The first internal transcribed spacer (ITS-1) of nuclear ribosomal DNA and mitochondrial DNA 16S rRNA were amplified by Polymerase chain reaction (PCR) using genomic DNA extracted from adult tissue of four species of Scylla spp. and the first zoeal stages of S. serrata, S. paramamosain and S. olivacea as template. Using the ITS-1 region, variation in product fragment length was found to be useful for distinguishing S. serrata and S. olivacea from two other species. The other two species (S. paramamosain and S. tranquebarica) could be identified using the restriction endonuclease Hha I. Using 16S rDNA, all four species were identified using PCR-restriction fragment length polymorphism (RFLP) by double digestion with DraI and HindIII. These genetic markers can be used for hybridization breeding studies and in field studies of larval and juvenile mud crabs of the genus Scylla.

$\text{Pb}\left({\text{Zr}}_x{\text{Ti}}_{1-x}\right){\text{O}}_3$ [PZT] thin films of thickness $2.0\mu \text{m}$ were fabricated on silicon substrates (111)Pt/Ti/${\text{SiO}}_2$ /Si using a sol-gel spin-coating technique. PZT films on substrates with a strontium titanate bottom layer are preferentially {110}-oriented with a columnar structure. The PZT films exhibit good dielectric properties with a dielectric permittivity, ${\epsilon }_r=1545$ and dielectric loss, tan $\delta =0.04$ . Excellent piezoelectric characteristics are also exhibited by the {110}-oriented films with an average effective transverse piezocoefficient, $e_{31}^{\ast }$ of $-8.4\text{C}/{\text{m}}^2$ . The influence of film texture and composition on the transverse piezocoefficient have also been studied.

In recent years, the demand for power generation capacity has increased considerably due to the electric drive of air conditioners and so on in the engines of civil aircraft. Therefore, it is estimated that power losses may increase in the gearbox because of generators and pumps that in turn augment fuel consumption. To understand the phenomena of losses in the gearbox and to reduce these losses, Computational Fluid Dynamics (CFD) simulation that analyzes oil churning loss and windage loss was developed and improvements were made to the shroud of bevel gears. The CFD agreed with experimental results on a bevel gearbox of a 100-seater aircraft. And, it was shown that the suppression of momentum transfer from the rotating gears to oil clusters is of importance. In addition, it was revealed that the loss was reduced up to 36% compared to non-shrouded gears by shrouding in the experiments. This CFD simulation can be applied to many types of gearboxes that have spur gears, bearings and seals.

Genetic diversity and population structure in the fiddler crab Austruca perplexa were investigated to acquire a better understanding of the evolutionary history of the species. Nucleotide sequence analysis was performed from a polymerase chain reaction-amplified fragment of the mitochondrial DNA control region. A 691 bp nucleotide sequence was obtained from 618 specimens collected from 13 sites across Japan, Taiwan, the Philippines, Indonesia and Australia. Haplotype diversity ranged from 0.8 to 0.99, and nucleotide diversity values were lower (range, 0.30–1.9%) than those reported previously for other crustacean taxa. Gene flow was evident within populations in Japan and western Indonesia, but absent among all other populations, including eastern Indonesia. This pattern conforms to the one observed in many other marine taxa across the major biogeographical region referred to as Wallacea. The population pairwise fixation index (FST) and FSTP-values were high and significant among many sites, implying that gene flow is restricted among most of the geographical regions sampled here. We hypothesize that physical oceanic barriers coupled with a short pelagic larval duration are responsible for creating the patterns we found. Strong evidence for population structure in a species that has relatively high dispersal potential, resulting in among-population differentiation, is a potential driver of evolutionary novelty. Our results provide a foundation for developing better conservation strategies for this widespread intertidal species.

The pronghorn spiny lobster Panulirus penicillatus is a highly valuable species which is widely distributed in Indo-West Pacific and Eastern Pacific regions. Mitochondrial DNA control region sequences (566–571 bp) were determined to investigate the population genetic structure of this species in the Indian Ocean. In total, 236 adult individuals of Panulirus penicillatus were collected from five locations in the Indian Ocean region. Almost all individuals had a unique haplotype. Intrapopulation haplotype (h) and nucleotide (π) diversities were high for each locality, ranging from h = 0.9986–1.0000 and π = 0.031593–0.043441. We observed distinct genetic isolation of population located at the northwestern and southwestern edge of the species range. Gene flow was found within localities in the central and eastern region of the Indian Ocean, probably resulting from an extended planktonic larval stage and prevailing ocean currents.