bluuebunny/crossref_metadata_2025 huggingface dataset:
Toucans and thrushes as potential dispersers of seed-predatory weevil larvae in southeastern Brazil
Authors: Guix Juan Carlos , Ruiz Xavier
Published: January 2008

Only recently have the interrelationships between seed-predatory insects and frugivores (seed dispersers) been considered of interest for evolutionary studies. Within the framework of "evolutionary triads," insect dispersion by frugivores that eat insect-infested fruits has been predicted. Such dispersal requires that insects survive passage through frugivore stomachs. In this paper we document this in the case of a weevil (Revena rubiginosa) infesting the nut of a palm tree (Syagrus romanzoffiana) and an unidentified weevil infesting the seed of a tree belonging to the genus Eugenia (Myrtaceae). The fruits of both trees are eaten by toucans (Ramphastos dicolorus and R. vitellinus) and those of the palm also by thrushes (Turdus rufiventris).
Organization of the cytoskeleton in brine shrimp setal cells is molt-dependent
Authors: MacRae Thomas H. , Freeman John A.
Published: January 2008

Fluorescence microscopy was used to examine the cytoskeleton in setal cells and antennae of the brine shrimp Artemia franciscana. Each setal cell has an elongated apical process that contains bundles of microtubules and microfilaments. When the organism molts, the apical process telescopes reversibly through the setal cell body into the hemocoel of the antenna. Staining of larval-stage Artemia with four monoclonal anti-tubulin antibodies (DM1 A, TAT, YL1/2, KMX) and with rhodamine–phalloidin indicated that the cytoskeletal elements were stable, remaining assembled as co-localized bundles in telescoping setal cells. Microtubule stability was suggested by previous observations of detyrosinated tubulin in setal cell extensions, but the microtubules were not completely detyrosinated, as shown by their interaction with YL1/2. Foci of tubulin staining within the antenna, enrichment of the microfilaments associated with the invaginating setal cell membrane, and the spatial distribution of other cytoskeletal elements were indicative of dynamic processes used in shape change during molting. Fluorescent labelling also revealed microtubules and microfilaments in tendinal cells, specialized epidermal cells that attach muscle in the antenna to the overlying cuticle.
"Home or away?" The effect of mode of locomotion on consumption of sugar by bumble bees (Hymenoptera: Apidae)
Authors: Plowright C. M. S. , Reid S. L. , Plowright R. C.
Published: January 2008

The results of two experiments confirmed predictions from the hypothesis that bumble bees use mode of locomotion rather than distance from the hive in discriminating between food in the hive and in the field ("home" and "away"). When the distance between the hive and a feeder containing sugar solution was manipulated, for bees walking from the hive, the time spent ingesting the sugar solution did not vary with distance. When the mode of locomotion was manipulated, bees spent almost 4 times as much time extracting sugar solution from the feeder when they were required to fly to the food as when they were required to walk.
Do maternal burrower bugs, Sehirus cinctus Palisot (Heteroptera: Cydnidae), use spatial and chemical cues for egg discrimination?
Authors: Kight Scott L.
Published: January 2008

Female Sehirus cinctus Palisot (Heteroptera: Cydnidae) dig shallow burrows in which they guard their eggs and provision young nymphs. Because maternal females often oviposit in close proximity to other females, they must discriminate between their own and strange burrows to avoid investing in unrelated young. Observations that foraging females adhere to precise "trails" indicate that maternal females may use pheromonal cues to locate their burrows. Egg-discrimination trials indicate that maternal females unfamiliar with a test arena do not distinguish between their own eggs and similar strange eggs. However, when maternal females were allowed 24 h experience with the test arena, they chose to guard eggs located where they had previously brooded, even if the eggs were not their own. In addition, maternal females preferred recently brooded eggs over eggs that had been isolated for 24 h. These results indicate that foraging females use spatial and chemical cues to discriminate their own eggs from strange eggs.
Aquatic insect populations in transplanted and natural populations of the purple pitcher plant, Sarracenia purpurea, on Prince Edward Island, Canada
Authors: Hardwick M. Loretta , Giberson Donna J.
Published: January 2008

