201 research outputs found
Improving collaboration between primary care research networks using Access Grid technology
Access Grid (AG) is an Internet2-driven, high performance audio_visual conferencing technology used worldwide by academic and government organisations to enhance communication, human interaction and group collaboration. AG technology is particularly promising for improving academic multi-centre research collaborations. This manuscript describes how the AG technology was utilised by the electronic Primary Care Research Network (ePCRN) that is part of the National Institutes of Health (NIH) Roadmap initiative to improve primary care research and collaboration among practice- based research networks (PBRNs) in the USA. It discusses the design, installation and use of AG implementations, potential future applications, barriers to adoption, and suggested solutions
Hip contact forces in asymptomatic total hip replacement patients differ from normal healthy individuals: implications for preclinical testing
BACKGROUND
Preclinical durability testing of hip replacement implants is standardised by ISO-14242-1 (2002) which is based on historical inverse dynamics analysis using data obtained from a small sample of normal healthy individuals. It has not been established whether loading cycles derived from normal healthy individuals are representative of loading cycles occurring in patients following total hip replacement.
METHODS
Hip joint kinematics and hip contact forces derived from multibody modelling of forces during normal walking were obtained for 15 asymptomatic total hip replacement patients and compared to 38 normal healthy individuals and to the ISO standard for pre-clinical testing.
FINDINGS
Hip kinematics in the total hip replacement patients were comparable to the ISO data and the hip contact force in the normal healthy group was also comparable to the ISO cycles. Hip contact forces derived from the asymptomatic total hip replacement patients were comparable for the first part of the stance period but exhibited 30% lower peak loads at toe-off.
INTERPRETATION
Although the ISO standard provides a representative kinematic cycle, the findings call into question whether the hip joint contact forces in the ISO standard are representative of those occurring in the joint following total hip replacement
On the effects of the fix geometric constraint in 2D profiles on the reusability of parametric 3D CAD models
[EN] In order to be reusable, history-based feature-based parametric CAD models must reliably allow for modifications while maintaining their original design intent. In this paper, we demonstrate that relations that fix the location of geometric entities relative to the reference system produce inflexible profiles that reduce model reusability. We present the results of an experiment where novice students and expert CAD users performed a series of modifications in different versions of the same 2D profile, each defined with an increasingly higher number of fix geometric constraints. Results show that the amount of fix constraints in a 2D profile correlates with the time required to complete reusability tasks, i.e., the higher the number of fix constraints in a 2D profile, the less flexible and adaptable the profile becomes to changes. In addition, a pilot software tool to automatically track this type of constraints was developed and tested. Results suggest that the detection of fix constraint overuse may result in a new metric to assess poor quality models with low reusability. The tool provides immediate feedback for preventing high semantic level quality errors, and assistance to CAD users. Finally, suggestions are introduced on how to convert fix constraints in 2D profiles into a negative metric of 3D model quality.The authors would like to thank Raquel Plumed for her support in the statistical analysis. This work has been partially funded by Grant UJI-A02017-15 (Universitat Jaume I) and DPI201784526-R (MINECO/AEI/FEDER, UE), project CAL-MBE. The authors also wish to thank the editor and reviewers for their valuable comments and suggestions that helped us improve the quality of the paper.González-Lluch, C.; Company, P.; Contero, M.; Pérez Lopez, DC.; Camba, JD. (2019). On the effects of the fix geometric constraint in 2D profiles on the reusability of parametric 3D CAD models. 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What is housing affordability? The case for the residual income approach
This article seeks to increase the awareness of and support for the residual income approach to housing affordability indicators and standards, especially in the United States. It begins with an overview of various semantic, substantive, and definitional issues relating to the notion of affordability, leading to an argument supporting the conceptual soundness of the residual income approach. The concept is then briefly set into the historical context of U.S. and British debates on affordability measures. This description is followed by a discussion of two of the principal issues involved in crafting an operational residual income standard: the selection of a normative standard for non-housing items and the treatment of taxes. The article concludes by considering some of the potential implications of the residual income paradigm for the analysis of housing problems and needs, for housing subsidy policy, and for mortgage underwriting practice
Evaluation of CD46 re-targeted adenoviral vectors for clinical ovarian cancer intraperitoneal therapy
