bluuebunny/crossref_metadata_2025 huggingface dataset:
Applying Diffusion of Innovation Theory to Intervention Development
Authors: Dearing James W.
Published: June 2009

Few social science theories have a history of conceptual and empirical study as long as does the diffusion of innovations. The robustness of this theory derives from the many disciplines and fields of study in which diffusion has been studied, from the international richness of these studies, and from the variety of new ideas, practices, programs, and technologies that have been the objects of diffusion research. Early theorizing from the beginning of the 20th century was gradually displaced by post hoc empirical research that described and explained diffusion processes. By the 1950s, diffusion researchers had begun to apply the collective knowledge learned about naturalistic diffusion in tests of process interventions to affect the spread of innovations. Now, this purposive objective has given form to a science of dissemination in which evidence-based practices are designed a priori not just to result in internal validity but to increase the likelihood that external validity and diffusion both are more likely to result. Here, I review diffusion theory and focus on seven concepts—intervention attributes, intervention clusters, demonstration projects, societal sectors, reinforcing contextual conditions, opinion leadership, and intervention adaptation—with potential for accelerating the spread of evidence-based practices, programs, and policies in the field of social work.
Parent Training With Behavioral Couples Therapy for Fathers' Alcohol Abuse
Authors: Lam Wendy K. K. , Fals-Stewart William , Kelley Michelle L.
Published: June 2009

This pilot study examined effects of Parent Skills with Behavioral Couples Therapy (PSBCT) on substance use, parenting, and relationship conflict among fathers with alcohol use disorders. Male participants ( N = 30) entering outpatient alcohol treatment, their female partners, and a custodial child (8 to 12 years) were randomly assigned to (a) PSBCT; (b) Behavioral Couples Therapy (BCT); or (c) Individual-Based Treatment (IBT). Children were not actively involved in treatment. Parents completed measures of substance use, couples' dyadic adjustment, partner violence, parenting, and Child Protection Services (CPS) involvement at pretreatment, posttreatment, 6- and 12-month follow-up. PSBCT was comparable to BCT on substance use, dyadic adjustment, and partner violence; both groups showed clinically meaningful effects over IBT. Compared to BCT, PSBCT resulted in larger effect sizes on parenting and CPS involvement throughout follow-up. PSBCT for fathers may enhance parenting couple- or individual-based treatment, and warrant examination in a larger, randomized efficacy trial.
Psychological Consequences of Sexual Victimization Resulting From Force, Incapacitation, or Verbal Coercion
Authors: Brown Amy L. , Testa Maria , Messman-Moore Terri L.
Published: June 2009

Recently, incapacitated rape has emerged as a distinct type of sexual victimization. However, little is known about its longer-term psychological consequences. Two studies compare the psychological consequences of incapacitated rape to those of forcible rape and verbal coercion. Generally, the traumatic impact of incapacitated rape was intermediate to that of verbal coercion and forcible rape; however, there were domains (e.g., current perceived trauma and emotional impact) in which incapacitated and forcible rape had a similar impact and other domains (e.g., attributions of responsibility) in which incapacitated rape was similar to verbal coercion. This research suggests that sexual assault researchers might benefit from separately examining forcible and incapacitated rape.
On a Special Class of Nonlinear Viscoelastic Solids
Authors: Pucci Edvige , Saccomandi Giuseppe
Published: June 2009

We investigate some possible nonlinear generalizations of the Kelvin—Voigt viscoelastic models. We use the usual idealization of creep and recovery experiments to discuss the mechanical significance of some constitutive requirements and we show that in the case of a shear-rate dependent viscosity localization of the solution is possible under a simple constitutive characterization.
Three-Dimensional Free Vibration Analysis of Cross-Ply Laminated Rectangular Plates with Free Edges Through a Displacement-Based Approach
Authors: Messina Arcangelo , Rollo Giosuè
Published: June 2009

This paper presents a model belonging to a theory that recently appeared in the literature dealing with accurate solutions of freely vibrating laminated plates. The present model, which is derived from a displacement-based variational approach, investigates both free edge boundary conditions and the possibility of obtaining accurate results without explicitly incorporating stress interlaminar continuity conditions where they are in principle requested. These investigations are carried out within the frame of multi-layered plates where the literature is lacking in relevant three-dimensional results.

