bluuebunny/crossref_metadata_2025 huggingface dataset:
Manufacturing Affinity
Authors: Page Joshua
Published: December 2007

Since at least the 1960s, scholars have argued that public ceremonies serve important practical functions for groups and social movements: bolstering internal cohesion; expressing messages about power, group identity, etc.; and fortifying intergroup ties. This article analyzes ethnographic data on the California Correctional Peace Officers Association (CCPOA), the very successful and powerful labor union that represents prison officers in California. Specifically, it examines two public gatherings that the CCPOA purportedly organizes on behalf of crime victims. During these events, the CCPOA manufactures affinity with its main allies, punitive crime victims' groups which the union helped create, and communicates to various audiences that prison officers and crime victims have a natural affinity and are natural allies. By demonstrating that the CCPOA uses these events to fabricate (make “real”) ties between itself and crime victims, this article contributes to our understanding of the practical uses of public ceremonies.
The Dignity of Job-Seeking Men
Authors: Purser Gretchen
Published: December 2007

Drawing on interviews and comparative ethnographic fieldwork in two day labor hiring sites (a street corner labor market and a “regulated” day labor worker center), this article examines the discourses through which Latino immigrant day laborers make sense of, and find dignity within, their ongoing quest for work. My findings reveal a clear pattern of “boundary work” along the center/street divide, wherein each group of day laborers asserts its dignity and masculinity by repudiating what they construe to be the feminine submission exemplified by the other group. I argue that gender both shapes and is shaped through the articulation of these moral boundaries and show how workers' struggle to attain dignity—in this case, via strategies of social differentiation and distinction—can act against the formation of a collective identity.
Philanthropic Strategies for School Reform
Authors: Ferris James M. , Hentschke Guilbert C. , Harmssen Hilary Joy
Published: December 2007

Although support for K-12 education has long been a priority for philanthropic organizations, foundations are increasingly choosing to play a leading role in fostering the development and implementation of new policies designed to reform K-12 education. This article is an effort to understand the strategies and tactics employed by foundations currently engaged in K-12 education policy. In-depth interviews conducted with senior staff members of 20 foundations identified as substantially engaged in education policy and school reform were conducted to examine three fundamental strategic choices: the foundation's decision to engage in education policy, including the specific policy domain within education; the foundation's choice on where to intervene in the policy process and at what level of government; and the foundation's tactics to leverage additional resources. Findings suggest that foundations consciously seek to engage in education policy as an integral ingredient of their philanthropic initiatives and are led by staff and board leadership in these decisions. Most foundation activities in this arena aim to create individual niches of activity within the school reform agenda based on the foundation's informed theory of change. As a group, however, foundation engagement in education policy is collectively cautious and ultimately incremental as foundations attempt to make change at the state and district level primarily through demonstration projects and funding research and development activities.
Increasing Academic Excellence and Enhancing Diversity Are Compatible Goals
Authors: Sternberg Robert Jeffrey
Published: December 2007

It is possible to simultaneously increase academic excellence and diversity. This article describes how the theory of successful intelligence can be used to accomplish both of these goals. The theory postulates that intelligence comprises creative skills in generating novel ideas, analytical skills in discerning whether they are good ideas, and practical skills in implementing the ideas and persuading others of their worth. The article summarizes the Rainbow Project, based on the theory of successful intelligence. The project involved creation and administration of tests of analytical, creative, and practical abilities to supplement the SAT. The tests substantially increase prediction of college success (as measured by first-year GPA) and decrease differences in scores among members of diverse ethnic groups.
The Impact of School Choice on Racial Segregation in Charter Schools
Authors: Garcia David R.
Published: December 2007

This study captures the impact of school choice decisions by comparing the racial composition of the district schools students exited to the charter schools they entered. Charter school catchment areas are operationalized using a statewide student-level database to track school attendance patterns of individual students over 4 years. Charter elementary school choosers enter charter schools that are more racially segregated than the district schools they exited, although on entrance into high school, choosers enter charter schools that are as racially segregated or more integrated than the district schools they exited. In addition, racial segregation patterns are the result of White flight and Black and Native American students self-segregating into charter schools that are more racially isolated than the district schools they exit.
A Unifying Perspective on the Quasi-steady Analysis of Magnetorheological Dampers
Authors: Hong Sung-Ryong , John Shaju , Wereley Norman M. , Choi Young-Tai , Choi Seung-Bok
Published: December 2007

A magnetorheological (MR) fluid, modeled as a Bingham plastic (BP) material, is characterized by a field dependent yield stress, and a (nearly constant) postyield plastic viscosity. Based on viscometric measurements, such a BP model is an idealization to physical MR behavior, albeit a useful one. A better approximation involves modifying both the preyield and postyield constitutive behavior as follows: (1) assume a high viscosity preyield behavior when the shear stress is less than the transition stress, and (2) assume a power law fluid (i.e., strain rate dependent viscosity) when the shear stress is greater than the transition stress. Assuming a power law fluid in postyield allows the model to account for shear thinning behavior exhibited by MR fluids at higher strain rates. Such an idealization for MR fluid constitutive behavior is called an viscous-power law model, or a Herschel—Bulkley (HB) model with preyield viscosity. This study develops a quasi-steady analysis for such a constitutive MR fluid behavior applied to an MR flow mode damper. Closed form solutions are developed for the fluid velocity, as well as key performance metrics, such as damping capacity and dynamic range (ratio of field-on to field-off force). For the given fluid properties and flow mode damper geometry, the fluid velocity profile and gradient, and the relationship of the damper force and piston velocity are analyzed. In addition, specializations to existing models, such as the HB, biviscous, and BP models, are shown to be easily captured by this model when physical constraints (idealizations) are placed on the rheological behavior of the MR fluid.
Two-way Antagonistic Shape Actuation Based on the One-way Shape Memory Effect
Authors: Sofla A.Y.N. , Elzey D.M. , Wadley H.N.G.
Published: December 2007

