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One of the most common effects in the animated feature film Quantum Quest are the trails that fall behind and twisted around all photon characters, including the hero character Dave (Figure 1). The quantity of shots that required this effect warranted the development of a trailing system. In photography, when an image is taken with moving light sources and a slow shutter speed (long exposure time), light trails occur. Several computer graphics techniques such as 3D motion blur or 2D image filters can be used to produce this effect. However in a stereoscopic feature film like this, traditional 2D image filters may break the illusion of depth. 3D motion blur can yield favorable results, but is limited in its ability to incorporate stylization and other surrealism animation effects. The trailing effect can also be produced by particle systems in commercial animation software but the design process is tedious and time-consuming.

Motion planning is one of the key capabilities for autonomous humanoid robots. Previous researches have focused on weight balancing, collision detection, and gait generation. Most planners either assume that the environment can be simplified to a 2D workspace or assume that the path is given. In this paper, we propose a motion planning system capable of generating both global and local motions for a humanoid robot in a layered or two and half dimensional environment. The planner can generate a gross motion that moves the humanoid vertically as well as horizontally to avoid obstacles in the environments. The gross motion is further realized by a local planner that determines the most efficient footsteps and locomotion over uneven terrain. If the local planner fails, the failure is feedback to the global planner to consider other alternative paths. The implemented humanoid planning system is an interactive tool that can compute collision-free motions for a humanoid robot in an online manner.

Enabling a humanoid robot to move autonomously in a real-life environment presents a challenging problem. Unlike traditional wheeled robots, legged robots such as humanoid robots have advanced abilities of stepping over an object or striding over a deep gap with versatile locomotions. However, only few humanoid researches today have addressed this problem. In this paper, we consider the problem of planning a humanoid robot's motion in a layered environment cluttered with obstacles and deep narrow gaps. We extend the motion planning system for humanoids in our previous work to account for multiple locomotions and striding ability for a humanoid robot. Each locomotion corresponds to a tier in the search space, and the tiers are connected at the locations where motion transitions are possible. According to a humanoid's geometric properties, such as maximal gait size and step height, we propose to apply the closing morphological operator to the workspace bitmap to compute the reachability region for a humanoid with striding ability. Our experiments show that our system is efficient in generating versatile motions for a humanoid to reach its goal in a complex environment.

The association of genetic variation in the IRAK-1 gene with sepsis outcome has been proved. However, few studies have addressed the impact of the IRAK-4 gene variants on sepsis risk. This study aimed to determine whether the polymorphisms in the IRAK-4 gene are associated with susceptibility to and prognosis of severe sepsis in the Chinese Han ethnic population.In this case-control study, 192 patients with severe sepsis hospitalized in the emergency department of Zhongshan Hospital from February 2006 to December 2009 and 192 healthy volunteers were enrolled. Exclusion criteria included metastatic tumors, autoimmune diseases, AIDS or treatment with immunosuppressive drugs. This study was approved by the ethical committee of Zhongshan Hospital, Fudan University. Sepsis patients were divided into a survival group (n=124) and a non-survival group (n=68) according to the 30-day mortality. Primer 3 software was used to design PCR and sequencing primers. Genomic DNA was extracted from peripheral blood mononuclear cells. Seven tagSNPs in IRAK-4 were selected according to the data of the Chinese Han population in Beijing from the Hapmap project and genotyped by direct sequencing. The chi-square test was used to evaluate the differences in genotype and allele frequencies between the two groups.The distributions of all tagSNPs were consistent with Hardy-Weinberg equilibrium. The allele and genotype frequencies of rs4251545 (G/A) were significantly different between the severe sepsis and healthy control groups (P=0.015, P=0.035, respectively). Carriers of the rs4251545A had a higher risk for severe sepsis compared with carriers of the rs4251545G (OR=1.69, 95% CI: 1.10-2.58). The allele and genotype frequencies of all SNPs were not significantly different between the survival group and non-survival group.These findings indicate that the variants in IRAK-4 are significantly associated with susceptibility to severe sepsis in the Chinese Han ethnic population.