bluuebunny/crossref_metadata_2025 huggingface dataset:
Neural Crest Lineage Segregation: a Blueprint for Periodontal Regeneration
Authors: Luan X. , Dangaria S. , Ito Y. , Walker C.G. , Jin T. , Schmidt M.K. , Galang M.T. , Druzinsky R.
Published: September 2009

During the recent decade, the periodontal attachment apparatus has become one of the premier areas of the body for the development of novel tissue-engineering strategies. In the present review, we describe a developmental biology approach to characterize current concepts in periodontal regeneration and to discuss strategies for future applications in periodontal therapies. To decipher the developmental make-up of the periodontal region, we have followed the path of the migratory neural crest, since it gives rise to periodontal progenitor tissues, which in turn are subjected to the influence of diverse craniofacial extracellular matrices and peptide growth factors. Based on this developmental perspective, we have conducted a systematic analysis of the factors, progenitor cells, and matrices used in current periodontal tissue-engineering approaches. We propose that the developmental history of a tissue is a highly instructive design template for the discovery of novel bioengineering tools and approaches.
Mesenchymal Stem Cells Derived from Dental Tissues vs. Those from Other Sources: Their Biology and Role in Regenerative Medicine
Authors: Huang G.T.-J. , Gronthos S. , Shi S.
Published: September 2009

To date, 5 different human dental stem/progenitor cells have been isolated and characterized: dental pulp stem cells (DPSCs), stem cells from exfoliated deciduous teeth (SHED), periodontal ligament stem cells (PDLSCs), stem cells from apical papilla (SCAP), and dental follicle progenitor cells (DFPCs). These postnatal populations have mesenchymal-stem-cell-like (MSC) qualities, including the capacity for self-renewal and multilineage differentiation potential. MSCs derived from bone marrow (BMMSCs) are capable of giving rise to various lineages of cells, such as osteogenic, chondrogenic, adipogenic, myogenic, and neurogenic cells. The dental-tissue-derived stem cells are isolated from specialized tissue with potent capacities to differentiate into odontogenic cells. However, they also have the ability to give rise to other cell lineages similar to, but different in potency from, that of BMMSCs. This article will review the isolation and characterization of the properties of different dental MSC-like populations in comparison with those of other MSCs, such as BMMSCs. Important issues in stem cell biology, such as stem cell niche, homing, and immunoregulation, will also be discussed.
Surface Conditioning Influences Zirconia Ceramic Bonding
Authors: Kern M. , Barloi A. , Yang B.
Published: September 2009

Air-abrasion seems to be mandatory for durable resin bonding to zirconia ceramic. Air-abrasion might compromise the ceramic strength by creating surface defects. Therefore, omitting air-abrasion or using reduced air-pressure seems desirable. We tested the null hypotheses that omitting air-abrasion or using reduced air-pressure does not affect zirconia ceramic bonding independent of using primers. Three mechanical surface conditions (polished, air-abraded at 0.05 or at 0.25 MPa) and 4 priming conditions were tested. After different surface conditioning, zirconia ceramic specimens were bonded, and tensile bond strengths were evaluated after water storage for 3 days or for 150 days with additional 37,500 thermal cyclings for artificial aging. Omitting air-abrasion resulted in debonding during artificial aging independent of using primers. The combination of air-abrasion and priming improved long-term resin bonding to zirconia ceramic significantly. With low-pressure air-abrasion, surface roughness was reduced without affecting long-term bond strength, provided that adequate adhesive primers were applied.
Novel RUNX2 Mutations in Chinese Individuals with Cleidocranial Dysplasia
Authors: Zhang C.Y. , Zheng S.G. , Wang Y.X. , Zhu J.X. , Zhu X. , Zhao Y.M. , Ge L.H.
Published: September 2009

Cleidocranial dysplasia (CCD) is an inherited autosomal-dominant skeletal disease caused by heterozygous mutations in the osteoblast-specific transcription factor, RUNX2. We performed mutation analysis of RUNX2 on four unrelated Chinese individuals with CCD. Three novel distinct mutations were detected in the coding region of RUNX2: two missense and one frameshift. These mutations were exclusively clustered within the Runt domain. One missense mutation converts threonine to isoleucine at codon 200 (T200I). The other one substitutes leucine for arginine at codon 225 (R225L), which affects many family members. The frame-shift mutation (214fs) in exon3 leads to the introduction of a translational stop codon at codon 221, resulting in a truncated RUNX2 protein. The reporter gene assays revealed that all the mutants exhibited significantly reduced transactivation activities on the osteocalcin promoter. Our results provide new genetic evidence that mutations involved in RUNX2 contribute to CCD. Abbreviations: AML3, gene encoding acute myeloid leukemia protein 3; bp, base pair; CBFA1, gene encoding core-binding factor 1; CBFβ, gene encoding core-binding factor β; CCD, cleidocranial dysplasia; NLS, nuclear localization signal; OSE2, osteoblast-specific cis-acting element 2; PEBP2A, gene encoding polyoma enhancer binding protein 2A; PST, proline/serine/ threonine-rich domain; Q/A, glutamine-alanine repeat domain; Runt, Runt Homology Domain; RUNX2, the mammalian runt-related genes 2; RUNX2, Runt-related protein 2.
Eph/ephrinB Mediate Dental Pulp Stem Cell Mobilization and Function
Authors: Arthur A. , Koblar S. , Shi S. , Gronthos S.
Published: September 2009

