A time-series data analysis to examine effects of subsidies to fishery productions in Japan

A cointegration analysis is conducted to examine the effect of fishery subsidies on fisheries production using data compiled over more than 30 years in Japan. The results illustrate that one fishery production indicator (production value per fishermen) shows a positive relationship with one particular group of government financial transfer (GFT) (that is, government general service expenditures including cost for fishery managements, scientific researches, and other administrative activities). No other tested results between GFTs and fishery indicators showed a real relationship. Although further scrutiny is awaited, this study could provide an empirical basis for an argument that, under an effective fishing management system, fisheries subsidies do not necessarily cause production increases or negative impact on fishing stocks.     

Factors determining the distribution of a keystone understory taxon, dwarf bamboo of the section Crassinodi, on a national scale: application to impact assessment of climate change in Japan

The objective of this study was to identify climatic factors determining the distribution of a keystone understory taxon, section Crassinodi of the genus Sasa, and assess the impacts of climate change on the taxon. Relationships between the distribution of sect. Crassinodi and five climatic variables were explored using classification tree analysis. Potential habitats under current climate and future climate in 2081–2100 were predicted. Potential habitats were further divided into suitable and marginal habitats. The predictive accuracy of the model was assessed using receiver operating characteristic analysis and by comparing model predictions with an independent dataset. The model was reasonably accurate. It showed that the warmth index (WI) and snow cover were the most important climatic variables for Crassinodi distribution. Potential habitats were limited to cooler regions with WI <102.7°C month. Suitable habitats were limited to even cooler regions with WI <84.8°C month. The model also showed that areas with deeper snow than previously reported would provide suitable habitats for Crassinodi under some climatic conditions. In 2081–2100, 37.4% of current potential habitats are predicted to become non-habitats because of increases in WI. Most currently suitable habitats are predicted to vanish from western Japan by 2081–2100. Meanwhile, Hokkaido and high-elevation areas of eastern Honshu will sustain suitable habitats. Sect. Crassinodi, which is adapted to less snowy climates, is predicted to be more affected by climate change than sect. Sasa and Macrochlamys, which are adapted to snowy climates.     

Attachment and infection to MA104 cells of avian rotaviruses require the presence of sialic acid on the cell surface

To determine the characters of receptors on target cells for avian rotaviruses, the receptors on MA104 cells for the pigeon rotavirus PO-13, the turkey rotaviruses Ty-1 and Ty-3, and the chicken rotavirus Ch-1 were analyzed. Pretreatment of MA104 cells with neuraminidase greatly reduced the infection by all of the four avian rotavirus strains. Binding of the cell-attachment protein, purified VP8 expressed in bacteria, of strain PO-13 to MA104 cells was also inhibited by pretreatment of cells with neuraminidase. These findings suggest that avian rotaviruses primarily utilize sialic acid-containing molecules as receptors on MA 104 cells.     

Nested PCR检测狂犬病病毒方法的建立及病毒在小鼠体内的移行动态

应用建立的Nested PCR特异地检出狂犬病病毒株CVC、HEP-Flury、ERA、RC-HL、1008、Komatsug-awa的RNA,但对类狂犬病病毒Lagos bat、Duvenhage、Mokola及水泡性口膜炎病毒、轮状病毒、犬瘟热病毒均为阴性。该法敏感性很高,能检出3 TCID50或0.8pg的狂犬病病毒RNA。用该法测定了小鼠脑内感染CVS株后的病毒增殖和移行动态,对感染小鼠的主要内脏器官进行了病毒RNA检测,结果发现小鼠脑内感染CVS 5 d以后在其心、肝、脾、肺等内脏器官均检出了病毒RNA。     

What controls the distribution of the Japanese endemic hemlock, Tsuga diversifolia? Footprint of climate in the glacial period on current habitat occupancy