In early July 1991, 234 pitcher plants (Sarracenia purpurea) were transplanted from a Prince Edward Island bog being mined for peat into three bogs that varied with respect to previous pitcher plant abundance. One bog had a thriving natural pitcher plant population prior to transplant, while the other two had fewer than three pitcher plants. Between mid-June and late August 1993, abundances of the pitcher plant inquilines Wyeomyia smithii (Diptera: Culicidae), Metriocnemus knabi (Diptera: Chironomidae) and an unidentified sarcophagid fly (Diptera: Sarcophagidae) from transplant bogs were compared with remaining populations in the source bog and with other natural populations. Of the three inquilines, W. smithii was the most severely affected by transplant; it was extremely rare or absent in transplanted pitchers, although it was found in all other bogs investigated on Prince Edward Island. Metriocnemus knabi larvae were common in all bogs investigated, except for those transplant bogs where pitcher plants were rare prior to transplant. Sarcophagid larvae were found in all of the bogs sampled, and were apparently unaffected by transplant. Desiccation during the transplant process, as well as the time of the transplant, may play a role in the success of recolonization of the pitcher plants after transplanting.
Bat communities and deforestation in French Guiana
Authors: Brosset André , Charles-Dominique Pierre , Cockle Anya , Cosson Jean-François , Masson Didier
Published: January 2008

The impact of deforestation on the composition and dynamics of bat communities received close attention during a 15-year survey of the bats of French Guiana. Overall, deforestation lowers species richness: 48 of the 75 bat species from primary forest, mainly mature-forest phyllostomids, were not found in large areas that had been deforested for a long time. The 27 "rare" species, each represented by fewer than 6 of 8031 captures, had been apparently virtually eliminated from deforested areas. These altered habitats had been repopulated by a few opportunistic frugivorous phyllostomid species and by species belonging to the widespread insectivorous families Vespertilionidae and Molossidae. Habitats altered by humans harbor over four times as many individual bats as primary rain forest. This rise in both frugivorous and insectivorous bat populations in areas of degraded vegetation appears linked to the abundance of bat-dispersed pioneer' fruiting plant species available to phyllostomids and the multiplication of roosting sites for vespertilionids and molossids in human habitats. The species richness of local bat communities is positively influenced by the presence of forest corridors or the immediate proximity of a forest block.
Population cycles in the Varied Thrush (Ixoreus naevius)
Authors: Wells Jeffrey V. , Rosenberg Kenneth V. , Tessaglia Diane L. , Dhondt André A.
Published: January 2008

The Varied Thrush (Ixoreus naevius), an endemic species of the Pacific Northwest of North America, shows dramatic year-to-year changes in wintering abundance. These changes have not, however, been systematically examined using standardized data. Using Project FeederWatch data from 1988–1989 to 1994–1995 we found that Varied Thrushes showed a biennial cyclic change in abundance within most of their normal wintering range. This cyclic pattern was also evident in Christmas Bird Count and Breeding Bird Survey data from the same time period. There was no difference in the extent or location of the winter range or in the distribution of elevations of Varied Thrush records between years of high and low abundance. More feeders had single Varied Thrushes in years of high abundance than in years of low abundance. Longer term (1969–1970 to 1994–1995) Christmas Bird Count and Breeding Bird Survey data showed a more variable pattern, with abundance peaks every 2–3 years. The number of vagrant Varied Thrushes from eastern North America reported in Audubon Field Notes winter season reports was not correlated with abundance in the normal wintering and breeding areas but was correlated with the number of Varied Thrushes tallied on southern California Christmas Bird Counts. These results suggest that patterns of vagrancy in Varied Thrushes are largely independent of population changes within the normal wintering area.
Use of stable isotopes to determine diets of living and extinct bears
Authors: Hilderbrand G. V. , Farley S. D. , Robbins C. T. , Hanley T. A. , Titus K. , Servheen C.
Published: January 2008

