Recursive Method for Nekrasov partition function for classical Lie groups

Nekrasov partition function for the supersymmetric gauge theories with general Lie groups is not so far known in a closed form while there is a definition in terms of the integral. In this paper, as an intermediate step to derive it, we give a recursion formula among partition functions, which can be derived from the integral. We apply the method to a toy model which reflects the basic structure of partition functions for BCD type Lie groups and obtained a closed expression for the factor associated with the generalized Young diagram.Comment: 21 pages;v2 comments and references adde

Parasite infection induces size-dependent host dispersal: consequences for parasite persistence

Host dispersal is now recognized as a key predictor of the landscape-level persistence and expansion of parasites. However, current theories treat post-infection dispersal propensities as a fixed trait, and the plastic nature of host's responses to parasite infection has long been underappreciated. Here, we present a mark-recapture experiment in a single host-parasite system (larval parasites of the freshwater mussel Margaritifera laevis and its salmonid fish host Oncorhynchus masou masou) and provide, to our knowledge, the first empirical evidence that parasite infection induces size-dependent host dispersal in the field. In response to parasite infection, large fish become more dispersive, whereas small fish tend to stay at the home patch. The observed plasticity in dispersal is interpretable from the viewpoint of host fitness: expected benefits (release from further infection) may exceed dispersal-associated costs for individuals with high dispersal ability (i.e. large fish) but are marginal for individuals with limited dispersal ability (i.e. small fish). Indeed, our growth analysis revealed that only small fish hosts incurred dispersal costs (reduced growth). Strikingly, our simulation study revealed that this plastic dispersal response of infected hosts substantially enhanced parasite persistence and occupancy in a spatially structured system. These results suggest that dispersal plasticity in host species is critical for understanding how parasites emerge, spatially spread, and persist in nature. Our findings provide a novel starting point for building a reliable, predictive model for parasite/disease management

Ecological value of gravel pit ponds for floodplain wetland fish

Floodplain wetlands support high biodiversity, but they have been degraded and geographically fragmented due to human activities. Some types of human-created waterbodies have received growing attention as alternative habitats for conserving wetland biodiversity. Gravel pit ponds (GPPs) are human-created wetlands formed when a gravel pit is excavated at or below the water table and filled with groundwater. Differences in community structure among GPPs and floodplain wetlands with respect to habitat characteristics are scarcely known, resulting in insufficient evaluations of the ecological value of GPPs for floodplain wetland species. In this study, we evaluated the ecological value of GPPs for wetland fishes in floodplain landscapes. We surveyed fish abundance, community composition, and 10 environmental factors in GPPs and two types of floodplain ponds (remnant ponds and river backwaters) to clarify the biotic and abiotic differences among the pond types. Environmental factors were similar among the pond types, with only water temperature and the distance from the main channel to the pond significantly lower in river backwaters. The richness and abundance of native fish species did not differ among the pond types, but species composition did. Rhynchocypris percnura sachalinensis, Carassius sp., and Lethenteron sp. N (one of the two cryptic species of Lethenteron reissneri) were selected as indicator species in GPPs, remnant ponds, and river backwaters, respectively. These results indicate that GPPs provide valuable habitats for wetland fishes in floodplain landscapes and support regional gamma diversity. Since many species inhabited the GPPs in this study, including red list species, appropriate management of GPPs is important to conserve wetland fishes

