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Experimental autoimmune uveoretinitis (EAU) is an animal model of non-infectious uveitis and is developed by immunization with retinal antigen, interphotoreceptor retinoid-binding protein (IRBP). Nuclear factor erythroid 2- (NF-E2-) related factor 2 (Nrf2) is responsible for regulating antioxidant and inflammatory responses. In this study, we investigated the role of Nrf2 on the development of EAU. Clinical and pathological examination demonstrated that retinal inflammation was exacerbated in Nrf2 knockout (Nrf2 KO) mice compared to wild type (WT) mice, and the expression of inflammatory cytokines (IFN-γ, IL-6, and IL-17) in the retina was significantly elevated in Nrf2 KO mice. GFAP positive cells (astrocytes) and Iba-1 positive cells (microglia cells) in the retina were more numerous in Nrf2 KO mice compared to WT mice. Furthermore, we examined the suppressive effect of the Nrf2 activator CDDO-Im (2-cyano-3,12 dioxooleana-1,9 dien-28-oyl imidazoline) on the development of EAU. The treatment with CDDO-Im significantly reduced the clinical and pathological score of EAU compared to those of vehicle-treated mice. These findings suggest that Nrf2 plays a regulatory role in the pathogenesis of autoimmune uveoretinitis and the activation of the Nrf2 system may have therapeutic potential for protecting vision from autoimmune neuroinflammation. [ABSTRACT FROM AUTHOR]

Mesoscale constitutive models of frost-damaged concrete are developed in this study through numerical simulation using a two-dimensional rigid body spring model (RBSM). The aim of the simulation is to predict the macrobehavior of frost-damaged concrete subjected to mechanical loading. The models also clarify the difference in failure behavior of concrete with and without frost damage. Zero strength elements and the concept of mesoscale plastic tensile strain are introduced into the normal RBSM springs to consider the experimentally observed cracking and plastic deformation caused by frost damage. The difference in the effect of frost damage on compression and tension behavior as found in the experiments is clearly predicted. Finally, analysis of a notched beam subjected to bending after different degrees of frost damage is carried out. The resulting load-deflection curves agree well with those obtained in the experiments. These good correlations confirm the applicability of the mesoscale model for predicting the macrobehavior of frost-damaged concrete. CE Database subject headings: Constitutive models; Frost; Concrete; Damage; Mechanical properties.

This study attempted to develop a model for the stress-strain relationship in compression of frost-damaged concrete subjected to fatigue loading. Concrete specimens were prepared and exposed to freeze-thaw cycles followed by application of static and fatigue loading. The strains induced during the freeze-thaw test were carefully measured as well as during a mechanical loading test. It was found that the static strength and the fatigue life of concrete decreases as increasing irreversible tensile strain was induced by frost action. A stress-strain model for frost-damaged concrete under application of static and fatigue loading based on the degradation of initial stiffness caused by frost damage was presented. The degradation of initial stiffness for damaged concrete was empirically formulated as a function of remaining expansion caused by freeze-thaw cycles. The plastic strain under the application of mechanical static and fatigue loading for frost-damaged concrete is higher than that for original concrete. Therefore, plastic strain for damaged concrete was formulated as not only the function of strain level under mechanical loading, but also the function of irreversible strain caused by frost action. The unloading and reloading stiffness factors were introduced to explain the change of stiffness as increasing the number of loading cycles by considering the effect of the degree of frost damage. DOI: 10.1061/(ASCE)0899-1561 (2008)20:1 (37) CE Database subject headings: Strain; Stress; Freeze-thaw; Fatigue; Fatigue life; Stiffness; Plasticity; Cracking.