The stress created by the austenite transformation of mechanically constrained NiTi shape memory alloys (SMAs) significantly exceeds that required to deform (detwin) its low temperature martensitic phase. The one-way shape memory effect can therefore be used to create antagonistic, fully reversible flexural shape morphing structures by assembling opposing pairs of linear contractile SMA actuators. These structures possess two distinct inactive configurations, neither of which requires continuous power for shape retention making them potentially suitable for long-term applications. Here, the shape changes of a representative antagonistic flexural unit cell have been experimentally evaluated, and the effect of the pre-strain of near equiatomic NiTi alloys on the actuation strain has been analyzed and discussed. The predicted deformations are then successfully compared to the response of prototype actuators.
Biomimetic Nano-composite Actuators Based on Carbon Nanotubes and Ionic Polymers
Authors: Oh Il-Kwon , Jung Jin-Young
Published: December 2007

Based on carbon nanotubes and Nafion ionic polymers, a biomimetic nano-composite actuator has been developed by use of casting methods. The multi-walled carbon nanotubes (MWNT) with diameters of 3—5, 4—6 and 10—15 nm and length of 10—20 μm are used to enhance the basic performance of polymer actuators, with respect to electrical conductivity and mechanical stiffness. The carbon nanotubes are well dispersed in the Nafion matrix solution, using ultrasonic treatment and high speed homogenizer. The composite films are manufactured using a simple casting method. The electroless plating technique is used to make electrodes at the bottom and top surfaces of the composite film. SEM and TEM are used to characterize the surface and micro-structures of the composite actuators. In this study, novel biomimetic nano-composite actuators are developed and compared, with respect to bending actuation performance and electrical power consumption.
Cellulose Smart Material: Possibility and Challenges
Authors: Kim Jaehwan , Yun Sungryul , Lee Sun-Kon
Published: December 2007

This study presents an investigation of cellulose as a smart material that can be used for biomimetic sensor/actuator devices and microelectromechanical systems. This cellulose material is termed as electro-active paper (EAPap). First, the fabrication and recent improvement of EAPap materials are addressed. The actuation mechanism is explained by gathering all information on physical, chemical, electrical, and mechanical observations. In addition, the functional capability of sensor/actuator as a new smart material is discussed with experimental testimony. This smart material can be used for many applications, such as micro insect robots, micro flying objects, MEMS, biosensors, and flexible electrical displays. In summary, possibility of cellulose as smart material is addressed with challenges in this research.
Dynamic Characteristics of Three-axis Active Mount Featuring Piezoelectric Actuators
Authors: Choi Seung-Bok , Jung Woo Sohn  , Han Young-Min , Kim Jung-Wook
Published: December 2007

In this work, a new type of three-axis active mount using piezoelectric actuators is devised and its dynamic characteristics are investigated. Three piezoelectric actuators are installed on the rubber element with a certain inclined angle. After identifying dynamic properties of the rubber element and the piezoelectric actuator in frequency domain, the governing equation of the proposed active mount is derived. Using the governing equation associated with the identified system parameters, the generated force and moment of the active mount are evaluated in each axis by applying input voltage. In addition, a comparative work is undertaken between simulation and experiment. In order to verify the effectiveness of the proposed three-axis active mount, a vibrating system subjected to vertical, roll, and pitch motion is adopted and computer simulation is undertaken.
Prediction of Impact Forces on an Aircraft Composite Wing
Authors: Chan Yik Park  , Kim In-Gul
Published: December 2007

The capabilities for monitoring impact forces on an aircraft composite wing using impact response function (IRF) are examined. The IRF is derived based on the finite element method (FEM). Impact locations are identified by minimizing strain errors and force deviation errors. The reconstruction of impact forces are performed by computational inverse methods. The results of impact location identifications and impact force reconstructions are verified by numerical simulations using finite element analysis.
Three-Dimensional Reconstruction of a Cerebral Stent using Micro-CT for Computational Simulation
Authors: Ohta Makoto , Chuan He  , Nakayama Toshio , Takahashi Akira , Rüfenacht Daniel A.
Published: December 2007

The surface geometry of an intracranial stent (ICS) for a cerebral aneurysm is reconstructed by using micro-CT to import computational fluid simulations. The reconstructed stent with STL format is composed of 170,948 triangles with 0.04mm spatial resolutions. The boundary condition of the surface is clear without any reflection effects by X-ray introduced into the stainless steel stent. The computational simulations of blood flow with small implants, such as a stent or coil will be a designable way to control blood flow in/on a cerebral aneurysm and repair the disease. Micro-CT has a possibility of detecting the 3-D geometry of a small implant, such as ICS and may be useful to 3-D reconstruction and integration to computational simulation.
An Experimental Study on a SMA Driven Pressurized Hyper-redundant Manipulator
Authors: Lanteigne Eric , Jnifene Amor
Published: December 2007

