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This paper presents a structural modeling analysis of transmission towers with varied leg length combinations to examine the structural effects of unequal leg lengths. Power transmission towers in mountainous areas often use unequal leg lengths to accommodate the changing slope of the terrain. In this study, three types of 345 kV steel transmission towers with the D-type bracing system were considered as analytical examples to discuss the internal force distribution of the tower structure subjected to a load under a fully wired condition. Different tower structural types exhibit similar structural characteristics. The upper part of the force distribution of a tower structure is less affected by varied leg length configurations. The central parts affected by unequal leg lengths are the extension part and the tower leg component. Analytical results indicate the critical elements of tower structures with unequal leg lengths, which can serve as a valuable reference for disaster prevention and reduction. In this study, the primary elements of the towers were all under the permissible strength even with the leg length differences exceeding the current specifications. This implies that adjusting the regulation of leg length differences of a transmission tower with unequal leg lengths can serve as the basis for future research, highlighting the advantages of unequal leg length tower applications.

The building mass damper (BMD) design features the use of partial structural mass, instead of additional tuned mass, as an energy absorber. Therefore, it becomes more effective in dynamic response reduction compared to the conventional tuned mass damper (TMD) design with very limited added tuned mass. In this study, an optimum building mass damper (OBMD) design approach, namely optimum dynamic response control approach, based on a simplified 3-lumped-mass structure model is proposed to enhance the seismic performances of both the superstructure (or tuned mass) and substructure (or primary structure) respectively above and below the control layer. A series of shaking table tests on one bare and two OBMD specimens were conducted to experimentally verify the efficacy of the proposed OBMD design approach. To further demonstrate the advantage of the OBMD design conditionally over other passive control approaches, the seismic responses of the same structure model but respectively designed with a mid-story seismic isolation (MSI) system and additional energy dissipation devices are also numerically analyzed and compared. It is found that the OBMD design can reveal a better seismic performance than the energy dissipation design. More importantly, it can have a comparable and even superior seismic performance to the MSI design especially when the structure model has a medium or long period of vibration.

This paper presents an LC voltage-controlled oscillator (VCO) design which utilizes a set of Inversion-MOS (IMOS)-based varactors. The varactor set is switchable by using a transmission gate such that the tuning range can be extended. The proposed VCO is designed, implemented, and fully evaluated on the wafer in 180-nm CMOS technology. The experimental results show that the VCO has a tuning range of 18.6% from 2.15 to 2.59 GHz. The measured FOM T of -185.2 and -183.2dBc/Hz is achieved when the switches are turned on and off, respectively. The VCO core consumes 6. S9mA at the supply voltage of 1.8V, including the bias current of the IMOS-based varactor set.

Summary A new seismic design manner, namely building mass damper (BMD), which is inspired from a combination of mid-story isolation and tuned mass damper design concepts, recently attracts immense attention. It is mainly because that the use of partial structural mass of the building as an energy absorber in the BMD design can overcome the drawback of limited response reduction due to insufficient added tuned mass in the conventional tuned mass damper design. In this study, an optimum BMD (OBMD) design approach, namely optimum dynamic characteristic control approach, based on a simplified 3-lumped-mass structure model is proposed to seismically protect both the superstructure (or tuned mass) and the substructure (or primary structure), respectively, above and below the control layer. A series of sensitivity analyses and experimental studies on different parameters, including mass, frequency, and damping ratios, of a building model designed with a BMD system were conducted. The test results verify the practical feasibility of the BMD concept as well as the effectiveness of the proposed OBMD design. Furthermore, by comparing with the numerical results of a mid-story isolated counterpart, it is demonstrated that the proposed OBMD design can have a comparable and even better control performance.

In recent years, rapid urbanization associated with considerable urban population growth has placed significant demands on urban transport infrastructure. As a result, more and more elevated highways, usually long piers, have been erected in urban platforms to ease urban traffic pressures. However, the high traffic volume of such highway bridges can cause significant vibration. To study the effects of vibration caused by bridge traffic, this study monitored the acceleration due to moving vehicles of an isolated bridge for 24 hours. The fast Fourier transform method and the system implementation method are then used to analyse the acceleration measurements and thus to calibrate the system parameters of the bridge and the building. Besides, the displacement from the deck to the pier and the deck acceleration were measured to investigate how vehicle transport affects the structural performance of the deck and pier. The results can be used as a reference for improving vibration problems caused by bridge traffic in the future.