The potential use of stable-isotope analyses (δ13C and δ15N) to estimate bear diets was assessed in 40-day feeding trials using American black bears (Ursus americanus). Bear plasma and red blood cells have half-lives of ~4 days and ~28 days, respectively. The isotopic signature of bear plasma is linearly related to that of the diet, and with the exception of adipose tissue, there is no isotopic fractionation across bear tissues. Isotopic analyses were used to estimate the diets of three bear populations: Pleistocene cave bears (U. speleaus) in Europe, grizzly bears (Ursus arctos horribilis) inhabiting the Columbia River drainage prior to 1931, and brown bears (U. arctos) of Chichagof and Admiralty islands, Alaska. Cave bears were omnivores with terrestrially produced meat contributing from 41 to 78% (58 ± 14%) of their metabolized carbon and nitrogen. Salmon contributed from 33 to 90% (58 ± 23%) of the metabolized carbon and nitrogen in grizzly bears from the Columbia River drainage. Finally, most brown bears on Chichagof and Admiralty islands feed upon salmon during the late summer and fall; however, a subpopulation of bears exists that does not utilize salmon.
Localization of mRNA for the proton pump (H+-ATPase) and exchanger in the rainbow trout gill
Authors: Sullivan Gary V. , Perry Steve F. , Fryer James N.
Published: January 2008

In situ hybridization was performed on sections of rainbow trout (Oncorhynchus mykiss) gill tissue using oligonucleotide probes complementary to the mRNA of the 31-kilodalton subunit of the bovine renal V-type H+-ATPase or rat kidney Band 3 anion exchanger ([Formula: see text] exchanger). This was conducted in conjunction with measurements of whole-body net acid fluxes and blood acid–base status during imposed conditions of respiratory acidosis (external hypercapnia) or metabolic alkalosis (NaHCO3infusion). A positive hybridization signal for the H+-ATPase mRNA was localized predominantly in lamellar epithelial cells and was less apparent in cells associated with the filament or interlamellar regions. The H+-ATPase hybridization signal was enhanced during hypercapnic acidosis concurrently with a marked increase in whole-body net acid excretion. A positive hybridization signal for the [Formula: see text] exchanger mRNA was observed in epithelial cells on both the filament and lamella. During metabolic alkalosis induced by intra-arterial infusion of NaHCO3, there was a marked increase in the [Formula: see text] exchanger mRNA hybridization signal in cells on both the filament and lamella that occurred concurrently with a decrease in net acid excretion. The results of this study support the existence of a V-type H+-ATPase and a [Formula: see text] exchanger in rainbow trout gill epithelial cells and demonstrate that alterations in gene expression for the pump–exchanger may be a significant mechanism underlying the altered rates of net acid equivalent excretion during acid – base disturbances.
Haemoparasitic protozoans (Plasmodiidae and Haemogregarinidae) from a New Caledonian gekkonid lizard, Rhacodactylus leachianus
Authors: Dollahon Norman R. , Bauer Aaron M. , Russell Anthony P.
Published: January 2008

A Plasmodium sp. and a haemogregarine were found in Giemsa-stained blood smears of a Rhacodactylus leachianus, an endemic New Caledonian gekkonid lizard. Both parasites were observed in mature erythrocytes only. The haemogregarines were found in a lateral position and the stages of Plasmodium sp. were polar or lateropolar in the cells. Mature schizonts of the latter were often fan-shaped, producing 4–10 merozoites. This is the first record of blood parasites in a New Caledonian vertebrate and the first record of a Plasmodium from a carphodactyline gecko. The Plasmodium sp. is unlike those described from Australian or New Zealand lizards, but is referable to the subgenus Lacertamoeba. The biogeographic affinities of these parasites remain unclear and may reflect either ancient Gondwanan affinities or more recent southeast Asian connections via more highly vagile lizard invaders of New Caledonia.
Diel and annual variation in plasma cortisol concentrations among wild and captive harbor seals (Phoca vitulina)
Authors: Gardiner Karen J. , Hall Ailsa J.
Published: January 2008

