bluuebunny/crossref_metadata_2025 huggingface dataset:
Applying the Newton—Raphson method in order to solve the Riccati algebraic equations in dynamic structural controlled models
Authors: Barbosa FS , Castro ES
Published: November 2010

This paper presents a solution for the Riccati algebraic equations using the Newton—Raphson method, resulting in a very precise algorithm that may be applied to dynamic control system models. This solution is a generalization of the Newton—Raphson-based algorithm originally developed to solve the Riccati equations in modal controlled models. The numerical implementation of this technique and an application are presented showing its accuracy. Comparison with a classical algorithm and an intrinsic Matlab© function shows the competitive performance of the proposed technique.
Vibration suppression of the rotor system using both a ball balancer and axial control of the repulsive magnetic bearing
Authors: Inoue Tsuyoshi , Niimi Hideaki , Ishida Yukio
Published: November 2010

In this paper we describe a strategy to eliminate the disadvantages of both a ball balancer and a repulsive magnetic bearing through the simultaneous application of both to a rotor system. The resultant force of the magnetic synchronous force caused by the repulsive magnetic bearing and the unbalance force is cancelled by the ball balancer, and the vibration during the passage through the critical speed caused by the ball balancer is also reduced by the axial control of the repulsive magnetic bearing. As a result, both the vibration suppression during the passage through the critical speed and the vibration reduction to zero at the rotational speed range above the critical speed are achieved simultaneously. The vibration suppression effect of the proposed method is also validated experimentally.
Vibration analysis of single lap adhesive joint: Experimental and analytical investigation
Authors: Ingole Sanjay B , Chatterjee Animesh
Published: November 2010

An analytical model to study the coupled transverse and longitudinal vibrations of a single lap adhesive joint is described in this paper, which includes partial differential form of the motion equations. A joint consists of two identical adherents of mild steel that are lap jointed over a certain length by a viscoelastic material, epoxy resin (araldite). Adherents are modeled as Euler-Bernoulli free-free beam. Both transverse and axial deformation of adherents and longitudinal shear and transverse peel stresses at the adhesive joint interface are considered in deriving the equations of motion. The numerical solutions of the governing equations for free vibrations yield the system’s natural frequency and mode shapes. Experimentation was carried out on both monolithic and adhesively jointed beams to observe the effect of the joint; natural frequencies of the system were measured experimentally and compared with those obtained theoretically. The fundamental frequency of a free-free jointed beam was more sensitive to joint overlap ratio. However natural frequency depended on the accelerometer location in the system, which was attributed to its mass contribution to the overall system mass. Theoretical frequency response function is generated for a beam with and without accelerometer mass to show the mass loading effect of the transducer (accelerometer).
A new hydraulic engine mount design without the peak frequency
Authors: Tikani R. , Vahdati N. , Ziaei-Rad S. , Esfahanian M.
Published: November 2010

Hydraulic engine mounts are generally applied to the aerospace and automotive applications for the purpose of cabin noise and vibration reduction. By careful selection of mount design parameters, at a certain frequency called the notch frequency, the dynamic stiffness will be smaller than the static stiffness. Following the notch frequency there will be a frequency, called the peak frequency, where the dynamic stiffness is much higher than the static stiffness. Increase in the dynamic stiffness above the static stiffness is not desirable because of the increase in transmitted force to the airframe or the chassis. Here in this paper, a new hydraulic engine mount design is proposed that uses two working fluids. This new design has two notch frequencies and two peak frequencies. Under special conditions, the peak frequency can be eliminated. As a result, one can obtain a hydraulic engine mount design with only one notch frequency but no peak frequency, by using a controllable fluid or a high viscosity fluid as one of the working fluids. The new hydraulic engine mount design, its mathematical model, and some discussions on the simulation results are presented.
Active stabilization of rotors with circulating forces due to spinning dissipation
Authors: Mukherjee A. , Sengupta S.
Published: November 2010

Destabilizing effects due to rotating dampers in gyrating or spinning systems govern their dynamic behavior very prominently. Tippe-tops and gyro-pendulums exhibit their seemingly counter intuitive behavior due to such dissipations. Rotors at speeds higher than certain threshold values become unstable due to rotating damping forces generated by dissipation in rotor material, couplings or due to friction in splines and tool tips. There are several techniques by which one may stabilize such rotors. Although the current methods in practice are quite effective for large or medium size rotors but these may not be suitable for small, mini or micro rotor systems. This paper proposes a class of alternative techniques to stabilize rotors any size through implementation of strategies developed here, however the selection of actuating mechanism would depend on the size of the rotor. In this paper the size of the rotor that may be actuated by piezo-electrical type actuators are considered. Thus may be called small size rotors. The rotor when it is not spinning is like two simple pendulums in two orthogonal planes (however when this rotor spins the cross coupling of motion between two planes takes place).
Controllability of regular systems and defective systems with repeated eigenvalues
Authors: Guofeng Yao  , Xuefei Gao
Published: November 2010

