic and coagulation cascades are important components of inflammatory homeostatis, these findings might have importance for developement of new, targeted therapies.
Cholera toxin B subunit promotes the induction of regulatory T cells by preventing human dendritic cell maturation
Authors: D’Ambrosio Antonella , Colucci Manuela , Pugliese Orsola , Quintieri Francesca , Boirivant Monica
Published: June 2008

Cholera toxin B subunit (CTB) is an efficient mucosal carrier molecule for the generation of immune responses to linked antigens. There is also good evidence that CTB acts as an immunosuppressant, as it is able to down-modulate human monocyte/macrophage cell line activation and to suppress Th1-type responses. In the present study, we examined the possibility that recombinant CTB (rCTB) may affect human dendritic cell (DC) functions in response to LPS stimulation and may induce the generation of DC with the capacity to generate CD4+ regulatory T cells (Tregs). Our findings show that rCTB partially prevents the LPS-induced maturation process of monocyte-derived DC (MDDC) and decreases their IL-12 production with no relevant effect on IL-10 production. LPS-stimulated MDDC pretreated with rCTB are able to promote the induction of low proliferating T cells, which show an enhanced IL-10 production associated with a reduced IFN-γ production and the same high levels of TGF-β as the control. These T cells suppress proliferation of activated autologous T cells. Transwell experiments and blockade of IL-10R and TGF-β showed that the immunomodulatory effect is mediated by soluble factors. Thus, T cells induced by rCTB-conditioned MDDC acquire a regulatory phenotype and activity similar to those described for type 1 Tregs.
Ground-Motion Prediction Equations for the Average Horizontal Component of PGA, PGV, and 5%-Damped PSA at Spectral Periods between 0.01 s and 10.0 s
Authors: Boore David M. , Atkinson Gail M.
Published: June 2008

This paper contains ground-motion prediction equations (GMPEs) for average horizontal-component ground motions as a function of earthquake magnitude, distance from source to site, local average shear-wave velocity, and fault type. Our equations are for peak ground acceleration (PGA), peak ground velocity (PGV), and 5%-damped pseudo-absolute-acceleration spectra (PSA) at periods between 0.01 s and 10 s. They were derived by empirical regression of an extensive strong-motion database compiled by the “PEER NGA” (Pacific Earthquake Engineering Research Center's Next Generation Attenuation) project. For periods less than 1 s, the analysis used 1,574 records from 58 mainshocks in the distance range from 0 km to 400 km (the number of available data decreased as period increased). The primary predictor variables are moment magnitude ( M), closest horizontal distance to the surface projection of the fault plane ( RJB), and the time-averaged shear-wave velocity from the surface to 30 m ( VS30). The equations are applicable for M=5–8, RJB<200 km, and VS30=180–1300 m/s.
Correlation of Spectral Acceleration Values from NGA Ground Motion Models
Authors: Baker Jack W. , Jayaram Nirmal
Published: June 2008

Ground motion models (or “attenuation relationships”) describe the probability distribution of spectral acceleration at an individual period, given a set of predictor variables such as magnitude and distance, but they do not address the correlations between spectral acceleration values at multiple periods or orientations. Those correlations are needed for several calculations related to seismic hazard analysis and ground motion selection. Four NGA models and the NGA ground motion database are used here to measure these correlations, and predictive equations are fit to the results. The equations are valid for periods from 0.01 seconds to 10 seconds, versus similar previous equations that were valid only between 0.05 and 5 seconds and produced unreasonable results if extrapolated. Use of the new NGA ground motion database also facilitates a first study of correlations from intra- and inter-event residuals. Observed correlations are not sensitive to the choice of accompanying ground motion model, and intra-event, inter-event, and total residuals all exhibit similar correlation structure. A single equation is thus applicable for a variety of correlation predictions. A simple example illustrates the use of the proposed equations for one hazard analysis application.
Model for Basin Effects on Long-Period Response Spectra in Southern California
Authors: Day Steven M. , Graves Robert , Bielak Jacobo , Dreger Douglas , Larsen Shawn , Olsen Kim B. , Pitarka Arben , Ramirez-Guzman Leonardo
Published: June 2008