Annual and diel changes in plasma cortisol concentrations were investigated among wild and captive harbor seals (Phoca vitulina) of various sex and age classes. No significant effects of age, sex, or season were found in captive animals. However, significant inter-individual differences between two juvenile males were noted during both the breeding/molt (p = 0.041) and postbreeding/postmolt (p = 0.001) seasons. Seasonal and sex- and age-related differences were found among wild harbor seals. Across all sex and age categories, mean cortisol concentrations during the postbreeding and prebreeding seasons were significantly different from those measured during the breeding season (p = 0.014 and p = 0.038, respectively), but did not differ from each other. When each sex and age group was examined separately, seasonal effects were significant for mature females (p = 0.009) and mature males (p = 0.048). Differences in plasma cortisol concentration between captive and wild animals of the same sex during the same seasons were highly significant, particularly in mature animals (between p < 0.0001 and p = 0.035). There was a diel pattern of plasma cortisol concentrations in samples collected from captive animals over a 24-h period. Mean concentrations differed between samples collected during the hours of light and dark, being highest at night (p = 0.009), peaking around 01:00, and dropping again at around 13:00. Annual and diel patterns of plasma cortisol concentrations occur in harbor seals, and seasonal differences may relate to important physiological and behavioral phases in the harbor seals' annual cycle.
Developmental and seasonal changes in resting metabolic rates of captive female grey seals
Authors: Boily Patrice , Lavigne David M.
Published: January 2008

Resting metabolic rate (RMR) data obtained from five juvenile and three adult female grey seals (Halichoerus grypus) in captivity over a period of 3.5 years were examined for developmental and seasonal changes. Three juveniles exhibited a significant relationship between log10 RMR and log10 mass, with individual slopes ranging from 0.42 to 1.62. Two of these exhibited a significant relationship between log10 RMR and log10 age. The remaining two juveniles and the three adults exhibited no significant relationship between RMR and body mass. With increasing size and age, RMRs of juveniles approached predicted values for adult mammals, but the large variation made it difficult to establish the precise age at which they achieved an adult-like RMR. RMRs of adults and juveniles exhibited marked seasonal changes. In juveniles, seasonal changes in RMR were limited to the annual moult, when the average RMR was 35% higher than during the rest of the year. In adults, changes in RMR were not limited to the time of the annual moult; rather, RMR was lower (by up to 50%) in the summer than during other seasons.
Physiological effects on dive patterns and foraging strategies in yearling Weddell seals (Leptonychotes weddellii)
Authors: Burns Jennifer M. , Castellini Michael A. , Schreer Jason F.
Published: January 2008

Fifteen yearling Weddell seals (Leptonychotes weddellii) were captured, measured, weighed, bled, equipped with time–depth recorders, and released to determine if diving behavior was related to physical condition. Upon recovery of the time–depth recorders, dives were classified into four types based on shape, using cluster analysis. Based on maximum depth, two groups were further subdivided, for a total of seven types. The mean and maximal dive depth, duration, and frequency were determined for each yearling for all dive types combined and for each type separately. Stepwise regression and ANOVA techniques were used to test the relationship between diving behavior and physiological and morphometric measurements. In general, half of the variation in the pooled diving behavior could be explained by body-size differences. Larger yearlings made longer and shallower dives than smaller yearlings. Dive patterns suggested that large yearlings foraged primarily on small shallow-water prey items, while small yearlings concentrated on energy-dense deep-water prey. However, the interpretation of diving behavior, foraging locations, and diet that resulted from separating individuals and dive types was very different from that based on average diving behavior. This argues against ignoring variation among individuals and using only average diving behavior when describing marine mammal dive patterns.
Clearance of laboratory-cultured bacteria by freshwater bivalves: differences between lentic and lotic unionids
Authors: Silverman Harold , Cherry Julie S. , Lynn John W. , Dietz Thomas H. , Nichols S. J. , Achberger Eric
Published: January 2008