Purpose: To determine the effect of injection of IL-2/anti-IL-2 antibody (IL-2 complex) together with rapamycin on the development of experimental autoimmune uveoretinitis (EAU). Methods: C57BL/6J mice were immunized with human interphotoreceptor retinoid-binding protein peptide. The immunized mice were injected intraperitoneally with PBS, IL-2 complex, rapamycin, or IL-2 complex/rapamycin on days 1, 2, 3, and 4 (induction phase) or days 10, 11, 12, and 13 (effector phase) after immunization. Results: Expansion of CD4+Foxp3+ regulatory T cells in draining lymph nodes was observed in IL-2 complex and IL-2 complex/rapamycin-treated mice. Although injection of IL-2 complex alone was not capable of decreasing the clinical score of EAU, injection of IL-2 complex/rapamycin significantly delayed the onset of EAU. In contrast, the treatment with IL-2 complex alone or IL-2 complex/rapamycin during effector phase failed to suppress EAU. Conclusions: These findings suggest the potential limitations of IL-2 complex or IL-2 complex/rapamycin during EAU. [ABSTRACT FROM AUTHOR]

This paper will examine in detail a posttensioned concrete (PTC) girder bridge with dapped-end connections, with a re-entrant corner diagonal crack that is typical of these types of bridges. This paper aims to identify the possible causes of the existing damage and the potential modes of failure of the bridge's girder using nonlinear finite-element analysis (FEA). Failure analysis of the bridge girder will consider the effects of supplying the bridge with different dapped reinforcements and subjecting the bridge's prestressed tendons to losses in their prestressing forces. Various failure scenarios and cases will be simulated in numerical models. Numerical analysis results will be compared with design guidelines for bridge girders. Overall, the investigative results indicated that the combined impacts of insufficient hanger reinforcement and prestress losses in the girder's end-section was the probable cause of the bridge's re-entrant corner diagonal crack. [ABSTRACT FROM AUTHOR]

In this article, we report a preference of homochiral-type ligation of BINAP that produces SS-type ligand assembly onto the Au11 clusters protected by diphosphine S,S-DIOP. The Au11 clusters synthesized and isolated are Au11(S,S-DIOP)4(rac-/R-/S-BINAP), and their optical/chiroptical responses are characterized. Absorption spectra of these Au11 clusters are almost identical to each other, but their CD profiles are dependent on the handedness of BINAP. In Au11(S,S-DIOP)4(rac-BINAP), the yield of S-BINAP or R-BINAP coordination is roughly comparable, but we found a small but distinctive preference in the S-BINAP ligation; that is, homochiral-type (SS-type) ligand assembly formation. Quantum chemical calculations for simplified model clusters suggest equal contributions of S- and R-form BINAP coordination. The experimentally-observed preference of homochiral-type ligation can then be due to that of the whole ligand structures and assemblies involving interligand interactions. Chiral sorting and amplification processes through the assembly control of homochirality or heterochirality are of primary importance for the development of enantioselective reactions, so we anticipate this finding will contribute to further understanding of such processes based on various metal clusters with chiral ligands. [ABSTRACT FROM AUTHOR]

The retinal pigment epithelium (RPE) is a polarized, monolayer of pigmented cells that forms the outer retinal layer. A key function of the RPE is to maintain the integrity of the photoreceptors mainly via phagocytosis and recycling of the digested photoreceptor outer segments. Moreover, RPE cells are a major source of inflammatory cytokines and chemokines, which play important roles in the activation of other immune cells under inflammatory conditions in the posterior segment of the eye. Dehydroxymethylepoxyquinomicin (DHMEQ) is a NF-κB inhibitor and its structure is related to that of epoxyquinomicin C, which is an antibiotic. The present study evaluated the anti-inflammatory effects of DHMEQ on a human retinal pigment epithelial cell line (ARPE-19). It was revealed that high concentrations of DHMEQ (100 µg/ml) induced apoptosis and necrosis of tumor necrosis factor (TNF)-α-stimulated ARPE-19 cells. Furthermore, the percentage of intercellular adhesion molecule 1 (ICAM-1)-positive TNF-α-stimulated cells was significantly reduced in the presence of DHMEQ (10 µg/ml), as determined by flow cytometry. It was also demonstrated that DHMEQ exposure significantly decreased the levels of interleukin (IL)-8 and monocyte chemoattractant protein-1 (MCP-1) in the supernatant of cultured ARPE-19 cells as determined by ELISA. Moreover, the protein expression levels of IL-8 and MCP-1 were significantly reduced in ARPE-19 cells exposed to DHMEQ compared with cells exposed to dexamethasone. PCR array analysis revealed that DHMEQ reduced the expression levels of MCP-1, ICAM-1, IL-6, Toll-like receptor (TLR)2, TLR3 and TLR4. Therefore, the present results indicated that DHMEQ has anti-inflammatory effects on TNF-α-stimulated ARPE-19 cells. Thus, DHMEQ may have therapeutic potential for TNF-α-mediated inflammatory disorders of the eye. [ABSTRACT FROM AUTHOR]