We propose a model for the effect of sedimentary basin depth on long-period response spectra. The model is based on the analysis of 3-D numerical simulations (finite element and finite difference) of long-period (2–10 s) ground motions for a suite of sixty scenario earthquakes (Mw 6.3 to Mw 7.1) within the Los Angeles basin region. We find depth to the 1.5 km/s S-wave velocity isosurface to be a suitable predictor variable, and also present alternative versions of the model based on depths to the 1.0 and 2.5 km/s isosurfaces. The resulting mean basin-depth effect is period dependent, and both smoother (as a function of period and depth) and higher in amplitude than predictions from local 1-D models. The main requirement for the use of the results in construction of attenuation relationships is determining the extent to which the basin effect, as defined and quantified in this study, is already accounted for implicitly in existing attenuation relationships, through (1) departures of the average “rock” site from our idealized reference model, and (2) correlation of basin depth with other predictor variables (such as V s30).
NGA Ground Motion Model for the Geometric Mean Horizontal Component of PGA, PGV, PGD and 5% Damped Linear Elastic Response Spectra for Periods Ranging from 0.01 to 10 s
Authors: Campbell Kenneth W. , Bozorgnia Yousef
Published: June 2008

We present a new empirical ground motion model for PGA, PGV, PGD and 5% damped linear elastic response spectra for periods ranging from 0.01–10 s. The model was developed as part of the PEER Next Generation Attenuation (NGA) project. We used a subset of the PEER NGA database for which we excluded recordings and earthquakes that were believed to be inappropriate for estimating free-field ground motions from shallow earthquake mainshocks in active tectonic regimes. We developed relations for both the median and standard deviation of the geometric mean horizontal component of ground motion that we consider to be valid for magnitudes ranging from 4.0 up to 7.5–8.5 (depending on fault mechanism) and distances ranging from 0–200 km. The model explicitly includes the effects of magnitude saturation, magnitude-dependent attenuation, style of faulting, rupture depth, hanging-wall geometry, linear and nonlinear site response, 3-D basin response, and inter-event and intra-event variability. Soil nonlinearity causes the intra-event standard deviation to depend on the amplitude of PGA on reference rock rather than on magnitude, which leads to a decrease in aleatory uncertainty at high levels of ground shaking for sites located on soil.
NGA Project Strong-Motion Database
Authors: Chiou Brian , Darragh Robert , Gregor Nick , Silva Walter
Published: June 2008

A key component of the NGA research project was the development of a strong-motion database with improved quality and content that could be used for ground-motion research as well as for engineering practice. Development of the NGA database was executed through the Lifelines program of the PEER Center with contributions from several research organizations and many individuals in the engineering and seismological communities. Currently, the data set consists of 3551 publicly available multi-component records from 173 shallow crustal earthquakes, ranging in magnitude from 4.2 to 7.9. Each acceleration time series has been corrected and filtered, and pseudo absolute spectral acceleration at multiple damping levels has been computed for each of the 3 components of the acceleration time series. The lowest limit of usable spectral frequency was determined based on the type of filter and the filter corner frequency. For NGA model development, the two horizontal acceleration components were further rotated to form the orientation-independent measure of horizontal ground motion (GMRotI50). In addition to the ground-motion parameters, a large and comprehensive list of metadata characterizing the recording conditions of each record was also developed. NGA data have been systematically checked and reviewed by experts and NGA developers.
An Overview of the NGA Project
Authors: Power Maurice , Chiou Brian , Abrahamson Norman , Bozorgnia Yousef , Shantz Thomas , Roblee Clifford
Published: June 2008

The “Next Generation of Ground-Motion Attenuation Models” (NGA) project is a multidisciplinary research program coordinated by the Lifelines Program of the Pacific Earthquake Engineering Research Center (PEER), in partnership with the U.S. Geological Survey and the Southern California Earthquake Center. The objective of the project is to develop new ground-motion prediction relations through a comprehensive and highly interactive research program. Five sets of ground-motion models were developed by teams working independently but interacting with one another throughout the development process. The development of ground-motion models was supported by other project components, which included (1) developing an updated and expanded PEER database of recorded ground motions, including supporting information on the strong-motion record processing, earthquake sources, travel path, and recording station site conditions; (2) conducting supporting research projects to provide guidance on the selected functional forms of the ground-motion models; and (3) conducting a program of interactions throughout the development process to provide input and reviews from both the scientific research and engineering user communities. An overview of the NGA project components, process, and products is presented in this paper.
An NGA Empirical Model for Estimating the Horizontal Spectral Values Generated by Shallow Crustal Earthquakes
Authors: Idriss I. M.
Published: June 2008