標津川自然再生プロジェクト

北海道東部を流れる標津川下流域では、国内で初めてとなる川の再蛇行化実験が実施された。実験は、直線化によって河道周辺に残された旧河道(河跡湖)の一つと、直線河道の再連結によって行われた。再蛇行化の前後に、直線河道と旧河道を村象として河道形状や地形に関する調査、藻類、底生動物、魚類に関する調査と安定同位体比による食物網構造の解析を行い、実験の評価を試みた。 室内実験と再蛇行試験区での調査から、河道の分流部での流速分布や土砂の堆積を予測するモデルを組み立てた。再蛇行後の蛇行河道は、直線河道では見られない縦横断形状の変化が見られたが、水深、流速、底質といった物理環境要素は河道間で異ならなかった。 再蛇行後、直線流路、蛇行流路ともクロロフィルa量は小さかったが、直線流路の堰き上げ下流部では著しく大きかった。蛇行流路(旧河道)の底生動物や魚類は、再蛇行化によって止水性から流水性に入れ替わった。底生動物にとって蛇行湾曲部の内岸側に形成される寄洲は重要な生息場であり、魚類にとっては外岸側で河岸浸食によって水中に倒れ込んだ樹木が重要な生息場であった。再蛇行前、直線流路と蛇行流路(旧河道)に生息する生物相の同位体比特性には違いがあり、両者の食物網構造は異なった。 再蛇行化実験では個々の研究成果が得られ、現在は、個々の成果の補完や分野を横断する研究テーマの発掘を検討している

Genetic structure of Vaccinium vitis-idaea in lowland cool spot and alpine populations : microrefugia of alpine plants in the midlatitudes

Local cool spots (wind-holes) in lowland areas of midlatitudes may act as microrefugia for cold-adapted species outside of their typical alpine habitats. We examined the genetic structure of Vaccinium vitis-idaea, a common alpine species in Japan, in eight lowland wind-hole and five surrounding alpine populations. We collected leaf samples and genotyped seven microsatellite loci. Clonal patches (genets) were common in almost all populations. An analysis of annual shoot growth suggested that individuals in the wind-hole populations were long-lived (> 500 years old). Genetic diversity (allelic richness) and differentiation (F (ST)) of the wind-hole populations were lower and higher than those of the alpine populations, respectively. No significant isolation-by-distance trend in the genetic structure was detected for the wind-hole or alpine populations. All wind-hole populations had negative inbreeding coefficients (F (IS)), suggesting no tendency toward homozygosity due to inbreeding, regardless of the small populations geographically isolated from the large alpine populations. Therefore, wind-holes may harbor genetically isolated but stable populations due to clonal growth, limited gene flow, and abortion of selfed seeds by early acting inbreeding depression. Analysis of molecular variance demonstrated that genetic variations among and within populations contributed more to regional genetic diversity than those between wind-hole and alpine populations, suggesting that the wind-hole and alpine populations are important for maintaining the genetic diversity of midlatitude V. vitis-idaea populations. On the other hand, Bayesian clustering showed that some wind-hole populations geographically close to the alpine populations had mixed genetic compositions of the alpine and wind-hole populations

A Human Reaching Movement Model for Myoelectric Prosthesis Control

This paper proposes a reaching movement model for the generation of desired trajectories within a myoelectric prosthesis training system. First, an experiment was performed to observe reaching movements with a non-impaired subject and a myoelectric prosthesis user. Reaching movements made by the prosthesis user were then adopted to construct a model based on a logistic function. The proposed model can be used to generate three trajectory types with a bell-shaped speed profile with the adjustment of only a few parameters.This work was partially supported by a Grant-in-Aid for Young Scientists B Number 26730111

A virtual myoelectric prosthesis training system capable of providing instructions on hand operations

This article proposes a virtual hand and a virtual training system for controlling the MyoBock—the most commonly used myoelectric prosthetic hand worldwide. As the virtual hand is controlled using the method also adopted for the MyoBock hand, the proposed system provides upper-limb amputees with operation sensibilities similar to those experienced in MyoBock control. It can also display an additional virtual hand for the provision of instructions on hand operation, such as the recommended posture for object grasping and the trajectory desirable to reach a target. In virtual hand control experiments conducted with an amputee to evaluate the proposed virtual hand’s operability, the subject successfully performed stable opening and closing with high discrimination rates (89.3±6.65%), thanks to the virtual hand’s incorporation of the MyoBock’s operational characteristics. A training experiment using the proposed system was also conducted with eight healthy participants over a period of 5 days. The participants were asked to perform the box and block test using the MyoBock hand in a real environment on the first and final days. The results showed that the number of blocks transported in 1 min significantly increased and that the participants using the instruction virtual hand changed the orientation of the hand approaching blocks from vertical to lateral. The outcomes of the experiment indicate that the proposed system can be used to improve MyoBock hand control operation both quantitatively and qualitatively.This work was partially supported by a Grant-in-Aid for Young Scientists B Number 26730111 and a Grant-in-Aid for Scientific Research C Number 26462242

