Fluid viscous dampers are used to control story drifts and member forces in structures during earthquake events. These elements provide satisfactory performance at the design-level or maximum considered earthquake. However, buildings using fluid viscous dampers have not been subjected to very large earthquakes with intensities greater than the design and maximum considered events. Furthermore, an extensive database of viscous damper performance during large seismic events does not exist. To address these issues, a comprehensive analytical and experimental investigation was conducted to determine the performance of damped structures subjected to large earthquakes. A critical component of this research was the development and verification of a detailed viscous damper mathematical model that incorporates limit states. The development of this model and the laboratory and simulation results conclude good correlation with the new model and the damper limit states and provide superior results compared with the typical damper model when considering near collapse evaluation of structures. 1281 Figure 4. Dampers used in the retrofit of a concrete-frame building.Figure 5. Physical parts of a viscous damper.the unit through small orifices. The mechanical construction and orifice properties can be varied to obtain the desirable damper properties. Figure 5 presents a line drawing of viscous dampers, identifying the pertinent components. Following is a description of each component [2].1. Piston rod: Solid 17-4 PH (precipitation hardening) stainless steel, billet machined, through hardened, and then hand-polished to a mirrored finish of less than 100 m (4 in).

Kidney specimens taken from normal humans and patients with various renal diseases were examined by immunofluorescent and immunoelectron microscopy using a monoclonal antibody to the alpha 1 chain of type III collagen. Indirect immunofluorescent staining revealed that intraglomerular localization of type III collagen antigen in 41 of 66 patients, while it was absent from the glomeruli of normal human kidneys. Type III collagen was found within the mesangium of 22 patients with various types of renal diseases, and was distributed in a focal and segmental manner in most of the cases. Mesangial localization of the collagen correlated with the increase in the mesangial matrix. Type III collagen was also present in the vascular pole, crescents (particularly in the organizing phase) and sclerosed glomeruli. Immunoelectron microscopy using pre-embedding and post-embedding techniques confirmed the above observations. These findings indicate that type III collagen participates in mesangial expansion, crescent organization, and glomerulosclerosis.

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The xylanase gene cluster from the rumen anaerobe Prevotella bryantii B 1 4 was found to include a gene (xynR) that encodes a multidomain regulatory protein and is downstream from the xylanase and ␤-xylosidase genes xynA and xynB. Additional genes identified upstream of xynA and xynB include xynD, which encodes an integral membrane protein that has homology with Na:solute symporters; xynE, which is related to the genes encoding acylhydrolases and arylesterases; and xynF, which has homology with the genes encoding ␣-glucuronidases. XynR includes, in a single 833-amino-acid polypeptide, a putative input domain unrelated to other database sequences, a likely transmembrane domain, histidine kinase motifs, response regulator sequences, and a C-terminal AraC-type helix-turn-helix DNA binding domain. Two transcripts (3.7 and 5.8 kb) were detected with a xynA probe, and the start site of the 3.7-kb transcript encoding xynABD was mapped to a position upstream of xynD. The DNA binding domain of XynR was purified after amplification and overexpression in Escherichia coli and was found to bind to a 141-bp DNA fragment from the region immediately upstream of xynD. In vitro transcription assays demonstrated that XynR stimulates transcription of the 3.7-kb transcript. We concluded that XynR acts as a positive regulator that activates expression of xynABD in P. bryantii B 1 4. This is the first regulatory protein that demonstrates significant homology with the two-component regulatory protein superfamily and has been shown to be involved in the regulation of polysaccharidase gene expression.

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Measurements of (p, ρ, T) properties for compressed liquid propane have been obtained by means of a metal-bellows variable volumometer at temperatures from 340 to 400 K at pressures up to 200 MPa. The volumefraction purity of the propane sample was 0.9999. The expanded uncertainties (k = 2) of temperature, pressure, and density measurements have been estimated to be less than 3 mK; 1.5 kPa (p < = 7 MPa), 0.06% (7 MPa

150 MPa); and 0.11%, respectively. Four (p, ρ, T) measurements at the same temperatures and pressures as literature values have been conducted for comparisons. In addition, vapor pressures were measured at temperatures from 280 to 369 K. Furthermore, comparisons of available equations of state with the present measurements are reported.