An empirical model for estimating the horizontal pseudo absolute spectral accelerations (PSA) generated by shallow crustal earthquakes is presented in this paper. The model was selected to be simple and the model parameters were estimated using the recordings gathered as part of the New Generation Attenuation (NGA) project. These parameters are presented for sites with an average shear wave velocity in the upper 30 m, VS30>900 m/s, and for sites with 450 m/s≤ VS30≤900 m/s. Site-specific dynamic response calculations are recommended for estimating spectral ordinates for sites with VS30≤180 m/s. Parameters for sites with 180 m/s< VS30<450 m/s are not included in this paper. The median values of peak horizontal ground acceleration (PGA) and PSA for short periods are on the order of 15% to 20% lower for strike slip events and 30% to 40% lower for reverse events than those calculated using pre-NGA relationships. The differences decrease significantly at longer periods. The minimum values of the standard error terms (for moment magnitude, M≥7.5) are about 15% to 30% larger and the maximum values of the standard error terms (for M≤5) are about 2% to 12% larger than the pre-NGA values.
Directivity in NGA Earthquake Ground Motions: Analysis Using Isochrone Theory
Authors: Spudich Paul , Chiou Brian S. J.
Published: June 2008

We present correction factors that may be applied to the ground motion prediction relations of Abrahamson and Silva, Boore and Atkinson, Campbell and Bozorgnia, and Chiou and Youngs (all in this volume) to model the azimuthally varying distribution of the GMRotI50 component of ground motion (commonly called “directivity”) around earthquakes. Our correction factors may be used for planar or nonplanar faults having any dip or slip rake (faulting mechanism). Our correction factors predict directivity-induced variations of spectral acceleration that are roughly half of the strike-slip variations predicted by Somerville et. al. (1997), and use of our factors reduces record-to-record sigma by about 2–20% at 5 sec or greater period.
Near Neutrality
Authors: Hughes Austin L.
Published: June 2008

The nearly neutral theory represents a development of Kimura's neutral theory of molecular evolution that makes testable predictions that go beyond a mere null model. Recent evidence has strongly supported several of these predictions, including the prediction that slightly deleterious variants will accumulate in a species that has undergone a severe bottleneck or in cases where recombination is reduced or absent. Because bottlenecks often occur in speciation and slightly deleterious mutations in coding regions will usually be nonsynonymous, we should expect that the ratio of nonsynonymous to synonymous fixed differences between species should often exceed the ratio of nonsynonymous to synonymous polymorphisms within species. Many data support this prediction, although they have often been wrongly interpreted as evidence for positive Darwinian selection. The use of conceptually flawed tests for positive selection has become widespread in recent years, seriously harming the quest for an understanding of genome evolution. When properly analyzed, many (probably most) claimed cases of positive selection will turn out to involve the fixation of slightly deleterious mutations by genetic drift in bottlenecked populations. Slightly deleterious variants are a transient feature of evolution in the long term, but they have substantially affected contemporary species, including our own.
Why Are Sex and Recombination So Common?
Authors: Hadany Lilach , Comeron Josep M.
Published: June 2008

The abundance of sex and recombination is still one of the most puzzling questions in the theory of evolution: Most models find that recombination can evolve, but only under a limited range of parameters. Here we review the major models and supporting evidence, concentrating on recent approaches where more realistic assumptions help explain the evolution of sex and recombination under a wider parameter range: finite populations, selection over long genomes, variation in recombination across the genome, and plasticity of sex and recombination. We discuss the similarities and differences between the evolution of sex and that of recombination.
Usefulness of Bioclimatic Models for Studying Climate Change and Invasive Species
Authors: Jeschke Jonathan M. , Strayer David L.
Published: June 2008

