Experimental study on the reactivity of aggregate in concrete

The specimens mixed with cement and various crushed minerals (149–74 μm) were cured at 80°C in saturated steam for 28–180 days as the basic study for cement-aggregate reactions. Quartz and feldspars (microcline, albite and anorthite) reacted with the cement paste, whereas hornblende, augite and olivine did not react. Anorthite was the most reactive and the reactivity of quartz, microcline and albite were almost the same as each other. Jennite was formed by cement-quartz reaction and 11 Å tobermorite, CSH (II) and hydrogarnet were formed by cement-anorthite reaction. The compressive strength of the specimens in which aggregates reacted to cement paste increased as the curing time was prolonged.     

Protein expression and enzymatic activities in normal and soft textured Atlantic salmon (Salmo salar) muscle

Soft textured Atlantic salmon is a sporadic and occasionally very severe problem for the farming and processing industries. The firm and soft fillets examined in this work differed in their gelatinase activities, cross-reactivity with anti-ubiquitin and anti-cathepsin L antibodies, as well as in the in-gel α-chymotryptic peptide maps of electrophoretically isolated myosin heavy chain (MHC) bands. The immunodetections of actin, α-actinin, MHC, and the MALDI TOF MS peptide mass fingerprinting of electrophoretically isolated MHCs only showed minor differences between samples. Other analyses revealed merely individual differences. These results seem to indicate a higher level of gelatinase activation, ubiquitination and cathepsin L cross-reacting material in softer muscle. These results would be consistent with a myopathy, but also with what could be expected in the skeletal muscle of healthy salmonid fish during a normal period of hyperplastic growth.     

Toward in vivo imaging of heart disease using a radiolabeled single-chain Fv fragment targeting tenascin-C

Antibodies specific to a particular target molecule can be used as analytical reagents, not only for in vitro immunoassays but also for noninvasive in vivo imaging, e.g., immunoscintigraphies. In the latter case, it is important to reduce the size of antibody molecules in order to achieve suitable in vivo "diagnostic kinetics" and generate higher-resolution images. For these purposes, single-chain Fv fragments (scFvs; M(r) < 30 kDa) have greater potential than intact immunoglobulins (~150 kDa) or Fab (or Fab') fragments (~50 kDa). Our recent observation of enhanced tenascin-C (Tnc) expression at sites of cardiac repair after myocardial infarction prompted us to develop a radiolabeled scFv against Tnc for in vivo imaging of heart disease. We cloned the genes encoding the heavy and light chain variable domains of the mouse anti-Tnc monoclonal antibody 4F10, and combined them to create a single gene. The resulting scFv-4F10 gene was expressed in E. coli cells to produce soluble scFv proteins. scFv-4F10 has an affinity for Tnc (K(a) = 3.5 × 10(7) M(-1)), similar to the Fab fragment of antibody 4F10 (K(a) = 1.3 × 10(7) M(-1)) and high enough to be of practical use. A cysteine residue was then added to the C-terminus to achieve site-specific (111)In labeling via a chelating group. The resulting (111)In-labeled scFv was administered to a rat model of acute myocardial infarction. Biodistribution and quantitative autoradiographic studies indicated higher uptake of the radioactivity at the infarcted myocardium than the noninfarcted one. Single photon emission computed tomography (SPECT) provided in vivo cardiac images that coincided with the ex vivo observations. Our results will promote advances in diagnostic strategies for heart disease.     

System Identification of Base-Isolated Building using Seismic Response Data

Due to the complex nature of the excitation, and the inherent dynamics characteristics of restoring force of the base isolation systems, the response of base-isolated structures subject to strong earthquakes often experiences excursion into the inelastic range. Therefore, in designing base-isolated structures, the nonlinear hysteretic restoring force model of the base isolation system is frequently used to predict structural response and to evaluate structural safety. In this paper, the prediction error method system identification technique is used in conjunction with nonlinear state-space models for identification of a base-isolated structure. Using a variety of nonlinear restoring force models and bidirectional recorded seismic responses, several identification runs are conducted to evaluate the accuracy of the selected models. Several nonlinear restoring force models are utilized for the base-isolation system, including a multiple shear spring (MSS) model. Among all models used, results indicate that the trilinear hysteretic MSS model closely matches the actual hysteretic restoring force profile and time histories obtained directly from the observed data.     

