52,655 research outputs found
Scanlan, E T (Eric Thomas), VX65951
No full textThis record was harvested from a previous catalogue system and will be withdrawn in 2025. Information in this record may be superseded or incomplete. Visit this record in UMA's new catalogue at: https://archives.library.unimelb.edu.au/nodes/view/415531Surname: SCANLAN. Given Name(s) or Initials: E T (ERIC THOMAS). Military Service Number or Last Known Location: VX65951. Missing, Wounded and Prisoner of War Enquiry Card Index Number: 42608.236177
Item: [2016.0049.47792] "Scanlan, E T (Eric Thomas), VX65951
On axisymmetric adhesive joints with graded interface stiffness
No full textAn improved analytical model is presented for the stress analysis of interface stiffness graded axisymmetric adhesive joints. The governing integro-differential equation of the problem is obtained through a variational method which minimizes the complementary energy of the bonded assembly. The joint is composed of similar or dissimilar polar anisotropic and/or isotropic adherends and a functionally modulus graded bondline (FMGB) adhesive. The elastic modulus of the adhesive is functionally graded along the bondlength by assuming smooth modulus profiles which reflect the behavior of practically producible graded bondline. Influence of non-zero radial stresses in the bonded system on shear and normal stresses is evaluated. The stress distribution predicted by this refined model is compared with that of mono-modulus bondline (MMB) model for the same axial tensile load in order to estimate reduction in shear and normal stress peaks in the bondline and the adherends. A systematic parametric study indicates that an optimum joint strength can be achieved by employing a stiffness graded bondline with an appropriate combination of geometrical and material properties of the adherends. This model can also be applied to examine the effects of loss of interface stiffness due to an existing defect and/or damage in the bondlin
The TRbeta-selective agonist, GC-1, stimulates mitochondrial oxidative processes to a lesser extent than triiodothyronine
No full textJ Endocrinol. 2010 Jun;205(3):279-89. Epub 2010 Apr 1.
The TRbeta-selective agonist, GC-1, stimulates mitochondrial oxidative processes to a lesser extent than triiodothyronine.
Venditti P, Chiellini G, Di Stefano L, Napolitano G, Zucchi R, Columbano A, Scanlan TS, Di Meo S.
SourceDipartimento delle Scienze Biologiche, Sezione di Fisiologia, Università di Napoli Federico II, Via Mezzocannone 8, I-80134 Napoli, Italy. [email protected]
Abstract
Specific tissue responses to thyroid hormone are mediated by the hormone binding to two subtypes of nuclear receptors, TRalpha and TRbeta. We investigated the relationship between TRbeta activation and liver oxidative metabolism in hypothyroid rats treated with equimolar doses of triiodothyronine (T(3)) and GC-1, a TRbeta agonist. T(3) treatment produces increases in O(2) consumption and H(2)O(2) production higher than those elicited by GC-1. The greater effects of T(3) on oxidative processes are linked to the higher hormonal stimulation of the content of respiratory chain components including autoxidizable electron carriers as demonstrated by the measurement of activities of respiratory complexes and H(2)O(2) generation in the presence of respiratory inhibitors. It is conceivable that these differential effects are dependent on the inability of GC-1 to stimulate TRalpha receptors that are likely involved in the expression of some components of the respiratory chain. The greater increases in reactive oxygen species production and susceptibility to oxidants exhibited by mitochondria from T(3)-treated rats are consistent with their higher lipid and protein oxidative damage and lower resistance to Ca(2)(+) load. The T(3) and GC-1 effects on the expression levels of nuclear respiratory factor-1 and -2 and peroxisome proliferator-activated receptor-gamma coactivator-1alpha suggest the involvement of respiratory factors in the agonist-linked changes in mitochondrial respiratory capacities and H(2)O(2) production.
PMID:20360308[PubMed - indexed for MEDLINE
Biosynthesis of 3-Iodothyronamine (T1AM) is dependent on the sodium-iodide symporter and thyroperoxidase but does not involve extrathyroidal metabolism of T4
No full text3-Iodothyronamine (T1AM) is an endogenous thyroid hormone derivative with unknown biosynthetic origins. Structural similarities have led to the hypothesis that T1AM is an extrathyroidal metabolite of T 4. This study uses an isotope-labeled T4 [heavy-T 4 (H-T4)] that can be distinguished from endogenous T 4 by mass spectrometry, which allows metabolites to be identified based on the presence of this unique isotope signature. Endogenous T 1AM levels depend upon thyroid status and decrease upon induction of hypothyroidism. However, in hypothyroid mice replaced with H-T4, the isotope-labeled H-T3 metabolite is detected, but no isotope-labeled T1AM is detected. These data suggest that T1AM is not an extrathyroidal metabolite of T4, yet is produced by a process that requires the same biosynthetic factors necessary for T4 synthesis
Fragments of bacterial endoglycosidase S and immunoglobulin G reveal subdomains of each that contribute to deglycosylation
No full textEndoglycosidase S (EndoS) is a glycoside-hydrolase secreted by the bacterium Streptococcus pyogenes. EndoS preferentially hydrolyzes the N-linked glycans from the Fc region of IgG during infection. This hydrolysis impedes Fc functionality and contributes to the immune evasion strategy of S. pyogenes. Here, we investigate the mechanism of human serum IgG deactivation by EndoS. We expressed fragments of IgG1 and demonstrated that EndoS was catalytically active against all of them including the isolated CH2 domain of the Fc domain. Similarly, we sought to investigate which domains within EndoS could contribute to activity. Bioinformatics analysis of the domain organization of EndoS confirmed the previous predictions of a chitinase domain and leucine-rich repeat but also revealed a putative carbohydrate binding module (CBM) followed by a C-terminal region. Using expressed fragments of EndoS, circular dichroism of the isolated CBM, and a CBM-C-terminal region fusion revealed folded domains dominated by β sheet and α helical structure, respectively. Nuclear magnetic resonance analysis of the CBM with monosaccharides was suggestive of carbohydrate binding functionality. Functional analysis of truncations of EndoS revealed that, whereas the C-terminal of EndoS is dispensable for activity, its deletion impedes the hydrolysis of IgG glycans
