• Steel and Composite Structures
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• v.16 no.6
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• pp.577-593
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• 2014

An exact dynamic stiffness method is introduced for investigating the free vibration characteristics of the steel-concrete composite beams consisting of a reinforced concrete slab and a steel beam which are connected by using the stud connectors. The elementary beam theory is used to define the dynamic behaviors of the two beams and the relative transverse deformation of the connectors is included in the formulation. The dynamic stiffness matrix is formulated from the exact analytical solutions of the governing differential equations of the composite beams in undamped free vibration. The application of the derived dynamic stiffness matrix is illustrated to predict the natural frequencies and mode shapes of the steel-concrete composite beams with seven boundary conditions. The present results are compared to the available solutions in the literature whenever possible.

• Natural Product Sciences
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• v.21 no.4
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• pp.227-230
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• 2015

Chemical investigation of the fermentation broth of a Soft Coral-Derived fungus Pestalotiopsis sp., led to the isolation of a new phthalide derivative, pestalotiolide A (1), three known analogues (2, 3 and 4), along with 5'-O-acetyl uridine (5) first isolated as a natural product. The structure of the new compound (1) was established by comprehensive spectroscopic analysis and chemical methods. Compounds 1 - 4 possessed varying degrees of antiviral activities, which was reported for the first time. Compared to the positive control ribavirin ($IC_{50}=418.0{\mu}M$), pestalotiolide A (1) exhibited significant anti-EV71 activity in vitro, with an $IC_{50}$ value of $27.7{\mu}M$. Furthermore, the preliminary structure-activity relationship of antiviral activities was also discussed.

• Journal of Veterinary Science
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• v.21 no.2
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• pp.19.1-19.10
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• 2020

Given that the current Newcastle disease virus (NDV) infection in wild birds poses the threat to poultry, surveillance of Newcastle disease in captive wild birds was carried out in Jilin, China in 2018. Here, an NDV strain obtained from toco toucan was firstly characterized. The results showed that the F gene of the NDV isolate Toucan/China/3/2018 is classified as genotype II in class II. Sequence analysis of the F0 cleavage site was ¹¹³RQGR/L¹¹⁷, which supports the result of the intracerebral pathogenicity index assay indicating classification of the isolate as low-pathogenicity. Experimental infection demonstrated that Toucan/China/3/2018 can effectively replicate and transmit among chickens. To our knowledge, this is the first report on genetically and pathogenically characterizing NDV strain isolated from toucan, which enriches the epidemiological information of NDV in wild birds.

• Journal of Ceramic Processing Research
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• v.19 no.6
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• pp.479-482
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• 2018

Polystyrene superstructure films show faint rainbow color, and this low color saturation limits its wide application. In this paper, polystyrene superstructure films with single bright blue color were prepared by vertical deposition self-assembly method using polystyrene microspheres with average diameter of $310{\pm}10nm$ as raw material. Polystyrene superstructure films were modified by adding nano-carbon powder, and effect of the amount of nano-carbon powde on color performance was studied. The results showed that without addition of nano-carbon powder, the superstructure films showed a faint rainbow color, while with addition of nano-carbon power, the superstructure films exhibited a single bright blue under the same natural light source. Changing the amount of nano-carbon powder addition could adjust color saturation of the film. With increasing the amount of nano-carbon powder addition from 0.008 wt% to 0.01 wt%, color saturation of the superstructure film increased gradually. Further increasing the amount of nano-carbon powder addition to 0.011wt%, color saturation of the superstructure film didn't increase anymore and tended to get dark.

• Nuclear Engineering and Technology
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• v.55 no.6
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• pp.2298-2304
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• 2023

Titanium alloys are expected to become one of the candidate materials for nuclear-powered spacecraft due to their excellent overall performance. Nevertheless, atomistic mechanisms of the defect accumulation and evolution of the materials due to long-term exposure to irradiation remain scarcely understood by far. Here we investigate the heavy irradiation damage in a-titanium with a dose as high as 4.0 canonical displacements per atom (cDPA) using atomistic simulations of Frenkel pair accumulation. Results show that the content of surviving defects increases sharply before 0.04 cDPA and then decreases slowly to stabilize, exhibiting a strong correlation with the system energy. Under the current simulation conditions, the defect clustering fraction may be not directly dependent on the irradiation dose. Compared to vacancies, interstitials are more likely to form clusters, which may further cause the formation of 1/3<1210> interstitial-type dislocation loops extended along the (1010) plane. This study provides an important insight into the understanding of the irradiation damage behaviors for titanium.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.17
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• pp.7245-7249
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• 2014