Controllability plays a key role in the vibration control of a structure, which can keep structural stability. In order to get practical conditions of structural controllability, two necessary conditions of controllability of a repeated eigenvalues system (regular and defective system) and their proofs are given. At the same time two sufficient conditions and their proofs are also presented. Finally we give a method of selecting control force distribution matrix B and some numerical examples.
Modal models for vibro-acoustic response analysis of fluid-loaded plates
Authors: Sheng Li
Published: November 2010

Modal models are developed for vibro-acoustic response computation of fluid-structure interaction problems on the basis of modal frequencies and modal damping ratios. The uncoupled equations are built using in vacuo mode shapes and fluid-loaded undamped real mode shapes and are solved for the coupled response of the fluid-loaded structures. Conventional modal analysis techniques are used to obtain the response of the coupled fluid-structure systems from a reduced-order modal model. The accuracy and efficiency of the technique is demonstrated with examples of computing the vibro-acoustic response of a baffled thin plate and a baffled thick stiffened plate. The comparisons in terms of mean-square normal velocity and sound power between the present models and the conventional coupling method show a good agreement. The present modal models for computing the vibro-acoustic response of the fluid-loaded structures have the advantages of constructing a model from modal parameters that could be obtained from either numerical computation or experimental measurement; a small dimension of using only a very small number of modes; and of being applicable to conventional modal analysis techniques. These features may make the present technique a powerful tool for dynamics and the control of fluid-loaded structures.
Green Tea Extract-Induced Lethal Toxicity in Fasted but Not in Nonfasted Dogs
Authors: Wu Kuei-Meng , Yao Jiaqin , Boring Daniel
Published: November 2010

Recent chronic toxicity studies performed on green tea extracts in fasted dogs have revealed some unique dose-limiting lethal liver, gastrointestinal, and renal toxicities. Key findings included necrosis of hepatic cells, gastrointestinal epithelia and renal tubules, atrophy of reproductive organs, atrophy and necrosis of hematopoietic tissues, and associated hematological changes. The polyphenol cachetins (a mixture of primarily epigallocatechin gallate [≥55%]; plus up to 10% each of epigallocatechin, epicatechin, and epigallocatechin gallate) appeared to be the causative agents for the observed toxicities because they are the active ingredients of green tea extract studied. Conduct of the study in nonfasted dogs under the same testing conditions and dose levels showed unremarkable results. Assuming both studies were valid, at the identified no observed adverse effect levels (NOAEL) of each study, systemic exposures (based on area under the curve [AUC]) were actually lower in fasted than nonfasted dogs, suggesting that fasting may have rendered the target organ systems potentially more vulnerable to the effects of green tea extract. The toxicity mechanisms that produced lethality are not known, but the results are scientifically intriguing. Because tea drinking has become more popular in the United States and abroad, the mode of action and site of action of green tea extract-induced lethal toxicities during fasting and the role of other phytochemical components of Folia Camellia sinensis (including nonpolyphenol fractions, which are often consumed when whole-leaf products are presented) warrant further investigation.
A Strength-Based Approach to Parent Education for Children With Autism
Authors: Steiner Amanda Mossman
Published: November 2010

Despite the ubiquitous nature of parent education in autism treatment, relatively few studies directly address how parent education should be conducted. Given that the literature on parental well-being suggests that treatments that facilitate positive parental adaptation to their child’s disability may be beneficial, this study examined the impact of a strength-based approach to parent education. An alternating treatments design was used to compare the effects of therapist statements that highlighted the child’s deficits versus those that emphasized strengths. These two approaches were evaluated on the following measures: parent affect, parent statements regarding child behavior, and the quality of parent—child interactions. Results indicate that parents displayed improved affect, made more positive statements about their child, and also exhibited more physical affection toward their child during the strength-based approach. Findings have implications for autism programming, parental coping, and parent—child relationships.
Traversing sites of confinement
Authors: Jefferson Andrew M.
Published: November 2010

In February 2006 a group of over 50 former fighters were released from Freetown’s central prison after over six years’ incarceration. This article traces the ways they handled the move from one form of confinement to another and shows how everyday life for former combatant, ex-prisoners is fashioned according to contingent, unpredictable features of the post-war, post-prison landscape. These are mediated through worldviews that developed prior to confinement as well as in response to their particular personal and collective histories of violent conflict, imprisonment and ongoing feelings of dislocation and ontological insecurity. The article contributes to the broadening out of studies of imprisonment effects, focusing on experiences of re-entry while highlighting the importance of pre-prison experience. Based on data from a quite different context (post-conflict Sierra Leone, West Africa) and of a different form (ethnographic rather than interview/survey) the article lends support to the perspective advocated by Jamieson and Grounds that a new paradigm is necessary for thinking about the effects of imprisonment.
Historical criminology and the imprisonment of women in 19th-century Malta
Authors: Knepper Paul , Scicluna Sandra
Published: November 2010