Functionally diverse T cell populations interact to maintain homeostasis of the immune system. We found that human and mouse antigen-activated T cells with high expression of the lymphocyte surface marker CD52 suppressed other T cells. CD52(hi)CD4(+) T cells were distinct from CD4(+)CD25(+)Foxp3(+) regulatory T cells. Their suppression was mediated by soluble CD52 released by phospholipase C. Soluble CD52 bound to the inhibitory receptor Siglec-10 and impaired phosphorylation of the T cell receptor-associated kinases Lck and Zap70 and T cell activation. Humans with type 1 diabetes had a lower frequency and diminished function of CD52(hi)CD4(+) T cells responsive to the autoantigen GAD65. In diabetes-prone mice of the nonobese diabetic (NOD) strain, transfer of lymphocyte populations depleted of CD52(hi) cells resulted in a substantially accelerated onset of diabetes. Our studies identify a ligand-receptor mechanism of T cell regulation that may protect humans and mice from autoimmune disease.

A hydride-centered dithiophosphate cluster [Cu8(μ4-H){S2P(OEt)2}6](PF6) (1)] previously developed by us was applied as a new catalyst to the 1,3-dipolar cycloaddition of organic azides and alkynes for preparing substituted trizoles. With the required catalyst loading as low as 0.4 mol%, the reactions of terminal alkynes with BnN3 all proceeded smoothly at ambient temperature in CH3CN to exclusively produce 1,4-triazoles in good yields. For these reactions, it is assumed that the formation of the requisite copper acetylide intermediate is facilitated by the abstraction of the terminal hydrogen of alkynes by the hydride released from the central of the cluster. With only few examples being documented in literatures, the reactions of a range of internal alkynes have also been realized under the catalysis of 1 (0.8 mol%) in DMF at elevated temperature, to yield 1,4,5-trisubstituted triazoles in moderate to high yields. Our study has provided a preliminary insight into the effect of sulfur-based ligands on the activity of copper ion.

The discrepancies of dynamic behavior in base-isolated and mid-story isolated buildings are investigated experimentally in this study. In a mid-story isolated building, the isolation system is incorporated into the mid-story rather than the base of the building. The shaking table test results disclose that with the same design of the isolated superstructure and isolation system, a mid-story isolated building has smaller fundamental modal quantities than a base-isolated building. Besides, the seismic response at the superstructure is mainly attributed to the fundamental mode response, while the higher mode responses contribute significantly to the seismic responses at the substructure below the isolation system. Therefore, the modal response spectrum analysis appropriately considering the contribution of higher modes, rather than the equivalent lateral force procedure only considering the fundamental mode, is suggested for the preliminary design of mid-story isolated buildings prior to performing nonlinear responses history analyses.

SUMMARY In a midstory isolated building, the isolation system is incorporated into the midstory rather than the base of the building. Because of the flexibility of the substructure below the isolation system in a midstory isolated building, the contribution of higher modes to the seismic responses of the midstory isolated structure may not be negligible, especially when the coupling of higher modes exists. To investigate this modal coupling effect, a simplified three-lumped-mass structural model of the midstory isolated building is assumed in this study. Through the equivalent linear analysis and shaking table tests, it is found that the coupling of higher modes may lead to enlarged acceleration responses at the super-floor and superstructure above the isolation layer. Accordingly, a simple method to prevent the midstory isolation design from the coupling of higher modes attributed to the improper design of the substructure and superstructure is proposed in this paper. Copyright © 2012 John Wiley & Sons, Ltd.

The formation of a C-N bond via the cross-couplings of aryl iodides with azoles, aryl amine, and amides can be successfully achieved in decent yield by the utilization of both [Cu8(H){S2P(O i Pr)2}6] + and [Cu8{S2P(OEt)2}6] 2+ as the pre-catalysts.