Damage to the dentin matrix instigates the proliferation and mobilization of dental progenitor cells to the injury site, the mechanisms of which are not defined. EphB receptors and ephrin-B ligands expressed within the perivascular niche of dental pulp have been implicated following tooth injury. We propose that elevated levels of ephrin-B1 following injury may prevent the proliferation and migration of dental pulp stem cell (DPSC), while EphB/ephrin-B interaction facilitates odontoblastic differentiation. The migration, proliferation, and differentiation of DPSC in response to Eph/ephrin-B molecules was assessed in an established ex vivo tooth injury model and by in vitro assays for the assessment of colony formation and differentiation. Analysis of our data demonstrated that EphB forward signaling promoted DPSC proliferation, while inhibiting migration. Conversely, reverse signaling enhanced DPSC mineral production. These observations suggest that EphB/ephrin-B molecules are important for perivascular DPSC migration toward the dentin surfaces and differentiation into functional odontoblasts, following damage to the dentin matrix.
Mmp-20 and Klk4 Cleavage Site Preferences for Amelogenin Sequences
Authors: Nagano T. , Kakegawa A. , Yamakoshi Y. , Tsuchiya S. , Hu J.C.-C. , Gomi K. , Arai T. , Bartlett J.D. , Simmer J.P.
Published: September 2009

Mmp-20 and Klk4 are the two key enamel proteases. Can both enzymes process amelogenin to generate the major cleavage products that accumulate during the secretory stage of amelogenesis? We isolated Mmp-20 and Klk4 from developing pig teeth and used them to digest the tyrosine-rich amelogenin polypeptide (TRAP), the leucine-rich amelogenin protein (LRAP), and 5 fluorescence peptides. We characterized the digestion products by LC-MSMS, SDS-PAGE, and C18 RP-HPLC monitored with fluorescence and UV detectors. Mmp-20 cleaves amelogenin sequences after Pro162, Ser148, His62, Ala63, and Trp45. These cleavages generate all of the major cleavage products that accumulate in porcine secretory-stage enamel: the 23-kDa, 20-kDa, 13-kDa, 11-kDa, and 6-kDa (TRAP) amelogenins. Mmp-20 cleaves LRAP after Pro45 and Pro40, producing the two LRAP products previously identified in tooth extracts. Among these key cleavage sites, Klk4 was able to cleave only after His62. We propose that Mmp-20 alone processes amelogenin during the secretory stage.
Histatins Enhance Wound Closure with Oral and Non-oral Cells
Authors: Oudhoff M.J. , van den Keijbus P.A.M. , Kroeze K.L. , Nazmi K. , Gibbs S. , Bolscher J.G.M. , Veerman E.C.I.
Published: September 2009

The role of human saliva in oral wound-healing has never been fully elucidated. We previously demonstrated that parotid-salivary histatins enhance in vitro wound closure. The question remains whether other salivary-gland secretions enhance wound closure, and also the effects of histatins on primary and non-oral cells. Since the presence of histatins is not limited to parotid saliva, we expected to observe wound-closure activity of other salivary-gland secretions. However, here we show that non-parotid saliva does not stimulate wound closure, most probably due to the presence of mucins, since the addition of MUC5B to parotid saliva abolished its effect. Furthermore, we found that histatins stimulated wound closure of (primary) cells of both oral and non-oral origin. This suggests that the cellular receptor of histatins is widely expressed and not confined to cells derived from the oral cavity. These findings encourage the future therapeutic application of histatins in the treatment of all kinds of wounds.
Osteoblast Mechanoresponses on Ti with Different Surface Topographies
Authors: Sato N. , Kubo K. , Yamada M. , Hori N. , Suzuki T. , Maeda H. , Ogawa T.
Published: September 2009

During implant healing, mechanical force is transmitted to osteogenic cells via implant surfaces with various topographies. This study tested a hypothesis that osteoblasts respond to mechanical stimulation differently on titanium with different surface topographies. Rat bone-marrow-derived osteoblastic cells were cultured on titanium disks with machined or acid-etched surfaces. A loading session consisted of a 3-minute application of a 10- or 20-μm-amplitude vibration. Alkaline phosphatase activity and gene expression increased only when the cells were loaded in 3 sessions/day on machined surfaces, regardless of the vibration amplitude, whereas they were increased with 1 loading session/day on the acid-etched surface. The loading did not affect the osteoblast proliferation on either surface, but selectively enhanced the cell spreading on the machined surface. Analysis of the data suggests that osteoblastic differentiation is promoted by mechanical stimulation on titanium, and that the promotion is disproportionate, depending on the titanium surface topography. The frequency of mechanical stimulation, rather than its amplitude, seemed to have a key role.
Personality Judgments Based on Physical Appearance
Authors: Naumann Laura P. , Vazire Simine , Rentfrow Peter J. , Gosling Samuel D.
Published: September 2009