In spite of the multi-layer nature of the plate, the model is developed as if the same plate were virtually made of a single layer because a suitable set of piecewise-smooth functions is used. Once the model is theoretically introduced, natural frequencies are evaluated for the case of plates with simply supported and free edge boundaries. The evaluations are compared with those few existing values of exact or approximate three-dimensional models, new results are provided for future comparisons and, finally, the performance of the model is tested with respect to extreme cases which could also deal with interesting engineering applications without reverting to non-immediate numerical schemes.
Energy Profiling and Analysis of the HPC Challenge Benchmarks
Authors: Shuaiwen Song  , Rong Ge  , Xizhou Feng  , Cameron Kirk W.
Published: June 2009

Future high performance systems must use energy efficiently to achieve petaFLOPS computational speeds and beyond. To address this challenge, we must first understand the power and energy characteristics of high performance computing applications. In this paper, we use a power-performance profiling framework called Power-Pack to study the power and energy profiles of the HPC Challenge benchmarks. We present detailed experimental results along with in-depth analysis of how each benchmark's workload characteristics affect power consumption and energy efficiency. This paper summarizes various findings using the HPC Challenge benchmarks, including but not limited to: 1) identifying application power profiles by function and component in a high performance cluster; 2) correlating applications' memory access patterns to power consumption for these benchmarks; and 3) exploring how energy consumption scales with system size and workload.
New Three-dimensional Matrix Models of the Ultrasonic Sandwich Transducers
Authors: Mančić Dragan D. , Stančić Goran Z.
Published: June 2009

The new 3D models of the prestressed symmetrical and unsymmetrical ultrasonic sandwich transducers are described in this article. The sandwich transducers are modeled through the application of a 3D matrix model of piezoceramic rings and discs, recently proposed by the authors. Theoretical analyses prove the proposed models as simple and easy to calculate, particularly suitable for the investigation of coupled vibrations cases. Experiments show that the measured resonance and antiresonance frequencies are in good agreement with the predicted results. Compared with traditional 1D models and methods, the results obtained by the proposed models matched better with the experimental results.
Flexural Properties of Nanoclay Syntactic Foam Sandwich Structures
Authors: Woldensenbet Eyassu , Sankella Narendra
Published: June 2009

Flexural properties of syntactic foam sandwich structures under three-point and four-point bending, and short beam shear tests are studied. Four different types of plain and nanoclay syntactic foam sandwich structures are fabricated and tested for flexural properties. The volume fraction of microballoons in the foam core is maintained at 60%, while 1% volume fraction of nanoclay is included in the nanoclay syntactic foam. The flexural properties of the nanoclay syntactic foam sandwich structures are compared with those of plain syntactic foam sandwich structures. Nanoclay incorporation hasimproved the flexural load bearing capacity of syntactic foam sandwich structures in three-point and four-point bending tests. However, the short beam shear test shows that nanoclay incorporation degrades the property of the sandwich structure. It is also found that the microballoons radius ratio effect on the strength of the sandwich structures is affected by the nanoclay.
Mechanical Behavior of Sandwich Structures using Natural Cork Agglomerates as Core Materials
Authors: Reis L. , Silva A.
Published: June 2009

Cork is a material of great value to the Portuguese economy. Unfortunately, its use is still restricted to traditional areas, with the agglomerate form in particular not being used to its full potential. The objective of this article is to analyze the viability of using cork-based material as core materials in sandwich structures in aeronautical and aerospace applications. The use of cork-based material is proposed because of its isolation properties (both thermal and acoustic) and there is no significant performance loss, when compared with the currently used materials. It presents other advantages, as well as, less wastage of energy in manufacturing and a better environmental integration, both in the transformation stage and in the end of life recycling stage. The objective of this work is to study the mechanical behavior of different sandwich specimens, with carbon/epoxy faces, and cores of different cork agglomerates and their comparison with the results obtained with similar specimens using current material cores. Experimental shear tests and three-point bending tests were carried out and the evolutions of the load— displacement curves of the different cork agglomerates/sandwiches were analyzed and discussed. The obtained results show that significant room for improvement still exists in use of cork-based core materials.
Review: Bariatric surgery: to treat diabesity
Authors: Flatt Peter R , Day Caroline , Bailey Clifford J
Published: June 2009

In obese patients bariatric surgery is increasing in popularity as a strategy to promote, and maintain, weight loss. In obese type 2 diabetes bypass, bariatric surgery improves glycaemic control — often to a greater extent than would be anticipated by weight loss alone. Surgical bypass procedures appear to initially offer a greater glucose-lowering effect than surgical restriction procedures. This review considers the rationale for bariatric surgery as a treatment for diabesity and the implications of the different procedures on the secretion and action of enteral hormones.
HbA1c - changing units
Authors: Day Caroline , Bailey Clifford J
Published: June 2009

Measurement of glycated haemoglobin A1C (HbA1C) provides an indication of longer-term glycaemic control. Standardisation of this test between laboratories is difficult to achieve, and most assays are currently calibrated to the values used in the Diabetes Control and Complications Trial (DCCT-aligned). With the availability of more specific reference standards it is now proposed that HbA1C is expressed as mmol HbA1C per mol of non-glycated haemoglobin. An HbA1C of 7% is approximately equal to 53 mmol/mol.
The Effectiveness of Using Communication-Centered Intervention to Facilitate Phonological Learning in Young Children
Authors: Hart Sharon , Gonzalez Lori
Published: June 2009