Nine species of unionids cleared laboratory-raised Escherichia coli from artificial pond water. The six unionid species collected from rivers had higher clearance rates than the three species collected from ponds, when clearance was normalized to millilitres per gram of dry tissue mass per minute. Analysis of variance indicated that all lotic unionids examined form a group with similar clearance rates. When normalized on the basis of gill surface area, rates of clearance by all of the lotic unionids become remarkably similar to one another regardless of mass, but differ significantly from those of the lentic unionids. The cirri found on the laterofrontal cells of the gills of lotic unionids tend to be complex, containing > 25 cilia per cirral plate, while the cirri of the unionid species collected from ponds have smaller cirri (< 16 cilia per cirral plate). There was a strong correlation between cirral surface area (mm2) per milligram of dry tissue and clearance rate among the unionid species studied. As a comparison, Corbicula fluminea and Dreissena polymorpha were also examined and both tended to clear bacteria more rapidly than the lotic unionids.
Patterns of mouflon (Ovis gmelini) survival under moderate environmental conditions: effects of sex, age, and epizootics
Authors: Cransac N. , Hewison A. J. M. , Maublanc M. L. , Gaillard J. M. , Cugnasse J. M.
Published: January 2008

We estimated survival probabilities over a 9-year period for an introduced population of Mediterranean mouflon (Ovis gmelini), applying capture – recapture models to resighting data from individually marked animals. Survival was high and constant among lambs, yearling males, and adults of both sexes, and we were unable to detect senescence among old animals. Survival of female yearlings varied widely among years. No difference in survival probabilities between the sexes was detected, indicating that the survival costs of sexual selection were low in this dimorphic species. We suggest that these results may be explained by a lack of limiting conditions on this study site. An outbreak of keratoconjunctivitis during the rut of 1993 caused a marked fall in annual survival for both sexes. Among males, this decline was constant for all ages (approximately 23%), but for females the impact of the disease varied in relation to age, with young ewes particularly affected. Otherwise, the population appears to be stable and we hypothesise that the removal of animals for export and through hunting, together with stochastic events such as periodic epizootics, maintains mouflon numbers at a level where the influence of density-dependent resource limitation on survival is limited.
Ecology of the arboreal tropidurid lizard Tropidurus (=Plica) umbra in the Amazon region
Authors: Vitt Laurie J. , Zani Peter A. , Avila-Pires Teresa Cristina S.
Published: January 2008

The tropidurid lizard Tropidurus umbra lives on medium-sized trees in lowland tropical forest of the Amazon region. Individuals may be active on tree trunks in sun or shade, with most activity occurring from 11:00 to 13:00. Body temperatures average 29.1 °C. The diet consists nearly exclusively of ants and there is no relationship between prey size and lizard size. Females reach sexual maturity at 79 mm snout–vent length (SVL) and males at 78 mm SVL. Although there appears to be no sexual dimorphism in SVL, males have relatively larger heads than females. Clutch size is usually two eggs and females appear to produce more than one clutch per season. Comparisons with other studied tropidurid lizards suggest that dietary specialization on ants, reduced sexual dimorphism, and reduced clutch size are derived characters.
Helminth communities in bullfrogs (Rana catesbeiana), green frogs (Rana clamitans), and leopard frogs (Rana pipiens) from New Brunswick, Canada
Authors: McAlpine Donald F.
Published: January 2008