Despite the crucial role of physical appearance in forming first impressions, little research has examined the accuracy of personality impressions based on appearance alone. This study examined the accuracy of observers’ impressions on 10 personality traits based on full-body photographs using criterion measures based on self and peer reports. When targets’ posture and expression were constrained (standardized condition), observers’ judgments were accurate for extraversion, self-esteem, and religiosity. When targets were photographed with a spontaneous pose and facial expression (spontaneous condition), observers’ judgments were accurate for almost all of the traits examined. Lens model analyses demonstrated that both static cues (e.g., clothing style) and dynamic cues (e.g., facial expression, posture) offered valuable personality-relevant information. These results suggest that personality is manifested through both static and expressive channels of appearance, and observers use this information to form accurate judgments for a variety of traits.
Rapidly Declining Unilateral Hearing Within 1 Month in a Newborn With Internal Auditory Canal Stenosis and Facial Palsy
Authors: Lee Inn-Chi , Tsao Chien-Han , Su Pen-Hua , Hu Jui-Ming , Ng Yan-Yan , Chen Jia-Yuh
Published: September 2009

Most newborns with congenital unilateral facial palsy are expected to recover; however, when a patient has hearing loss, underlying developmental ear structure abnormalities should be investigated, particularly when the patient has internal auditory canal stenosis, which is rarely reported in newborns. All cases of internal auditory canal stenosis are accompanied by concomitant unilateral or bilateral hearing loss, but none with progressive hearing loss has been reported. We present the case of a newborn with rapidly declining hearing in the left ear within 1 month after birth. The hearing decline was associated with unilateral facial palsy. Using high-resolution computed tomography (CT) of the temporal bone, we diagnosed the patient with congenital internal auditory canal stenosis. This is the first case detected with progressive hearing loss after birth, which implies that prompt diagnosis and early habilitation are warranted, even when the hearing loss is initially mild.
Life-Course Typology of Adults Who Experienced Sexual Violence
Authors: Draucker Claire , Martsolf Donna
Published: September 2009

Two qualitative methodologies were used to develop a life-course typology of individuals who had been exposed to sexual violence. Interview narratives of 121 adult women and men who participated in qualitative study of women’s and men’s responses to sexual violence provided the data. The authors combined a narrative approach (holistic-content and holistic-form analysis) to describe the life courses of the participants and a qualitative person-oriented approach (cross-case analysis) to identify meaningful subgroups within the total sample. The six groups are as follows: (a) life of turmoil, (b) life of struggles, (c) diminished life, (d) taking control of life, (e), finding peace in life, and (f) getting life back to normal. This work exemplifies a promising strategy for identifying subgroups of violence-exposed individuals within a heterogeneous sample. Such a typology could aid the development of treatment approaches that consider both the substance and the structure of an individual’s life course, rather than target one specific type of violence.
Organizational Newc(ust)omers: Applying Organizational Newcomer Assimilation Concepts to Customer Information Seeking and Service Outcomes
Authors: Fonner Kathryn L. , Timmerman C. Erik
Published: September 2009

The process through which customers resolve uncertainty regarding their participative role in service transactions may be similar to the process that organizational newcomers experience as they gain role clarity and assimilate into organizations.This study applies organizational socialization literature to examine customer socialization, information seeking, role clarity, and service outcomes. Results ( N = 328) indicate that (a) customers’ perceived social costs have a stronger association with information seeking than does felt need for information, (b) overt and indirect information seeking is related to role clarity, and (c) role clarity mediates relationships between overt and third-party information seeking tactics and service outcomes.The report concludes with discussion of the benefits of applying organizational socialization frameworks to service contexts.
Editorial
Authors: Kumar Manasi , Burman Erica
Published: September 2009

We welcome readers to the second special issue (11.2) of the Journal of Health Management in 2009. We hope the readers find the articles and various reviews enriching and provocative, both in terms of the range of ideas and critical approaches addressed. The key theme of this double issue concerns the political limits of mega-development projects such as the Millennium Development Goals (MDGs). The primary focus of the articles collected here is to provide an insightful, constructive and in-depth critique of the United Nations (UN) MDGs along with critical deliberations on their short- and long-term implications not only for health management but also for a wide range of issues around development and social change.
Disability and the Millennium Development Goals
Authors: Ghai Anita
Published: September 2009

The objective of this article is to locate disability issues within the discourse of the Millennium Development Goals (MDGs). The idea is to question the failure of the goals addressing disability. MDGs cannot work as a universal remedy. It is critical to foreground the meaning of disability and underscore the reasons for the disabled people's absence from the agenda of the MDGs. Further, I discuss the ways in which state policy has addressed ‘disability’ in a globalising context. Finally, I outline the paradox of identity politics and its nuances based upon an understanding of the issues and related questions from my own experiences as a disabled Indian woman, having to contend with the existential realities of a visible physical disability. The plea is to expand the democratic space to ensure that the rights and needs of disabled people within the MDGs discourse are given due consideration.
Bottlenecks and Benevolence
Authors: Harman Sophie
Published: September 2009

