Search

Ludian Earthquake (Ms6.5, Mw6.1) on August 3, 2014 has induced many new slope failures, and resulted in more than 600 deaths and significant property losses. The seismogenic fault is a left-lateral strike-slip hidden fault, an extension of NW–SE Baogunao-Xiaohe Fault. 235 landslides induced by the earthquake have been interpreted by field investigation and remote sensing. The high-susceptibility ranges of different effective factors to the landslides are examined by the index of the ratio of occurrence probabilities. Unlike other earthquake events such as the Wenchuan earthquake in 2008, most of the landslides are located in the footwall, and their spatial arrangement is controlled by the NE oriented main fault of Zhaotong-Ludian, not by the NW seismogenic fault. Four large-scale landslides very closed to the seismogenic fault are described in details. The sliding direction of the four landslides is influenced strongly by the fault properties and the aspect of free face, and there are two principal directions for the large landslides.

Objective To evaluate the diagnostic value of 64-slice spiral CT angiography (CTA) in multiple intracranial aneurysms (MIA). Methods Twenty-five patients (9 males and 16 females, aged from 17 to 68 years) with suspected MIA underwent 64-slice spiral CTA with slice thickness of 0.625mm. The data of all patients were reconstructed with multiplanar reconstruction (MPR), 3-dimensional shade surface display (3-SSD), volume rendering (VR) and maximum intensity projection (MIP). The clinical diagnostic value was evaluated with the results of surgery or interventional embolization therapy. Results A total of 61 aneurysms were detected by 64-slice spiral CTA in 25 patients, among them 17 patients were with 2 aneurysms, 6 patients with 3 aneurysms, 1 patient with 4 aneurysms and 1 patient with 5 aneurysms. The 64-slice spiral CTA could not only clearly demonstrate MIA, but also the size, neck, axis point and parent artery of each aneurysm, and the spatial relationship between aneurysm and the adjacent vessels and bone structures. Twenty-one patients underwent microsurgery and four underwent embolization, the location, size and shape of aneurysm and its spatial relationship with adjacent structures were in accordance with the findings of 64-slice spiral CTA. Conclusion The 64-slice spiral CTA could be used as the first choice in the diagnosis of MIA for its high accuracy, and may be an important adjunct to digital subtraction angiography (DSA) in MIA treatment.

A long-period grating (LPG) based compact optical fiber sensor working in reflection mode is demonstrated. A technique to make a mirror on the cladding region of a fiber end-face to reflect only the cladding modes was realized by growing a polymeric microtip on the core region of the fiber end-face, by photopolymerization, followed by coating the fiber end-face with an aluminum film. Using the cladding-mode-selective fiber end-face mirror, the transmission spectrum of the LPG was "inverted" and reflected. Preliminary results of using the sensor to measure the refractive index of glycerol/water solutions were successfully demonstrated.