This study describes the design and fabrication of a pressurized hyper-redundant manipulator driven by high strain shape memory alloy (SMA) actuators. Hyper-redundant devices are characterized by repeating independently controlled structures connected in series; their architecture is comparable to that of a snake or worm. The proposed design is composed of four identical modules; each providing three degrees of freedom from three symmetrically positioned actuators. The manipulator stiffness and actuator return-force are controlled by pressurized air, injected at the base of the manipulator. Tests on a single unit module have demonstrated that the design could achieve rotations of over 50° and displacements of over 40% at a frequency of 1/20 Hz.
Efficient Modeling of Ferroelectric Behavior for the Analysis of Piezoceramic Actuators
Authors: Hegewald Thomas , Kaltenbacher Barbara , Kaltenbacher Manfred , Lerch Reinhard
Published: December 2007

This work proposes a method of efficiently modeling the hysteresis of ferroelectric materials. Our approach includes the additive combination of a reversible and an irreversible portion of the polarization and strain, respectively. Whereas the reversible parts correspond to the common piezoelectric linear equations, the irreversible parts are modeled by hysteresis operators. These operators are based on Preisach and Jiles-Atherton hysteresis models which are well-established tools in ferromagnetic modeling. In contrast to micromechanical approaches, a Preisach or a Jiles-Atherton hysteresis operator can be efficiently numerically evaluated. A comparison of the resulting simulations to measured data concludes the article.
Magnetorheology of Single-walled Carbon Nanotube Dispersions in Mineral Oil
Authors: Zhengtao Yang  , Bahr Jeffrey , D'Souza Nandika Anne
Published: December 2007

The magnetorheological properties of single-walled carbon nanotube (SWNT)/mineral oil (MO) dispersions are studied using a parallel plate rheometer. Nanotubes of 1.24, 2.5, and 6.41 vol% are dispersed in mineral oil. Strain sweeps, frequency sweeps, magnetosweeps, and steady shear tests are conducted under various magnetic fields. Storage modulus G', loss modulus G '', complex viscosity η*, and dynamic yield stress τy increase with increase in magnetic field, which is partially attributed to the increasing degree of the alignment of nanotubes in a stronger magnetic field. The alignment of nanotubes is significantly restricted at a high nanotube concentration of 6.41 vol% due to the formation of a flocculated system. Increase in magnetic field increases the elastic properties of the dispersion, decreases the viscoelastic response, and delays the non-Newtonian behavior and transition from solid to liquid state. τy, G', and G'' of SWNT/mo dispersions scale with magnetic flux density by a power law similar to magnetorheological fluids (MRFs). The shear thinning behavior of SWNT/mo dispersions follows the Ostwald-de Waele or power law. SWNT/mo of 2.5 vol% shows the largest percent increase in G', G'', η* among the three concentrations of dispersions during magnetosweeps.
Nonlinear Semi-active Damping using Constant or Adaptive Voltage Sources: A Stability Analysis
Authors: Lallart Mickael , Badel Adrien , Guyomar Daniel
Published: December 2007

Semi-active vibration control techniques by nonlinear treatment have experienced strong development these last years, due to their effectiveness and advantages compared to passive and active approaches. In particular, the Synchronized Switch Damping (SSD) technique leads to very effective attenuation. This technique consists of a nonlinear processing of the piezovoltage that induces great enlargement of the electromechanical energy conversion. The SSD technique can be improved by switching on continuous voltage sources (SSDV), leading to an enlargement of the conversion energy cycle. This method is almost as effective as active techniques, but might generate instabilities. This article deals with these particular problems, focusing on CICO stability (Converging Input, Converging Output) and robustness. The study considers a theoretical and a technological point of view, confirmed by experimental results. The article also considers an enhanced SSDV, which uses matched continuous voltage sources, whereas the classical SSDV uses constant voltage sources. Simple monomodal and multimodal models of an electromechanical vibrating structure are proposed. Stability and robustness are discussed for the classical and enhanced SSDV techniques using the first harmonic method. It is shown both theoretically and experimentally that the enhanced SSDV is much more stable than the classical SSDV.
Design of a Novel Jetting Dispenser Featuring Piezostack and Linear Pump
Authors: Nguyen Q.H. , Choi M.K. , Yun B.Y. , Choi S.B.
Published: December 2007

This article presents a novel jetting dispenser featuring piezoelectric actuator incorporated with a linear positive displacement pump, to achieve high dispensing flow rate with small dot size. A multi-stack type of piezoelectric actuator is adopted and its output displacement is amplified via a hydraulic magnification mechanism. After describing the configuration and operating principle of the proposed dispensing system, static modeling is undertaken by analytical method to determine design parameters. The analytical result is then proven by finite element analysis. Subsequently, structural dynamic modeling and fluid dynamic modeling are analytically undertaken. In the dynamic modeling, fluid—solid interaction is considered to predict the dispensing dot size and average flow rate of the dispenser. Dispensing performances are investigated by changing the driving voltage of the piezostack actuator and velocity of the linear piston of the pump.
Experimental Investigation on the Aerodynamic Characteristics of a Bio-mimetic Flapping Wing with Macro-fiber Composites
Authors: Kim Dae-Kwan , Kim Hong-Il , Han Jae-Hung , Kwon Ki-Jung
Published: December 2007