Twenty-three helminth species were identified from bullfrogs, Rana catesbeiana, green frogs, R. clamitans, and leopard frogs, R. pipiens, in New Brunswick. Digeneans dominated adult helminth communities in the aquatic bullfrog and semi-aquatic green frog; nematodes were dominant in the more terrestrial leopard frog. In green frogs and leopard frogs, richness and abundance were greatest in adults; in bullfrogs, juveniles showed the greatest richness and abundance. An increase in vertebrates in the diet of adult bullfrogs influences helminth communities in bullfrogs. Where Glypthelmins quieta and nematodes, which infect the host by skin penetration, predominate in green frogs and leopard frogs, respectively, the increase in epidermal area with age probably influences helminth abundance. Adult female leopard frogs are larger than males and harbour greater numbers of helminths. Within the most heavily sampled component communities only larval digeneans, and less frequently nematodes with direct life cycles, were common (i.e., in > 50% of hosts); other taxa were generally present at prevalences of < 20% and intensities of < 10 helminths per frog. Although wetland characteristics and helminth transmission dynamics play a role in producing variation in helminth communities among sites, ontogenetic shifts in diet and sexual size dimorphism within these anuran species are important in shaping helminth communities in individual frog hosts.
ELEMENTAL ANALYSIS OF ATMOSPHERIC PARTICLES COLLECTED ON POLYTETRAFLUOROETYLENE (PTFE) FILTER USING IN-AIR HELIUM ION INDUCED X-RAY EMISSION METHOD
Authors: SAITOH KATSUMI , HAMANO TSUYOSHI , ISO HIROYUKI , ISHIKAWA TAKAHIRO , IMASEKI HITOSHI
Published: January 2008

In order to confirm the availability of an in-air Helium ion induced X-ray emission method for multi-elemental analysis of polytetrafluoroetylene (PTFE) filter sample containing atmospheric particles, NIST urban particulate matter (SRM 1648) collected on PTFE filter using a special small chamber was analyzed by an in-air PIXE method with Helium ions and a proton beam. In addition, we analyzed 10 elements, mixing a standard solution with different concentrations to confirm detection sensitivity of characteristic X-ray peaks. As a result, it is suggested that 1) elements that are lighter than Zn and Pb can be satisfactorily measured using the in-air Helium ion induced X-ray emission method if the amount contained in the filter sample is at least 0.1 mg/L, i.e., 15 ng/cm2, 2) the in-air Helium ion induced X-ray emission method is useful as a method for quantitatively analyzing the light elements such as Mg , Al , Si , S and Cl that are important for identifying the behavior and characteristics of atmospheric particles from the PTFE filter sample containing atmospheric particles, and 3) in the case of the PTFE filter sample containing atmospheric particles, it is possible to measure elements from Mg to Pb by means of analysis using Helium ions and protons.
PION AND MUON MASS DIFFERENCE: A DETERMINING FACTOR IN ELEMENTARY PARTICLE MASS DISTRIBUTION
Authors: SHAH G. N. , MIR T. A.
Published: January 2008

The most fundamental to the elementary particles is the mass they possess and it would be of importance to explore a possible relationship amongst their masses. Here, an attempt is made to investigate this important aspect irrespective of their nature or scheme of classification. We show that there exists a striking tendency for successive mass differences between elementary particles to be close integral/half integral multiple of the mass difference between a neutral pion and a muon. Thus indicating discreteness in the nature of the mass occurring at the elementary particle level. Furthermore, this mass difference of 29.318 MeV is found to be common to the mass spectra of leptons and baryons, implying thereby existence of a basic mechanism linking elementary particles responding to different interactions.
FLUCTUATIONS IN URBAN TRAFFIC NETWORKS
Authors: CHEN YU-DONG , LI LI , ZHANG YI , HU JIAN-MING , JIN XUE-XIANG
Published: January 2008