Treatment of preschool children with moderate to severe speech sound disorders is typically a long-term endeavor with many sounds and sound patterns requiring intervention. The purpose of this study was to determine if a communication-centered intervention would be effective in improving speech production with this population. The intervention consisted of the combined application of focused stimulation of key words during joint storybook reading and interactive practice of key words using communicative feedback. Participants displayed unique response patterns to the intervention. Two of the three participants demonstrated improvement in the use of the target speech pattern during intervention sessions, with one of the participants demonstrating generalization of the target pattern to conversational speech. Although the third participant did not demonstrate improvement during the intervention period, follow-up testing revealed some systemwide changes in his phonological system. This study provides preliminary support that communication-centered approaches are effective in facilitating phonological change.
myGRN: a database and visualisation system for the storage and analysis of developmental genetic regulatory networks
Authors: Bacha Jamil , Brodie James S , Loose Matthew W
Published: June 2009

Background

Biological processes are regulated by complex interactions between transcription factors and signalling molecules, collectively described as Genetic Regulatory Networks (GRNs). The characterisation of these networks to reveal regulatory mechanisms is a long-term goal of many laboratories. However compiling, visualising and interacting with such networks is non-trivial. Current tools and databases typically focus on GRNs within simple, single celled organisms. However, data is available within the literature describing regulatory interactions in multi-cellular organisms, although not in any systematic form. This is particularly true within the field of developmental biology, where regulatory interactions should also be tagged with information about the time and anatomical location of development in which they occur.

Description

We have developed myGRN (http://www.myGRN.org), a web application for storing and interrogating interaction data, with an emphasis on developmental processes. Users can submit interaction and gene expression data, either curated from published sources or derived from their own unpublished data. All interactions associated with publications are publicly visible, and unpublished interactions can only be shared between collaborating labs prior to publication. Users can group interactions into discrete networks based on specific biological processes. Various filters allow dynamic production of network diagrams based on a range of information including tissue location, developmental stage or basic topology. Individual networks can be viewed using myGRV, a tool focused on displaying developmental networks, or exported in a range of formats compatible with third party tools. Networks can also be analysed for the presence of common network motifs. We demonstrate the capabilities of myGRN using a network of zebrafish interactions integrated with expression data from the zebrafish database, ZFIN.

Conclusion

Here we are launching myGRN as a community-based repository for interaction networks, with a specific focus on developmental networks. We plan to extend its functionality, as well as use it to study networks involved in embryonic development in the future.
Generation and analysis of transcriptomic resources for a model system on the rise: the sea anemone Aiptasia pallida and its dinoflagellate endosymbiont
Authors: Sunagawa Shinichi , Wilson Emily C , Thaler Michael , Smith Marc L , Caruso Carlo , Pringle John R , Weis Virginia M , Medina Mónica , Schwarz Jodi A
Published: June 2009

Background

The most diverse marine ecosystems, coral reefs, depend upon a functional symbiosis between cnidarian hosts and unicellular dinoflagellate algae. The molecular mechanisms underlying the establishment, maintenance, and breakdown of the symbiotic partnership are, however, not well understood. Efforts to dissect these questions have been slow, as corals are notoriously difficult to work with. In order to expedite this field of research, we generated and analyzed a collection of expressed sequence tags (ESTs) from the sea anemone Aiptasia pallida and its dinoflagellate symbiont (Symbiodinium sp.), a system that is gaining popularity as a model to study cellular, molecular, and genomic questions related to cnidarian-dinoflagellate symbioses.

Results

A set of 4,925 unique sequences (UniSeqs) comprising 1,427 clusters of 2 or more ESTs (contigs) and 3,498 unclustered ESTs (singletons) was generated by analyzing 10,285 high-quality ESTs from a mixed host/symbiont cDNA library. Using a BLAST-based approach to predict which unique sequences derived from the host versus symbiont genomes, we found that the contribution of the symbiont genome to the transcriptome was surprisingly small (1.6–6.4%). This may reflect low levels of gene expression in the symbionts, low coverage of alveolate genes in the sequence databases, a small number of symbiont cells relative to the total cellular content of the anemones, or failure to adequately lyse symbiont cells. Furthermore, we were able to identify groups of genes that are known or likely to play a role in cnidarian-dinoflagellate symbioses, including oxidative stress pathways that emerged as a prominent biological feature of this transcriptome. All ESTs and UniSeqs along with annotation results and other tools have been made accessible through the implementation of a publicly accessible database named AiptasiaBase.

Conclusion

We have established the first large-scale transcriptomic resource for Aiptasia pallida and its dinoflagellate symbiont. These data provide researchers with tools to study questions related to cnidarian-dinoflagellate symbioses on a molecular, cellular, and genomic level. This groundwork represents a crucial step towards the establishment of a tractable model system that can be utilized to better understand cnidarian-dinoflagellate symbioses. With the advent of next-generation sequencing methods, the transcriptomic inventory of A. pallida and its symbiont, and thus the extent of AiptasiaBase, should expand dramatically in the near future.
Effect of voluntary running on adult hippocampal neurogenesis in cholinergic lesioned mice
Authors: Ho New Fei , Han Siew Ping , Dawe Gavin S
Published: June 2009

Background

Cholinergic neuronal dysfunction of the basal forebrain is observed in patients with Alzheimer's disease and dementia, and has been linked to decreased neurogenesis in the hippocampus, a region involved in learning and memory. Running is a robust inducer of adult hippocampal neurogenesis. This study aims to address the effect of running on hippocampal neurogenesis in lesioned mice, where septohippocampal cholinergic neurones have been selectively eliminated in the medial septum and diagonal band of Broca of the basal forebrain by infusion of mu-p75-saporin immunotoxin.