This study describes the development of a bio-mimetic flapping wing and the aerodynamic characteristics of a flexible flapping wing. First, the flapping wing is designed to produce flapping, twisting, and camber motions by using a bio-mimetic design approach. A structural model for a macro-fiber composite (MFC) actuator is established, and structural analysis of a smart flapping wing with the actuator is performed to determine the wing configuration for maximum camber motion. The analysis model is verified with the experimental data of the smart flapping wing. Second, aerodynamic tests are performed for the smart flapping wing in a subsonic wind tunnel, and the aerodynamic forces are measured for various test conditions. Additionally, the effects of camber and chordwise wing flexibility on unsteady and quasi-steady aerodynamic characteristics are discussed. The experimental results demonstrate that the effect of the camber generated by the MFC produces sufficient aerodynamic benefit. It is further found that chordwise wing flexibility is an important parameter in terms of affecting aerodynamic performance, and that lift produced in a quasi-steady flow condition is mostly affected by the forward speed and effective angle of attack.
From the Gap to the Chasm
Authors: Kam Cindy D. , Zechmeister Elizabeth J. , Wilking Jennifer R.
Published: December 2007

This article focuses on gender and ethnic inequalities in political participation across non-Hispanic whites and Mexican Americans. Using a mainstream model of participation, the authors find that differences in the levels of resources, motivations, and opportunities effectively account for gender gaps within the two populations. However, this mainstream model leaves largely unexplained the chasm in participation across non-Hispanic whites and Mexican Americans. The authors incorporate socialization experiences specific to Mexican Americans to identify the roots of participatory inequality across these groups. Differences in linguistic, educational, and general assimilation account for participatory differences across Mexican Americans and non-Hispanic whites. Equalizing these factors closes the chasm in participation.
The Choreography of Gender
Authors: Yamanashi Leib Allison , Bulman Robert C.
Published: December 2007

The popularity of ballroom dance has ebbed and flowed over the years. In this article we argue that the attitude Americans have toward ballroom dance reflects society’s acceptance and rejection of different expressions of femininity and masculinity. Although ballroom dance is predicated on rigid gender roles, its popularity has increased in the United States over the past few years. We use in-depth interviews and participant observation to explore how modern ballroom dancers express their masculinity and femininity on and off the dance floor. We find that men and women construct complex gender identities that are both traditional and progressive. Some are creating gender identities incorporating traditional and nontraditional traits. Our interviewees reinforced this gender complexity and showed that no one is bound to one standard of masculinity or femininity. Rather, each person is free to choreograph his or her own gender identity.
The Performance-Enhancing Drug Game Reconsidered
Authors: Eber Nicolas
Published: December 2007

In this article, the author incorporates fair play norms into the analysis of the basic performance-enhancing drug game proposed in 2004 by Haugen (in the Journal of Sports Economics). In some cases, it leads to a modification in the very nature of the game, switching it from a prisoner's dilemma to a stag hunt game characterized by two pure-strategy equilibria: a risk-dominant doping equilibrium but also a payoff-dominant no-doping one. In such cases, the main problem for athletes becomes to coordinate their intentions and, hence, find a reliable coordinating device. The author suggests that some kind of preplay communication about doping and formal agreements through an antidoping charter may serve as such a device.
The Determinants of Soccer Player Substitutions
Authors: Del Corral Julio , Barros Carlos Pestana , Prieto-Rodríguez Juan
Published: December 2007

This paper analyzes the pattern of player substitutions during a soccer match using data from the Spanish First Division in the 2004—2005 season. We use an inverse Gaussian hazard model to analyze the first substitutions on each team taking place either at halftime or in the second half of the game. The results show that the most important factor explaining the timing of the first player substitutions on a team is the score as it stands prior to the substitution. Furthermore, defensive substitutions are made later in the match than offensive substitutions. We also found some evidence that home teams make more substitutions than visiting teams in the halftime interval.
Big-Time College Basketball and the Advertising Effect
Authors: Smith D. Randall
Published: December 2007

Proponents of big-time intercollegiate athletics highlight the public relations produced by successful programs and how this supports the educational mission. In the sports economics literature, this is called the "advertising effect,'' and several studies have found little or no effects for big-time basketball programs. Such conclusions may be premature because most analyses use subsets of all schools playing Division I basketball. The author analyzes how performance is related to academic quality in the first year class using all Division I schools during a 12-year panel. Neither the proportion of freshmen from the top 10th of their high school class, or with a grade point average of B or better, nor the number of entering National Merit Scholars are significantly related to measures of success. Freshman SAT scores are marginally related to one aspect of basketball performance. The conditions needed for a basketball advertising effect appear fleeting and difficult to accomplish.
Expansion of immunoglobulin autoreactive T-helper cells in multiple myeloma
Authors: Ostad Masih , Andersson Margareta , Gruber Astrid , Sundblad Anne
Published: December 2007