For many criminologists, theory matters more than evidence in historical studies. But can historical criminology really proceed on this basis? In this article, we argue for the importance of primary research, that is, analysis of documents that originate in the period of interest. Using examples from archived documents in a study of women imprisoned in Malta during the 19th century, we address four issues related to history and theory: gaining perspective from unfamiliar places, finding the beginning of historical processes, making discoveries from details, and recovering the significance of forgotten practices. In this, we wish to join a conversation about historical evidence and genealogical accounts in prison history. We will also contribute to the significant, but relatively limited, literature on prisons for women in the 19th century.
Doing and undoing gender in policing
Authors: Chan Janet , Doran Sally , Marel Christina
Published: November 2010

This article assesses the utility of ‘doing gender’ as a framework for examining gender issues in policing. Drawing on a longitudinal study in an Australian police force, the article seeks to explain the persistence of barriers to the integration of female officers after decades of equal employment laws and policies. The interviews make transparent the agency of male and female actors in sustaining or resisting the status quo. While there are real benefits in opening up the ‘doing gender’ framework to draw attention to contestations and challenges to gender hierarchy as suggested by the notion of ‘undoing gender’, the article demonstrates the complexity of gender practices in policing and rejects the posing of equality and difference as mutually exclusive alternatives.
Competition, adaptation and mutation
Authors: Isaacs Bronwyn , Dixon Jane , Banwell Cathy , Seubsman Sam-ang , Kelly Matthew , Pangsap Suttinan
Published: November 2010

The speed at which international supermarkets chains have integrated themselves into Thai diets and food practices is without prior historical precedent. This article uses ethnographic data from Chiang Mai, Thailand, to examine how values surrounding food and food cultures are being sustained, are adapting and are being transformed. It examines both supermarkets and fresh markets as places where the values unfold in different ways. In discussing the sometimes competing, intermingling and mutating values, a Conventions Theory approach is adopted. The theory facilitates a discussion of the monetary, social and cultural evaluations of Chiang Mai’s food markets. In doing so it is argued that the conventions theoretical approach could usefully be extended from western settings to take account of non-western development trajectories and culture-economy interdependencies.
In the name of the child
Authors: Zivkovic Tanya , Warin Megan , Davies Michael , Moore Vivienne
Published: November 2010

This paper investigates the ways in which ‘the child’ is positioned in obesity debates and, in doing so, examines the discursive relations between childhood obesity, mothering and child neglect. Using legal cases of parental neglect and an analysis of representations of obesity in Australian print media, we argue that a particular constellation of ‘child politics’ in which children are represented as innocent victims of poor parenting is at play. Parenting, however, is a code for mothers and it is their gendered responsibility for food and families for which they are now being held legally culpable in cases of neglect. The relationship between children and mothers has become the focus of moral discourses around childhood obesity, containing contradictory elements of innocence and risk, responsibility and danger. The intersection of child politics, mothering and individualized responsibility not only illuminates the ways in which gender is absent yet centrally implicated in obesity debates and policy, but also highlights how models of neoliberal governance encompass both State and decentralized forms of power in their attempt to regulate excess bodies.
Humanitarian welfare values in a changing social environment: A survey of social work undergraduate students in Beijing and Shanghai
Authors: Lou Vivian WQ , Pearson Veronica , Wong Yu C
Published: November 2010

• Summary: Internationally accepted social work values are based on ideas about rights, social justice and equitable resource distribution. Does social work education in China embody similar values? Are these values influenced by culture and the current political/economic environment? The research posed three questions. Do social work students studying in metropolitan China support humanitarian welfare values? Are values affected by demographic backgrounds? Does social work education enhance humanitarian values? A self-administered, standardized questionnaire was distributed in 26 classes of social work students studying in seven universities in Beijing and Shanghai ( n = 1328).

• Findings: Students do not support humanitarian welfare values strongly; and a decrease in these values was observed in senior students. Significant differences in values were found based on gender and on rural/urban origins. Female students were more likely to agree with humanitarian value statements; rural and urban students tended to agree more with values from which they had potential to benefit.

• Applications: Social work knowledge and skills rather than values maybe more immediately relevant to Chinese society. However, independent professional practitioners need a solid foundation of professional values to inform practice and standardize the social work role. There needs to be an ongoing debate in China involving social work educators and practitioners about values and their relation to Chinese society, the ways in which they are influenced by non-Chinese cultures; and how to infuse these consistently into social work curricula in Chinese universities.
A community engagement orientation among people with a history of substance misuse and incarceration
Authors: Redman Dina
Published: November 2010

• Summary: Community engagement, or acting on behalf of the collective, can provide a variety of rewards. Nonetheless, people who misuse substances are less likely to endorse such goals as making a contribution to society or correcting systemic inequities. As people modify their use of drugs or alcohol, they have been shown to draw purpose from community engagement. This mixed methods study examined contributors to a community engagement orientation among 68 respondents with a history of substance misuse and incarceration.