Bioclimatic models (also known as envelope models or, more broadly, ecological niche models or species distribution models) are used to predict geographic ranges of organisms as a function of climate. They are widely used to forecast range shifts of organisms due to climate change, predict the eventual ranges of invasive species, infer paleoclimate from data on species occurrences, and so forth. Several statistical techniques (including general linear models, general additive models, climate envelope models, classification and regression trees, and genetic algorithms) have been used in bioclimatic modeling. Recently developed techniques tend to perform better than older techniques, although it is unlikely that any single statistical approach will be optimal for all applications and species. Proponents of bioclimatic models have stressed their apparent predictive power, whereas opponents have identified the following unreasonable model assumptions: biotic interactions are unimportant in determining geographic ranges or are constant over space and time; the genetic and phenotypic composition of species is constant over space and time; and species are unlimited in their dispersal. In spite of these problematic assumptions, bioclimatic models often successfully fit present‐day ranges of species. Their ability to forecast the effects of climate change or the spread of invaders has rarely been tested adequately, however, and we urge researchers to tie the evaluation of bioclimatic models more closely to their intended uses.
Ecosystem Services Provided by Birds
Authors: Whelan Christopher J. , Wenny Daniel G. , Marquis Robert J.
Published: June 2008

Ecosystem services are natural processes that benefit humans. Birds contribute the four types of services recognized by the UN Millennium Ecosystem Assessment—provisioning, regulating, cultural, and supporting services. In this review, we concentrate primarily on supporting services, and to a lesser extent, provisioning and regulating services. As members of ecosystems, birds play many roles, including as predators, pollinators, scavengers, seed dispersers, seed predators, and ecosystem engineers. These ecosystem services fall into two subcategories: those that arise via behavior (like consumption of agricultural pests) and those that arise via bird products (like nests and guano). Characteristics of most birds make them quite special from the perspective of ecosystem services. Because most birds fly, they can respond to irruptive or pulsed resources in ways generally not possible for other vertebrates. Migratory species link ecosystem processes and fluxes that are separated by great distances and times. Although the economic value to humans contributed by most, if not all, of the supporting services has yet to be quantified, we believe they are important to humans. Our goals for this review are 1) to lay the groundwork on these services to facilitate future efforts to estimate their economic value, 2) to highlight gaps in our knowledge, and 3) to point to future directions for additional research.
Infectious Disease in Cervids of North America
Authors: Conner Mary Margaret , Ebinger Michael Ryan , Blanchong Julie Anne , Cross Paul Chafee
Published: June 2008

Over the past two decades there has been a steady increase in the study and management of wildlife diseases. This trend has been driven by the perception of an increase in emerging zoonotic diseases and the recognition that wildlife can be a critical factor for controlling infectious diseases in domestic animals. Cervids are of recent concern because, as a group, they present a number of unique challenges. Their close ecological and phylogenetic relationship to livestock species places them at risk for receiving infections from, and reinfecting livestock. In addition, cervids are an important resource; revenue from hunting and viewing contribute substantially to agency budgets and local economies. A comprehensive coverage of infectious diseases in cervids is well beyond the scope of this chapter. In North America alone there are a number of infectious diseases that can potentially impact cervid populations, but for most of these, management is not feasible or the diseases are only a potential or future concern. We focus this chapter on three diseases that are of major management concern and the center of most disease research for cervids in North America: bovine tuberculosis, chronic wasting disease, and brucellosis. We discuss the available data and recent advances in modeling and management of these diseases.
Collision Effects of Wind‐power Generators and Other Obstacles on Birds
Authors: Drewitt Allan L. , Langston Rowena H.W.
Published: June 2008

There is extensive literature on avian mortality due to collision with man‐made structures, including wind turbines, communication masts, tall buildings and windows, power lines, and fences. Many studies describe the consequences of bird‐strike rather than address the causes, and there is little data based on long‐term, standardized, and systematic assessments. Despite these limitations, it is apparent that bird‐strike is a significant cause of mortality. It is therefore important to understand the effects of this mortality on bird populations. The factors which determine avian collision risk are described, including location, structural attributes, such as height and the use of lighting, weather conditions, and bird morphology and behavior. The results of incidental and more systematic observations of bird‐strike due to a range of structures are presented and the implications of collision mortality for bird populations, particularly those of scarce and threatened species susceptible to collisions, are discussed. Existing measures for reducing collision mortality are described, both generally and specifically for each type of structure. It is concluded that, in some circumstances, collision mortality can adversely affect bird populations, and that greater effort is needed to derive accurate estimates of mortality levels locally, regionally, and nationally to better assess impacts on avian populations. Priority areas for future work are suggested, including further development of remote technology to monitor collisions, research into the causes of bird‐strike, and the design of new, effective mitigation measures.
Empty Words or Real Achievement? The Impact of Security Council Resolution 1325 on Women in Armed Conflicts
Authors: Binder Christina , Lukas Karin , Schweiger Romana
Published: June 2008

On October 31, 2000, the Security Council of the United Nations (UN) adopted Resolution 1325 as the first comprehensive document on strengthening the role of women and girls in conflict and postconflict situations. The article reviews the resolution's history and examines its potential for the advancement of women. The characteristic advantage of Resolution 1325 is its central idea of the empowerment of women in conflict and postconflict settings. However, have the objectives of the resolution been adequately endorsed at the international level? Have they been sufficiently implemented at the national level? Or have the commitments of Resolution 1325 remained empty words without further impact?