Results

Running increased the number of newborn cells in the dentate gyrus of the hippocampus in cholinergic denervated mice compared to non-lesioned mice 24 hours after injection of bromodeoxyuridine (BrdU). Although similar levels of surviving cells were present in cholinergic depleted animals and their respective controls four weeks after injection of BrdU, the majority of progenitors that proliferate in response to the initial period of running were not able to survive beyond one month without cholinergic input. Despite this, the running-induced increase in the number of surviving neurones was not affected by cholinergic depletion.

Conclusion

The lesion paradigm used here models aspects of the cholinergic deficits associated with Alzheimer's Disease and aging. We showed that running still increased the number of newborn cells in the adult hippocampal dentate gyrus in this model of neurodegenerative disease.
The clinicopathologic observation, c-KIT gene mutation and clonal status of gastrointestinal stromal tumor in the sacrum
Authors: Gong Li , Li Yan-Hong , Zhao Hua-Dong , Zhao Jian-Ye , Zhang Wei
Published: June 2009

Background

It is very rare that gastrointestinal stromal tumor (GIST) occurs in the sacrum. Only one case of GIST occuring in the sacral region, with intracranial metastasis, has been reported in the literature. Moreover, only few cases have been published in literature about its clonal origin.

Case presentation

In this report, we present a rare case of GIST occuring in the sacrum and describe its clinicopathologic features, c-KIT gene mutation and clonal status. Microscopically, the lesion was composed of spindle cells arranged in cords, knitted and whirlpool patterns. Trabecula of bone were found in the lesion. The cytoplasm of tumor cells were abundant, and the nuclei were fusiform. Mitotic figures were rare. Immunohistochemically, the tumor cells showed positive reactivity for CD117 and CD34. On mutation analysis, a c-KIT gene mutation was found in exon 11. The result of clonal analysis demonstrated that the GIST was monoclonal.

Conclusion

In summary, we showed that tumor material, phenotypically identical with GISTs was found in the sacrum. It is difficult to differentiate GISTs from other spindle cell tumors, hence the need for immunohistochemistry, the examination of c-KIT gene amplification and sequencing.
A human glomerular SAGE transcriptome database
Authors: Nyström Jenny , Fierlbeck Wolfgang , Granqvist Anna , Kulak Stephen C , Ballermann Barbara J
Published: June 2009

Background

To facilitate in the identification of gene products important in regulating renal glomerular structure and function, we have produced an annotated transcriptome database for normal human glomeruli using the SAGE approach.

Description

The database contains 22,907 unique SAGE tag sequences, with a total tag count of 48,905. For each SAGE tag, the ratio of its frequency in glomeruli relative to that in 115 non-glomerular tissues or cells, a measure of transcript enrichment in glomeruli, was calculated. A total of 133 SAGE tags representing well-characterized transcripts were enriched 10-fold or more in glomeruli compared to other tissues. Comparison of data from this study with a previous human glomerular Sau3A-anchored SAGE library reveals that 47 of the highly enriched transcripts are common to both libraries. Among these are the SAGE tags representing many podocyte-predominant transcripts like WT-1, podocin and synaptopodin. Enrichment of podocyte transcript tags SAGE library indicates that other SAGE tags observed at much higher frequencies in this glomerular compared to non-glomerular SAGE libraries are likely to be glomerulus-predominant. A higher level of mRNA expression for 19 transcripts represented by glomerulus-enriched SAGE tags was verified by RT-PCR comparing glomeruli to lung, liver and spleen.

Conclusion

The database can be retrieved from, or interrogated online at http://cgap.nci.nih.gov/SAGE. The annotated database is also provided as an additional file with gene identification for 9,022, and matches to the human genome or transcript homologs in other species for 1,433 tags. It should be a useful tool for in silico mining of glomerular gene expression.
Cognitive behavioral therapy and physical exercise for climacteric symptoms in breast cancer patients experiencing treatment-induced menopause: design of a multicenter trial
Authors: Duijts Saskia FA , Oldenburg Hester SA , van Beurden Marc , Aaronson Neil K
Published: June 2009

Background

Premature menopause is a major concern of younger women undergoing adjuvant therapy for breast cancer. Hormone replacement therapy is contraindicated in women with a history of breast cancer. Non-hormonal medications show a range of bothersome side-effects. There is growing evidence that cognitive behavioral therapy (CBT) and physical exercise can have a positive impact on symptoms in naturally occurring menopause. The objective of this study is to investigate the efficacy of these interventions among women with breast cancer experiencing treatment-induced menopause.