As bridge deck slabs experience the direct impact of repeated concentrated wheel loads, they are more susceptible to fatigue‐related damage than other bridge components. In this context, a fatigue life prediction method for reinforced concrete (RC) bridge decks has been developed based on failure mechanisms of RC slabs tested under moving wheel loads. Initially, the formulas encompassed shear strength and S–N equations, accommodating variations in environmental and support conditions, are proposed to facilitate the fatigue life prediction of slabs exposed to constant moving wheel load. Subsequently, a model for shear strength degradation formulated using experimental findings on beam‐like elements is utilized in predicting the fatigue life of slabs subjected to stepwise moving wheel loads. The validity of the proposed method was established by comparing its results with previous experimental data. Notably, compared with the existing prediction equation, the proposed method exhibited more accurate fatigue life prediction results. [ABSTRACT FROM AUTHOR]

In this article, the chiroptical responses of Au9 clusters protected by chiral/achiral mixed bidentate phosphine ligands are reported. The mixed phosphine we use is (S)-BINAP/Xantphos in the molar ratio of 1/0 (= pure (S)-BINAP), 3/1, 1/1, or 0/1 (= pure Xantphos), where BINAP and Xantphos represent 2,2′-bis(diphenylphosphino)-1,1′-binaphthyl and 4,5-bis(diphenylphosphino)-9,9-dimethylxanthene, respectively. Electronic absorption spectra of the clusters are similar between the samples with different molar diphosphine ratios, but the chiroptical activity or g-factor decreases nonlinearly with an increase in the fraction of Xantphos. Quantum chemical calculations and geometrical quantifications based on the Hausdorff chirality measure (HCM) for model Au9 cluster species suggest that (i) two types of metal core structures with pseudo-P- and M-chirality are found, and their appropriate contributions would cancel out the chiroptical response in the low-energy region; (ii) the origin of optical activity in pure (S)-BINAP-protected Au9 clusters can mainly be attributed to the metal core chirality, whereas that of other mixed-ligand protected clusters would be due to the chiral ligand arrangement. This work demonstrates that the modulation of chiroptical activity in Au9 clusters by chiral/achiral mixed-diphosphine ligation is controlled by the difference in the degree of chirality existing in the cluster core and/or the ligand array. [ABSTRACT FROM AUTHOR]

The experimental and analytical study are attempted to clarify the static and fatigue behavior of mortar with blast furnace slag (BFS) sand as fine aggregates in compression in air and water. The cylindrical BFS mortar specimens were used for static and fatigue compression tests in air and water and results are compared with those of mortar using crushed sand (CS). The fatigue load was applied in the form of sine signal with a constant amplitude and the frequency of 5 Hz. The stress level is varied from 60%, 70% and 80% of the uniaxial compressive strength. The experimental results disclose that BFS mortar exhibits more fatigue life compared to CS mortar in air, while it is similar in water. Thereafter, the stress-strain relationships for each mortar under monotonic loading are formulated. Moreover, a simplified fatigue model for the assessment of plastic strain, total strain and fracture parameter at different number of loading cycles and for prediction of fatigue life is also proposed. [ABSTRACT FROM AUTHOR]

Simple, separable, unital, monotracial and nuclear $$\mathrm {C}^{*}$$ -algebras are shown to have finite nuclear dimension whenever they absorb the Jiang-Su algebra $$\mathcal {Z}$$ tensorially. This completes the proof of the Toms-Winter conjecture in the unique trace case. [ABSTRACT FROM AUTHOR]

