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Abstract
How are we to understand China’s decades-long sovereignty claim over Taiwan? One assumption upheld by many international relations scholars is that state behaviour will change according to a variance of polarity in the international system. Yet while China can flexibly manage its territorial issues elsewhere, its goal of unification with Taiwan has not changed despite multiple structural changes in the international system over the decades. This paper argues that historical and nationalist approaches alone do not explain China’s unswaying obsession with this island. Geopolitics plays a far more prominent role in the minds of Chinese leaders than scholars have previously acknowledged. Since 1949, China has viewed Taiwan as a geopolitical buffer protecting the security of Chinese coastal areas. China’s buffer thinking towards Taiwan was a significant factor in China’s decisions to launch military action against Taiwan in 1954, 1958, and 1996.
Larval amphibians are especially likely to encounter variation in temperature and resource availability because they live in a variety of aquatic habitats. In this study, plasticity in growth rates, survivorship, age and size at metamorphosis were examined in the Chinese brown frog (Rana chensinensis) under different combinations of rearing temperature and food level. Tadpoles reared at 23.2°C had larger mass at metamorphosis and a longer larval period than tadpoles reared at 25.3 and 28.1°C. High food level shortened the larval period and produced a larger size at metamorphosis. The interaction of rearing temperature and food level significantly influenced the growth and survival of Chinese brown frog tadpoles. At a low food level, tadpoles reared at 23.2°C displayed faster growth than tadpoles reared at the higher temperatures, and tadpoles had lower survival at 28.1°C than at the lower temperatures. Therefore, global warming or local manipulations of the environment could limit growth and development of Chinese brown frog tadpoles, resulting in low survival, but food availability may mediate effects of temperature. We suggest that Chinese brown frog tadpoles prefer cool a temperature and high food level for longer larval periods to capitalize on the opportunity of entering the terrestrial habitat with a larger body size.
Abstract
This study mainly investigated whether β-glucan or sodium alginate enhance the non-specific immune response of the spiny lobster, Panulirus interruptus. In experiments, lobsters were fed a diet containing one or the other of these compounds, to determine their effect on non-specific immune parameters in the short term (14 days). The lobsters were then bled to examine variance in total haemocyte count (THC), phenoloxidase activity, superoxide anion (O2 −) production, superoxide dismutase (SOD) activity, phagocytic ratio (PR), and phagocytic index (PI). The effects of treatment with various doses of β-glucan and sodium alginate were determined. The results showed that treatment with 1-2 g of β-glucan or 2-4 g of sodium alginate significantly increased THC, O2 − production, SOD activity, and PR. In conclusion, the immunomodulators β-glucan and sodium alginate can increase the non-specific immune response in spiny lobsters.
Abstract
This study was to examine the immunomodulatory effects of oxytetracycline (OTC) on the white shrimp Litopenaeus vannamei (Boone, 1931). Immune parameters were not suppressed by OTC treatment in haemocytes in vitro. A total of 96 healthy shrimp were divided into four groups. Group 1 was the control group. Group 2 received 50 mg OTC/kg body weight/day. Group 3 received 1 g β-glucan/kg feed. Group 4 received 50 mg OTC/kg body weight/day and 1 g/kg β-glucan. OTC residues were more highly accumulated in the hepatopancreas than in muscle tissue during the rearing period, and the addition of β-glucan prolonged the retention time of OTC in the muscle tissue. Additionally, dietary administration of OTC in combination with β-glucan facilitated the excretion of OTC from the hepatopancreas. Shrimp that orally ingested OTC alone had an elevated total haemocyte count, phagocytosis, superoxide anion production and prophenoloxidase activity, and these immunostimulatory effects were further enhanced in shrimp receiving OTC in combination.