Polymerase chain reaction-restriction fragment length polymorphism analysis for species identification of hairtail fish fillets from supermarkets in Japan

Hairtail fillets are marketed as both fresh and frozen forms in retail outlets within Japan. The present study was undertaken to develop a rapid and reliable method for identification of the hairtail species in commercial fillets. A total of 64 fillet samples, caught from various localities within Japan and purchased from various supermarkets, were analyzed. Polymerase chain reaction (PCR) amplification of a portion of the mitochondrial DNA encoding 16S ribosomal RNA gene and subsequent restriction digestion of the amplified products, using Vspl endonuclease, generated different restriction patterns indicating two different species of hairtails in the fillet samples. The results indicated that the commercial hairtail fillets, labeled and marketed as ‘Tachiuo’ in Japan, were comprised of two species of hairtails with Trichiurus japonicus (commonly called Tachiuo) accounting for 47% and Trichiurus sp. 2 (commonly called Tenjikutachi) accounting for 53% of the analyzed samples. This simple and inexpensive PCR-restriction fragment length polymorphism analysis can be routinely applied to determine species composition of hairtails in commercial fillets.     

The effect of brown kelp phenology on abalone locomotion and spatial distribution: acoustic telemetry and spatially explicit individual-based model approach

In field studies of a species’ population size, the movement and distribution of the target organism beyond the study area affect the population size estimate. Estimates are derived based on the number of animals caught, and catch efficiency changes with distribution and locomotion of the animals. This study, using acoustic telemetry and unmanned aerial vehicle (UAV) mapping, revealed that the Ezo abalone, Haliotis discus hannai, alters its distance moved depending on its distance from brown kelp. In addition, we reproduced abalone locomotion and brown kelp phenology as individual-based models. In the model, abalone moved to deeper water during the spring/summer brown kelp growing season, while during autumn/winter, the model showed them moving to shallower water and aggregating around the remaining brown kelp. The timing of moving to shallower area in the model coincided with the fishing season. Fishers mainly catch abalone in shallower areas. Therefore, it is possible that fishing efficiency will not decline later in the fishing season because fishers can catch the abalone immigrating to the main fishing grounds and those aggregating around the brown kelp. Our model indicated the need for improvement in the DeLury method and the catch per unit effort (CPUE) trends used in the abalone fishing industry.

     

Quantitative chromosome map of a representative indica rice

The somatic chromosomes of standard indica diploid rice, IR 36, were squashed on glass slides and stained with Giemsa. The condensation patterns (CP) of prometaphase chromosomes were quantitatively analysed using CHIAS III software. The relative length and centromeric index (CI) were converted from CHIAS III to numerical data and calculated by EXCEL program. The ideogram based on CP of indica rice was established. There were 2 pairs of satellite chromosomes and the result was confirmed by fluorescence in situ hybridization using 45S rDNA as a probe. This revised version was published online in July 2006 with corrections to the Cover Date.     

Detection of Human Herpesviruses (HHVs) in Semen of Human Male Infertile Patients

Recently we demonstrated an ectopic expression of the human herpesvirus 1 thymidine kinase (HHV1-TK) gene by functioning of an intrinsic endogenous promoter in the transgenic rat (TG-rat), suggesting that HHV1 infection in humans induces expression of the TK gene with the ectopic promoter in the testis and results in accumulation of HHV1-TK protein, triggering male infertility similar to that in the TG-rat. Hence, in this study, we started to investigate a relationship between infection of herpesvirus and human male infertility. Semen was donated by Chinese male infertile patients (153 men, aged 21–49 years) with informed consent, followed by DNA preparation and analysis by PCR and DNA sequencing. Semen volume, sperm number and density, and sperm motility were examined. DNAs of HHV1, HHV4, HHV5 and HHV6 were confirmed by PCR, electrophoresis and DNA sequencing. Finally, virus DNA was identified in 59 patients (39%). The number of carriers was 39 (25%) for HHV1, 6 (4%) for HHV4, 33 (22%) for HHV5 and 3 (2%) for HHV6, respectively. Moreover, double-infection was found in 22 out of 59 specimens (37%), most of which were double-infection of HHV1 and HHV5 (15 out of 22 carriers). Though slight severity was present in some of the carriers, the relationship between virus infection and sperm impairment was not conclusive. Accordingly, it is essential to examine whether the viral HHV1-TK gene is expressed in the testis of the infertile human HHV carrier.     

Chromospheric anemone jets as evidence of ubiquitous reconnection

The heating of the solar chromosphere and corona is a long-standing puzzle in solar physics. Hinode observations show the ubiquitous presence of chromospheric anemone jets outside sunspots in active regions. They are typically 3 to 7 arc seconds = 2000 to 5000 kilometers long and 0.2 to 0.4 arc second = 150 to 300 kilometers wide, and their velocity is 10 to 20 kilometers per second. These small jets have an inverted Y-shape, similar to the shape of x-ray anemone jets in the corona. These features imply that magnetic reconnection similar to that in the corona is occurring at a much smaller spatial scale throughout the chromosphere and suggest that the heating of the solar chromosphere and corona may be related to small-scale ubiquitous reconnection.     

Continuous plasma outflows from the edge of a solar active region as a possible source of solar wind

The Sun continuously expels a huge amount of ionized material into interplanetary space as the solar wind. Despite its influence on the heliospheric environment, the origin of the solar wind has yet to be well identified. In this paper, we report Hinode X-ray Telescope observations of a solar active region. At the edge of the active region, located adjacent to a coronal hole, a pattern of continuous outflow of soft-x-ray-emitting plasmas was identified emanating along apparently open magnetic field lines and into the upper corona. Estimates of temperature and density for the outflowing plasmas suggest a mass loss rate that amounts to approximately 1/4 of the total mass loss rate of the solar wind. These outflows may be indicative of one of the solar wind sources at the Sun.     

环境激励条件建筑结构的试验建模研究

通过环境激励模态识别技术对一座中高层新结构大楼环境激励试验建模研究。首先介绍了试验模型设计 ,并在现场测量整栋大楼在环境激励下的振动响应。然后采用新发展的频率空间域方法 ( FSDD)进行模态识别 ,分别在 0～ 4.5 Hz和 0～ 6.5 Hz频率范围识别出 9阶弯曲和扭转模态频率和振型。采用频率空间域方法识别了结构的阻尼特性 ,并得到满意的结果。所得试验模型已成功应用于 CFT大楼的有限元动态模型修正。所研发的试验建模技术可望在结构响应预报 ,健康监测和振动控制中发挥重要作用     

Induction of 12-chromosome plants from anther culture in a tuberousSolanum

Summary Haploid plants (2n=12) were produced by anther culture from the tuber-bearing wild speciesS. verrucosum.