• Findings: In the initial qualitative analysis, four themes emerged related to the respondents’ sense of purpose in life. The theme most frequently mentioned, community engagement, is the focus of this study. Discriminant analyses revealed that those endorsing community engagement goals were older at the onset of heavy drinking, more likely to have received public assistance, more highly educated, as were their mothers, manifested greater self-esteem, and had previously been involved in an organization addressing community concerns.

• Applications: Social workers might assist clients in identifying and manifesting what they believe to be their purpose in life, with particular attention to community engagement. In this way, they may utilize the wisdom gained from challenging experiences to benefit others and bring about social change.
Aboriginal organizational response to the need for culturally appropriate services in three small Canadian cities
Authors: Sookraj Dixon , Hutchinson Peter , Evans Michael , Ann Murphy Mary ,   The Okanagan Urban Aboriginal Health Research Collective
Published: November 2010

• Summary: This component of a larger participatory qualitative case study investigated how urban Aboriginal human service organizations respond to the needs of the growing Aboriginal populations residing in three small cities in the Interior region of British Columbia, Canada. The study focused specifically on the challenges that the organizations experienced in delivering health and social services, and in facilitating access to mainstream services. Semi-structured interviews were conducted with eight senior administrators from seven urban Aboriginal organizations.

• Findings: Participants reported numerous barriers to delivering adequate and culturally appropriate services. Their organizations were challenged to provide a complex array of services to a culturally diverse urban Aboriginal population. Moreover, these organizations operated in turbulent economic, institutional and political environments, which presented additional challenges in several areas: recruiting and retaining qualified Aboriginal staff; securing funding; meeting different and conflicting accountability requirements; using political influence; and linking with both mainstream organizations and local Aboriginal communities.

• Applications: Fundamental tensions between the existing specialized and expert-based, mainstream system and Aboriginal service providers’ holistic approach to well-being are apparent. Implications for future research, policy and practice needed to promote the development of culturally appropriate and responsive services are discussed.
Issues of Gender, Reflexivity and Positionality in the Field of Disability
Authors: Ahmed Dunya Ahmed Abdulla , Hundt Gillian Lewando , Blackburn Clare
Published: November 2010

This article examines how the social and cultural context influence the way in which field research methods are utilized. Research methods need to be modified to meet the sensibilities and sensitivities of particular social groups and settings. Through a reflexive analysis of a research study on the lives of visually impaired young people and adults in Bahrain, this article discusses how gender, religion and culture need to be taken account of. It also discusses how the research process needed to take account of the participants’ disabilities. It examines the issues of research access, informed consent, researcher’s dress, confidentiality, research location, and time. It highlights how the gender of the researcher was constraining in some gender segregated educational settings in a Muslim society. The article engages with the researcher’s positionality through reflexive discussion.
Living the Multiracial Experience
Authors: Jackson Kelly Faye
Published: November 2010

The growing presence and visibility of mixed race persons in the US demands that social workers critically examine and understand the complexity of multiracial identity. This qualitative investigation examined the narratives of ten multiracial adults about their identity experiences living as multiracial persons. Utilizing paradigmatic analysis of narratives, five major themes emerged. Four of these themes correspond to categories found in existing multiracial scholarship, and include: (1) Shifting racial/ethnic expressions; (2) Racial/ethnic ambiguity; (3) Feeling like an outsider; and (4) Seeking community. The final theme, (5) Racial resistance, contributes new knowledge to our understanding of how multiracial individuals respond to societal pressures to conform to traditional means of categorizing others by race. Findings from this study confirm a collective multiracial experience; one with direct ties to the social and environmental pressures associated with having a multifaceted identity in a color-conscious society. Practice implications and directions for future research are offered.
An Invitation to Dialogue
Authors: Fouché Christa , Light Glenda
Published: November 2010

In the context of discussions about the potential of collaborative research, a practice-based project was implemented in Auckland, New Zealand during 2006 and 2007, aimed to help develop a culture of enquiry among practitioners in social service. One design variable in this project was the World Café, a conversational process that helps groups to engage in constructive dialogue around critical questions, to build personal relationships, and to foster collaborative learning. In relation to other collaborative approaches, the World Café is powerful in terms of the use of cross-pollination of ideas through evolving rounds of information exchange and the use of a café-style social context that allows the sharing of information in an equitable and non-threatening manner. This article reports on the design and implementation of a World Café approach, located in the philosophy of appreciative inquiry, through ‘Café Hear and Now’. The authors reflect on the perceived value of this initiative and invite dialogue on the implementation of the World Café in social work research.
To Offer Hope You Must Have Hope
Authors: Flesaker Keri , Larsen Denise
Published: November 2010