The article explores the case of Uganda to illustrate the effects of the resolution on women as peace-builders in a national context and discusses the advances in addressing gender issues in postconflict justice processes. It concludes that many of the commitments outlined in Resolution 1325 still remain to be implemented—at the level of the UN as well as in national contexts.
“I Believe in Human Rights, Not Women's Rights”: Women and the Human Rights State, 1969 1984
Authors: Clément Dominique
Published: June 2008

The following article challenges the assumption that human rights legislation promoted gender equality. International human rights treaties have established new standards for human rights, but it is at the local level at which the battle for human rights is won or lost. Historians of social movements are ideally placed to challenge the statist and legalistic assumptions dominating the current literature on human rights. Statists, in looking to the state to solve human rights violations, essentially advocate an increase in the power of states. Such an approach can be misleading if the obligation to deal with human rights issues lies with agencies lacking the power to solve the problems. In the case of British Columbia, Canada, human rights legislation proved a weak vehicle for advancing gender equality. This article is divided into two sections: the first part explores contrasting strategies for change within the women's movement, while the second part evaluates the success of the human rights state in light of feminists' objectives. As a locus of activism in Canada by the seventies—with the first gay-rights organizations and parades, the most radical feminist organizations, and the home of Greenpeace and dramatic student protests, as well as the most progressive human rights legislation in the country—British Columbia offers an ideal case study for examining the intersection of human rights discourse with feminist activism.
Gender, Colonialism, and Feminist Collaboration
Authors: Burton Antoinette , Allman Jean
Published: June 2008

This essay discusses the syllabus for “Gender and Colonialism,” a graduate seminar we have offered at the University of Illinois, both jointly and individually, over the course of the past six years. We recount its conception and execution as a feminist collaborative process by historians trained in different fields—Burton identifies as a British empire historian, Allman as an Africanist—as we have grappled with the limits and possibilities of the transnational as a historical concept and a feminist analytical tool in the context of thinking through what the combination of gender with colonialism might mean.
Strange Bedfellows: The Politics and Pathologies of Immigration Reform
Authors: Tichenor Daniel J.
Published: June 2008

The practical and ethical challenges posed by unauthorized immigration in the United States have a long history. In this article, which serves as the basis of discussion in this issue's Up for Debate section, Daniel Tichenor demonstrates how the immigration debate defies the usual liberal/conservative divide of U.S. politics and illustrates the different ways that distinct ideological camps define the problem of illegal immigration. He then shows how American immigration reform, because of the contentious politics it inspires, has been propelled over time by compromises among strange bedfellows. The legislative result for almost a century has been a series of Faustian bargains over porous borders and access to cheap, low-skilled labor. Equally important, the capacity and will of the national state to enforce its immigration laws have long been beleaguered by a tradition of inadequate resources, erratic leadership, and poor oversight. While the political spotlight usually trains on legislative wrangling over immigration reform and its legal outcomes, the devil often can be found in the details of enforcement. In addition to these significant historical patterns, however, are important new forces in the politics of immigration reform. These include the fresh political mobilization and growing influence of new immigrant groups as well as the shifting role of organized labor in immigration policy making.

In their generally sympathetic responses to Tichenor, economist Barry Chiswick stresses the costs of the modern-day welfare state as an additional consideration affecting political discussion in recent years, Nancy Foner expands the political dimension to encompass the diversity of state and local polities, while David Gutiérrez suggests that older, static ideas of “social membership” are being upended by the presence and uncowed activism of “noncitizens” in an era of global economic realignment.
Rollover analysis for the body section structure of a large bus using beam and non-linear spring elements
Authors: Park S-J , Yoo W-S
Published: June 2008