The mid-story isolation design method is recently gaining popularity for the seismic protective design of buildings located in the areas of high population. In a mid-story isolated building, the isolation system is incorporated into the mid-story rather than the base of the building. In this paper, the dynamic characteristics and seismic responses of mid-story isolated buildings are investigated using a simplified three-lumped-mass structural model for which equivalent linear properties are formulated. From the parametric study, it is found that the nominal frequencies of the superstructure and the substructure, respectively, above and below the isolation system have significant influences on the isolation frequency and equivalent damping ratio of a mid-story isolated building. Moreover, the mass and stiffness of the substructure are of greater significance than the superstructure in affecting the dynamic characteristics of the isolated building. Besides, based on the response spectrum analysis, it is noted that the higher mode responses may contribute significantly to the story shear force of the substructure. Consequently, the equivalent lateral force procedure of design codes should carefully include the effects of higher modes. Copyright © 2010 John Wiley & Sons, Ltd.

Genes for peripheral tissue-restricted self-antigens are expressed in thymic and hematopoietic cells. In thymic medullary epithelial cells, self-antigen expression imposes selection on developing autoreactive T cells and regulates susceptibility to autoimmune disease in mouse models. Less is known about the role of self-antigen expression by hematopoietic cells. Here we demonstrate that one of the endocrine self-antigens expressed by human blood myeloid cells, proinsulin, is encoded by an RNA splice variant. The surface expression of immunoreactive proinsulin was significantly decreased after transfection of monocytes with small interfering RNA to proinsulin. Furthermore, analogous to proinsulin transcripts in the thymus, the abundance of the proinsulin RNA splice variant in blood cells corresponded with the length of the variable number of tandem repeats 5′ of the proinsulin gene, known to be associated with type 1 diabetes susceptibility. Self-antigen expression by peripheral myeloid cells extends the umbrella of “immunological self” and, by analogy with the thymus, may be implicated in peripheral immune tolerance.

A 40-year-old Korean man presented with painful swelling and tenderness of both ankle joints as well as the plantar surfaces of both feet, along with inflammatory back pain, and a purulent discharge from the urethral orifice. The patient also complained of sicca-like symptoms including dry eyes and dry mouth. An immunological analysis revealed a high titer of rheumatoid factor, positive results for antinuclear antibody and anti-Ro antibody, and a positive result for HLA-B27. An antibody titer for Chlamydia was also significantly increased. Positive results of the Schirmer’s test and for keratoconjunctivitis sicca were confirmed by an ophthalmologist. These clinical manifestations were compatible with Chlamydia-induced reactive arthritis (ReA) accompanied by Sjogren’s syndrome (SS). This is the first report of the combination of these two distinct disease entities in the Korean population.

Autoantigen-specific regulatory T cells (Treg) are a potential cell therapy for human autoimmune disease, provided they could be generated in adequate numbers and with stable function. To this end, we determined the feasibility of cloning and expanding human CD4 + Treg specific for the type 1 diabetes autoantigens, GAD65 and proinsulin. Blood CD4 + cells stimulated to divide in response to GAD65 (in three healthy individuals) or proinsulin (in one type 1 diabetic) were flow sorted into single cells and cultured on feeder cells in the presence of anti-CD3 monoclonal antibody, IL-2 and IL-4. Clones were expanded over 4–6 weeks and screened for autoantigen-dependent suppression of tetanus toxoid-specific T-cell proliferation. Suppression by Treg clones was then confirmed against autoantigen-specific non-Treg clones. Of a total of 447 clones generated, 98 (21.9%) had autoantigen-dependent suppressor function. Treg clones were anergic but proliferated to autoantigen after addition of IL-2 or in co-culture with stimulated bulk T cells, without loss of suppressor function. Treg clones were stored over liquid N 2 , thawed and further expanded over 12 days, whereupon they exhibited decreased suppressor function. Expansion of Treg clones overall was in the order 10 7 –10 8 -fold. Treg clones were not distinguished by markers of conventional CD4 + CD25 + Treg and suppressed independently of cell–cell contact but not via known soluble suppressor factors. This study demonstrates that autoantigen-specific CD4 + Treg clones with potential application as a cell therapy for autoimmune disease can be generated and expanded from human blood.