Glucose regulated protein 78 (GRP78) is usually recognized as a chaperone in the endoplasmic reticulum. However, increasing evidence indicates that GRP78 can be translocated to the cell surface, acting as a signaling receptor for a variety of ligands. Since little is known about the secretion of GRP78 and its role in the progression of colon cancer we here focused on GRP78 from colon cancer cells, and purified GRP78 protein mimicking the secreted GRP78 was able to utilize cell surface GRP78 as its receptor, activating downstream PI3K/Akt and Wnt/${\beta}$-catenin signaling and promote colon cancer cell proliferation. Our study revealed a new mode of action of autocrine GRP78 in cancer progression: secreted GRP78 binds to cell surface GRP78 as its receptor and activates intracellular proliferation signaling.

• Steel and Composite Structures
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• v.34 no.6
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• pp.783-794
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• 2020

Steel-concrete-steel sandwich composite wall is composed of two external steel plates and infilled concrete core. Internal mechanical connectors are used to enhance the composite action between the two materials. In this paper, the compressive behavior of a novel sandwich composite wall was studied. The steel trusses were applied to connect the steel plates to the concrete core. Three short specimens with different truss spacings were tested under compressive loading. The boundary columns were not included. It was found that the failure of walls started from the buckling of steel plates and followed by the crushing of concrete. Global instability was not observed. It was also observed that the truss spacing has great influence on ultimate strength, buckling stress, ductility, strength index, lateral deflection, and strain distribution. Three modern codes were introduced to calculate the capacity of walls. The comparisons between test results and code predictions show that AISC 360 provides significant underestimations while Eurocode 4 and CECS 159 offer overestimated predictions.

• Journal of Computing Science and Engineering
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• v.8 no.1
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• pp.17-24
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• 2014

In this paper, we propose a new implementation of a failure detector. The implementation uses a dual model of heartbeat and interaction. First, the heartbeat model is adopted to shorten the detection time, if the detection process does not receive the heartbeat message in the expected time. The interaction model is then used to check the process further. The expected time is calculated using the exponential smoothing method. Exponential smoothing can be used to estimate the next arrival time not only in the random data, but also in the data of linear trends. It is proven that the new detector in the paper can eventually be a perfect detector.

• Steel and Composite Structures
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• v.42 no.2
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• pp.257-264
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• 2022

The analysis of the progressive collapse resistance of structures is a well-known issue among structural engineers. Large-span reticulated dome structures are commonly utilized in large public buildings, necessitating research into their progressive collapse resistance to assure user safety. The most significant part of improving the structural resilience of reticulated domes is to evaluate their key elements. Based on a stiffness-based evaluation approach, this work offers a calculating procedure for element importance coefficient. For both original and damaged structures, evaluations are carried out using the global stiffness matrix and the determinant. The Kiewitt, Schwedler, and Sunflower reticulated domes are investigated to explore the distribution characteristic of element importance coefficients in the single-layer dome structures. Moreover, the influences of the load levels, load distributions, geometric parameters and topological features are also discussed. The results can be regarded as the initial concept design reference for single-layer reticulated domes.

• Journal of Magnetics
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• v.16 no.2
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• pp.150-156
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• 2011

Magnetoelectric (ME) transducers were originally intended for magnetic field sensors but have recently been used in vibration energy harvesting. In this paper, a new broadband vibration energy harvester has been designed and fabricated to be efficiently applicable over a range of source frequencies, which consists of two cantilever beams, two magnetoelectric (ME) transducers and a magnetic circuit. The effects of the structure parameters, such as the non-linear magnetic forces of the ME transducers and the magnetic field distribution of the magnetic circuit, are analyzed for achieving the optimal vibration energy harvesting performances. A prototype is fabricated and tested, and the experimental results on the performances show that the harvester has bandwidths of 5.6 Hz, and a maximum power of 0.25 mW under an acceleration of 0.2 g (with g = $9.8\;ms^2$).