Air-coupled ultrasound as an accurate and reproducible method for bonding assessment of glued timber

Glued timber products are widely used in construction; therefore, it is necessary to develop non-destructive bonding quality assessment methods for long-term structural health monitoring. Air-coupled ultrasound (ACU) inspection is a novel technique, with phenomenal improvements in reproducibility compared to traditional contact ultrasonics, unlimited scanning possibilities, and a high potential for delamination detection in wood products. As part of an ongoing project, glued timber samples of 10mm thickness with artificial glue line defects were inspected. A normal through-transmission set-up with 120kHz transducers allowed for successful and accurate imaging of the geometry of glued and non-glued areas in all inspected objects. The influence of wood heterogeneity and the reproducibility of ACU amplitude measurements were analysed in detail, identifying the main sources of variation. Future work is planned for the inspection of more complex glued timber object

Functional expression of a human TCRβ gene in transgenic mice

A functionally rearranged TCRβ (Tcrb) gene was isolated from a cloned human T helper cell recognizing the CS.T3 epitope of Plasmodium falciparum with HLA-DR2. Transgenic mice were generated by co-injection of the human gene together with the mouse Tcrb enhancer. Analysis of transgenic mice shows that the functional Tcrb gene of xenogenic, i.e. human, origin exerts allelic exclusion of endogenous Tcrb genes. Cytofluorometric analysis revealed expression of the human TCRβ chain on virtually all thymocytes and peripheral T cells together with endogenous TCRβ chains and CD3 components. No surface expression of mouse TCRβ chain or rearrangement of endogenous Tcr genes was detectable. Expression of the hybrid receptor causes a reduction in the number of thymocytes and a bias for CD4+CD8− T cells in the thymus as compared with non-transgenic littermates. Peripheral transgenic T cells mount a normal prollferative response against allogenelc targets in mixed lymphocyte reactions. These results show that a hybrid mouse/human TCR is able to pass positive and negative selection in the thymus, and is functional in transgenic mic

Utilization of Bio Ashes in Cement-based Materials: A Case Study in Cooperation with Pulp and Paper and Energy Production Industries in Sweden

Worldwide increased concern of the CO2 emissions has led to the replacement of coal by biomass in combustion-based power plants. However, this would cause the scarcity of fly ash, one of the most well-known rest products from coal combustion, which is used as supplementary cementitious materials (SCM) in construction sector to reduce the large environmental footprint of cement production. Seeking to find alternative SCMs, this article aims to demonstrate the viability of using bio ashes in Sweden as SCM, which, due to lack of studies validating their value, are landfilled today. According to the obtained results, bio ashes produced at pulp and paper industries have a considerably consistent chemical composition and exhibit a satisfactory pozzolanic behaviour. Nevertheless, according to the conclusions of this study, the pozzolanicity of these alternative binders is not reflected equally with respect to the most known reactivity tests for common SCMs. The results imply that although “R3” tests method infers the pozzolanic characteristics of the bio ashes in focus of this study, the “activity index test” as well as “calcium consumption test” indicate otherwise

Multiplicity distributions for jet parton showers in a medium

The "jet-quenching" interpretation of suppressed high-pT hadron production at RHIC implies that jet multiplicity distributions and jet-like particle correlations in heavy-ion collisions at RHIC and LHC differ strongly from those seen at e+e- or pp colliders. Here, we present an approach for describing the changes induced by the medium, which implements jet quenching as a probabilistic medium-modified parton shower, treating leading and subleading parton splittings on an equal footing. We show that the strong suppression of single inclusive hadron spectra measured in Au-Au collisions at RHIC implies a characteristic distortion of the single inclusive distribution of soft partons inside the jet. We determine, as a function of jet energy, to what extent the soft jet fragments can be measured above some momentum cut.Comment: 4 pages, 2 eps-figures. Talk given at Quark Matter 2005, Budapest, 4-9 Aug 200

Transverse Dynamics of Hard Partons in Nuclear Media and the QCD Dipole

We derive the non-abelian generalization of the Furry approximation which describes the transverse dynamical evolution of a hard projectile parton inside a spatially extended colour target field. This provides a unified starting point for the target rest frame description of the nuclear dependence of a large class of observables. For the case of the virtual gamma -> q-qbar photoabsorption cross section, we investigate then in detail under which conditions the nuclear dependence encoded in the Furry wavefunctions can be parametrized by a q-qbar QCD dipole cross section. The important condition is colour triviality, i.e., the property that for arbitrary N-fold rescattering contributions the only non-vanishing colour trace is N_c C_F^N. We give proofs for the colour triviality of the inelastic, diffractive and total photoabsorption cross section measured inclusively or with one jet resolved in the final state. Also, we list examples for which colour interference effects remain. Colour triviality allows us to write the gamma -> q qbar contribution to the DIS nuclear structure function F_2 for small Bjorken x in terms of a path integral which describes the transverse size evolution of the q-qbar pair in the nuclear colour field. This expression reduces in an opacity expansion to the N=1 result of Nikolaev and Zakharov, and in the eikonal approximation to the Glauber-type rescattering formulas first derived by Mueller. In the harmonic oscillator approximation of the path integral, we quantify deviations from the eikonal limit. Their onset is characterized by the scales L/l_f and E_t L which relate the longitudinal extension L of the nuclear target to the coherence length l_f and the total transverse energy E_t accumulated by the q-qbar pair.Comment: 23 pages, LaTeX, 12 eps-figures included, typos corrected, discussion extended, to appear in NP