Mapping customer needs to engineering characteristics: an aerospace perspective for conceptual design
No full textDesigning complex engineering systems, such as an aircraft or an aero-engine, is immensely challenging. Formal Systems Engineering (SE) practices are widely used in the aerospace industry throughout the overall design process to minimise the overall design effort, corrective re-work, and ultimately overall development and manufacturing costs. Incorporating the needs and requirements from customers and other stakeholders into the conceptual and early design process is vital for the success and viability of any development programme. This paper presents a formal methodology, the Value-Driven Design (VDD) methodology that has been developed for collaborative and iterative use in the Extended Enterprise (EE) within the aerospace industry, and that has been applied using the Concept Design Analysis (CODA) method to map captured Customer Needs (CNs) into Engineering Characteristics (ECs) and to model an overall ‘design merit’ metric to be used in design assessments, sensitivity analyses, and engineering design optimisation studies. Two different case studies with increasing complexity are presented to elucidate the application areas of the CODA method in the context of the VDD methodology for the EE within the aerospace secto
3-Iodothyronamine (T(1)AM) induces variation in phosphorylation pattern of tyrosine residues in rat heart
No full textModeling of modulus graded axisymmetric adhesive joints
No full textThis study presents a refined theoretical framework for the stress analysis of modulus graded axisymmetric adhesive joints which takes into account the radial stresses in the bonded assembly. This semi-analytical is based on a variational method which minimizes the complementary energy of the bonded system. The joint consists of similar or dissimilar polar anisotropic composite adherends or metallic adherends and a functionally modulus graded bondline (FMGB) adhesive. The elastic modulus of the adhesive is functionally graded along the bondlength by assuming smooth modulus profiles which reflect the behavior of practically producible graded bondline. The stress distribution predicted by this refined model is compared with that of MMB model which also accounts for in the bonded system to estimate reduction in shear and peel stress peaks in the bondline. The axisymmetric stress analysis reveals that the peel and shear stress peaks in the FMGB are much smaller and the stress distribution is more uniform along its length than those of mono-modulus bondline (MMB) adhesive joints under the same axial tensile load. A systematic parametric study has been conducted by selectively perturbing the material and geometrical properties of the joint in order to study their influence onstress distribution in the bondline. Furthermore, the results suggest that the peel and shear strengths can be optimized by spatially controlling the modulus of theadhesive
Cardioprotective effect of 3-iodothyronamine in perfused rat heart subjected to ischemia and reperfusion.
No full text3-iodothyronamine (T(1)AM) is an endogenous compound which shares structural and functional features with biogenic amines and is able to interact with a specific class of receptors, designed as trace amine associated receptors. T(1)AM has significant physiological effects in mammals and produces a reversible, dose-dependent negative inotropic and chronotropic effect in heart. The aim of the present study was to investigate if T(1)AM is able to reduce irreversible tissue injury in isolated rat hearts subjected to ischemia and reperfusion, as evaluated by triphenyltetrazolium chloride staining. We observed that T(1)AM reduced infarct size at concentrations (125 nM to 12.5 μM) which did not produce any significant hemodynamic action. The dose-response curve was bell-shaped and peaked at 1.25 μM. T(1)AM-induced cardioprotection was completely reversed by the administration of chelerythrine and glibenclamide, suggesting a protein kinase C and K (ATP) (+) -dependent pathway, while it was not additive to the protection induced by cyclosporine A, suggesting modulation of mitochondrial permeability transition. At cardioprotective concentration, T(1)AM reduced the time needed for cardiac attest during ischemia, but it did not affect sarcoplasmatic reticulum Ca(2+) handling, as demonstrated by unaltered ryanodine receptor binding properties. In conclusion, in isolated rat heart T(1)AM produces a cardioprotective effect which is mediated by a protein kinase C and K (ATP) (+) -dependent pathway and is probably linked to modulation of mitochondrial permeability transition and/or ischemic arrest time
Evaluating design decisions in real-time using operations modelling
No full textContemporary design processes of large aerospace products are rigidly focused on customer specifications in order to meet their expectations. Life cycle costs, design space exploration and value engineering are neglected, often leading to substantial cost overruns and delivery delays. Moreover, customer specifications are not scrutinized and design decisions are made ignoring potential operational knowledge. Value-driven design suggests a new approach using flexible customer specifications in order to find optimal designs by exploring the solution space. One aspect of this optimization is the simulation of the anticipated operational life of a product in order to gain operational knowledge and analyse customer specifications. This paper suggests that an operational simulation can be used actively or reactively by designers during the design process to improve a product. It is investigated how an operational simulation can act as a design decision support tool and how it can react to customer specifications. Answers are presented by means of a simulation model recreating the operational life of a Search-and-Rescue Unmanned Air Vehicle developed in parallel at the University of Southampton. The simulation's ability for acting as a decision support tool is explored by conducting a fuel tank size optimization. Reactive capabilities are explored by calculating the surplus value of using UAVs. This exemplifies the derivation of product specifications as the simulation reveals the value and hence usefulness of given customer specifications. It is shown that operational simulations benefit designers and overall product value by analysing product specifications and guiding designers to more informed design decision
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