This article looks at how Goal 6 of the United Nations (UN) Millennium Development Goals (MDGs) impacts on the well-being of the people affected by Human Immunodeficiency Virus/ Acquired Immune Deficiency Syndrome (HIV/AIDS). The focus is on a specific aspect : how the aid emphasised by Goal 6 is channelled towards community groups responding to the HIV/AIDS crisis. It does so by exploring the institutional mechanisms used by one of the key international organisations involved in the realisation of the MDGs—the World Bank and its Multi-Country HIV/AIDS Programme (MAP) in Kenya, Tanzania and Uganda. The article explores the role of local government, rivalry between different forms of civil society organisations, the problems associated with effective delivery and community feedback, donor responses to these problems and how these factors impact upon the immediate and long-term realisation of Goal 6, and the position of communities within it. Key to which are themes of conditionality and divisions between implementation and decision-making. The article is based upon extensive qualitative research into MAP in East Africa.
Frustrated Potential, False Promise or Complicated Possibilities? Empowerment and Participation Amongst Female Health Volunteers in South Africa
Authors: Campbell Catherine , Gibbs Andy , Nair Yugi , Maimane Sbongile
Published: September 2009

We present a longitudinal case study of lay women's participation in a project seeking to facilitate home-based care of people dying of AIDS in a rural community in South Africa, drawing on four sets of interviews conducted with volunteers over a five-year period. We link participation in the project to three dimensions of women's agency: their knowledge and skills, their confidence; and their personal experiences of efficacy. We show that whilst the experience of participation enhanced each of these dimensions of volunteers’ agency at various stages of the project, the empowerment that did take place appeared to be limited to women's project-related roles, rather than generalising to other areas of their lives beyond the project. The project had limited impact on women's ability to negotiate condom use with husbands, to assert themselves in relation to male project leaders and to become more involved in wider community decision-making and leadership. We discuss three possible interpretations of our findings: (i) that greater empowerment might have occurred had the project run for a longer time period; (ii) that whilst such projects play a vital role in providing services, the more general ‘empowerment via participation’ agenda is a false promise in highly marginalised communities; or (iii) that whilst generalised positive impacts of such projects on volunteers are hard to track, such projects do open up glimpses of increased agency for many women. These might have positive but unpredictable results in ways that defy formulation in linear conceptualisations of social transformation and development, understood in terms of clearly observable and measurable inputs and outputs.
Listening to Oral Traditions in a Re-searching for Praxis in a Non-western Context
Authors: Eskell-Blokland Linda Marie
Published: September 2009

The relevance and appropriateness of western oriented psychology in practice and research is a concern in developing and non-western contexts. It is difficult to address this problem from any alternative position other than the western academic frame if one is situated in a tertiary educational institution in South Africa. In acknowledgement, this article explores the academic context including some local voices from the field in a search for possible congruent research methodologies, which may echo knowledge systems of the traditions of the local context in South Africa and its broader context in the continent. Constraining factors to the development of an appropriate praxis have been suggested to include epistemological issues, western academic hegemony and the perceived elitism of psychology as a discipline. In particular, this article explores the adoption of a narrative literary stance for research in psychology. Literary theory and discussions of the narrative from Bakhtin's writings are drawn on in an attempt to bridge a perceived epistemological divide between local traditional knowledge systems and western academia. From this perspective the oral tradition of Africa is considered at the interface of local and western knowledge around healing /helping traditions.
Danger and Disease in Sex Education
Authors: Macleod Catriona
Published: September 2009

The United Nations Development Programme's (UNDP) Millennium project argues for the importance of sexual and reproductive health in the achievement of all Millennium Development Goals (MDGs). Sex education programmes, aimed principally at the youth, are thus emphasised and are in line with the specific MDGs of reducing the incidence of HIV and improving maternal health. In this article, I analyse recent South African sex education and Life Orientation (a learning area containing sex education) manuals. Danger and disease feature as guiding metaphors for these manuals, with early reproduction and abortion being depicted as wholly deleterious and non-normative relationships leading to disease. I argue, first, that these renditions ignore well-designed comparative research that calls into question the easy assumption of negative consequences accompanying ‘teenage pregnancy’ and abortion, and, second, that the persistence of danger and disease in sex education programmes is premised on a discourse of ‘adolescence’. ‘Adolescence’ as a concept is already saturated with the colonialist foundation of phylogeny re-capitulating ontogeny. Individual development is interwoven with collective development with the threat of degeneration implied in both. This interweaving allows for the instrumentalist goal of sex education in which social changes are sought through changing individuals’ sexual attitudes and behaviour.
The Millennium Development Goalposts
Authors: Bradbury Jill , Clark Jude
Published: September 2009