Ovarian cancer accounts for >140 000 deaths globally each year. Typically, disease is asymptomatic until an advanced, incurable stage. Although response to cytotoxic chemotherapy is frequently observed, resistance to conventional platinum-based therapies develop rapidly. Improved treatments are therefore urgently required. Virotherapy offers great potential for ovarian cancer, where the application of local, intraperitoneal delivery circumvents some of the limitations of intravenous strategies. To develop effective, adenovirus (Ad)-based platforms for ovarian cancer, we profiled the fluid and cellular components of patient ascites for factors known to influence adenoviral transduction. Levels of factor X (FX) and neutralizing antibodies (nAbs) in ascitic fluid were quantified and tumor cells were assessed for the expression of coxsackie virus and adenovirus receptor (CAR) and CD46. We show that clinical ascites contains significant levels of FX but consistently high CD46 expression. We therefore evaluated in vitro the relative transduction of epithelial ovarian cancers (EOCs) by Ad5 (via CAR) and Ad5 pseudotyped with the fiber of Ad35 (Ad5T*F35++) via CD46. Ad5T*F35++ achieved significantly increased transduction in comparison to Ad5 (P<0.001), independent of FX and nAb levels. We therefore propose selective transduction of CD46 over-expressing EOCs using re-targeted, Ad35-pseudotyped Ad vectors may represent a promising virotherapy for ovarian cance
On the pulmonary toxicity of oxygen. 4. The thyroid arena
Author Posting. © The Author(s), 2011. This is the author's version of the work. It is posted here by permission of Elsevier B.V. for personal use, not for redistribution. The definitive version was published in Experimental and Molecular Pathology 92 (2012): 140-154, doi:10.1016/j.yexmp.2011.11.006.Normally developed thyroid function is critical to the transition from fetal to neonatal life with the
onset of independent thermoregulation, the most conspicuous of the many ways in which thyroid
secretions act throughout the body. A role for thyroid secretions in growth and maturation of the
lungs as part of the preparation for the onset of breathing has been recognized for some time but how
this contributes to tissue and cell processes and defenses under the duress of respiratory distress has
not been well examined. Extensive archival autopsy material was searched for thyroid and adrenal
weights, first by gestational age, and then for changes during the first hours after birth as ratios to
body weight. After a gestational age of 22 weeks the fetal thyroid and adrenal glands at autopsy in
those with hyaline membrane disease are persistently half the size of those in "normal" infants dying
with other disorders. When the thyroid is examined shortly after birth it reveals a post natal loss of
mass per body weight of similar orders of magnitude which does not occur in the control group. A
clinical sample of premature infants with (12) and without (14) hyaline membrane disease was
tested for T4, TSH, TBG, and total serum protein. The results also demonstrate a special subset with
lower birth weights at the same gestational age, and lower serum T4 and total serum protein. Ventilatory distress in newborn rabbits was induced by bilateral cervical vagotomy at 24 hours post
natal following earlier injection of thyroxine (T4) or thyroid stimulating hormone (TSH) and
comparisons were made with untreated animals and by dose. Early life thyroidectomy was
performed followed by exposure to either air or 100% oxygen. A final experiment in air was
vagotomy after thyroidectomy. Composite analysis of these methods indicates that thyroid factors
are both operative and important in the newborn animal with ventilatory distress. This work and
the archival data indicate those infants destined to develop hyaline membrane disease through
respiratory distress are a distinct developmental and clinical subset with the point of departure from
otherwise normal development and maturation in the second or early third trimester. This interval
is known to be a period of marked variation in the overview indicators of fetal progress through
gestational time. The initiating factor or circumstance which then separates this special subset from
normal future development is placed by these observations firmly into the period when human fetal
TSH dramatically rises 7-fold (17.5-25.5 weeks) followed by a lesser 3 to 4 fold increase in T4
which is extended into the early third trimester. The earlier part of this interval is characterized by
the thyrotrophic action of chorionic gonadotropin (hCG). The possibility that abnormalities in the
intrauterine environment secondary to maternal infection play a role within this time frame is
indicated by the demonstration that interleukin-2 (IL-2) induces an anterior pituitary release of
TSH. Since IL-2 has this property and is not an acute phase cytokine, some form of chronic
infection or an immunopathic process seems more likely as a possible active factor in pathogenesis.The work in this report was performed under a grant to the University of Chicago from the John A.
Hartford Foundation
The Long Exception: Rethinking the Place of the New Deal in American History
The Long Exception examines the period from Franklin Roosevelt to the end of the twentieth century and argues that the New Deal was more of an historical aberration—a byproduct of the massive crisis of the Great Depression—than the linear triumph of the welfare state. The depth of the Depression undoubtedly forced the realignment of American politics and class relations for decades, but, it is argued, there is more continuity in American politics between the periods before the New Deal order and those after its decline than there is between the postwar era and the rest of American history. Indeed, by the early seventies the arc of American history had fallen back upon itself. While liberals of the seventies and eighties waited for a return to what they regarded as the normality of the New Deal order, they were actually living in the final days of what Paul Krugman later called the interregnum between Gilded Ages. The article examines four central themes in building this argument: race, religion, class, and individualism
Bose-Einstein Condensation in Magnetic Insulators
The elementary excitations in antiferromagnets are magnons, quasiparticles
with integer spin and Bose statistics. In an experiment their density is
controlled efficiently by an applied magnetic field and can be made finite to
cause the formation of a Bose-Einstein condensate (BEC). Studies of magnon
condensation in a growing number of magnetic materials provide a unique window
into an exciting world of quantum phase transitions (QPT) and exotic quantum
states.Comment: 17 pages, 3 figure
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