Deterministic full-scenario analysis for maximum credible earthquake hazards.

Great earthquakes are one of the major threats to modern society due to their great destructive power and unpredictability. The maximum credible earthquake (MCE) for a specific fault, i.e., the largest magnitude earthquake that may occur there, has numerous potential scenarios with different source processes, making the future seismic hazard highly uncertain. We propose a full-scenario analysis method to evaluate the MCE hazards with deterministic broadband simulations of numerous scenarios. The full-scenario analysis is achieved by considering all uncertainties of potential future earthquakes with sufficient scenarios. Here we show an application of this method in the seismic hazard analysis for the Xiluodu dam in China by simulating 22,000,000 MCE scenarios in 0-10 Hz. The proposed method can provide arbitrary intensity measures, ground-motion time series, and spatial ground-motion fields for all hazard levels, which enables more realistic and accurate MCE hazard evaluations, and thus has great application potential in earthquake engineering.

Rational design of a thermophilic ß-mannanase fromBacillus subtilis TJ-102 to improve its thermostability.

A rational design method to improve ß-mannanase (ManTJ102) thermostability was developed successfully in this study. The flexible area of residues 330-340 in ManTJ102 was firstly selected from analysis of molecular dynamics simulation and then the critical amino acid residue (Ala336Pro) with the lowest mutation energy was determined by virtual mutation, whose mutant was named as Mutant336. Afterward, the dynamics transition temperature (Tdtt) of ManTJ102 and Mutant336 was evaluated by simulated annealing and heating, and Mutant336 with higher Tdtt was implemented for experimental verification of the enzyme thermostability. As a result, the half-life of Mutant336 activity was 120 min at 60 °C, which was 24-fold of ManTJ102, and the irreversible thermal denaturation constant of Mutant336 was only about 2/5 of ManTJ102, indicating that Mutant336 has better thermostability than ManTJ102. Furthermore, Mutant336 has much higher ß-mannanase activity and specific activity than ManTJ102. Therefore, Mutant336 was more suitable to further research for applications.

Feasibility of quantitative parameters of dynamically enhanced patterns of spiral computed tomography scanning integrated into tumour progression before targeted treatment of non-small cell lung cancer.

INTRODUCTION: The relationship between quantitative parameters of contrast-enhanced computed tomography (CT) and non-small cell lung cancer (NSCLC) progression remains controversial. We aimed to explore the usefulness of contrast-enhanced spiral CT scanning for confirming the time of tumour progression before targeted treatment of NSCLC. METHODS: Contrast-enhanced spiral CT scanning was performed on 33 NSCLC patients with a biopsy-proven diagnosis of NSCLC. All the patients were divided into three groups according to times of tumour progression (<6 weeks, 6-20 weeks, and >20 weeks). The perfusion CT data were used to calculate quantitative parameters, including enhanced peak values, peak time of tumour enhancement, ratio of tumour mass and enhanced aorta peak value and perfusion value of blood flow. Variance analysis was used for statistical analysis among the three groups using SAS 9.13 statistical software. RESULTS: Tumour perfusion values among the three group with different stage of TTP were significantly different from each other with P = 0.0129 (<6 weeks, perfusion value = 0.35 ± 0.15 mL/(min × mL); 6-20 weeks, perfusion value = 0.41 ± 0.086 mL/(min × mL); > 20 weeks, perfusion value = 0.47 ± 0.087 mL/(min × mL)). However, no significant differences were found in other parameters (enhanced peak values, peak time of tumour enhancement, ratios of tumour mass, and enhanced aorta peak value) among three groups (P > 0.05). CONCLUSION: The NSCLC patients with high perfusion value before targeted therapy are more sensitive to targeted therapy, and further experiments with larger sample size are needed.