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The distribution of cholinergic cell bodies and fibers was examined in the mesencephalon and isthmus of Gekko gecko. Distinct groups with prominent labeled cells were observed in the cranial nerve motor nuclei and isthmic nuclei, and weak labeled cell bodies and fibers were observed in the mesencephalic nucleus of the trigeminal nerve and the central nucleus of the torus semicircularis. After discussing the topological relationships within the tectum and isthmus, we unify the nomenclature of the caudal deep mesencephalic nucleus in lizards and the rostral magnocellular nucleus isthmi in turtles that is similar in terms of the preisthmic position, nontopographic connections with the tectum, and the same midbrain origin to the magnocellular preisthmic nucleus in birds, and may be homologous to the superficial cuneiform nucleus in mammals. None of them belong to the cholinergic nucleus isthmi, as the latter has isthmus origin and topographic reciprocal connections with the tectum. We also discuss the origin and intrinsic function of the inner longitudinal tract of the thick ChAT-ir fibers that course through the mesencephalon and diencephalon. We review the subdivisions of the mesencephalon and isthmus of Gekko gecko as revealed by ChAT immunohistochemistry, as well as the limits of the diencephalo-mesencephalic, mesencephalic-isthmo, and isthmo-rhombocephalic by the ChAT-ir cell- and fiber-poor distribution, and discuss the caudal limit of the isthmus. Our research on the subdivisions of the mesencephalon and isthmus in G. gecko as revealed by ChAT immunohistochemistry will serve as the neuroanatomical basis for subsequent relevant studies of Gekko gecko.

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Birds flying collectively is a fascinating phenomenon in nature, which is central in ethological studies. Owing to the difficulty of introducing controlled variables into a natural bird flock, current animal behavior paradigms limit our understanding of collective behavior and mechanism. The recently developed technology of robo-pigeon, which allows behavior regulation over organisms through brain microstimulation, can potentially serve to design the controlled variables. However, it still poses challenges for unrestrained animals outdoors. Here we report the first application of robo-pigeon to the study of collective behavior, illustrating how intact pigeons in a flock interact with a program-controlled robo-pigeon. The controlled variable of direction manipulation introduced by the robo-pigeon may balance their preferred directional choice in the flock. Its effectivity depends on the hierarchical level to which the robo-pigeon belongs. This study suggests that direct manipulation of flight trajectories by a robo-pigeon might be a useful causal tool to study the collective behavior of bird flocks.

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OBJECTIVE: To study the differences in a special region (SR) corresponding to five internal organs between the young and the elderly and to verify the effectiveness of a developed system for objectifying research in colour inspections of Chinese medicine (CICM). METHODS: An image acquisition device imitating daylight to meet the requirement of CICM was designed. Image processing software based on CICM theory was developed. A total of 83 normal people were sampled and assigned to two groups. The first group (Group I) included 30 people with an average age of 24±2, and the second group (Group II) included 53 people with an average age of 74±4. After image processing, the chromaticity of 10 SRs corresponding to five internal organs was calculated. R, G, and B represent the chromaticity of color red, green, and blue, L indicates color brightness, whereas a and b denote red and yellow respectively. The difference between the young and the elderly was analyzed. RESULTS: (1) The chromaticity of each SR corresponding to five organs was obtained. The average R, G, B, L, a, and b of the sample were 194.4, 147.6, 119.3, 65.2, 15.5, and 22.3, respectively. (2) The R, G, B, and L of the young were greater than those of the elderly, but the a and b of the young were less than those of the elderly. (3) A statistically significant difference in each SR was found between the young and the elderly (P <0.05). The total differences for the Lung (Fei), Heart (Xin), Liver (Gan), Spleen (Pi), and Kidney (Shen) were 50% (3/6), 66.7% (4/6), 66.7% (4/6), 83.3% (5/6), and 91.7% (33/36), respectively. However, the Kidney SR had the greatest statistical discrepancy. CONCLUSION: The old Chinese saying that human Kidney deficiency worsens with age was verified by the results. The objectifying system used to examine CICM was effective. Thus, this system may be used as a basis for further research.

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Nafion/multi-walled carbon nanotubes (Nafion/MCNT) and Nafion/tetraethyl orthosilicate (Nafion/TEOS) nanocomposites were prepared and used as starting materials in the fabrication of an ionic polymer metal composite (IPMC). Experimental data show that the Nafion/MCNT-based IPMC exhibited a blocking force that is two times higher than that of bare Nafion-based IPMC. This higher blocking force is due to the stable homogeneous dispersions of multiwalled carbon nanotubes as well as to their improved conductivity. Meanwhile, the Nafion/TEOS-based IPMC generated a blocking force that is more than two times higher than that of bare Nafion-based IPMC because of the induced channels and increased water content. In this paper, a novel Nafion membrane containing a primary Nafion/TEOS layer sandwiched between two outer Nafion/MCNT nanocomposite layers was prepared by consecutive casting of liquid solutions. By using the multilayered Nafion membrane, IPMC was carefully fabricated by electroless plating. In addition, the blocking force, displacement, and electric current of the IPMC were measured on the test apparatus. The multilayered IPMC exhibited a significantly improved blocking force of 6.5 gf as well as a long effective air-operating life time. Finally, this multilayered IPMC was successfully used to actuate the robotic fish.

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Inspired by the setal microstructure found on the gecko's toe-pads, a highly dense array of high-aspect-ratio (HAR) artificial setae has been developed with a novel mold-casting technique using a porous silicon (PSi) template. To overcome the high fluid resistance in the HAR capillary pores, the PSi template surface is modified with a monolayer coating of dimethylsilane. The coating exhibits similar chemical composition and surface energy to the precursor of the poly(dimethylsiloxane) (PDMS) replica. The compatibility between the template and the replica addresses the major challenge of molding HAR microstructures, resulting in high-resolution replicas of artificial PDMS microsetae with complicated geometry resembling a real gecko's setae. The artificial setae are characterized by a mean radius of 1.3 µm, an aspect ratio of 35.1, and a density of ~4.7 × 105 per mm2. Results from adhesion characterizations reveal that with increasing preload, the shear adhesion of micro-setae continually increases while the normal adhesion decreases. The unique adhesion performance is caused by both van der Waals forces and the elastic resistance of PDMS setae. With further structural optimizations and the addition of an actuation mechanism, artificial setal arrays might eventually demonstrate the fascinating adhesion performances of the gecko for mimetic devices such as wall-climbing devices.

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This paper reports the development of a new fabrication process for highly porous and highly functional macroporous silicon (m-PSi). This new fabrication process involves two steps of electrochemical etching and one step of sonication detachment, and it uses silicon nanocrystallites as a template to form a honeycomb-like macroporous structure. The surface fabricated by this process has been characterized in comparison with the m-PSi surface fabricated by a one-step etching process. Scanning electron microscopy (SEM) images show that both m-PSi surfaces have nearly similar pore diameters (1-2 microm), but their porous microstructures are very different: the surface fabricated by two-step etching exhibits a smooth and shallow pore structure, while the other surface exhibits a rough and deep pore structure. Fourier transform infrared spectroscopy (FTIR) analyses reveal that the former is functionalized with a reactive Si-H group, while the latter is functionalized with a stable Si-O-Si group. To evaluate the Si-H reactive group, an allyl polyethylene glycol (PEG) is employed to modify the surface through hydrosilylation. SEM, FTIR, X-ray photoelectron spectroscopy, and water contact angle measurements are used to characterize the PEG-grafted m-PSi surface. PEG-grafted m-PSi substrates may have wide applications in biosensors, chemosensors, and biochips.

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