Methods/design

In a randomized, controlled, multicenter trial, we are evaluating the effectiveness of CBT/relaxation, of physical exercise and of these two program elements combined, in reducing menopausal symptoms, improving sexual functioning, reducing emotional distress, and in improving the health-related quality of life of younger breast cancer patients who experience treatment-induced menopause. 325 breast cancer patients (aged < 50) are being recruited from hospitals in the Amsterdam region, and randomly allocated to one of the three treatment groups or a 'waiting list' control group. Self-administered questionnaires are completed by the patients at baseline, and at 12 weeks (T1) and 6 months (T2) post-study entry. Upon completion of the study, women assigned to the control group will be given the choice of undergoing either the CBT or physical exercise program.

Discussion

Cognitive behavioral therapy and physical exercise are potentially useful treatments among women with breast cancer undergoing treatment-induced, premature menopause. For these patients, hormonal and non-hormonal therapies are contraindicated or have a range of bothersome side-effects. Hence, research into these interventions is needed, before dissemination and implementation in the current health care system can take place.

Trial registration

The study is registered at the Netherlands Trial Register (NTR1165) and ClinicalTrials.gov (NCT00582244).
A cross-country review of strategies of the German development cooperation to strengthen human resources
Authors: Windisch Ricarda , Wyss Kaspar , Prytherch Helen
Published: June 2009

Background

Recent years have seen growing awareness of the importance of human resources for health in health systems and with it an intensifying of the international and national policies in place to steer a response. This paper looks at how governments and donors in five countries – Cameroon, Indonesia, Malawi, Rwanda and Tanzania – have translated such policies into action. More detailed information with regard to initiatives of German development cooperation brings additional depth to the range and entry doors of human resources for health initiatives from the perspective of donor cooperation.

Methods

This qualitative study systematically presents different approaches and stages to human resources for health development in a cross-country comparison. An important reference to capture implementation at country level was grey literature such as policy documents and programme reports. In-depth interviews along a predefined grid with national and international stakeholders in the five countries provided information on issues related to human resources for health policy processes and implementation.

Results

All five countries have institutional entities in place and have drawn up national policies to address human resources for health. Only some of the countries have translated policies into strategies with defined targets and national programmes with budgets and operational plans. Traditional approaches of supporting training for individual health professionals continue to dominate. In some cases partners have played an advocacy and technical role to promote human resources for health development at the highest political levels, but usually they still focus on the provision of ad hoc training within their programmes, which may not be in line with national human resources for health development efforts or may even be counterproductive to them. Countries that face an emergency, such as Malawi, have intensified their efforts within a relatively short time and by using donor funding support also through new initiatives such as the Global Fund to Fight AIDS, Tuberculosis and Malaria.

Conclusion

The country case studies illustrate the range of initiatives that have surged in recent years and some main trends in terms of donor initiatives. Though attention and priority attributed to human resources for health is increasing, there is still a focus on single initiatives and programmes. This can be explained in part by the complexity of the issue, and in part by its need to be addressed through a long-term approach including public sector and salary reforms that go beyond the health sector.
Assessment of methods for prediction of human West Nile virus (WNV) disease from WNV-infected dead birds
Authors: Veksler Anna , Eidson Millicent , Zurbenko Igor
Published: June 2009

Background

West Nile virus (WNV) is currently the leading cause of arboviral-associated encephalitis in the U.S., and can lead to long-term neurologic sequelae. Improvements in dead bird specimen processing time, including the availability of rapid field laboratory tests, allows reassessment of the effectiveness of using WNV-positive birds in forecasting human WNV disease.

Methods

Using New York State integrated WNV surveillance data from transmissions seasons in 2001–2003, this study determined which factors associated with WNV-positive dead birds are most closely associated with human disease. The study also addressed the 'delay' period between the distribution of the dead bird variable and the distribution of the human cases. In the last step, the study assessed the relative risk of contracting WNV disease for people who lived in counties with a 'signal' value of the predictor variable versus people who lived in counties with no 'signal' value of the predictor variable.

Results

The variable based on WNV-positive dead birds [(Positive/Tested)*(Population/Area)] was identified as the optimum variable for predicting WNV human disease at a county level. The delay period between distribution of the variable and human cases was determined to be approximately two weeks. For all 3 years combined, the risk of becoming a WNV case for people who lived in 'exposed' counties (those with levels of the positive dead bird variable above the signal value) was about 2 times higher than the risk for people who lived in 'unexposed' counties, but risk varied by year.

Conclusion

This analysis develops a new variable based on WNV-positive dead birds, [(Positive/Tested)*(Population/Area)] to be assessed in future real-time studies for forecasting the number of human cases in a county. A delay period of approximately two weeks between increases in this variable and the human case onset was identified. Several threshold 'signal' values were assessed and found effective at indicating human case risk, although specific thresholds are likely to vary by region and surveillance system differences.
Normal ventral telencephalic expression of Pax6 is required for normal development of thalamocortical axons in embryonic mice
Authors: Simpson T Ian , Pratt Thomas , Mason John O , Price David J
Published: June 2009

Background

In addition to its well-known expression in dorsal telencephalic progenitor cells, where it regulates cell proliferation and identity, the transcription factor Pax6 is expressed in some ventral telencephalic cells, including many postmitotic neurons. Its functions in these cells are unknown.