The United Nations’ Millenium Development Goals (MDGs) work in pervasive and powerful ways in the international imagination, by naturalising a strategic set of goals, indicators and targets, and in doing so, either opening up, or precluding and prescribing particular possibilities for understanding the state of the world and people's experiences. Our departure point for exploring the need for alternative research routes is therefore an engagement with the conceptualisation of ‘development’, the hopeful product of the 2015 target. This conceptual critique is three-fold: 1. There is a slippage in the discourse of the MDGs between ‘poverty’, ‘health’ and ‘development’ and consequently, the relations between different goals are poorly theorised. 2. There is an absence (or extreme paucity) of structural analysis. 3. While people are surely the centre of the developmental goals, in their formulation there is a remarkable absence both of specific groups of people and any conceptualisation of personhood in a more universal human sense. An alternative framework for understanding development and the relations between structure and agency is explored by theorising the themes of gender, national identity and childhood/youth. We then suggest that narrative methodologies may offer a productive research trajectory.
Universal Primary Education for All Towards Millennium Development Goal 2
Authors: Rahman Md. Obaidur , Islam Mohammad Tanvirul
Published: September 2009

Bangladesh, in theory and law, advocates equity of access to largely uniform, mass-oriented and universal system of education. This objective remains unfulfilled owing to the lack of commitment of all concerned to reach the goal of Education for All. Although the aggregate performance indicators (e.g. gross enrollment rate) for the primary education sub-sector has been relatively satisfactory in 2000s compared to the situations in 1990s. Beset with numerous problems, the education system is at once discriminatory and inconsistent. The standard of education is on the decline. The absence of effective quality control mechanisms and non-standardisation of the core content of basic learning materials make the education scenario even less satisfactory. More then half of the population in Bangladesh is denied the right to education. In this backdrop, this article critically examines government commitments for universal primary education for all by 2015 and the present situation of primary education sub sector. This article focused on the problem, challenges and policy issues to achieve the second goal of MDGs.
This Benevolent Hand Gives You Soap
Authors: Plyushteva Anna
Published: September 2009

In October 2008, the first Global Handwashing Day was celebrated internationally. It was promoted as the highlight of a global effort to spread the practice of washing hands with soap, reducing the incidence of diarrhoeal disease and saving hundreds of thousands of lives. However, the objectives and strategies of the public-private partnership (PPP) behind this initiative, which includes the three biggest global producers of soap, have not received sufficient scrutiny. This article offers a critical reassessment of the Global Handwashing Day, its origins and its implications, and challenges the campaign's significance for its alleged beneficiaries and benefactors.
Clean Development Mechanism and Least Developed Countries: Changing the Rules for Greater Participation
Authors: De Lopez Thanakvaro , Tin Ponlok , Iyadomi Keisuke , Santos Sergio , McIntosh Bridget
Published: September 2009

The clean development mechanism (CDM) of the Kyoto Protocol is designed not only to mitigate greenhouse gas emissions (GHG) but also to contribute locally to sustainable development. As a market-based mechanism, CDM has the potential to channel private investments into development activities with economic, social, and environmental benefits. Unfortunately, investments have tended to flow where CDM activities provide higher returns with limited economic and political risks, that is, outside of least developed countries (LDCs).To date, only a handful of LDCs have been able to participate in the CDM. This article discusses opportunities for modifying the CDM rules to provide more opportunities for LDCs. Regulatory reforms, technical assistance programs, and direct registration and certification of CDM activities in LDCs by the UNFCCC Secretariat may help foster CDM activities in LDCs . As negotiations regarding the post-2012 climate regime are afoot, an overhaul of the CDM toward a mechanism more friendly to LDCs is necessary.
Sex Differences in Sum Scores May Be Hard to Interpret
Authors: Slof-Op 't Landt M.C.T. , van Furth E.F. , Rebollo-Mesa I. , Bartels M. , van Beijsterveldt C.E.M. , Slagboom P.E. , Boomsma D.I. , Meulenbelt I. , Dolan C.V.
Published: September 2009

In most assessment instruments, distinct items are designed to measure a trait, and the sum score of these items serves as an approximation of an individual’s trait score. In interpreting group differences with respect to sum scores, the instrument should measure the same underlying trait across groups (e.g., male/female, young/old). Differences with respect to the sum score should accurately reflect differences in the latent trait of interest. A necessary condition for this is that the instrument is measurement invariant. In the current study, the authors illustrate a stepwise approach for testing measurement invariance with respect to sex in a four-item instrument designed to assess disordered eating behavior in a large epidemiological sample (1,195 men and 1,507 women). This approach can be applied to other phenotypes for which group differences are expected. Any analysis of such variables may be subject to measurement bias if a lack of measurement invariance between grouping variables goes undetected.
BSC Vision Towards Exascale
Authors: Labarta Jesús , Ayguadé Eduard , Valero Mateo
Published: September 2009

This paper provides the vision of the Barcelona Supercomputing Center towards exascale computing. We believe that it is key to have unified views of future computer systems, looking at the good ideas, developments, and practices from the past and applying them at the scalability levels we want to consider. The programming model is of Alexander’s sword used to break the Gordian knot of exascale systems based on massive multicore architectures. The implementation of the programming model should decouple the way programs are written by the user (parallelism, address spaces, etc.) and executed by the runtime (execution vehicles, memory containers, malleability and load balancing, fault tolerance, etc.) on a specific target architecture. At the application level, it will be crucial to ensure that application porting is going to guarantee their survival for some decades or their clean upgrade to the foreseeable explosion of hardware platforms. Performance tools and analysis practices are in their infancy with regard to providing the required exascale support. BSC would like to contribute with this vision and ongoing efforts to the holistic exascale initiative.
Slouching Towards Exascale
Authors: Lusk Ewing
Published: September 2009