As women on parole and probation transition from correctional facilities to the community, they face many threats to reintegration. Reintegration counsellors offer support to individuals on parole and probation who are re-entering the community. Working closely with a marginalized population places counsellors at risk for burnout and hopelessness. Research indicates that hope can serve as a sustaining and motivating factor when facing difficult working contexts. Further, a large body of research consistently confirms the importance of hope in the human change process, both for clients and clinicians. The current study investigated how reintegration counsellors fostered and maintained hope in their work, including their personal descriptions of hope. Employing Merriam’s (2002) basic interpretive inquiry, five reintegration counsellors participated in semi-structured interviews about their work experiences. Thematic analysis indicated that hope played an important role in these counsellors’ experiences of work and their belief in their clients. The overarching theme of the findings, Maintaining a Hope-Seeking Orientation, elucidates the complexity of maintaining a hope-seeking orientation in the challenging context of reintegration counselling. Specifically, participants in this study were understood to hold a hope-seeking orientation to their worklife that included, viewing life as a journey, maintaining a hopeful perspective, holding ‘down-to-earth’ expectations, and viewing hope-seeking as a learnable skill. Participants associated hope with both motivation and meaning, believing that hope was a necessary ingredient in their work and a resource to combat work-related exhaustion. Implications for counselling include sustaining hope at work through a variety of means, including perspective change.
Equality, adequacy, and stakes fairness: Retrieving the equal opportunities in education approach
Authors: Jacobs Lesley A.
Published: November 2010

Two approaches to making judgments about moral urgency in educational policy have prevailed in American law and public policy. One approach holds that educational policy should aspire to realizing equal opportunities in education for all. The other approach holds that educational policy should aspire to realizing adequate opportunities in education for all. Although the former has deep roots in American culture and its jurisprudence, a common narrative is that in recent years the equal opportunities approach has been displaced by the educational adequacy approach, which is said both to have enjoyed much greater success in the school financing litigation as well as to be theoretically more defensible. The present article is designed to make a contribution to the retrieval of the equal opportunities approach. It does so by sketching out a theory of equal opportunities in education organized around the idea of stakes fairness that can withstand the criticisms often made of that approach and by showing how that theory is better able than the educational adequacy approach to address the fairness of a more robust educational policy agenda that extends beyond school financing.
Millennia of discord: The controversial educational program of Isocrates
Authors: Marsh Charles
Published: November 2010

Five years ago in Theory and Research in Education, James R. Muir fired a new salvo in the debate regarding the merits of Isocrates’ educational program, a controversy that has endured for more than two millennia. Was the Isocratean program misguided and lowbrow, as in the estimations of Plato and Aristotle — or was it the most successful program of classical education, as in the later estimations of Cicero and Quintilian? Was Isocrates himself a middling intellect, as Marrou claims, or, worse, a progenitor of Hitler’s Third Reich, as Vitanza maintains — or was he the founder of modern liberal arts education, as Corbett and Welch believe? To date, the debate has dealt more with the reputation than the details of Isocrates’ program. In hopes of shedding additional light on the controversy, this article draws upon Isocrates’ own essays to present the goals, curriculum, and methods of his educational program.
Enlivening the curriculum: The power of philosophical inquiry
Authors: Knight Sue , Collins Carol
Published: November 2010

In this article we argue for the necessity of far-reaching change in school curricula and pedagogy. More particularly, we argue that developing students’ understanding and engagement in the disciplines which make up the school curriculum requires an unearthing of the philosophical issues underlying science, mathematics, the arts, geography, history, and so on. This means that philosophical inquiry must be embedded in every curriculum area. While at first sight this task might appear unattainable, we go on to illustrate by means of detailed examples how the goal might be realized and point to theoretical and empirical evidence to support this contention.
The Role of Endarterectomy and Stenting in the Management of Carotid Artery Stenosis: A 5-Year Delphi Survey
Authors: Malik Zeeshan , Shalhoub Joseph , Hettige Roland , Davies Alun H
Published: November 2010