Results

We generated a new floxed allele of Pax6 and tested the consequences of a highly specific ventral telencephalic depletion of Pax6. We used the Six3
A1A2
-Cre allele that drives production of Cre recombinase in a specific region of Pax6-expression close to the internal capsule, through which thalamic axons navigate to cerebral cortex. Depletion in this region caused many thalamic axons to take aberrant routes, either failing to turn normally into ventral telencephalon to form the internal capsule or exiting the developing internal capsule ventrally. We tested whether these defects might have resulted from abnormalities of two structural features proposed to guide thalamic axons into and through the developing internal capsule. First, we looked for the early pioneer axons that project from the region of the future internal capsule to the thalamus and are thought to guide thalamocortical axons to the internal capsule: we found that they are present in conditional mutants. Second, we examined the development of the corridor of Islet1-expressing cells that guides thalamic axons through ventral telencephalon and found that it was broader and less dense than normal in conditional mutants. We also examined corticofugal axons that are thought to interact with ascending thalamocortical axons, resulting in each set providing guidance to the other, and found that some are misrouted to lateral telencephalon.

Conclusion

These findings indicate that ventral telencephalic Pax6 is important for formation of the Islet1-expressing corridor and the thalamic and cortical axons that grow through it. We suggest that Pax6 might affect thalamic axonal growth indirectly via its effect on the corridor.
Oxidative modifications, mitochondrial dysfunction, and impaired protein degradation in Parkinson's disease: how neurons are lost in the Bermuda triangle
Authors: Malkus Kristen A , Tsika Elpida , Ischiropoulos Harry
Published: June 2009

While numerous hypotheses have been proposed to explain the molecular mechanisms underlying the pathogenesis of neurodegenerative diseases, the theory of oxidative stress has received considerable support. Although many correlations have been established and encouraging evidence has been obtained, conclusive proof of causation for the oxidative stress hypothesis is lacking and potential cures have not emerged. Therefore it is likely that other factors, possibly in coordination with oxidative stress, contribute to neuron death. Using Parkinson's disease (PD) as the paradigm, this review explores the hypothesis that oxidative modifications, mitochondrial functional disruption, and impairment of protein degradation constitute three interrelated molecular pathways that execute neuron death. These intertwined events are the consequence of environmental exposure, genetic factors, and endogenous risks and constitute a "Bermuda triangle" that may be considered the underlying cause of neurodegenerative pathogenesis.
Alterations in peripheral blood memory B cells in patients with active rheumatoid arthritis are dependent on the action of tumour necrosis factor
Authors: Souto-Carneiro M Margarida , Mahadevan Vijayabhanu , Takada Kazuki , Fritsch-Stork Ruth , Nanki Toshihiro , Brown Margaret , Fleisher Thomas A , Wilson Mildred , Goldbach-Mansky Raphaela , Lipsky Peter E
Published: June 2009

Introduction

Disturbances in peripheral blood memory B cell subpopulations have been observed in various autoimmune diseases, but have not been fully delineated in rheumatoid arthritis (RA). Additionally, the possible role of tumour necrosis factor (TNF) in regulating changes in specific peripheral blood memory B cell subsets in RA is still unclear.

Methods

The frequency and distribution of B cell subsets in the peripheral blood and synovial membrane of active RA patients with long-standing disease have been analysed. Additionally, the possible role of TNF in causing disturbances in memory B cell subsets in RA patients was assessed in a clinical trial with the specific TNF-neutralising antibody, infliximab.

Results

RA patients, independent of disease duration, have a significantly lower frequency of peripheral blood pre-switch IgD+CD27+ memory B cells than healthy individuals, whereas post-switch IgD-CD27+ accumulate with increased disease duration. Notably, both pre-switch IgD+CD27+ and post-switch IgD-CD27+ memory B cells accumulate in the synovial membrane of RA patients. Finally, anti-TNF therapy increased the frequency of pre-switch IgD+CD27 memory B cells in the peripheral blood.

Conclusions

The data suggest that decreases in peripheral blood IgD+CD27+ pre-switch memory B cells in RA reflect their accumulation in the synovial tissue. Moreover, the significant increase in the peripheral blood pre-switch memory B cells in patients who underwent specific TNF-blockade with infliximab indicates that trafficking of memory B cells into inflamed tissue in RA patients is regulated by TNF and can be corrected by neutralising TNF.
Mesenchymal progenitor cell markers in human articular cartilage: normal distribution and changes in osteoarthritis
Authors: Grogan Shawn P , Miyaki Shigeru , Asahara Hiroshi , D'Lima Darryl D , Lotz Martin K
Published: June 2009

Introduction

Recent findings suggest that articular cartilage contains mesenchymal progenitor cells. The aim of this study was to examine the distribution of stem cell markers (Notch-1, Stro-1 and VCAM-1) and of molecules that modulate progenitor differentiation (Notch-1 and Sox9) in normal adult human articular cartilage and in osteoarthritis (OA) cartilage.