One question before the high-performance computing community is “How will application developers write code for exascale machines?” At this point it looks like they might be riding a rough beast indeed. This paper is a brief assessment of where we stand now with respect to writing programs for our largest supercomputers and what we should do next. MPI is likely to remain a critical part of the programming infrastructure as we move towards exascale, but more is needed, in particular a robust, portable, and effective standard for parallel programming within a single address space, perhaps for heterogeneous processors. Formal methods provide the only truly scalable approach to developing correct code in this complex programming environment.
Role of detonation gun spray Cr3C2–NiCr coating in improving high temperature corrosion resistance of SAE–213–T22 and SAE–347H steel in presence of Na2SO4–82%Fe2(SO4)3 salt deposits
Authors: Kaur M. , Singh H. , Prakash S.
Published: September 2009

Cr3C2–NiCr coatings were sprayed on SAE–213–T22 and SAE–347H boiler steels by detonation gun spray process. High temperature corrosion studies were conducted on the uncoated as well as detonation gun sprayed specimens in a molten salt environment at 700°C under cyclic conditions. The molten salt comprising Na2SO4–82%Fe2(SO4)3 was applied on the specimens as a deposit. The weight change technique was used to establish kinetics of the corrosion. X-ray diffraction, field emission scanning electron microscopy/energy dispersive spectroscopy and X-ray mapping techniques were used to analyse the corrosion products. SAE–213–T22 steel suffered an accelerated corrosion in the form of intense spalling of its oxide scale, whereas SAE–347H steel exhibited only marginal spallation in the form of fine powder. The Cr3C2–NiCr coating showed good adherence to the boiler steels during the exposure with no tendency for spallation of its oxide scale. The coating was found to be successful in developing resistance against hot corrosion in the molten salt environment, which may be attributed to the formation of oxides of nickel and chromium.
Diverse marrow stromal cells protect CLL cells from spontaneous and drug-induced apoptosis: development of a reliable and reproducible system to assess stromal cell adhesion-mediated drug resistance
Authors: Kurtova Antonina V. , Balakrishnan Kumudha , Chen Rong , Ding Wei , Schnabl Susanne , Quiroga Maite P. , Sivina Mariela , Wierda William G. , Estrov Zeev , Keating Michael J. , Shehata Medhat , Jäger Ulrich , Gandhi Varsha , Kay Neil E. , Plunkett William , Burger Jan A.
Published: September 2009

Marrow stromal cells (MSCs) provide important survival and drug resistance signals to chronic lymphocytic leukemia (CLL) cells, but current models to analyze CLL–MSC interactions are heterogeneous. Therefore, we tested different human and murine MSC lines and primary human MSCs for their ability to protect CLL cells from spontaneous and drug-induced apoptosis. Our results show that both human and murine MSCs are equally effective in protecting CLL cells from fludarabine-induced apoptosis. This protective effect was sustained over a wide range of CLL–MSC ratios (5:1 to 100:1), and the levels of protection were reproducible in 4 different laboratories. Human and murine MSCs also protected CLL cells from dexamethasone- and cyclophosphamide-induced apoptosis. This protection required cell–cell contact and was virtually absent when CLL cells were separated from the MSCs by micropore filters. Furthermore, MSCs maintained Mcl-1 and protected CLL cells from spontaneous and fludarabine-induced Mcl-1 and PARP cleavage. Collectively, these studies define common denominators for CLL cocultures with MSCs. They also provide a reliable, validated tool for future investigations into the mechanism of MSC–CLL cross talk and for drug testing in a more relevant fashion than the commonly used suspension cultures.
Incorporating multiple interventions in meta-analysis: an evaluation of the mixed treatment comparison with the adjusted indirect comparison
Authors: O'Regan Christopher , Ghement Isabella , Eyawo Oghenowede , Guyatt Gordon H , Mills Edward J
Published: September 2009

Background

Comparing the effectiveness of interventions is now a requirement for regulatory approval in several countries. It also aids in clinical and public health decision-making. However, in the absence of head-to-head randomized trials (RCTs), determining the relative effectiveness of interventions is challenging. Several methodological options are now available. We aimed to determine the comparative validity of the adjusted indirect comparisons of RCTs with the mixed treatment comparison approach.

Methods

Using systematic searching, we identified all meta-analyses evaluating more than 3 interventions for a similar disease state with binary outcomes. We abstracted data on each clinical trial including population n and outcomes. We conducted fixed effects meta-analysis of each intervention versus mutual comparator and then applied the adjusted indirect comparison. We conducted a mixed treatment meta-analysis on all trials and compared the point estimates and 95% confidence/credible intervals (CIs/CrIs) to determine important differences.

Results

We included data from 7 reviews that met our inclusion criteria, allowing a total of 51 comparisons. According to the a priori consistency rule, we found 2 examples where the analytic comparisons were statistically significant using the mixed treatment comparison over the adjusted indirect comparisons and 1 example where this was vice versa. We found 6 examples where the direction of effect differed according to the indirect comparison method chosen and we found 9 examples where the confidence intervals were importantly different between approaches.