For any unital separable simple infinite-dimensional nuclear C-algebra with finitely many extremal traces, we prove that $$ \mathcal{Z} $$-absorption, strict comparison and property (SI) are equivalent. We also show that any unital separable simple nuclear C-algebra with tracial rank zero is approximately divisible, and hence is $$ \mathcal{Z} $$-absorbing. [ABSTRACT FROM AUTHOR]

Allowing for the tension stiffening effects resulting from the bond between steel reinforcement and surrounding concrete leads to effective deformation analysis of reinforced concrete (RC) members when using a nonlinear finite element analysis modeled on the smeared crack concept. Nowadays, externally bonded fiber reinforced polymer (FRP) composites are widely used for strengthening existing RC structures. However, it remains unclear to what extent the tension stiffening of postcracking concrete is quantitatively influenced by the addition of FRP composites, as a result of the bond between the FRP and the concrete substrate. This article presents a discrete model, which is based on rigid body spring networks (RBSN), for investigating the tension stiffening behavior of concrete in FRP-strengthened RC tensile members. A two-parameter fracture energy-based model was deployed to represent the bond-slip behavior of the FRP-to-concrete interface. The reliability of the RBSN model was verified through comparisons with previous test results. Further parametric analysis indicates that the tension stiffening of concrete is hardly influenced by the addition of FRP composites before the yield of steel reinforcement has occurred although concrete crack patterns and crack widths may be influenced by the bond-slip behavior of the FRP-to-concrete interface. [ABSTRACT FROM AUTHOR]

In addition to providing standard surgical treatment that removes the plaque and infected tissues, medications that can regenerate periodontal tissue are also required in the treatment of periodontal disease. As a form of regenerative medication, various growth factors are expected to be used while treating periodontal disease. A protein-like growth factor is often developed as a lyophilized product with dissolution liquid, considering its instability in the solution state. We have clarified that the formulation for periodontal disease needs to be viscous. When the lyophilized product was dissolved using a sticky solution, various problems were encountered, difficulty in dissolving and air bubbles, for example, and some efforts were needed to prepare the formulation. In this research, to identify the problem of preparing a viscous formulation, a lyophilized product (placebo) and sticky liquid were prepared by using vial and ampoule as the conventional containers. Based on these problems, a prototype administration device was developed, and its functionality was confirmed. As a result, it was suggested that the device with a useful mixing system that could shorten the preparation time was developed. [ABSTRACT FROM AUTHOR]

A two-dimensional (2D) nonlinear numerical analysis code by using the rigid body spring method (RBSM) was developed by the writers at Hokkaido University to simulate the behavior of reinforced concrete (RC) members strengthened with fiber-reinforced polymer (FRP) sheets. The code supports the nonlinear constitutive laws for the different materials and nonlinear bond stress-slip relationships for steel-concrete and FRP sheet-concrete interfaces. This study uses the aforementioned code to examine the uniaxial tension behavior of RC members strengthened with carbon fiber sheets (CFS). Experimental results are compared with relevant numerical outputs to validate the model and confirm its ability to simulate the experimental observations. This study also assesses the influence of the amount of CFS strengthening on the tension-stiffening behavior of strengthened members. Finally, this research also suggests new analytical expressions for the average stress-strain relationships of concrete and steel in tension in the presence of stiffening contributions from internal steel reinforcement bars and externally bonded CFS reinforcement. [ABSTRACT FROM AUTHOR]

Peroxisomes require peroxin (Pex) proteins for their biogenesis. The interaction between Pex3p, which resides on the peroxisomal membrane, and Pex19p, which resides in the cytosol, is crucial for peroxisome formation and the post-translational targeting of peroxisomal membrane proteins (PMPs). It is not known how Pex3p promotes the specific interaction with Pex19p for the purpose of PMP translocation. Here, we present the three-dimensional structure of the complex between a cytosolic domain of Pex3p and the binding-region peptide of Pex19p. The overall shape of Pex3p is a prolate spheroid with a novel fold, the 'twisted six-helix bundle.' The Pex19p-binding site is at an apex of the Pex3p spheroid. A 16-residue region of the Pex19p peptide forms an α-helix and makes a contact with Pex3p; this helix is disordered in the unbound state. The Pex19p peptide contains a characteristic motif, consisting of the leucine triad (Leu18, Leu21, Leu22), and Phe29, which are critical for the Pex3p binding and peroxisome biogenesis. [ABSTRACT FROM AUTHOR]