Methods

Expression of the markers was analyzed by immunohistochemistry (IHC) and flow cytometry. Hoechst 33342 dye was used to identify and sort the cartilage side population (SP). Multilineage differentiation assays including chondrogenesis, osteogenesis and adipogenesis were performed on SP and non-SP (NSP) cells.

Results

A surprisingly high number (>45%) of cells were positive for Notch-1, Stro-1 and VCAM-1 throughout normal cartilage. Expression of these markers was higher in the superficial zone (SZ) of normal cartilage as compared to the middle zone (MZ) and deep zone (DZ). Non-fibrillated OA cartilage SZ showed reduced Notch-1 and Sox9 staining frequency, while Notch-1, Stro-1 and VCAM-1 positive cells were increased in the MZ. Most cells in OA clusters were positive for each molecule tested. The frequency of SP cells in cartilage was 0.14 ± 0.05% and no difference was found between normal and OA. SP cells displayed chondrogenic and osteogenic but not adipogenic differentiation potential.

Conclusions

These results show a surprisingly high number of cells that express putative progenitor cell markers in human cartilage. In contrast, the percentage of SP cells is much lower and within the range of expected stem cell frequency. Thus, markers such as Notch-1, Stro-1 or VCAM-1 may not be useful to identify progenitors in cartilage. Instead, their increased expression in OA cartilage implicates involvement in the abnormal cell activation and differentiation process characteristic of OA.
Off hour admission to an intensivist-led ICU is not associated with increased mortality
Authors: Meynaar Iwan A , van der Spoel Johan I , Rommes Johannes H , van Spreuwel-Verheijen Margot , Bosman Rob J , Spronk Peter E
Published: June 2009

Introduction

Caring for the critically ill is a 24-hour-a-day responsibility, but not all resources and staff are available during off hours. We evaluated whether intensive care unit (ICU) admission during off hours affects hospital mortality.

Methods

This retrospective multicentre cohort study was carried out in three non-academic teaching hospitals in the Netherlands. All consecutive patients admitted to the three ICUs between 2004 and 2007 were included in the study, except for patients who did not fulfil APACHE II criteria (readmissions, burns, cardiac surgery, younger than 16 years, length of stay less than 8 hours). Data were collected prospectively in the ICU databases. Hospital mortality was the primary endpoint of the study. Off hours was defined as the interval between 10 pm and 8 am during weekdays and between 6 pm and 9 am during weekends. Intensivists, with no responsibilities outside the ICU, were present in the ICU during daytime and available for either consultation or assistance on site during off hours. Residents were available 24 hours a day 7 days a week in two and fellows in one of the ICUs.

Results

A total of 6725 patients were included in the study, 4553 (67.7%) admitted during daytime and 2172 (32.3%) admitted during off hours. Baseline characteristics of patients admitted during daytime were significantly different from those of patients admitted during off hours. Hospital mortality was 767 (16.8%) in patients admitted during daytime and 469 (21.6%) in patients admitted during off hours (P < 0.001, unadjusted odds ratio 1.36, 95%CI 1.20–1.55). Standardized mortality ratios were similar for patients admitted during off hours and patients admitted during daytime. In a logistic regression model APACHE II expected mortality, age and admission type were all significant confounders but off-hours admission was not significantly associated with a higher mortality (P = 0.121, adjusted odds ratio 1.125, 95%CI 0.969–1.306).

Conclusions

The increased mortality after ICU admission during off hours is explained by a higher illness severity in patients admitted during off hours.
Finite-difference modeling of wave propagation and diffusion in poroelastic media
Authors: Wenzlau Fabian , Müller Tobias M.
Published: June 2009

Numerical modeling of seismic waves in heterogeneous, porous reservoir rocks is an important tool for interpreting seismic surveys in reservoir engineering. Various theoretical studies derive effective elastic moduli and seismic attributes from complex rock properties, involving patchy saturation and fractured media. To confirm and further develop rock-physics theories for reservoir rocks, accurate numerical modeling tools are required. Our 2D velocity-stress, finite-difference scheme simulates waves within poroelastic media as described by Biot’s theory. The scheme is second order in time, contains high-order spatial derivative operators, and is parallelized using the domain-decomposition technique. A series of numerical experiments that are compared to exact analytical solutions allow us to assess the stability conditions and dispersion relations of the explicit poroelastic finite-differ-ence method. The focus of the experiments is to model wave-induced flow accurately in the vicinity of mesoscopic heterogeneities such as cracks and gas inclusions in partially saturated rocks. For that purpose, a suitable numerical setup is applied to extract seismic attenuation and dispersion from quasi-static experiments. Our results confirm that finite-difference modeling is a valuable tool to simulate wave propa-gation in heterogeneous poroelastic media, provided the temporal and spatial scales of the propagating waves and of the induced fluid-diffusion processes are resolved properly.
Iterative deconvolution and semiblind deconvolution methods in magnetic archaeological prospecting
Authors: Zunino Andrea , Benvenuto Federico , Armadillo Egidio , Bertero Mario , Bozzo Emanuele
Published: June 2009

