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By using a lead-free AgBi-based scheme, we successfully synthesized a two-dimensional double perovskite ferroelastic (DPA)4AgBiBr8 with high Tc of 375 K and a narrow band gap of 2.44 eV, where DPA is 2,2-dimethylpropan-1-aminium.

Two-dimensional (2D) hybrid double perovskites have attracted extensive research interest for their fascinating physical properties, such as ferroelectricity, X-ray detection, light response and so on. In addition, ferroelastics, as an important branch of ferroic materials, exhibits wide prospects in mechanical switches, shape memory and templating electronic nanostructures. Here, we designed a 2D phase-transition double perovskite ferroelastic through a structurally progressive strategy. This evolution is core to our construction process from 0D to 1D and AgBi-based 2D. In this way, we successfully synthesized 2D lead-free ferroelastic (DPA)

The potential market of service and entertainment humanoid robots has attracted a great amount of research interests in the recent years. Several models of humanoid robots have been designed in research projects. However, it remains a great challenge to make humanoid robots move autonomously. Motion planning is one of the key capabilities that an autonomous robot should have. An autonomous robot should be able to accept highlevel commands and move in a real-life environment without colliding with environmental obstacles. A high-level command is something like “Move to location A on the second floor” while the robot is currently at some location B on the first floor, for example. It is an interesting problem for humanoid robots since locomotion capability possessed by a humanoid robot is usually much better than a mobile robot. Like a human, a humanoid robot should be able to step upstairs or downstairs and stride over small obstacles or a narrow deep gap in a complex environment such as the one shown in Fig. 1. Similar needs for the planning capability also arise in the domain of computer animation in generating motions for autonomous characters. The motion for a humanoid robot to achieve a given goal is typically very complex because of the degrees of freedom involved and the contact constraint that needs to be maintained. Therefore, it is common to take a two-level planning approach to solve this problem. In our previous work (Li et al, 2003), we have been able to plan efficient humanoid walking motions in a layered environment. The approach used in the planner decomposed the planning problem into subproblems of global and local planning, each of which is easier to solve. The global planner assumes some basic properties of a humanoid and uses an approximated geometric shape to define the path planning problem. The path generated by the global planner is then passed to the local planner to realize the path with appropriate walk motions. However, in previous work, the locomotion of a humanoid is usually limited to forward walking only, and a humanoid cannot pass a deep gap even if it can stride over it. In this chapter, we will describe a motion planning system adopting the two-level approach and extending the work to overcome the above two limitations. We will present an efficient implementation of the planner in terms of space and time such that it can be used in an on-line manner. The rest of the chapter will be organized as follows. In the next section, we will review the researches pertaining to our work. In the third section, we will give a formal description of the problem we consider in this chapter. We will then propose the planning algorithm in the

Neuregulin 1 (Nrg1) is involved in multiple biological processes in the nervous system. The present study investigated changes in Nrg1 signaling in the major brain regions of mice subjected to lipopolysaccharide (LPS)-induced neuroinflammation. At 24 h post-intraperitoneal injection of LPS, mouse brain tissues, including tissues from the cortex, striatum, hippocampus and hypothalamus, were collected. Reverse transcription-polymerase chain reaction was used to determine the expression of Nrg1 and its receptors, Neu and ErbB4, at the mRNA level. Western blotting was performed to determine the levels of these proteins and the protein levels of phosphorylated extracellular signal-regulated kinases (Erk)1/2 and Akt1. Immunohistochemical staining was utilized to detect the levels of pNeu and pErbB4 in these regions. LPS successfully induced sites of neuroinflammation in these regions, in which changes in Nrg1, Neu and ErbB4 at the mRNA and protein levels were identified compared with controls. LPS induced a reduction in pNeu and pErbB4 in the striatum and hypothalamus, although marginally increased pErbB4 levels were found in the hippocampus. LPS increased the overall phosphorylation of Src but this effect was reduced in the hypothalamus. Moreover, increased phosphorylation of Akt1 was found in the striatum and hippocampus. These data suggest diverse roles for Nrg1 signaling in these regions during the process of neuroinflammation.

While producing an animation, we often rely on the artist to make it manually, or sometimes we generate the animation by some physical simulations. However, the animation we created by these methods always has fixed length and is very difficult to reuse. For 3D animation production, in practice, we always need some animations with variable lengths, for example, we would like to place some flags waving in the wind as part of the background, also perhaps nearby some trees standing with their swaying branches. It will be significantly time-consuming and inefficient to make fixed-length animations (flags and trees) for a specified scene every time when the scene is altered. Consequently, suppose we have produced a segment of an animation, then based on some analysis of it, we could randomly generating a new animation, which length is specified as user’s pleases. For example, we could generate an animation which shows a square surrounding by tens of flags swinging differently by using only one short flag animation originally. By doing this, the time for making films could considerably be saved. In this paper, we transform the input animation into a medium called motion texture, which could be used to generate random-length animations. A motion texture records lots of parts of an animation and the relations between these segments. According to the information, we could generate a large amount of different animations we require in the future.

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.

Introduction: Deregulated or excessive host immune responses contribute to the pathogenesis of sepsis. Toll-like receptor (TLR) signaling pathways and their negative regulators play a pivotal role in the modulation of host immune responses and the development of sepsis. The objective of this study was to investigate the association of variants in the TLR signaling pathway genes and their negative regulator genes with susceptibility to sepsis in the Chinese Han population. Methods: Patients with severe sepsis (n = 378) and healthy control subjects (n = 390) were enrolled. Five genes, namely TLR2, TLR4, TLR9, MyD88 and TOLLIP, were investigated for their association with sepsis susceptibility by a tag single nucleotide polymorphism (SNP) strategy. Twelve tag SNPs were selected based on the data of Chinese Han in Beijing from the HapMap project and genotyped by direct sequencing. The mRNA expression levels of TOLLIP were determined using real-time quantitative Polymerase Chain Reaction (PCR) assays, and concentrations of tumor necrosis factor alpha (TNF-a) and interleukin-6 (IL-6) were measured by enzyme-linked immunosorbent assay (ELISA). Results: Our results showed that the minor C-allele of rs5743867 in TOLLIP was significantly associated with the decreased risk of sepsis (Padj = 0.00062, odds ratio (OR)adj = 0.71, 95% confidence interval (CI) 0.59 to 0.86) after adjustment for covariates in multiple logistic regression analysis. A 3-SNP haplotype block harboring the associated SNP rs5743867 also displayed strong association with omnibus test P value of 0.00049. Haplotype GTC showed a protective role against sepsis (Padj = 0.0012), while haplotype GCT showed an increased risk for sepsis (Padj = 0.00092). After exposure to lipopolysaccharide (LPS), TOLLIP mRNA expression levels in peripheral blood mononuclear cells (PBMCs) from homozygotes for the rs5743867C allele were significantly higher than in heterozygotes and homozygotes for the rs5743867T allele (P = 0.013 and P = 0.01, respectively). Moreover, the concentrations of TNF-a and IL-6 in culture supernatants were significantly lower in the subjects of rs5743867CC genotype than in CT and TT genotype subjects (P = 0.016 and P = 0.003 for TNF-a; P = 0.01 and P = 0.002 for IL-6, respectively). Conclusions: Our findings indicated that the variants in TOLLIP were significantly associated with sepsis susceptibility in the Chinese Han population.