Activation and expansion of T helper (Th) cells followed by regulation of activation are essential to the generation of immune responses while limiting concomitant autoreactivity. In order to characterize T cells reactive towards myeloma-derived monoclonal immunoglobulin (mIg), an autologous coculture assay for single-cell analysis of mIg-responding cells was developed. When cultured with dendritic cells loaded with mIg, CD4+ Th cells from patients with progressing multiple myeloma (MM) showed a proliferative MHC class II–dependent response. CD8+ T-cell reactivity and Th1 activation were consistently low or absent, and Th2 and regulatory cytokines were expressed. The presence of such non-Th1 CD4+ T cells in peripheral blood was independent of treatment status, while the frequencies of responding cells varied between patients and reached the same order of magnitude as those measured for tetanus toxoid–specific Th memory cells. Furthermore, investigations of T-cell subpopulations indicated a possible regulatory role on the mIg responsiveness mediated by suppressive CD25highFOXP3+CD4+ T cells. It is proposed from the present results that a predominant in vivo activation of non-Th1 mIg-reactive CD4+ T cells constitute an Ig-dependent autoregulatory mechanism in human MM, with possible tumor growth supporting or permissive effects.
Activin-A: a novel dendritic cell–derived cytokine that potently attenuates CD40 ligand–specific cytokine and chemokine production
Authors: Robson Neil C. , Phillips David J. , McAlpine Tristan , Shin Amanda , Svobodova Suzanne , Toy Tracey , Pillay Vinochani , Kirkpatrick Naomi , Zanker Damien , Wilson Kathy , Helling Imke , Wei Heng , Chen Weisan , Cebon Jonathan , Maraskovsky Eugene
Published: December 2007

Activin-A is a transforming growth factor-β (TGF-β) superfamily member that plays a pivotal role in many developmental and reproductive processes. It is also involved in neuroprotection, apoptosis of tumor and some immune cells, wound healing, and cancer. Its role as an immune-regulating protein has not previously been described. Here we demonstrate for the first time that activin-A has potent autocrine effects on the capacity of human dendritic cells (DCs) to stimulate immune responses. Human monocyte-derived DCs (MoDCs) and the CD1c+ and CD123+ peripheral blood DC populations express both activin-A and the type I and II activin receptors. Furthermore, MoDCs and CD1c+ myeloid DCs rapidly secrete high levels of activin-A after exposure to bacteria, specific toll-like receptor (TLR) ligands, or CD40 ligand (CD40L). Blocking autocrine activin-A signaling in DCs using its antagonist, follistatin, enhanced DC cytokine (IL-6, IL-10, IL-12p70, and tumor necrosis factor-α [TNF-α]) and chemokine (IL-8, IP-10, RANTES, and MCP-1) production during CD40L stimulation, but not TLR-4 ligation. Moreover, antagonizing DC-derived activin-A resulted in significantly enhanced expansion of viral antigen-specific effector CD8+ T cells. These findings establish an immune-regulatory role for activin-A in DCs, highlighting the potential of antagonizing activin-A signaling in vivo to enhance vaccine immunogenicity.
Gas6 promotes inflammation by enhancing interactions between endothelial cells, platelets, and leukocytes
Authors: Tjwa Marc , Bellido-Martin Lola , Lin Yuan , Lutgens Esther , Plaisance Stéphane , Bono Françoise , Delesque-Touchard Nathalie , Hervé Caroline , Moura Rute , Billiau An D. , Aparicio Cristina , Levi Marcel , Daemen Mat , Dewerchin Mieke , Lupu Florea , Arnout Jef , Herbert Jean-Marc , Waer Mark , García de Frutos Pablo , Dahlbäck Björn , Carmeliet Peter , Hoylaerts Marc F. , Moons Lieve
Published: December 2007

The role of Gas6 in endothelial cell (EC) function remains incompletely characterized. Here we report that Gas6 amplifies EC activation in response to inflammatory stimuli in vitro. In vivo, Gas6 promotes and accelerates the sequestration of circulating platelets and leukocytes on activated endothelium as well as the formation and endothelial sequestration of circulating platelet-leukocyte conjugates. In addition, Gas6 promotes leukocyte extravasation, inflammation, and thrombosis in mouse models of inflammation (endotoxinemia, vasculitis, heart transplantation). Thus, Gas6 amplifies EC activation, thereby playing a key role in enhancing the interactions between ECs, platelets, and leukocytes during inflammation.
The MMSET protein is a histone methyltransferase with characteristics of a transcriptional corepressor
Authors: Marango Jotin , Shimoyama Manabu , Nishio Hitomi , Meyer Julia A. , Min Dong-Joon , Sirulnik Andres , Martinez-Martinez Yolanda , Chesi Marta , Bergsagel P. Leif , Zhou Ming-Ming , Waxman Samuel , Leibovitch Boris A. , Walsh Martin J. , Licht Jonathan D.
Published: December 2007

