The first report of gynandromorphy in termites (Isoptera; Kalotermitidae; <Emphasis Type="Italic">Neotermes koshunensis</Emphasis>)

This is the first report of gynandromorphy in Isoptera. An Asian dry-wood termite, Neotermes koshunensis (Shiraki) [Kalotermitidae], possessing both male and female phenotypic characteristics, was found on Okinawa Island, Japan. This deformed individual showed morphological and anatomical hermaphroditism in the abdomen. The right side of the seventh sternite was the female form and contained an ovary, while the left side was the male form and contained a testis. Genotypic analysis revealed that this individual was a genotypic bilateral chimera. These results suggested that the termite was a bilateral gynandromorph with a male left side and a female right side. As reported previously in other insects, double fertilization (by two sperms, one with an X and one with a Y chromosome) of a binucleate egg is the most likely mechanism that generated this genotypic bilateral chimera. N. koshunensis has the ability to reproduce through parthenogenesis, in which the secondary polar body is likely to be used for nuclear phase recovery. If the second polar body in this mechanism has high fertility and healthy embryogenic potential, like an egg nucleus, some of gynandromorphs might be produced by a side effect of parthenogenetic ability.     

Unique Asymmetric Protrusion of Nerve Cord in the Amphioxus, Branchiostoma belcheri

The amphioxus is the only surviving prevertebrate segmented chordate. In this animal Hatschek's pit has long been regarded as a putative homologue of the adenohypophysis because of the presence of secretory granules and immunoreactive cells to vertebrate gonadotrophic hormone in this organ. We found that the nerve cord extends a protrusion to the pit along the right side of the notochord. Furthermore, secretory granules were found not only in the pit but also in the protrusion of the nerve cord. These results suggest that Hatschek's pit and the nerve protrusion are homologous to the adenohypophysis and neurohypophysis, respectively. We believe that this is an evidence for the presence of the neuroendocrine link between the central nervous system and Hatschek's pit in the amphioxus. Received: 2 November 1998 / Accepted in revised form: 11 February 1999     

Differences of two polychaete species reflected in enzyme activities

Polychaetes constitute most of the benthic macroinvertebrates in estuarine and coastal environments. We investigated the utilization of organic matter in two polychaete species, Capitella sp. I and Perinereis nuntia brevicirris, living in different coastal habitats. The protease activity of Capitella sp. I (89.7 μg mg⁻¹) was about 10 times that of P. nuntia brevicirris (8.0 μg mg⁻¹). High cellulase (endo-β-1,4-glucanase) activity was detected in P. nuntia brevicirris (3.2 μg mg⁻¹), whereas scarcely any was detected in Capitella sp. I. We isolated cDNA clones of protease mRNA from Capitella sp. I and of cellulase mRNA from P. nuntia brevicirris. The high protease activity of Capitella sp. I enabled it to survive in the sediment under a fish farm, where it degrades organic matter. In contrast, the high cellulase activity of the estuary-dwelling P. nuntia brevicirris allowed it to degrade organic matter originating from terrestrial areas.     

Protective action of zinc against lead poisoning in tilapia Oreochromis niloticus

The accumulation of lead (Pb) in tilapias Oreochromis niloticus, acclimatized in cement tanks, and fed once a day with pellets of commercial food with lead nitrate, was investigated by square wave anodic stripping voltammetry (SWV). The head (including head bones, proteins, and brain) was the main target of lead uptake by tilapias, with a small amount in muscle tissue. A high concentration of Pb was found in feces which indicated low absorption by the organism when fed with high Pb concentration. The protective effects of zinc (Zn) against the Pb poisoning, the accumulation of Pb in the heads of the fishes of 107.8?±?3.1?mg?kg^?1 and in the viscera of 57.1?±?2.9?mg?kg^?1 with consequent decrease of calcium (Ca) concentration, were observed. In spite of the experimental time of 16 months and higher Pb concentration in the dietary food of 320?mg?kg^?1, no death of tilapias was observed due to the protective action of Zn.     

Effects of daily nickel intake on the bio-accumulation,body weight and length in tilapia (Oreochromis niloticus)

Nickel pollution is a serious environmental problem, and its effects may provoke alterations in the ecosystem and in organism of animals and humans. Dermatitis, eczema, and asthma are some illnesses caused by Ni²⁺ poisoning. In this work, fish fed either Ni²⁺-enriched pellets or commercial pellets were studied. The amount of Ni²⁺ in fish were measurements by adsorptive stripping voltammetry (AdSV) with dimethylglyoxime as a complexing agent. The analysis of Ni²⁺ in fish by AdSV established that its accumulation occurs principally in viscera (670.86 ± 5.82 µg g^?1), in the head (697.12 ± 2.77 µg g^?1) and in the muscle (405.82 ± 3.26 µg g^?1), both after 12 months of experiments. Ni²⁺ adsorbs preferentially in organs such as the stomach, the intestine, and the kidneys and acts in the central nervous system as well. Tilapia growth and mass were significantly affected by Ni²⁺ poisoning. From statistical analysis, observed that the results for lengths, weights and metal concentration were different for each sampling at significance level of p < 0.05. The Ni²⁺ concentration in tilapia was enough to cause the death of tilapias; however, it did not occur because the presence of Zn²⁺ might act as protective agent of heavy metals.     

垃圾焚烧飞灰制备高温脱硫剂及其性能评价

利用不同地方的垃圾焚烧飞灰来制备高温炉内的脱硫剂,并利用热天平来研究飞灰脱硫剂(FA-脱硫剂)的固硫性能.实验结果表明,FA-脱硫剂的孔隙分布在2000nm左右,并且比生石灰具有更好的固硫能力.添加石膏后的FA-脱硫剂,其机械强度大大提高,但孔径结构变小,脱硫率也有所下降.添加10%(质量分数)水玻璃的FA-脱硫剂的机械强度相当于生石灰,脱硫效果更明显,比没有添加水玻璃时效果更好,孔径结构基本不变.这是由于水玻璃中的钠跟二氧化硫反应生成钠硫酸盐.     

Prevention of Deep Vein Thrombosis in VDU Work

This paper introduces preventive measures against Deep Vein Thrombosis (DVT) during Visual Display Units (VDU) work. Four experiments were conducted in order to address this issue. The effectiveness of the preventative measures was evaluated by measuring foot swelling. The results indicated that the following 3 methods would be particularly effective: (a) occasionally adopting a reclining posture with a footrest, (b) 10-min walking every 50-60 min of VDU work, and (3) stretching. In addition we predicted that taking a deep breath could sometimes be effective. DVT is likely to occur in daily life and its incidence can be related to the long-term postures associated with VDU work. This paper suggests that VDU workers should be aware of the risk of DVT and take preventative measures.     

Analysis of the environmental impact on a stream: is only tannery to blame?

The contribution of wastewater from a tannery industry to the pollution of a stream was investigated. The main parameters studied were biochemical oxygen demand, chemical oxygen demand, chromium, dissolved oxygen, fecal and total coliforms, nitrogen, oils and greases, pH, phosphorous, sulfides, suspended solids, turbidity, and volatile solids. Three sampling points were located: (1) at the discharge point of tannery wastewater, (2) 50 m upstream, and (3) 80 m downstream of discharge point. Also was investigated the pollution at the stream source.