Introduction: Ambiguity in the literature concerning potential benefits of carotid artery stenting (CAS) as an alternative to carotid endarterectomy (CEA) necessitated a 5-year Delphi-type survey, gauging the changing views over this period of relevant experts undertaking carotid intervention. Methods: Delphi surveys performed in 2004 and 2009 involved 2 rounds of questions combined with feedback of results from the first round between them. The questionnaire was e-mailed to UK vascular surgeons, neurosurgeons, interventional radiologists, and cardiologists. Results: In 2004 and 2009, the second round response rates were 69% and 51%, respectively. Over 5 years, there was a statistically significant reduction in support for ‘‘general anesthesia risk’’ and ‘‘contralateral occlusion’’ as indications for CAS and views that CAS ‘‘increased patient satisfaction’’ and ‘‘decreased the length of hospital stay.’’ Concerning the impact of recent trials on the professionals’ treatment routines for symptomatic and asymptomatic patients with carotid disease, 65.8% and 76.3%, respectively, had not changed their overwhelming non-CAS routines, with 32.9% and 19.7% saying clinical trial results moved them toward CEA. Conclusions: A 2009 survey of vascular experts found no increase in preference for CAS as a treatment option for advanced carotid bifurcation atherosclerosis. This, in combination with the lack of change from and indeed move toward the ‘‘gold-standard’’ CEA, demonstrates a general decline in confidence with CAS.
Malignancy Risk in Vasculitis
Authors: Kermani Tanaz A. , Warrington Kenneth J. , Amin Shreyasee
Published: November 2010

The vasculitides encompass a rare subset of autoimmune diseases. Reports of the concurrent association of malignancies with some forms of vasculitis raise the possibility that patients with certain types of vasculitis may be at increased risk of cancer. Conversely, some forms of vasculitis may be a manifestation of malignancy. We review cancer risk in patients with large vessel vasculitis (giant cell arteritis and Takayasu arteritis), polyarteritis nodosa, and the circulating antineutrophil cytoplasmic antibodies (ANCA)-associated vasculitides. In addition we discuss vasculitis as a paraneoplastic phenomenon, highlighting polyarteritis nodosa in association with hairy cell leukemia and reviewing the most common vasculitic manifestation of cancer, cutaneous vasculitis.
A Self-Regulatory Mechanism for Personality Trait Stability
Authors: Gallagher Patrick , Fleeson William , Hoyle Rick H.
Published: November 2010

Despite the considerable influence of situational factors and the resulting variability in behavior, individuals maintain stable average ways of acting. The purpose of the current research was to investigate one possible explanation for this stability. It was hypothesized that behaviors that are at levels different from the actor’s average trait levels ( contra-trait behaviors) demand more effort, or self-control, than do trait-typical behaviors. In Study 1, extraverted participants who acted at contra-trait levels reported their behaviors as more effortful, and this effect grew stronger over time. In addition, in a subsequent activity, observers rated extraverts who had acted contra-trait as behaving more extraverted, suggesting that fatigue from sustaining contra-trait behaviors may result in subsequent behaviors returning to trait-typical levels. In Study 2, participants reported on contextualized behaviors for 7 days and rated contra-trait behaviors as more effortful than trait-typical behaviors. This effect only held among nonhabitual behaviors, implicating self-control processes.
Nilotinib is effective in patients with chronic myeloid leukemia in chronic phase after imatinib resistance or intolerance: 24-month follow-up results
Authors: Kantarjian Hagop M. , Giles Francis J. , Bhalla Kapil N. , Pinilla-Ibarz Javier , Larson Richard A. , Gattermann Norbert , Ottmann Oliver G. , Hochhaus Andreas , Radich Jerald P. , Saglio Giuseppe , Hughes Timothy P. , Martinelli Giovanni , Kim Dong-Wook , Shou Yaping , Gallagher Neil J. , Blakesley Rick , Baccarani Michele , Cortes Jorge , le Coutre Philipp D.
Published: November 2010

Nilotinib is a potent selective inhibitor of the BCR-ABL tyrosine kinase approved for use in patients with newly diagnosed chronic myeloid leukemia in chronic phase (CML-CP), and in CML-CP and CML-accelerated phase after imatinib failure. Nilotinib (400 mg twice daily) was approved on the basis of the initial results of this phase 2 open-label study. The primary study endpoint was the proportion of patients achieving major cytogenetic response (CyR). All patients were followed for ≥ 24 months or discontinued early. Of 321 patients, 124 (39%) continue on nilotinib treatment. Overall, 59% of patients achieved major CyR; this was complete CyR (CCyR) in 44%. Of patients achieving CCyR, 56% achieved major molecular response. CyRs were durable, with 84% of patients who achieved CCyR maintaining response at 24 months. The overall survival at 24 months was 87%. Adverse events were mostly mild to moderate, generally transient, and easily managed. This study indicates that nilotinib is effective, with a manageable safety profile, and can provide favorable long-term benefits for patients with CML-CP after imatinib failure. This trial was registered at www.clinicaltrials.gov as #NCT00109707.
Silencing of the inhibitor of DNA binding protein 4 (ID4) contributes to the pathogenesis of mouse and human CLL
Authors: Chen Shih-Shih , Claus Rainer , Lucas David M. , Yu Lianbo , Qian Jiang , Ruppert Amy S. , West Derek A. , Williams Katie E. , Johnson Amy J. , Sablitzky Fred , Plass Christoph , Byrd John C.
Published: November 2010