MMSET, identified by its fusion to the IgH locus in t(4;14)-associated multiple myeloma, possesses domains found within chromatin regulators, including the SET domain. MMSET protein is overexpressed and highly associated with chromatin in myeloma cell lines carrying t(4;14). MMSET possesses methyltransferase activity for core histone H3 lysine 4 and histone 4 lysine 20, whereas MMSET made in cells only modified H4. Segments of MMSET fused to the Gal4 DNA binding domain repressed transcription of a chromatin-embedded Gal4 reporter gene. MMSET-mediated repression was associated with increased H4K20 methylation gene and loss of histone acetylation. Consistent with this repressive activity, MMSET could form a complex with HDAC1 and HDAC2, mSin3a, and the histone demethylase LSD1, suggesting that it is a component of corepressor complexes. Furthermore, MMSET coexpression enhances HDAC1- and HDAC2-mediated repression in transcriptional reporter assays. Finally, shRNA-mediated knockdown of MMSET compromised viability of a myeloma cell line, suggesting a biologic role for the protein in malignant cell growth. Collectively, these data suggest that, by acting directly as a modifier of chromatin as well as through binding of other chromatin-modifying enzymes, MMSET influences gene expression and potentially acts as a pathogenic agent in multiple myeloma.
Genetic endothelial systems biology of sickle stroke risk
Authors: Chang Milbauer Liming , Wei Peng , Enenstein Judy , Jiang Aixiang , Hillery Cheryl A. , Scott J. Paul , Nelson Stephen C. , Bodempudi Vidya , Topper James N. , Yang Ruey-Bing , Hirsch Betsy , Pan Wei , Hebbel Robert P.
Published: December 2007

Genetic differences in endothelial biology could underlie development of phenotypic heterogeneity among persons afflicted with vascular diseases. We obtained blood outgrowth endothelial cells from 20 subjects with sickle cell anemia (age, 4-19 years) shown to be either at-risk (n = 11) or not-at-risk (n = 9) for ischemic stroke because of, respectively, having or not having occlusive disease at the circle of Willis. Gene expression profiling identified no significant single gene differences between the 2 groups, as expected. However, analysis of Biological Systems Scores, using gene sets that were predetermined to survey each of 9 biologic systems, showed that only changes in inflammation signaling are characteristic of the at-risk subjects, as supported by multiple statistical approaches. Correspondingly, subsequent biologic testing showed significantly exaggerated RelA activation on the part of blood outgrowth endothelial cells from the at-risk subjects in response to stimulation with interleukin-1β/tumor necrosis factorα. We conclude that the pathobiology of circle of Willis disease in the child with sickle cell anemia predominantly involves inflammation biology, which could reflect differences in genetically determined endothelial biology that account for differing host responses to inflammation.
Long-term maintenance of human hematopoietic stem/progenitor cells by expression of BMI1
Authors: Rizo Aleksandra , Dontje Bert , Vellenga Edo , de Haan Gerald , Schuringa Jan Jacob
Published: December 2007

The polycomb group (PcG) gene BMI1 has been identified as one of the key epigenetic regulators of cell fates during different stages of development in multiple murine tissues. In a clinically relevant model, we demonstrate that enforced expression of BMI1 in cord blood CD34+ cells results in long-term maintenance and self-renewal of human hematopoietic stem and progenitor cells. Long-term culture-initiating cell frequencies were increased upon stable expression of BMI1 and these cells engrafted more efficiently in NOD-SCID mice. Week 5 cobblestone area-forming cells (CAFCs) were replated to give rise to secondary CAFCs. Serial transplantation studies in NOD-SCID mice revealed that secondary engraftment was only achieved with cells overexpressing BMI1. Importantly, BMI1-transduced cells proliferated in stroma-free cytokine-dependent cultures for more than 20 weeks, while a stable population of approximately 1% to 5% of CD34+ cells was preserved that retained colony-forming capacity. Whereas control cells lost most of their NOD-SCID engraftment potential after 10 days of ex vivo culturing in absence of stroma, NOD-SCID multilineage engraftment was retained by overexpression of BMI1. Thus, our data indicate that self-renewal of human hematopoietic stem cells is enhanced by BMI1, and we classify BMI1 as an intrinsic regulator of human stem/progenitor cell self-renewal.
U1-snRNA–mediated rescue of mRNA processing in severe factor VII deficiency
Authors: Pinotti Mirko , Rizzotto Lara , Balestra Dario , Lewandowska Marzena Anna , Cavallari Nicola , Marchetti Giovanna , Bernardi Francesco , Pagani Franco
Published: December 2007

Small nuclear U1-RNAs (snRNAs), the spliceosome components selectively recognizing donor splice sites (5′ss), were engineered to restore correct mRNA processing in a cellular model of severe coagulation factor VII (FVII) deficiency, caused by the IVS7 9726 + 5g/a change. Three U1-snRNAs, complementary to the mutated 5′ss (U1 + 5a) or to neighboring sequences were expressed with FVII minigenes in a hepatoma cell line. The U1-snRNAs reduced from 80% to 40% the exon 7 skipping, thus increasing exon definition. The U1 + 5a construct also dramatically increased recognition of the correct 5′ss over the 37-bp downstream cryptic site preferentially activated by the mutation, thus inducing appreciable synthesis of normal transcripts (from barely detectable to 50%). This effect, which was dose-dependent, clearly demonstrated that impaired recognition by the U1-snRNA was the mechanism responsible for FVII deficiency. These findings suggest compensatory U1-snRNAs as therapeutic tools in coagulation factor deficiencies caused by mutations at 5′ss, a frequent cause of severe defects.
IL6/sIL6R complex contributes to emergency granulopoietic responses in G-CSF– and GM-CSF–deficient mice
Authors: Walker Francesca , Zhang Hui-Hua , Matthews Vance , Weinstock Janet , Nice Edouard C. , Ernst Matthias , Rose-John Stefan , Burgess Antony W.
Published: December 2007