In the case of bus rollover, the body structure of a bus should be designed to ensure a survival space for passengers. This study focused on evaluating the rollover strength of a large bus at the initial stage of vehicle development. For this purpose, the section structure of a large bus was first modelled using simple beam elements, and the impact boundary conditions required by United Nations Economic Commission for Europe regulation 66 were applied. In order to validate the beam element model, the simulation results were compared with those of the shell element model and real experiments. Since the analysis error with the beam element model was mainly caused by the difference in strain energy at the connecting joint, the joint connection was modified with non-linear springs to account for the local buckling. With the improved beam model, the results were in good agreement with those of the shell element model and physically measured values, and the simulation time was much reduced.
Optimal power distribution strategy for series—parallel hybrid electric vehicles
Authors: Park J-Y , Park Y-K , Park J-H
Published: June 2008

The series—parallel hybrid electric vehicle (HEV), which employs a planetary gear set to combine one internal combustion engine and two electric motors, can take advantage of both series and parallel hybrid systems by controlling power flows. In this system, the control of power flows means adjusting not only the amount and direction of mechanical and electrical power but also the operating point of the engine. This study introduces a power distribution strategy to minimize the loss in power flow and to operate the engine at an efficient point. The strategy employs control maps to reduce the calculation load in deriving the most efficient operating point. Furthermore, an energy strategy to decide the optimal charging/discharging power of a battery is established using the results of the power distribution strategy. The control structure, in which the power distibution strategy and the energy strategy are merged, assures efficient driving of the HEV. A series of simulation and vehicle tests were performed to verify the effectiveness of the strategies and the results show a distinct improvement in fuel economy.
Fuzzy logic control of an electrohydraulic valve for auto-steering off-road vehicles
Authors: Rovira-Más F , Zhang Q
Published: June 2008

Most off-road vehicles employ fluid power to actuate their steering system. Although the actual force that turns the wheels is exerted by hydraulic cylinders, the critical element of a steering control system is the directional control valve. Auto-steering control is typically achieved by sending electrical signals to the valve solenoid drivers. A fuzzy logic controller was designed to create such steering signals. The fuzzy control algorithm was implemented in a hardware-in-the-loop electrohydraulic steering simulator. A set of 25 logic rules was defined to represent the four types of valve characteristic curve observed in different steering operations. The performance of the steering system depended on both the steering signal characteristics and the controller functionalities. The results obtained from this research provided some fundamental information for designing high-performance electrohydraulic steering controllers for autonomous off-road vehicles.
Modelling and injection rate estimation of common-rail injectors for direct-injection diesel engines
Authors: Chung N-H , Oh B-G , Sunwoo M-H
Published: June 2008

Diesel engines have evolved in order to meet stringent emission standards and to satisfy consumer demand for better fuel efficiency and increased power. The common-rail injection system was introduced in order to satisfy stringent emission standards, low fuel consumption, and low noise in recent years. The performance of a fuel injection system is strongly influenced by the injector characteristics. In this study, non-linear mathematical models are proposed for solenoid-operated and piezo-actuated injectors for control applications. Based on these models, the injection rate, which is one of the most important factors for the injection characteristics, is estimated using a sliding-mode observer. The simulation results and the experimental data show that the proposed sliding-mode observers can effectively estimate the injection timing and the injection rate for both types of common-rail injector.
Isotope Effect on Spin-crossover Transition in a New Two-dimensional Coordination Polymer [FeII(C5H5N)2][AuI(CN)2]2, [FeII(C5D5N)2][AuI(CN)2]2, and [FeII(C5H515N)2][AuI(CN)2]2
Authors: Kosone Takashi , Kachi-Terajima Chihiro , Kanadani Chikahide , Saito Toshiaki , Kitazawa Takafumi
Published: June 2008

A new Hofmann-like heterometal FeIIAuI two-dimensional (2D) spin-crossover compound, {[FeII(pyridine)2][AuI(CN)2]2}n (1) and its isotope-substituted analogues {[FeII(pyridine-D5)2][AuI(CN)2]2}n (2) and {[FeII(pyridine-15N)2][AuI(CN)2]2}n (3) have been synthesized in a simple synthetic method and characterized crystallographically and magnetically. Complex 1 consists of an octahedral FeII ion coordinated with the pyridine ligands and a mononuclear [AuI(CN)2]− unit with a linear coordination geometry, which combine to form an infinite 2D structure. The spin transitions observed for 1 and 3 are accompanied by drastic and reversible change of color from colorless to purple. In complexes 1 and 3, about 10 and 3.5% high-spin states are changed to low-spin states at 75 K. However, HS states in 2 are slightly more stable than those in 3.
Theoretical Study of Hydrogen Bonding Interaction of 1:1 Dimer of HNO with HArF
Authors: Liu Ying , Liu Wen-qing , Li Hai-yang , Yang Yong , Cheng Shuang
Published: June 2008