Urban traffic network is a typical complex system, in which movements of tremendous microscopic traffic participants (pedestrians, bicyclists and vehicles) form complicated spatial and temporal dynamics. We collected flow volumes data on the time-dependent activity of a typical urban traffic network, finding that the coupling between the average flux and the fluctuation on individual links obeys a certain scaling law, with a wide variety of scaling exponents between 1/2 and 1. These scaling phenomena can explain the interaction between the nodes' internal dynamics (i.e. queuing at intersections, car-following in driving) and changes in the external (network-wide) traffic demand (i.e. the every day increase of traffic amount during peak hours and shocking caused by traffic accidents), allowing us to further understand the mechanisms governing the transportation system's collective behavior. Multiscaling and hotspot features are observed in the traffic flow data as well. But the reason why the separated internal dynamics are comparable to the external dynamics in magnitude is still unclear and needs further investigations.
STOCHASTIC RESONANCE OF NON-MARKOVIAN RENEWAL PROCESSES
Authors: HU MINGHUI , SHAO HUIHE
Published: January 2008

The work discusses a response to the alternating external field of a stochastic resonance (SR) within the framework of the three-state system non-Markovian renewal processes. In the present paper, we provide an alternative description of the situation within the framework of a generalized master Markovian equation.
FUNDAMENTALS OF MEDIA THEORY
Authors: OVCHINNIKOV SERGEI
Published: January 2008

Media theory is a new branch of discrete applied mathematics originally developed in mid-nineties to deal with stochastic evolution of preference relations in political science and mathematical psychology. The theory focuses on a particular semigroup of ‘messages’ acting as transformations of a set of ‘states’, called a ‘medium’, whose axioms are both strong and natural. The term ‘medium’ stems from a particular application in which the transformations formalize the effects, on an individual, of ‘tokens’ of information delivered by the environment—that is, the ‘medium’. However, many different types of examples can be found, ranging from learning spaces to hypercube computers, suggesting that this concept is ubiquitous. The paper presents very basic concepts and results of media theory and is aimed at a wide body of researchers in discrete applied mathematics.
ROBUST WAVELET-DOMAIN WATERMARK SCHEME BASED ON FUZZY TECHNOLOGY
Authors: JIN CONG
Published: January 2008

Digital watermark technology has been proposed as an effective method to protect the copyright of multimedia data. An adaptive image watermark scheme based on fuzzy inference system that in discrete wavelet transform domain is proposed. By exploiting the brightness and texture characteristics of human visual system and considering properties of the original image wavelet coefficient, a fuzzy inference system is designed whose inputs are parameters of brightness and texture of the original image and output is the strength of embedded watermarks. It ensures that the watermark embedding strength is determined adaptively. The experimental results show that the watermarks embed by the proposed scheme are robust against attacks commonly used image processing methods such as JPEG compression, Gaussian noise, cropping, mean filtering, median filtering, rotation, and rescaling etc. Proposed scheme are shown to provide very good results in term of image imperceptibility, too.
FORECASTING LCD TV DEMAND USING THE FUZZY GREY MODEL GM(1,1)
Authors: TSAUR RUEY-CHYN , LIAO YI-CHUN
Published: January 2008

LCD TV is a rather newly developed product, with limited data available for sales of all panel sizes, and these are collected in a rather vague manner by some research institutes. Therefore, we propose using the fuzzy grey model GM(1,1) with fuzzy-input value to extrapolate the LCD TV demand with fuzzy-output value. By using the fuzzy grey model GM(1,1) we succeeded in forecasting LCD TV demands with limited fuzzy-input data, and carried out a sensitivity analysis to show its robustness for modeling.
PERFORMANCE EVALUATION OF A LARGE SCALE DISTRIBUTED DISASTER INFORMATION NETWORK SYSTEM
Authors: ECHIGO HIROAKI , SHIBATA YOSHITAKA , TAKAHATA KAZUO
Published: January 2008