Inhibitor of DNA binding protein 4 (ID4) is a member of the dominant-negative basic helix-loop-helix transcription factor family that lacks DNA binding activity and has tumor suppressor function. ID4 promoter methylation has been reported in acute myeloid leukemia and chronic lymphocytic leukemia (CLL), although the expression, function, and clinical relevance of this gene have not been characterized in either disease. We demonstrate that the promoter of ID4 is consistently methylated to various degrees in CLL cells, and increased promoter methylation in a univariable analysis correlates with shortened patient survival. However, ID4 mRNA and protein expression is uniformly silenced in CLL cells irrespective of the degree of promoter methylation. The crossing of ID4+/− mice with Eμ-TCL1 mice triggers a more aggressive murine CLL as measured by lymphocyte count and inferior survival. Hemizygous loss of ID4 in nontransformed TCL1-positive B cells enhances cell proliferation triggered by CpG oligonucleotides and decreases sensitivity to dexamethasone-mediated apoptosis. Collectively, this study confirms the importance of the silencing of ID4 in murine and human CLL pathogenesis.
Conserved charged amino acid residues in the extracellular region of sodium/iodide symporter are critical for iodide transport activity
Authors: Li Chia-Cheng , Ho Tin-Yun , Kao Chia-Hung , Wu Shih-Lu , Liang Ji-An , Hsiang Chien-Yun
Published: November 2010

Background

Sodium/iodide symporter (NIS) mediates the active transport and accumulation of iodide from the blood into the thyroid gland. His-226 located in the extracellular region of NIS has been demonstrated to be critical for iodide transport in our previous study. The conserved charged amino acid residues in the extracellular region of NIS were therefore characterized in this study.

Methods

Fourteen charged residues (Arg-9, Glu-79, Arg-82, Lys-86, Asp-163, His-226, Arg-228, Asp-233, Asp-237, Arg-239, Arg-241, Asp-311, Asp-322, and Asp-331) were replaced by alanine. Iodide uptake abilities of mutants were evaluated by steady-state and kinetic analysis. The three-dimensional comparative protein structure of NIS was further modeled using sodium/glucose transporter as the reference protein.

Results

All the NIS mutants were expressed normally in the cells and targeted correctly to the plasma membrane. However, these mutants, except R9A, displayed severe defects on the iodide uptake. Further kinetic analysis revealed that mutations at conserved positively charged amino acid residues in the extracellular region of NIS led to decrease NIS-mediated iodide uptake activity by reducing the maximal rate of iodide transport, while mutations at conserved negatively charged residues led to decrease iodide transport by increasing dissociation between NIS mutants and iodide.

Conclusions

This is the first report characterizing thoroughly the functional significance of conserved charged amino acid residues in the extracellular region of NIS. Our data suggested that conserved charged amino acid residues, except Arg-9, in the extracellular region of NIS were critical for iodide transport.
The role of HIF-1 in up-regulating MICA expression on human renal proximal tubular epithelial cells during hypoxia/reoxygenation
Authors: Luo Lei , Lu Jun , Wei Liang , Long Dan , Guo Jia Y , Shan Juan , Li Fu S , Lu Ping Y , Li Ping Y , Feng Li
Published: November 2010

Background

Human major histocompatibility complex class I-related chain A (MICA) plays a dual role in adaptive and innate immune responses. Increasing evidence demonstrates that MICA is closely correlated with acute and chronic kidney allograft rejection. Therefore, understanding the activation mechanisms of MICA is important in kidney transplantation. We previously demonstrated that ischemia/reperfusion injury (IRI) could up-regulate MICA expression on mouse kidney allografts. Since hypoxia-inducible factor-1 (HIF-1) is the master regulator of cellular adaptive responses to hypoxia during IRI, here we investigate whether HIF-1 could up-regulate MICA expression and its influence on NK cell cytotoxicity.

Results

We find that HIF-1alpha plays an important role in up-regulating MICA expression, inducing IFNgamma secretion and NK cell cytotoxicity during hypoxia/reoxygenation. First, we generated a HIF-1alphaDELTAODD-expressing adenovirus to stably and functionally express HIF-1alpha in human renal proximal tubular epithelial (HK-2) cells under normoxia conditions. HIF-1alpha over-expression in HK-2 cells induces MICA expression and enhances NK cell cytotoxic activity towards cells that express HIF-1alpha. Second, we used a hypoxia/reoxygenation cell model to simulate IRI in vitro and found that the suppression of HIF-1alpha by RNAi induces down-regulation of MICA expression and inhibits NK cytotoxicity. In antibody blocking experiments, an anti-MICA mAb was able to down-regulate NK cell cytotoxic activity towards HK-2 cells that over-expressed HIF-1alpha. Moreover, when NK cells were co-cultured with the HK-2 cells expressing MICA, which was up-regulated by over-expression of HIF-1alpha, there was a significant increase in the secretion of IFNgamma. In the presence of the blocking MICA mAb, IFNgamma secretion was significantly decreased.