The hydrogen bonding interaction of 1:1 dimer formed between HNO and HArF molecule has been completely investigated in the present study using Second-order Moller-Plesset Perturbation (MP2) method in conjunction with 6-311+G**, 6-311++G** and 6-311++G(2d,2p) basis sets. The standard and CP-corrected calculations have been employed to determine the equilibrium structures, the vibrational frequencies and interaction energies. The interaction energies of the dimers were also calculated at G2MP2 level. Two stable structures are found as the minima. Dimer I(HF)is a five-membered cyclic hydrogen bonded structure and is more stable than the Dimer II(HO). The blue-shifted N-HF hydrogen bond is confirmed with standard and CP-corrected calculations by the MP2 and DFT methods in conjunction with different basis sets. The results obtained at MP2 in conjunction with different basis sets show there is a red-shifted hydrogen bond (Ar-HO) in the Dimer II(HO). The topological and electronic properties, the origin of red- and blue-shifted hydrogen bonds were investigated at MP2/6-311++G(2d,2p) with CP corrected calculations. From the NBO analysis, the reasonable explanations for the red- and blue-shifted hydrogen bonds were proposed.
Relationship Between Photocatalytic Activity and Structure of TiO2 Thin Film
Authors: Zhang Wen-zhen , Zhang Tao , Yin Wen , Cao Geng-yu
Published: June 2008

TiO2 thin films with different crystalline structures were prepared by the CVD method. The relationship between photocatalytic activity of a TiO2 thin film and its crystalline type was investigated. These films were characterized by XRD and AFM. Their photocatalytic properties were tested by the degradation of NO2-. The results showed that the crystalline structures of TiO2 thin films are primary anatase and/or rutile when the preparation temperatures were less than 573 K and higher than 773 K respectively. When the preparation temperature was around 623 K, the structures of TiO2 thin films were mixed crystalline structure, which showed the highest catalytic activity. When the ratio of rutile to anatase in TiO2 thin films fell between 0.5 and 0.7, the highest catalytic activity for the degradation of NO2- was found.
3D-QSAR of Benzothiazole Derivatives as Potent Anticancer Agents
Authors: Chen Jin-can , Shen Yong , Qian Li , Chen Lan-mei , Zheng Kang-cheng
Published: June 2008

Comparative molecular field analysis (CoMFA) method was applied to study three-dimensional quantitative structure activity relationship (3D-QSAR) of a series of benzothiazole derivatives as potent anticancer agents. The CoMFA model of cross-validation and the partial-least-square (PLS) model of non cross-validation have been well established. The best CoMFA model gives a good cross-validation coefficient of 0.642 and a conventional correlation coefficient of 0.976. Moreover, the estimated standard error is 0.161 and the statistical square deviation ratio F(3,20) is 111.4. The statistical parameters of the best CoMFA model show this model is reasonable and has predictive ability. The CoMFA results suggest that an electron-withdrawing group or atom (e.g. F atom) linking to the first atom (C19) of substituent R can increase the positive charges of C19 and its -site atoms, which lie in the blue-colored regions in the electrostatic field contour map of CoMFA, and thus can improve the activity of the compound. Meanwhile, selecting an R with an appropriate volume is also advantageous for improving the activity.
Bond Orbital-Connection Matrix Method to Predict Refractive Indices of Alkanes
Authors: Cao Chen-zhong , Gao Shuo
Published: June 2008

Based on the comprehension of the specific structural features affecting the refractive indices of the compounds, two descriptors X1CC and X1CH extracted from the bond orbital-connection matrix (BOCM) method were employed to develop a QSPR model for predicting the refractive indices of alkanes, chloroalkanes and bromoalkanes. The obtained results confirmed the usefulness of the BOCM method. X1CC and X1CH reflect the ability of the electronic cloud of the alkanes to be polarized; such ability is correlated with the refractive indices of substances. Therefore, the physical meaning of the obtained model can be rationally interpreted from the physical point of view. The present descriptors obtained by the BOCM method have the merit of topological indices (i.e. facility and rapid calculation of the descriptors) and the advantage of quantum descriptors (i.e. explicitly physical meaning of the parameters), which lead to an expectation of wide use in QSAR studies.
Existence of Bound-Rubber in Magnetorheological Elastomers and Its Influence on Material Properties
Authors: Zhang Xian-zhou , Gong Xing-long , Zhang Pei-qiang , Li Wei-hua
Published: June 2008