The mid-story isolation design method is recently gaining popularity for the seismic protective design of buildings particularly located at highly populated areas. In a mid-story isolated building, the isolation system is incorporated into the midstory rather than the base of the building. In this paper, the dynamic characteristics and seismic responses of mid-story isolated buildings are investigated using a simplified three-lumped-mass structural model for which equivalent linear properties are formulated. It is found that the nominal frequencies of the superstructure and the substructure respectively above and below the isolation system have significant influences on the isolation frequency and equivalent damping ratio of a mid-story isolated building. The mass and stiffness of the substructure are of greater significance than the superstructure in affecting the dynamic characteristics of the isolated building. Moreover, based on the response spectrum analysis, it is noted that the higher mode responses may contribute significantly to the story shear force of the substructure. The adverse effect arising from the coupling of higher modes on the acceleration responses of the superstructure is presented numerically and experimentally. A simple method to guarantee the mid-story isolation design against the modal coupling effect attributed to the improper design of the substructure and superstructure is proposed. Consequently, the equivalent lateral force procedure of design codes should carefully include the effects of higher modes.

Protein induced by vitamin K absence or antagonist-II (PIVKA-II), also known as des-carboxyprothrombin (DCP), can be used as an alternative tool to alpha-fetoprotein (AFP) for surveillance of hepatocellular carcinoma (HCC). The aims of the present study were to compare PIVKA-II levels between the patients with HCC and patients with non-HCC chronic liver disease, to evaluate the correlation of PIVKA-II and AFP in HCC patients, and finally to estimate the optimal cut-off value for PIVKA-II for the diagnosis of HCC with using the receiver operating characteristic (ROC) curve.A total of 227 consecutive patients with HCC (n=42) or chronic liver disease (n=185) were enrolled in this study. HCC was diagnosed histologically or by imaging such as computed tomography, magnetic resonance imaging or angiography. The serum PIVKA-II and AFP levels were measured by electrochemiluminoimmunoassay with using the Haicatch PIVKA-II kit and by immunoradiometric assay, respectively.The PIVKA-II level in the HCC patients was significantly higher than the non-HCC chronic liver disease patients (903.0+/-1156.7 vs. 111.7+/-211.0 mAU/ mL, respectively, P0.01). PIVKA-II and AFP showed a statistical correlation in HCC patients (r=0.46, P0.01). The sensitivity and specificity of PIVKA-II for the diagnosis of HCC were 66.7% and 74.1%, respectively, and when tasted together with AFP, the sensitivity was increased by 85.7%. For the ROC curve of PIVKA-II in HCC patients, the specificity of a 250 mAU/mL level of PIVKA-II was 95%.PIVKA-II was as useful surveillance tool for differentiating HCC from chronic liver disease, and a PIVKA-II value of 250 mAU/ mL was proposed as a significant cut-off value for diagnosis of hepatocellular carcinoma.

Regulatory T cells (Tregs) suppress pro-inflammatory immune responses and prevent autoimmune disease. Many types of Tregs have been described, the prototypic in mice defined as CD4 +CD25 +with high expression of the Foxp3 transcription factor. However, Fox P3 is not a reliable marker of human CD4 +CD25 +Tregs and Tregs activated by disease-associated antigens have not been well characterised. By comparing autoantigen-activated CD4 +T-cell clones, we identified CD52 as a marker of suppressor clones. We then showed that high expression of CD52 on antigen-activated T cells identified a unique Treg population in human blood. CD52hi Tregs were not distinguished by markers of CD4 +CD25 +Tregs and did not require cell contact for suppressor function. Following activation by glutamic acid decarboxylase 65 or proinsulin, pancreatic islet autoantigens in type 1 diabetes, generation of CD4 + CD52hi Tregs was reduced in individuals at high risk for type 1 diabetes. Autoantigen-specific Tregs should allow monitoring of autoimmune disease susceptibility and response to immunotherapy, in addition to being directly applicable as a cell therapy for autoimmune disease.

Sarcoidosis is a rare systemic disorder with unknown cause that is characterized pathologically by non-caseating granuloma. The lung and mediastinal lymph nodes are almost always involved, and most patients experience acute or insidious respiratory symptom. Because sarcoidosis is an interstitial lung disorder involving the alveoli and bronchioles, the most common radiological finding is a reticularnodular lesion with lymphatic distribution. However, cavitation is quite rare. Sarcoidosis is also a major cause of hepatic granuloma in Western countries, accounting for 12% to 30% of cases. In most patients, the course of hepatic sarcoidosis is benign. However, chronic intrahepatic cholestasis or portal hypertension may develop in some patients. We report a case of sarcoidosis with cavitation and hepatic involvement.