Conclusions

These results demonstrate that hypoxia/reoxygenation-promoted MICA expression on HK-2 cells is through a HIF-1 pathway. The increased IFNgamma secretion and enhanced NK cell cytotoxicity was mainly due to the surface expression of MICA induced by over-expression of HIF-1alpha. This study enhances our understanding of MICA activation mechanisms during kidney transplantation and provides insights into how IRI can influence transplant outcome. Moreover, these findings might be also important for developing strategies to reduce the effect of MICA in kidney transplant outcomes in the future.
Imprinted genes show unique patterns of sequence conservation
Authors: Hutter Barbara , Bieg Matthias , Helms Volkhard , Paulsen Martina
Published: November 2010

Background

Genomic imprinting is an evolutionary conserved mechanism of epigenetic gene regulation in placental mammals that results in silencing of one of the parental alleles. In order to decipher interactions between allele-specific DNA methylation of imprinted genes and evolutionary conservation, we performed a genome-wide comparative investigation of genomic sequences and highly conserved elements of imprinted genes in human and mouse.

Results

Evolutionarily conserved elements in imprinted regions differ from those associated with autosomal genes in various ways. Whereas for maternally expressed genes strong divergence of protein-encoding sequences is most prominent, paternally expressed genes exhibit substantial conservation of coding and noncoding sequences. Conserved elements in imprinted regions are marked by enrichment of CpG dinucleotides and low (TpG+CpA)/(2·CpG) ratios indicate reduced CpG deamination. Interestingly, paternally and maternally expressed genes can be distinguished by differences in G+C and CpG contents that might be associated with unusual epigenetic features. Especially noncoding conserved elements of paternally expressed genes are exceptionally G+C and CpG rich. In addition, we confirmed a frequent occurrence of intronic CpG islands and observed a decelerated degeneration of ancient LINE-1 repeats. We also found a moderate enrichment of YY1 and CTCF binding sites in imprinted regions and identified several short sequence motifs in highly conserved elements that might act as additional regulatory elements.

Conclusions

We discovered several novel conserved DNA features that might be related to allele-specific DNA methylation. Our results hint at reduced CpG deamination rates in imprinted regions, which affects mostly noncoding conserved elements of paternally expressed genes. Pronounced differences between maternally and paternally expressed genes imply specific modes of evolution as a result of differences in epigenetic features and a special response to selective pressure. In addition, our data support the potential role of intronic CpG islands as epigenetic key regulatory elements and suggest that evolutionary conserved LINE-1 elements fulfill regulatory functions in imprinted regions.
Transcriptome analysis of a barley breeding program examines gene expression diversity and reveals target genes for malting quality improvement
Authors: Muñoz-Amatriaín María , Xiong Yanwen , Schmitt Mark R , Bilgic Hatice , Budde Allen D , Chao Shiaoman , Smith Kevin P , Muehlbauer Gary J
Published: November 2010

Background

Advanced cycle breeding utilizes crosses among elite lines and is a successful method to develop new inbreds. However, it results in a reduction in genetic diversity within the breeding population. The development of malting barley varieties requires the adherence to a narrow malting quality profile and thus the use of advanced cycle breeding strategies. Although attention has been focused on diversity in gene expression and its association with genetic diversity, there are no studies performed in a single breeding program examining the implications that consecutive cycles of breeding have on gene expression variation and identifying the variability still available for future improvement.

Results

Fifteen lines representing the historically important six-rowed malting barley breeding program of the University of Minnesota were genotyped with 1,524 SNPs, phenotypically examined for six malting quality traits, and analyzed for transcript accumulation during germination using the Barley1 GeneChip array. Significant correlation was detected between genetic and transcript-level variation. We observed a reduction in both genetic and gene expression diversity through the breeding process, although the expression of many genes have not been fixed. A high number of quality-related genes whose expression was fixed during the breeding process was identified, indicating that much of the diversity reduction was associated with the improvement of the complex phenotype "malting quality", the main goal of the University of Minnesota breeding program. We also identified 49 differentially expressed genes between the most recent lines of the program that were correlated with one or more of the six primary malting quality traits. These genes constitute potential targets for the improvement of malting quality within the breeding program.

Conclusions

The present study shows the repercussion of advanced cycle breeding on gene expression diversity within an important barley breeding program. A reduction in gene expression diversity was detected, although there is diversity still present after forty years of breeding that can exploited for future crop improvement. In addition, the identification of candidate genes for enhancing malting quality may be used to optimize the selection of targets for further improvements in this economically important phenotype.