Modeling of RC shear walls using shear spring and fiber elements for seismic performance assessment

Reinforced concrete shear wall is one of the most effective members during severe lateral loads especially in earthquakes and winds. Extensive researches, both analytical and experimental, have been carried out to study the behavior of reinforced concrete (RC) shear walls. Predicting inelastic response of RC walls and wall systems requires accurate, effective, and robust analytical model that incorporate important material characteristics and behavioral response features. In this study, a modeling method using fiber and spring elements is developed to capture inelastic responses of an RC shear wall. The fiber elements and the spring reflect flexural and shear behaviors of the shear wall, respectively. The fiber elements are built by inputting section data and material properties. The parameters of the shear spring that represent strength and stiffness degradation, pinching, and slip are determined based on analysis results from a detailed finite element method (FEM) model. The reliability of the FEM analysis program is verified. The applicability of the proposed modeling method is investigated by performing inelastic dynamic analyses for reference buildings with various aspect ratios of shear walls

Modeling of RC shear walls using shear spring and fiber elements for seismic performance assessment

Reinforced concrete shear wall is one of the most effective members during severe lateral loads especially in earthquakes and winds. Extensive researches, both analytical and experimental, have been carried out to study the behavior of reinforced concrete (RC) shear walls. Predicting inelastic response of RC walls and wall systems requires accurate, effective, and robust analytical model that incorporate important material characteristics and behavioral response features. In this study, a modeling method using fiber and spring elements is developed to capture inelastic responses of an RC shear wall. The fiber elements and the spring reflect flexural and shear behaviors of the shear wall, respectively. The fiber elements are built by inputting section data and material properties. The parameters of the shear spring that represent strength and stiffness degradation, pinching, and slip are determined based on analysis results from a detailed finite element method (FEM) model. The reliability of the FEM analysis program is verified. The applicability of the proposed modeling method is investigated by performing inelastic dynamic analyses for reference buildings with various aspect ratios of shear walls

A rare case of primary malignant small cell carcinoma combined with urothelial cell carcinoma in the ureter

BACKGROUND: Extrapulmonary small cell carcinomas have been reported in a variety of organs, and their incidence in the genitourinary tract is second only to that in the gastrointestinal tract. To date, however, only a few cases of small cell carcinoma of the ureter have been reported. Because the extreme rarity of this type of carcinoma, its clinical behaviour, diagnostic methods, and effective treatment modalities have not yet been determined. CASE PRESENTATION: A 59-year-old man presented with a 1-month history of painless gross haematuria. Urine cytopathology revealed a urothelial carcinoma and computed tomography revealed left hydronephroureterosis with a distal ureteral stone and a mildly enhanced fungating mass just below the stone-impacted site. The preoperative TNM stage was T2N0M0. The patient underwent simultaneous diagnostic ureterorenoscopy and left laparoscopic nephroureterectomy with bladder cuff resection. Gross examination showed a 3.5 × 3.0 × 0.8 cm white, partly yellow mass in the left distal ureter. Light microscopy showed a small cell carcinoma, overlaid on a urothelial carcinoma in situ, invading the ureter and external lateral resection margins. The small cell carcinoma was diffusely positive for neuron-specific enolase, and exhibited focal positivity for CD 56, synaptophysin, chromogranin and cytokeratin 20. The patient was treated with adjuvant chemotherapy, consisting of cisplatin and etoposide, and radiation therapy, and has been well, without evidence of tumour recurrence or metastasis in the 10 months after surgery. CONCLUSION: Small cell carcinoma of the ureter is rare. Although its clinical behaviour and diagnostic modalities have not been determined and it has yet to be diagnosed immunohistopathologically, multimodality treatment including surgery, chemotherapy and radiotherapy may improve patient survival

High-Resolution 3D Printing of Freeform, Transparent Displays in Ambient Air

Direct 3D printing technologies to produce 3D optoelectronic architectures have been explored extensively over the last several years. Although commercially available 3D printing techniques are useful for many applications, their limits in printable materials, printing resolutions, or processing temperatures are significant challenges for structural optoelectronics in achieving fully 3D-printed devices on 3D mechanical frames. Herein, the production of active optoelectronic devices with various form factors using a hybrid 3D printing process in ambient air is reported. This hybrid 3D printing system, which combines digital light processing for printing 3D mechanical architectures and a successive electrohydrodynamic jet for directly printing transparent pixels of organic light-emitting diodes at room temperature, can create high-resolution, transparent displays embedded inside arbitrarily shaped, 3D architectures in air. Also, the demonstration of a 3D-printed, eyeglass-type display for a wireless, augmented reality system is an example of another application. These results represent substantial progress in the development of next-generation, freeform optoelectronics

Growth of ultra-uniform graphene using a Ni/W bilayer metal catalyst

We investigated a bilayer catalyst system consisting of polycrystalline Ni and W films for growing mono-layer graphene over large areas. Highly uniform graphene was grown on Ni/W bilayer film with 100% coverage. The graphene grown on Ni/W bilayer film and transferred onto an insulating substrate exhibited average hole and electron mobilities of 727 and 340 cm(2)V(-1)s(-1), respectively. A probable growth mechanism is proposed based on X-ray diffractometry and transmission electron microscopy, which suggests that the reaction between diffused carbon and tungsten atoms results in formation of tungsten carbides. This reaction allows the control of carbon precipitation and prevents the growth of non-uniform multilayer graphene on the Ni surface; this has not been straightforwardly achieved before. These results could be of importance in better understanding mono-layer graphene growth, and suggest a facile fabrication route for electronic applications. (C) 2015 AIP Publishing LLCopen0

Sorbus alnifolia protects dopaminergic neurodegeneration in Caenorhabditis elegans

Context: The twigs of Sorbus alnifolia (Sieb. et Zucc.) K. Koch (Rosaceae) have been used to treat neuro- logical disorders as a traditional medicine in Korea. However, there are limited data describing the efficacy of S. alnifolia in Parkinson’s disease (PD). Objective: This study was conducted to identify the protective effects of the methanol extracts of S. alnifolia (MESA) on the dopaminergic (DA) neurodegeneration in Caenorhabditis elegans. Materials and methods: To test the neuroprotective action of MESA, viability assay was performed after 48 h exposure to 1-methyl-4-phenylpyridine (MMPþ) in PC12 cells and C. elegans (400 lM and 2 mM of MMPþ, respectively). Fluorescence intensity was quantified using transgenic mutants such as BZ555 (Pdat-1::GFP) and and UA57 (Pdat-1::GFP and Pdat-1::CAT-2) to determine MESA’s effects on DA neurode- generation in C. elegans. Aggregation of a-synuclein was observed using NL5901 strain (unc-54p::a- synuclein::YFP). MESA’s protective effects on the DA neuronal functions were examined by food-sensing assay. Lifespan assay was conducted to test the effects of MESA on the longevity. Results: MESA restored MPPþ-induced loss of viability in both PC12 cells and C. elegans (85.8% and 54.9%, respectively). In C. elegans, MESA provided protection against chemically and genetically-induced DA neurodegeneration, respectively. Moreover, food-sensing functions were increased 58.4% by MESA in the DA neuron degraded worms. MESA also prolonged the average lifespan by 25.6%. However, MESA failed to alter a-synuclein aggregation. Discussion and conclusions: These results revealed that MESA protects DA neurodegeneration and recov- ers diminished DA neuronal functions, thereby can be a valuable candidate for the treatment of PD