Conclusion

In most analyses, the adjusted indirect comparison yields estimates of relative effectiveness equal to the mixed treatment comparison. In less complex indirect comparisons, where all studies share a mutual comparator, both approaches yield similar benefits. As comparisons become more complex, the mixed treatment comparison may be favoured.
IL-21 and IL-10 have redundant roles but differential capacities at different stages of plasma cell generation from human germinal center B cells
Authors: Yoon Sun-Ok , Zhang Xin , Berner Paul , Choi Yong Sung
Published: September 2009

In the germinal center of lymphoid follicles, IL-10 is more effective in generating terminally differentiated CD138+ PC at the later stage of differentiation than IL-21.

The GC is the anatomical site where antigen-activated B cells differentiate into PC, producing high-affinity antibodies in physiological and pathological states. PC differentiation is regulated by multiple factors within the GC microenvironment, including cytokines. IL-21, a recently identified type I cytokine produced by GC-Th cells, promotes differentiation of human B cells into ISC. In this study, we investigated in detail the functional role of IL-21 in the course of GC-B cell differentiation into terminally differentiated PC compared with that of IL-10, a well-known PC differentiation factor. IL-21 had a greater capacity to initiate PC differentiation from CD77+ centroblasts than IL-10 by strongly inducing PC transcription factors through activation of STAT3; however, IL-10 was more potent than IL-21 in generating CD138+ PC from CD20–CD38++ plasmablasts in the terminal stage of GC-B cell differentiation. This differential effect of IL-21 and IL-10 was reflected in receptor expression on B cell subsets emerging in the course of differentiation. Our studies have revealed that IL-21 is a critical decision-maker for driving initial PC differentiation at the stage of CD77+ centroblasts, yet IL-10 is more effective in producing IgG by generating terminally differentiated CD138+ PC at the later stage of PC differentiation in the GC.
DSM–IV personality disorders in the WHO World Mental Health
Surveys
Authors: Huang Yueqin , Kotov Roman , de Girolamo Giovanni , Preti Antonio , Angermeyer Matthias , Benjet Corina , Demyttenaere Koen , de Graaf Ron , Gureje Oye , Karam Aimée Nasser , Lee Sing , Lépine Jean Pierre , Matschinger Herbert , Posada-Villa José , Suliman Sharain , Vilagut Gemma , Kessler Ronald C.
Published: September 2009

Background

Little is known about the cross-national population prevalence or
correlates of personality disorders.

Aims

To estimate prevalence and correlates of DSM–IV personality disorder
clusters in the World Health Organization World Mental Health (WMH)
Surveys.

Method

International Personality Disorder Examination (IPDE) screening questions
in 13 countries (n = 21 162) were calibrated to masked
IPDE clinical diagnoses. Prevalence and correlates were estimated using
multiple imputation.

Results

Prevalence estimates are 6.1% (s.e. = 0.3) for any personality disorder
and 3.6% (s.e. = 0.3), 1.5% (s.e. = 0.1) and 2.7% (s.e. = 0.2) for
Clusters A, B and C respectively. Personality disorders are significantly
elevated among males, the previously married (Cluster C), unemployed
(Cluster C), the young (Clusters A and B) and the poorly educated.
Personality disorders are highly comorbid with Axis I disorders.
Impairments associated with personality disorders are only partially
explained by comorbidity.

Conclusions

Personality disorders are relatively common disorders that often co-occur
with Axis I disorders and are associated with significant role
impairments beyond those due to comorbidity.
Minireview: Nuclear Receptor-Controlled Steroid Hormone Synthesis and Metabolism
Authors: He Jinhan , Cheng Qiuqiong , Xie Wen
Published: September 2009

Steroid hormones are essential in normal physiology whereas disruptions in hormonal homeostasis represent an important etiological factor for many human diseases. Steroid hormones exert most of their functions through the binding and activation of nuclear hormone receptors (NRs or NHRs), a superfamily of DNA-binding and often ligand-dependent transcription factors. In recent years, accumulating evidence has suggested that NRs can also regulate the biosynthesis and metabolism of steroid hormones. This review will focus on the recent progress in our understanding of the regulatory role of NRs in hormonal homeostasis and the implications of this regulation in physiology and diseases.
The Pequot Conspirator
Authors: White Ed
Published: September 2009

Historical interpretations of the Anglo-Pequot War have oscillated between ethnographic and conspiratorial explanations, arguing that it resulted either from cultural differences and misunderstandings or from scheming and provocation. But seventeenth-century accounts of the conflict demonstrate the interconnectedness of the ethnographic and conspiratorial frameworks, going as far as to suggest that the Pequots, one of the first Native American groups referred to by name, conspiratorially used their “Indianness” as a weapon. Tracing this connection, from the narratives of Philip Vincent and John Mason to those of John Underhill and Lion Gardiner, helps us better appreciate the racial origins of seventeenth-century conspiracy thought.
Mary Rowlandson's Hunger and the Historiography of Sexuality
Authors: Stein Jordan Alexander
Published: September 2009