Mice defective in both granulocyte colony-stimulating factor (G-CSF) and granulocyte-macrophage colony-stimulating factor (GM-CSF) have severely impaired neutrophil production and function, yet these mice respond to acute pathogen challenge with a significant neutrophil response. We have recently reported the development of an in vitro system to detect granulopoietic cytokines secreted from cells isolated from G-CSF, GM-CSF double knockout mice. The conditioned media produced by these cells after stimulation with lipopolysaccharide or Candida albicans supports the production and differentiation of granulocytes (ie, the conditioned media contains neutrophil promoting activity [NPA]). We now show that the NPA in the G-CSF−/−/GM-CSF−/− conditioned media requires interleukin-6 (IL6), is abolished by soluble gp130, and can be specifically immunodepleted by an anti-IL6R antibody. NPA effects on bone marrow cells are also mimicked by Hyper-IL6, and the soluble IL6R is present in NPA. These results show that the IL6/sIL6R complex is the major effector of NPA. NPA production by mice defective for both G-CSF and GM-CSF uncovers an alternative pathway to granulocyte production, which is activated after exposure to pathogens.
Conserved and species-specific alternative splicing in mammalian genomes
Authors: Nurtdinov Ramil N , Neverov Alexey D , Favorov Alexander V , Mironov Andrey A , Gelfand Mikhail S
Published: December 2007

Background

Alternative splicing has been shown to be one of the major evolutionary mechanisms for protein diversification and proteome expansion, since a considerable fraction of alternative splicing events appears to be species- or lineage-specific. However, most studies were restricted to the analysis of cassette exons in pairs of genomes and did not analyze functionality of the alternative variants.

Results

We analyzed conservation of human alternative splice sites and cassette exons in the mouse and dog genomes. Alternative exons, especially minor-isofom ones, were shown to be less conserved than constitutive exons. Frame-shifting alternatives in the protein-coding regions are less conserved than frame-preserving ones. Similarly, the conservation of alternative sites is highest for evenly used alternatives, and higher when the distance between the sites is divisible by three. The rate of alternative-exon and site loss in mouse is slightly higher than in dog, consistent with faster evolution of the former. The evolutionary dynamics of alternative sites was shown to be consistent with the model of random activation of cryptic sites.

Conclusion

Consistent with other studies, our results show that minor cassette exons are less conserved than major-alternative and constitutive exons. However, our study provides evidence that this is caused not only by exon birth, but also lineage-specific loss of alternative exons and sites, and it depends on exon functionality.
Checkpoint effects and telomere amplification during DNA re-replication in fission yeast
Authors: Mickle Katie L , Oliva Anna , Huberman Joel A , Leatherwood Janet
Published: December 2007

Background

Although much is known about molecular mechanisms that prevent re-initiation of DNA replication on newly replicated DNA during a single cell cycle, knowledge is sparse regarding the regions that are most susceptible to re-replication when those mechanisms are bypassed and regarding the extents to which checkpoint pathways modulate re-replication. We used microarrays to learn more about these issues in wild-type and checkpoint-mutant cells of the fission yeast, Schizosaccharomyces pombe.

Results

We found that over-expressing a non-phosphorylatable form of the replication-initiation protein, Cdc18 (known as Cdc6 in other eukaryotes), drove re-replication of DNA sequences genome-wide, rather than forcing high level amplification of just a few sequences. Moderate variations in extents of re-replication generated regions spanning hundreds of kilobases that were amplified (or not) ~2-fold more (or less) than average. However, these regions showed little correlation with replication origins used during S phase. The extents and locations of amplified regions in cells deleted for the checkpoint genes encoding Rad3 (ortholog of human ATR and budding yeast Mec1) and Cds1 (ortholog of human Chk2 and budding yeast Rad53) were similar to those in wild-type cells. Relatively minor but distinct effects, including increased re-replication of heterochromatic regions, were found specifically in cells lacking Rad3. These might be due to Cds1-independent roles for Rad3 in regulating re-replication and/or due to the fact that cells lacking Rad3 continued to divide during re-replication, unlike wild-type cells or cells lacking Cds1. In both wild-type and checkpoint-mutant cells, regions near telomeres were particularly susceptible to re-replication. Highly re-replicated telomere-proximal regions (50–100 kb) were, in each case, followed by some of the least re-replicated DNA in the genome.