Camera trapping assessment of terrestrial mammals and birds in rehabilitated forest in INIKEA Project Area, Sabah, Malaysian Borneo

The Innoprise-IKEA (INIKEA) Forest Rehabilitation Project in Kalabakan Forest Reserve, Sabah, was established to rehabilitate degraded forest afected by conventional logging and forest fres that occurred during an El-Nino event (1982–1983). The present study aimed to investigate the responses of ground-dwelling mammals and birds to the diferent rehabilitation practices in INIKEA: gap-cluster planting, line planting and liberation, where enrichment planting applied in both gap-cluster and line planting. A total of 74 camera traps were deployed at random locations across reforested INIKEA plots, including plots in control areas comprising naturally regenerated forest. A total of 6534 independent photographs of medium-to-large vertebrates from 7266 camera-trap nights representing 33 species from 14 families and 7 orders were obtained. Among the detected vertebrate species, 2 are listed as Critically endangered, 5 as Endangered, 8 as Vulnerable and 6 as Near threatened on the International Union for Conservation of Nature (IUCN) Red List of Threatened Species. Mousedeer was the most frequently photocaptured species, followed by muntjac, bearded pig, sambar deer, pig-tailed macaque and crested freback. The present study demonstrates that the rehabilitation methods applied in INIKEA have aided forest recovery, providing habitat for the ground-dwelling mammals and birds in Sabah. General forest structure, species richness and species composition did not signifcantly difer between the areas subjected to rehabilitation treatment and the control area. The results suggest that the liberation method should be abandoned to ensure a variety of food resources for animal species. Provided major forest components remain after disturbance, disturbed forest areas should be left to undergo natural recover

Camera-trapping assessment of terrestrial mammals and birds in rehabilitated forest in INIKEA Project Area, Sabah, Malaysian Borneo

The Innoprise-IKEA (INIKEA) Forest Rehabilitation Project in Kalabakan Forest Reserve, Sabah, was established to rehabilitate degraded forest affected by conventional logging and forest fires that occurred during an El-Nino event (1982–1983). The present study aimed to investigate the responses of ground-dwelling mammals and birds to the different rehabilitation practices in INIKEA: gap-cluster planting, line planting and liberation, where enrichment planting applied in both gap-cluster and line planting. A total of 74 camera traps were deployed at random locations across reforested INIKEA plots, including plots in control areas comprising naturally regenerated forest. A total of 6534 independent photographs of medium-to-large vertebrates from 7266 camera-trap nights representing 33 species from 14 families and 7 orders were obtained. Among the detected vertebrate species, 2 are listed as Critically endangered, 5 as Endangered, 8 as Vulnerable and 6 as Near threatened on the International Union for Conservation of Nature (IUCN) Red List of Threatened Species. Mousedeer was the most frequently photocaptured species, followed by muntjac, bearded pig, sambar deer, pig-tailed macaque and crested fireback. The present study demonstrates that the rehabilitation methods applied in INIKEA have aided forest recovery, providing habitat for the ground-dwelling mammals and birds in Sabah. General forest structure, species richness and species composition did not significantly differ between the areas subjected to rehabilitation treatment and the control area. The results suggest that the liberation method should be abandoned to ensure a variety of food resources for animal species. Provided major forest components remain after disturbance, disturbed forest areas should be left to undergo natural recovery