Static behavior of cob: Experimental testing and finite element modeling

The aim of this paper is to implement a numerical model to reproduce the nonlinear behavior of cob walls under shear loading. Axial compression, pull-off, and diagonal compression tests were carried out to derive the mechanical parameters. In addition, the stress-strain relationships, the nonlinear behavior, and the failure modes were defined. The experimental results were then used to calibrate a finite-element model. The material behavior was simulated through a macromodeling approach adopting the total strain rotating crack model. A sensitivity analysis was conducted to assess the effects of varying the parameters with higher uncertainty on the structural behavior. The numerical model achieved good correspondence with the experimental results in terms of simulation of the shear stress-shear strain relationship and of damage pattern. (c) 2019 American Society of Civil Engineers.- The authors wish to express their gratitude to Mr. Andre Gardei for his important support in the experimental program and to Mr. Andreas Barner and Ms. Manuela Peuschel for their support with photogrammetric analyses. This study was funded by the European Commission within the framework of the project NIKER (Grant No. 244123) dealing with improving immovable Cultural Heritage assets against the risk of earthquakes. The study was partly financed by FEDER funds through the Competitivity Factors Operational Programme (project POCI-01-0145-FEDER-007633) and by national funds through the Portuguese Foundation for Science and Technology (project PTDC/ECM-EST/2777/2014 and Grant No. SFRH/BPD/97082/2013)

Nonlinear QCD Evolution: Saturation without Unitarization

We consider the perturbative description of saturation based on the nonlinear QCD evolution equation of Balitsky and Kovchegov (BK). Although the nonlinear corrections lead to saturation of the scattering amplitude locally in impact parameter space, we show that they do not unitarize the total cross section. The total cross section for the scattering of a strongly interacting probe on a hadronic target is found to grow exponentially with rapidity. The origin of this violation of unitarity is the presence of long range Coulomb fields away from the saturation region. The growth of these fields with rapidity is not tempered by the nonlinearity of the BK equation.Comment: 4 pages, RevTe

Energy Dependence of the Cronin Effect from Non-Linear QCD Evolution

The non-linear evolution of dense partonic systems has been suggested as one of the novel physics mechanisms relevant to the dynamics of hadron-nucleus and nucleus-nucleus collisions at collider energies. Here we study to what extent the description of Cronin enhancement in the framework of this non-linear evolution is consistent with the recent observation in 200 AGeV d--Au collisions at the Relativistic Heavy Ion Collider. We solve the Balitsky-Kovchegov evolution equation numerically for several initial conditions encoding Cronin enhancement. We find that the properly normalized nuclear gluon distribution is suppressed at all momenta relative to that of a single nucleon. Calculating the resulting spectrum of produced gluons in p-A and A-A collisions, we establish that the nonlinear QCD evolution is unable to generate a Cronin type enhancement, and that it quickly erases any such enhancement which may be present at lower energies.Comment: 4 pages, Latex, 3 eps-figure

A yeast-based bioassay for the determination of functional and non-functional estrogen receptors

The response to endocrine therapy of breast cancer is not entirely predictable from hormone receptor status alone since some point mutated or splicing variants of the estrogen receptor (ER) show altered biological activities. In order to characterize the activities of all forms of ER in a heterogeneous breast tumor, a functional assay in Saccharomyces cerevisiae was developed. Total RNA isolated from breast cancer cells and one breast cancer specimen was reverse transcribed and the ER cDNA was amplified by PCR. The products were then cloned into an expression vector by in vivo homologous recombination in yeast. The yeast strain carries a reporter gene (ADE2) coupled to an estrogen response element. Activation of the reporter by ER yielded white colonies whereas lack of ER activity produced red colonies. This permitted the testing for functionality of individual ER molecules and subsequent analysis by rescuing of the ER expression plasmids and complete DNA sequencing. This simple visual test allows discrimination between wild-type ER, constitutively active ER and inactive E

Metabolomic serum abnormalities in dogs with hepatopathies

Hepatopathies can cause major metabolic abnormalities in humans and animals. This study examined differences in serum metabolomic parameters and patterns in left-over serum samples from dogs with either congenital portosystemic shunts (cPSS, n = 24) or high serum liver enzyme activities (HLEA, n = 25) compared to control dogs (n = 64). A validated targeted proton nuclear magnetic resonance spectroscopy platform was used to assess 123 parameters. Principal component analysis of the serum metabolome demonstrated distinct clustering among individuals in each group, with the cluster of HLEA being broader compared to the other groups, presumably due to the wider spectrum of hepatic diseases represented in these samples. While younger and older adult control dogs had very similar metabolomic patterns and clusters, there were changes in many metabolites in the hepatopathy groups. Higher phenylalanine and tyrosine concentrations, lower branched-chained amino acids (BCAAs) concentrations, and altered fatty acid parameters were seen in cPSS dogs compared to controls. In contrast, dogs with HLEA had increased concentrations of BCAAs, phenylalanine, and various lipoproteins. Machine learning based solely on the metabolomics data showed excellent group classification, potentially identifying a novel tool to differentiate hepatopathies. The observed changes in metabolic parameters could provide invaluable insight into the pathophysiology, diagnosis, and prognosis of hepatopathies.Peer reviewe