In archaeological magnetic prospecting, most targets can be modeled by a single layer of constant burial depth and thickness. With this assumption, recovery of the magnetization distribution of the buried layer from magnetic surface measurements is a 2D deconvolution problem. Because this problem is ill posed, it requires regularization techniques to be solved. In analogy with image reconstruction, the solution showing the resolved subsoil features can be considered a focused version of the blurred and noisy magnetic image. Exploiting image deconvolution tools, two iterative reconstruction methods are applied to minimize the least-squares functional: the standard projected Landweber method and a proposed modification of the iterative space reconstruction algorithm. Different regularization functionals inject a priori information in the optimization problem, and the split-gradient method modifies the algorithms. Numerical simulations in the case of perfect knowledge of the impulse response functions demonstrate that the edge-preserving, total-variation functionals give the best results. An iterative semiblind deconvolution method to estimate the burial depth of the source layer was used with a real data set to test the effectiveness of the method.
Application of the multi-vari method in identification of the problem assignable cause set of variation
Authors: Devedžić G , Mirić N
Published: June 2009

Any working process is designed with the intent to create an output that will satisfy either predetermined requirement or a potential customer. One of the parameters that will influence customer satisfaction is the variation of the working process output that is within or outside the originally predetermined or expected range of variation. The meaning of ‘expected range of variation’ in this context is related to a relatively recently recognized dimension of quality ‘perceived quality’, whereas a ‘predetermined range of variation’ is a synonym for Crosby's quality definition of conformance to requirements and specifications (Crosby, Quality is free: The art of making quality certain, 1979, McGraw-Hill). The working process output is controlled by variables that are functions of time and/or working environment specifics. A change of variables may create an ‘uncontrolled’ output that shows a level of variation outside the predetermined or expected requirements. From a management prospective this is called either a problem or an opportunity.

The ‘uncontrolled’ outputs have a negative impact on the performance of the working environment, which is, in most cases, closely related to the production cost. The unknown assignable cause of variation (or root cause of variation) that is contained within the unknown critical set of variation (or family of variation) is the main reason for the uncontrolled outputs. In view of the cost as a function of time, in any working environment, it is important to identify quickly the critical set of variation which would lead to a quicker problem solution and better control of the financial figures.

Multi-vari is a statistical engineering method used to analyse a set of data acquired in an organized manner and analysed graphically or analytically. There are two basic applications of this method: (i) to determine statistically the homogeneity of the data distribution and (ii) to identify the critical set of variation that contains the assignable cause of the variation. This paper focuses on the second application of this method, which gives the greatest return on investment with respect to day-to-day operations in different working environments. The multi-vari method presented and application examples should help readers to understand the essential features, to evaluate the method, and to identify its potential for application in their areas of expertise.
Third-order non-local beam theories for the analysis of symmetrical nanobeams
Authors: Niu J C , Lim C W , Leung A Y T
Published: June 2009

This article presents formulation of third-order non-local beam theories based on Eringen's non-local continuum theory and the Reddy and Leung higher-order beam models for bending, buckling, and vibration of nanobeams. By applying the variational principle, an asymptotic governing differential equation of infinite-order strain gradients is derived and subsequently the governing equation of motion of the nanobeams is obtained. For practical applications, the Navier solutions of the asymptotic non-local model are presented and discussed. Bending, buckling, and vibration of nanobeams with simply supported boundary conditions are investigated. Numerical examples are presented to illustrate the corresponding effects of non-local scale parameter, rotary inertia and transverse shear deformation on deflections, buckling loads, and natural frequencies of nanobeams.
Influence of filler material on micro- and macro-mechanical behaviour of laser-beam-welded T-joint for aerospace applications
Authors: Squillace A , Prisco U
Published: June 2009

3.2mm thick laminated skins of AA7475 alloy and 2.5mm thick extruded stringers of the alloy PA765 were T-jointed by laser beam welding. Two different joints were fabricated using identical welding parameters but two different alloys as welding wires, AA5356 and AA4047. The microstructure, the tensile, and the failure behaviours of the two welded joints are studied by means of optical and electronic microscope, micro-indentation, and tensile testing. Weld beads extension using AA5356 are larger than those using AA4047. Microstructure of the welded joints is quite similar: at the centre of the fusion zone, cellular dendrites are present; near the fusion line in the fusion region, a chill zone and parallel dendrite arms are found; and an evident heat-affected zone is observed between the fusion line and the parent material. Microhardness tests reveal that the partially melted zone is a weak band in the welded specimens. Indeed, for both joints, failure took place at the partially melted zone upon tensile loading. Hoop testing demonstrates that AA4047 joints present a lower yield stress than AA5356 joints although both joints show similar tensile strength and elongation at break. AA4047 joints show more strength than AA5356 joints upon T-pull testing.