In efforts to develop a new fabrication method for improvement of the MREs' performance, the bound-rubber phenomenon was observed in MREs. Further experiments indicate the existance of bound-rubber, and it influences the MRE performance as well as the particle size. Both theoretical analysis and experimental results indicated that MRE performance can be improved by enhancing the ratio of particle radius to bound-rubber thickness.
Structures and Properties of Supported Polyimide/SnO2 Hybrid Membranes
Authors: Wang Mao-gong , Zhong Shun-he
Published: June 2008

A series of polyimide/SnO2 hybrid membranes supported on TiO2/kieselguhr-mullite were prepared from polyimide with a large amount of carboxyl and SnO2 sol via a sol-gel process. The SnO2 phase chemically linked with the polyimide through the pendant carboxyl along the polyimide. The hybrid membranes were highly homogeneous, and when the SnO2 contents reached 15wt% the SnO2 phase was observed as particles with a diameter of 5 nm dispersed in the hybrid membranes . The cross-linking between the SnO2 phase and polyimide effectively enhanced the glass temperature of the hybrid films. With the increasing of the SnO2 contents, the pore sizes of the membranes decreased, and their pore sizes were mainly focused on 3.8, 3.1, 2.8 and 2.4 nm. The hybrid membranes showed higher permeability for H2, CO2, CO and H2O when compared to the pure polyimide. The separation factors of the polyimide/SnO2 hybrid membranes with 15wt% SnO2 content for H2/N2, CO2/N2, CO/N2 and H2O/N2 were 54.1, 30.2, 35.9 and 40.1, respectively.
Convenient Approach to -Fe2O3 Nanoparticles: Magnetic and Electrochemical Properties
Authors: Li Bei-bei , Ji Ming-rong , Ni Xiao-min , Zhou Fu , Zhang Dong-en , Cheng Jing
Published: June 2008

A convenient approach is reported for the synthesis of spherical maghemite (-Fe2O3) nanoparticles. The process was realized by the controlled oxidation of Fe3O4 precursor, which originated from a facile partial-reduction co-precipitation process. The starting material of hydrosulfurous sodium (Na2S2O4), which can allow reaction to proceed without any deoxygenated protection, was proven to be important in the formation of the precursor. A series of techniques, including X-ray diffraction, transmission electron microscopy and a vibrating sample magnetometer were used to characterize the product. The resultant -Fe2O3 nanoparticles exhibited ferromagnetism at 300 K and the values of saturation magnetization and coercivity were 70 emu/g and 164 Oe, respectively. The electrochemical properties of lithium ions intercalation into -Fe2O3 nanoparticles were tested in Teflon cells. A specific capacity of 933 mAh/g was delivered at a current density of 0.2 mA/cm2 (voltage range 3.0-0.3 V vs. Li), corresponding to the reaction of 5.7 Li+ per Fe2O3. A possible mechanism of the reaction of lithium with maghemite spinel was discussed.
Film Reviews
Authors: Prout Ryan , Murray Jonathan
Published: June 2008

The Lost World of Tibet (2008) UK Director Emma Hindley Producer Emma Hindley Cinematography Johann Perry With Dan Cruikshank, the Dalai Lama. Runtime 90 minutes Preview Screening 26 February 2008 at the British Film Institute First
UK Broadcast 3 March 2008

There Will Be Blood (2007) USA Producers Paul Thomas Anderson, Daniel Lupi and JoAnne Sellar Director Paul Thomas Anderson Screenplay Paul Thomas Anderson Based on the novel Oil! by Upton Sinclair Cinematography Robert
Elswit Production Design Jack Fisk Costumes Mark Bridges Editor Dylan Tichenor Music Jonny Greenwood With Daniel Day-Lewis (Daniel Plainview), Paul Dano (Paul Sunday/Eli Sunday), Dillon Freasier (Young H.W. Plainview), Ciarn Hinds (Fletcher Hamilton), Russell
Harvard (Adult H.W. Plainview) Colour Runtime 158 minutes A Paramount Vantage release