Calmodulin-like (CML) genes function in regulating plant responses to different abiotic stresses, such as high salt and drought. Using japonica type rice seedlings ('Nipponbare'), we induced the expression of OsCML4 (Accession No. NM_001057768), which encodes a rice CML protein. Under drought conditions, transgenic plants over-expressing that gene exhibited obviously improved growth performance and higher survival rates than the wild type (WT). Activity by reactive oxygen species (ROS)-scavenging enzymes superoxide dismutase (SOD) and catalase (CAT), as well as proline concentrations, were significantly increased in transgenic plants. Expression by ROS scavenging-related genes APXI and Cat-B and the stress-related gene OsP5CS1 was also enhanced in the transgenics under drought conditions. However, the sensitivity to abscisic acid (ABA) was similar between over-expressing and WT plants. These results suggest that OsCML4 confers drought tolerance partially through ROS-scavenging and also by inducing other stress-related genes in an ABAindependent manner.

This paper reports the development of a new particle model to simulate fabric mechan ical behavior. A particle model of square meshes, which is close to the orthotropic structure of a woven fabric, is used to represent the fabric. In addition to the separation, bending, and shearing springs, a twist spring is introduced into the particle model to simulate the tension/compression, bending, shearing, and twisting behavior of the fabric. The forces and torques acting on the springs are derived according to fundamental elasticity mechanical laws. Experiments of the heart-loop test involving various fabric behaviors are conducted to validate the model. Comparisons between heart loops gener ated by the model and corresponding actual experimental results verify that the model is able to simulate fabric mechanical behavior with satisfactory accuracy. The anisotropy of woven fabric is shown by different heart loops formed by specimens in different direc tions, and is illustrated by the distributions of various inner stresses.

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In the present study, we investigate the effect of the adiabatic temperature rise property of rock-fill concrete (RFC) on the temperature stress and crack resistance of RFC gravity dams. We conducted tests on the adiabatic temperature rise of RFC with a rock-fill ratio of 42%, 49%, and 55%, respectively. Based on the regression analysis of the test data, a calculation model of the adiabatic temperature rise, considering the rock-fill ratio, is developed, and the finite element analysis software ANSYS is employed to simulate the whole process of the temperature and temperature stress fields of a RFC gravity dam. The main findings of the study are as follows: (1) Both the adiabatic temperature rise rate and the final adiabatic temperature rise of RFC are negatively correlated with the rock-fill ratio. (2) The calculation model of the adiabatic temperature rise of RFC is characterized by its high accuracy, which can help predict the adiabatic temperature rise of RFC with different rock-fill ratios. (3) Without any temperature control measures, the maximum temperature stress of RFC generated by the temperature rise of hydration heat in the RFC gravity dam is 0.93 MPa, which meets the standard of temperature stress control. The results of the present study indicate that dam construction with RFC can simplify the measures of temperature control and crack prevention, improve the construction efficiency, and reduce the cost of dam construction.

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