Conclusion

The origins used, and the extent of replication fork progression, during re-replication are largely independent of the replication and DNA-damage checkpoint pathways mediated by Cds1 and Rad3. The fission yeast pattern of telomere-proximal amplification adjacent to a region of under-replication has also been seen in the distantly-related budding yeast, which suggests that subtelomeric sequences may be a promising place to look for DNA re-replication in other organisms.
Obesity and craniofacial variables in subjects with obstructive sleep apnea syndrome: comparisons of cephalometric values
Authors: Cuccia Antonino M , Campisi Giuseppina , Cannavale Rosangela , Colella Giuseppe
Published: December 2007

Background

The aim of this paper was to determine the most common craniofacial changes in patients suffering Obstructive Sleep Apnea Syndrome (OSAS) with regards to the degree of obesity. Accordingly, cephalometric data reported in the literature was searched and analyzed.

Methods

After a careful analysis of the literature from 1990 to 2006, 5 papers with similar procedural criteria were selected. Inclusion criteria were: recruitment of Caucasian patients with an apnea-hypopnea index (AHI) >10 as grouped in non-obese (Body Mass Index – [BMI] < 30)vs. obese (BMI ≥ 30).

Results

A low position of the hyoid bone was present in both groups. In non-obese patients, an increased value of the ANB angle and a reduced dimension of the cranial base (S-N) were found to be the most common finding, whereas major skeletal divergence (ANS-PNS ^Go-Me) was evident among obese patients. No strict association was found between OSAS and length of the soft palate.

Conclusion

In both non-obese and obese OSAS patients, skeletal changes were often evident; with special emphasis of intermaxillary divergence in obese patients. Unexpectedly, in obese OSAS patients, alterations of oropharyngeal soft tissue were not always present and did not prevail.
Ethnography Two Decades After Writing Culture: From the Experimental to the Baroque
Authors: Marcus George E
Published: December 2007

Since the 1980s, and the Writing Culture critique of ethnographic representation, the writing of ethnographic texts in anthropology has been distinguished by the perennial appearance of new works composed of tropes and stylistic strategies that reflect the diverse influences of the period of critique. These "messy" texts were, and are, valorized as experiments. This essay argues that as critique such ethnographies are not so much experimental as baroque, indicating perhaps a limit of the historic ethnographic form, and the need to push the spirit of experiment back toward the conditions of producing ethnography in fieldwork. This "refunctioning" of ethnography in its experimental spirit would recognize and address the present limit of the baroque to which the 1980s period of critique and after has led.
Between Yad Vashem and Mt. Herzl: Changing Inscriptions of Sacrifice on Jerusalem's "Mountain of Memory"
Authors: Feldman Jackie
Published: December 2007

Focusing on recent changes at a central Israeli site marking the Holocaust and the fallen, I demonstrate that memorial sites are palimpsests, with careers that reflect changing understandings of death and national sacrifice. In the early years of statehood, the site and the rituals performed there depicted Holocaust victims as morally inferior to Israeli independence fighters; recent monuments, paths and rituals, constructed during or after the second Intifada, grant Israeli soldiers legitimacy insofar as they are linked with innocent victims of the Shoah. Suggesting a comparison with post-9/11 Washington, DC, I show that commemorative paths carry two-way traffic between past and present. While memorial sites and rites may displace immanent fear of death to a heroic past, the distant past may also be recharged with the anxieties of the lived present, thus imbuing current others with the cosmological evil attached to the past enemy.
Profession and Faith: The National Guild of Catholic Psychiatrists, 1950-1968
Authors: Nussbaum Abraham
Published: December 2007

In the early 1950's, Roman Catholics in America were underrepresented as psychiatric patients and practitioners, and a group of lay Catholic psychiatrists organized a National Guild of Catholic Psychiatrists and published the Bulletin of the Guild of Catholic Psychiatrists as a first step towards establishing an institutional Catholic presence within American psychiatry. From 1952 to 1968, the members of the Guild taught Catholic clergy to adopt psychiatric methods both for the selection and training of their members, and for the pastoral counsel with which they succored the laity. The Guild successfully introduced psychiatry into the Catholic experience, but they failed to create a thriving subculture within American psychiatry; the Guild is an exemplary failure in the efforts of Roman Catholics in America to create distinctly Catholic institutions.
Tragical-Comical-Pastoral-Colonial: Economic Sovereignty, Globalization, and the Form of Tragicomedy
Authors: Lesser Zachary
Published: December 2007

I examine the politics of tragicomedy by focusing on its 1620s shift from pastoral to proto-colonial settings. This formal transformation reveals the genre's connection to economic debates over England's coin shortage and to Thomas Mun's abstract, global model of trade, removed from monarchical authority and naturalized in self-regulating "laws of commerce." Like Mun's model, tragicomedy requires us to imagine the ability of past actions and distant causes to ramify across time and space. Set on a barren, inaccessible island, Fletcher and Massinger's Sea Voyage isolates the nature of money and demonstrates the dangers of transgressing the natural law of commerce.
"Who Taught This Foreign Woman About the Ways and Lives of the Jews?": George Eliot and the Hebrew Renaissance
Authors: Dekel Mikhal
Published: December 2007

The essay centers on the Hebrew translation and the reception of George Eliot's Daniel Deronda among Hebrew readers of the late nineteenth century. It provides a historical account of the various translation stages and analyzes Deronda's importance as model citizen among aspiring nationalists. It also investigates Eliot's place, and the place of women in general, within the predominantly male Hebrew reading public.