Stein's essay argues that within the inquiry called “the history of sexuality,” a critical preoccupation with the materiality of bodies has occasioned some inattention to the experience and cultivation of sensations, which are clearly not reducible to somatic responses but which are just as clearly significant to the historical development of modern sexuality. Expanding the repertoire of sexuality to include the cultivation of sensations makes it possible to connect sexuality with other phenomena to which sexuality is generally considered to be unrelated. Representations of hunger in Mary Rowlandson's 1682 captivity narrative, The Sovereignty and Goodness of God, serve as the essay's principal case study. The essay argues that rethinking the history of sexuality in terms of the cultivation of sensations forces a reconsideration of the archives from which examples of pre- and early modern sexuality are drawn—a reconsideration that nominates aesthetic representations, rather than empirical evidence, as key sites of sexuality's modern articulation. The essay concludes that any concern for the manner in which the articulation of sensation produces human interiority would be a matter of “sexuality” under historical circumstances where genitals did not dominate understandings of that term.
Spirits of Emulation: Readers, Samplers, and the Republican Girl, 1787–1810
Authors: Howell William Huntting
Published: September 2009

Howell considers the arts of imitation and emulation as practiced by U.S. girls at the turn of the nineteenth century. He takes the best-selling novels and schoolbooks of Susanna Rowson as a starting point for reading a broad set of material-cultural artifacts, including embroideries, penmanship exercises, and recital performances. Although historians and literary critics have tended to deride such productions as “social accomplishments,”—as markers of a misogynist and antidemocratic ethos of “refinement”—this essay reads them as technologies of socialization. Aligning imitative and derivative aesthetics with sympathy and intersubjectivity, the essay argues that texts created by and for young women can offer critical insight into the twinned processes of individuation and deindividuation at the heart of “republican” theories of the subject. That is, it contends that “women's work” and the theories behind it afford not only an important purchase on preromantic genealogies of the self, but also more inclusive perspectives on the political history of the early United States.
Directionally convex ordering of random measures, shot noise fields, and some applications to wireless communications
Authors: Błaszczyszyn Bartłomiej , Yogeshwaran D.
Published: September 2009

Directionally convex ordering is a useful tool for comparing the dependence structure of random vectors, which also takes into account the variability of the marginal distributions. It can be extended to random fields by comparing all finite-dimensional distributions. Viewing locally finite measures as nonnegative fields of measure values indexed by the bounded Borel subsets of the space, in this paper we formulate and study directionally convex ordering of random measures on locally compact spaces. We show that the directionally convex order is preserved under some of the natural operations considered on random measures and point processes, such as deterministic displacement of points, independent superposition, and thinning, as well as independent, identically distributed marking. Further operations on Cox point processes such as position-dependent marking and displacement of points are shown to preserve the order. We also examine the impact of the directionally convex order on the second moment properties, in particular on clustering and on Palm distributions. Comparisons of Ripley's functions and pair correlation functions, as well as examples, seem to indicate that point processes higher in the directionally convex order cluster more. In our main result we show that nonnegative integral shot noise fields with respect to the directionally convex ordered random measures inherit this ordering from the measures. Numerous applications of this result are shown, in particular to comparison of various Cox processes and some performance measures of wireless networks, in both of which shot noise fields appear as key ingredients. We also mention a few pertinent open questions.
Maxima of moving sums in a Poisson random field
Authors: Chan Hock Peng
Published: September 2009

In this paper we examine the extremal tail probabilities of moving sums in a marked Poisson random field. These sums are computed by adding up the weighted occurrences of events lying within a scanning set of fixed shape and size. We also provide an alternative representation of the constants of the asymptotic formulae in terms of the occupation measure of the conditional local random field at zero, and extend these representations to the constants of asymptotic tail probabilities of Gaussian random fields.
The existence of quermass-interaction processes for nonlocally stable interaction and nonbounded convex grains
Authors: Dereudre David
Published: September 2009

We prove the existence of infinite-volume quermass-interaction processes in a general setting of nonlocally stable interaction and nonbounded convex grains. No condition on the parameters of the linear combination of the Minkowski functionals is assumed. The only condition is that the square of the random radius of the grain admits exponential moments for all orders. Our methods are based on entropy and large deviation tools.
Fcfs infinite bipartite matching of servers and customers
Authors: Caldentey René , Kaplan Edward H. , Weiss Gideon
Published: September 2009

We consider an infinite sequence of customers of typesand an infinite sequence of servers of typeswhere a server of typejcan serve a subset of customer typesC(j) and where a customer of typeican be served by a subset of server typesS(i). We assume that the types of customers and servers in the infinite sequences are random, independent, and identically distributed, and that customers and servers are matched according to their order in the sequence, on a first-come–first-served (FCFS) basis. We investigate this process of infinite bipartite matching. In particular, we are interested in the rateri,jthat customers of typeiare assigned to servers of typej. We present a countable state Markov chain to describe this process, and for some previously unsolved instances, we prove ergodicity and existence of limiting rates, and calculateri,j.