Abstract: For projectionless -algebras absorbing the Jiang–Su algebra tensorially, we study a kind of the Rohlin property for automorphisms. We show that the crossed products obtained by automorphisms with this Rohlin property also absorb the Jiang–Su algebra tensorially under a mild technical condition on the -algebras. In particular, for the Jiang–Su algebra we show the uniqueness up to outer conjugacy of the automorphism with this Rohlin property. [Copyright &y& Elsevier]

Let G be an inductive limit of finite cyclic groups, and A be a unital simple projectionless C*-algebra with K1(A) ≅ G and a unique tracial state, as constructed based on dimension drop algebras by Jiang and Su. First, we show that any two aperiodic elements in Aut(A)/WInn(A) are conjugate, where WInn(A) means the subgroup of Aut(A) consisting of automorphisms which are inner in the tracial representation. In the second part of this paper, we consider a class of unital simple C*-algebras with a unique tracial state which contains the class of unital simple A핋-algebras of real rank zero with a unique tracial state. This class is closed under inductive limits and crossed products by actions of ℤ with the Rohlin property. Let A be a TAF-algebra in this class. We show that for any automorphism α of A there exists an automorphism ᾶ of A with the Rohlin property such that ᾶ and α are asymptotically unitarily equivalent. For the proof we use an aperiodic automorphism of the Jiang-Su algebra. [ABSTRACT FROM AUTHOR]

Based on a series of experimental tests on notched concrete beams externally bonded with unidirectional fiber-reinforced polymer (FRP) sheets, this paper investigates the bond characteristics of FRP sheet-concrete interfaces under dowel load, which acts vertically on the FRP sheet and leads to a mix-mode interface peeling. The peeling properties of FRP sheet-concrete interfaces under the dowel load are evaluated in terms of their interface dowel load-carrying capacity, critical interface peeling angle, and interface peeling fracture energy. Experimental parameters include strength of concrete substrate, tension stiffness of FRP sheets, properties of bonding adhesives, concrete surface treatment methods, and length of precrack set between the FRP sheet and concrete substrate. Analytical models clarifying the relationships among the interface dowel load-carrying capacity, the interface peeling angle, and the interface peeling fracture energy are built up and also verified by test results. Further, this paper shows how to use the interface peeling fracture energy calibrated from the present dowel tests for the practical design of spalling prevention, which is now becoming a popular application of FRP sheets for the maintenance and repair of existing concrete structures in Japan. [ABSTRACT FROM AUTHOR]

A new analytical method for defining the nonlinear bond stress–slip models of fiber reinforced plastics (FRP) sheet–concrete interfaces through pullout bond test is proposed. With this method, it is not necessary to attach many strain gauges on the FRP sheets for obtaining the strain distributions in FRP as well as the local bond stresses and slips. Instead, the local interfacial bond stress-slip models can be simply derived from the relationships between the pullout forces and loaded end slips. Based on a series of pullout tests, the bond stress–slip models of FRP sheet–concrete interfaces, in which different FRP stiffness, FRP materials (carbon FRP, aramid FRP, and glass FRP), and adhesives are used, have been derived. Only two parameters, the interfacial fracture energy and interfacial ductility index, which can take into account the effects of all interfacial components, are necessary in these models. Comparisons between analytical results and experimental ones show good accordance, indicating the reliability of the proposed method and the proposed bond stress–slip models. [ABSTRACT FROM AUTHOR]

This paper presents experimental results on the behavior in tension of reinforced concrete members strengthened with carbon fiber sheets (CFS). CFS reduced the crack spacing and brought about good crack width control as well as a significant change in the average bond stress and the average stress of steel reinforcing bars and concrete. The deterioration mechanism of the CFS bond properties near cracks was presented. [ABSTRACT FROM AUTHOR]