Vasorelaxant action of Ki1769, a new pyridinecarboximidamide, in isolated porcine coronary artery

The characteristics of KRN2391 (N-cyano-N'-(2-nitroxyethyl)-3-pyridinecarboximidamide monomethansulfonate) and its phenethyl and 2-hydroxyethyl derivatives (Ki1769 and Ki3315) were studied in isolated porcine coronary arteries. KRN2391, Ki1769 and Ki3315 produced concentration-dependent relaxation of coronary arteries contracted by 25 mM KCl and the order of relaxant potency was KRN2391 > Ki1769 > Ki3315. At the maximum effect, KRN2391 produced nearly complete relaxation but Ki1769 produced about 66% relaxation. The maximum effect of Ki3315 could not be obtained because of its solubility. The relaxation induced by KRN2391 was antagonized by glibenclamide and methylene blue but relaxations caused by Ki1769 and Ki3315 were antagonized by glibenclamide alone. The antagonistic effect of glibenclamide on Ki1769- and Ki3315-induced relaxations was more potent than that on KRN2391-induced relaxation. KRN2391 induced relaxation of coronary arteries contracted by 40 mM KCl in a concentration-dependent manner but the effect of KRN2391 was smaller against 40 mM KCl-induced contractions than against 25 mM KCl-induced contractions. Ki1769 had almost no effect on coronary arteries contracted by 40 mM KCl. These results suggest that pyridinecarboximidamide derivatives which do not possess a nitroxyl group have vasodilating ability based on a K+ channel opening action.     

Spectral unmixing model to assess land cover fractions in Mongolian steppe regions

The land cover fractions (LCFs) and spectral reflectance of photosynthetic vegetation (PV), nonphotosynthetic vegetation (NPV), and bare soil were measured at 58 sites in semi-arid and arid regions of Mongolia in the summers of 2005 and 2006. These data sets allowed a detailed assessment of the impact of measurement geometry as represented by the solar zenith angle θ_s, sensor view zenith angle θ_v and azimuth view angle ? in the estimation of LCF values by means of the spectral unmixing model (SUM). The bidirectional distribution function (BRDF) was fitted to the reflectance data and then used to produce reflectance at various measurement geometries. LCFs from these reflectance data for a given combination of θ_s, θ_v, and ? were compared with visually determined LCFs. It was found that θ_s in the range of 30-45° produced a better agreement of LCFs. For θ_v, the agreement is not very sensitive to the choice of angle for the range 30-70°, although θ_v = 50° showed a slightly better performance. The azimuth view angle does not have strong influences to the LCF estimation, except for the case of ? = 180° (view toward the sun), which does not allow precise fitting of BRDF function over a tall vegetation site. Overall, this study verified the results of earlier studies obtained mostly for the American continents that SUM is capable of producing LCF estimates accurately and also found that its accuracy was, in general, much better than that by the more traditional approach of the supervised classification method (SCM) applied to images of a digital camera.     

Adult moyamoya disease progressing from unilateral to bilateral involvement

The effect of domestically-manufactured excimer laser with adjunctive balloon angioplasty in achieving revascularization and reduction of residual stenosis was assessed. 20 femoral arteries with thrombosis and occlusion from 12 dogs were subject to angiography. At first excimer laser angioplasty was done followed by balloon angioplasty. The diameter and residual stenosis of revascularized vessel were measured. The result showed that 17 out of 20 vessels (85%) were revascularized. The diameter of revascularized vessel by excimer laser were 1.22 +/- 0.14 mm, while residual stenoses were 54% +/- 5%. After adjunctive balloon angioplasty the diameter and residual stenoses were 2.04 +/- 0.16 mm and 20% +/- 7% respectively (P < 0.05 and P < 0.01). Complication in form of vasoperforation occurred in 3/20 vessels (15%). It is concluded that China- manufactured excimer laser angioplasty is effective when used for revascularization. While the reduction of narrowing and residual stenoses was enhanced after adjunction of balloon angioplasty. This method can be employed in treating peripheral occlusive disease effectively and safely.     

A Mathematical Model of Perception with Reference to Peripheral Vision and its Application to the Hermann Grid Illusion

Central vision and peripheral vision are two of main components of visual perception. The functional differences between the two visions are considered with two points of view: the physiological receptive field and the psychological perceptive field.

The authors propose a retinal model of lateral inhibition. The output is discrete summation of ganglion cell responses through the Difference of Gaussian (DOG) function of the coupling width. The coupling width is given by the size of receptive field, according to Fisher’s findings that the distribution of the ganglion cell density decreases from the fovea to the peripheral area. Sampling points of the summation correspond to the positions of the ganglion cells, so that a number of points in all the same in each receptive field. The coupling width was determined by the data of Jung and Spillmann’s (1970) psychological experiment. As an application of this model, the Hermann grid illusion is quantitatively explained.