Plant distributions are thought to be controlled by climate at large scales, and by non-climatic factors including soil conditions, topography and biotic interactions at smaller scales. However, not all plant distributions are explained by the current environment. Lags between current plant distributions and suitable environment for them are suggested to exist, which is often called empty habitat. To identify the existence and cause of lags between current climate and the distribution of Tsuga diversifolia, climatic conditions for the species distribution were clarified and potential habitats under current and the last glacial maximum (LGM; 21 ka) climates have been projected. The relationships between T. diversifolia distribution and climatic variables were explored using a classification tree model and a generalized additive model based on high-resolution (ca. 1 km) climatic data and a nationwide distribution database. The models were highly accurate. We revealed that T. diversifolia requires high summer precipitation even in humid Japanese environments. Areas with cool and wet summers were classified as potential habitat. Empty habitat for the focal species was identified in Hokkaido. Meanwhile, no potential habitat was projected in Hokkaido under the LGM. Additional experiments that varied temperature and summer precipitation during the LGM showed that the potential habitat was projected in Hokkaido irrespective of temperature decrease if summer precipitation increased nearly equal to the current climate. These results suggest that T. diversifolia vanished from Hokkaido, where fossil evidence indicated its occurrence until the late Neogene, during the glacial periods of the Pleistocene because of increased summer dryness.     

The Near Eastern origin of cat domestication

The world's domestic cats carry patterns of sequence variation in their genome that reflect a history of domestication and breed development. A genetic assessment of 979 domestic cats and their wild progenitors-Felis silvestris silvestris (European wildcat), F. s. lybica (Near Eastern wildcat), F. s. ornata (central Asian wildcat), F. s. cafra (southern African wildcat), and F. s. bieti (Chinese desert cat)-indicated that each wild group represents a distinctive subspecies of Felis silvestris. Further analysis revealed that cats were domesticated in the Near East, probably coincident with agricultural village development in the Fertile Crescent. Domestic cats derive from at least five founders from across this region, whose descendants were transported across the world by human assistance.     

Dehydrotomatine and alpha-tomatine content in tomato fruits and vegetative plant tissues

Tomato plants (Lycopersicon esculentum) synthesize the glycoalkaloids dehydrotomatine and alpha-tomatine, possibly as a defense against bacteria, fungi, viruses, and insects. We used a high-performance liquid chromatography method with UV detection at 208 nm for the analysis of these compounds in various tissues. An Inertsil ODS-2 column with a mobile phase of acetonitrile/20 mM KH2PO4 (24/76, v/v) afforded good separation of the two glycoalkaloids in mini-tomato extracts, fruit harvested at different stages of maturity, and calyxes, flowers, leaves, roots, and stems. The two peaks appeared at approximately 17 and approximately 21 min. Recoveries from tomato fruit extracts spiked with dehydrotomatine and alpha-tomatine were 87.7 +/- 6.8 and 89.8 +/- 3.4% (n = 5), respectively. The detection limit is estimated to be 0.39 microg for dehydrotomatine and 0.94 microg for alpha-tomatine. The dehydrotomatine and alpha-tomatine content of tomatoes varied from 42 to 1498 and 521 to 16 285 microg/g of fresh weight, respectively. The ratio of alpha-tomatine to dehydrotomatine ranged from 10.9 to 12.5 in tomatoes and from 2.3 to 7.8 in the other plant tissues. These results suggest that the biosynthesis of the glycoalkaloids is under separate genetic control in each plant part. Degradation of both glycoalkaloids occurred at approximately the same rate during maturation of the tomatoes on the vine. An Inertsil NH2 column, with acetonitrile/1 mM KH2PO4 (96/4, v/v) as the eluent, enabled the fractionation of commercial tomatidine into tomatidenol and tomatidine, the aglycons of dehydrotomatine and alpha-tomatine, respectively. The information should be useful for evaluating tomatoes and vegetative tissues for dehydrotomatine/alpha-tomatine content during fruit development and their respective roles in host-plant resistance and the diet.