In this paper, a robust and large scale resident-oriented safety information system on the occurrence of the various disasters constructed over a nationwide high-speed network is introduced. The evacuated residents can register their safety information to the local safety information servers in the evacuation area whether they can safely evaluated or not using mobile PCs or terminals at the evacuation place or mobile terminals on the way of evacuation. All of the local information servers are connected each other by wireless network and the safety information can be sent an upper-layer database in the district area and finally integrated into a district safety information in that region. In our system some of the damaged local servers due to the disaster can be detected and recovered by the upper-layer database server. On the other hand, the upper-layer database servers are backed up by mirror servers located at mutually different locations with long distance to isolate the influence of the same disaster when the some of them were destroyed or disordered. Thus, by introducing two levels of redundancy and backup functions, more large scale and robust safety information database system can be realized. A prototype system is constructed over Japan Gigabit Network (JGN2) to evaluate the performance of the suggested system. Through the performance evaluation for the prototype system, we could verify the usability and scalability of our suggested system.
THE PARALLEL CRANK-ROCKER FLAPPING MECHANISM: AN INSECT-INSPIRED DESIGN FOR MICRO AIR VEHICLES
Authors: CONN ANDREW T. , BURGESS STUART C. , CHUNG SENG LING
Published: January 2008

This paper presents a novel micro air vehicle (MAV) design that seeks to reproduce the unsteady aerodynamics of insects in their natural flight. The challenge of developing an MAV capable of hovering and maneuvering through indoor environments has led to bio-inspired flapping propulsion being considered instead of conventional fixed or rotary winged flight. Insects greatly outperform these conventional flight platforms by exploiting several unsteady aerodynamic phenomena. Therefore, reproducing insect aerodynamics by mimicking their complex wing kinematics with a miniature flying robot has significant benefits in terms of flight performance. However, insect wing kinematics are extremely complex and replicating them requires optimal design of the actuation and flapping mechanism system. A novel flapping mechanism based on parallel crank-rockers has been designed that accurately reproduces the wing kinematics employed by insects and also offers control for flight maneuvers. The mechanism has been developed into an experimental prototype with MAV scale wings (75 mm long). High-speed camera footage of the non-airborne prototype showed that its wing kinematics closely matched desired values, but that the wing beat frequency of 5.6 Hz was below the predicted value of 15 Hz. Aerodynamic testing of the prototype in hovering conditions was completed using a load cell and the mean lift force at the maximum power output was measured to be 23.8 mN.
A novel PPARα agonist ameliorates insulin resistance in dogs fed a high-fat diet
Authors: Tsunoda Masaki , Kobayashi Naoki , Ide Tomohiro , Utsumi Mari , Nagasawa Michiaki , Murakami Koji
Published: January 2008

Agonism of peroxisome proliferator-activated receptor (PPAR) α, a key regulator of lipid metabolism, leads to amelioration of lipid abnormalities in dyslipidemic patients. However, whether PPARα agonism is an effective form of therapy for obesity-related insulin resistance associated with lipid abnormalities is unclear. The present study investigated the effects of a potent and subtype-selective PPARα agonist, KRP-101, in a nonrodent insulin-resistant animal model under pair-fed conditions. Beagle dogs were fed a high-fat diet for 24 wk to induce insulin resistance. During the final 12 wk, 0.03 mg·kg−1·day−1KRP-101 ( n = 5) or vehicle ( n = 5) was administered orally once a day. KRP-101 administration resulted in a significantly lower weight of overall visceral fat, which is associated with increased adiponectin and decreased leptin in serum. KRP-101 administration improved hyperglycemia and hyperinsulinemia as well as dyslipidemia in dogs fed a high-fat diet. Oral glucose tolerance test showed that KRP-101 administration improved glucose intolerance. The KRP-101 group showed a markedly lower hepatic triglyceride concentration. Lipid oxidation was increased in the liver and skeletal muscles of the KRP-101 group. These findings in the dog model suggest that the use of potent and subtype-selective PPARα agonists as a potentially relevant therapeutic approach to treat human insulin resistance associated with visceral obesity.
Hyperinsulinemic rats are normotensive but sensitized to angiotensin II
Authors: Johansson Maria E. , Andersson Irene J. , Alexanderson Camilla , Skøtt Ole , Holmäng Agneta , Bergström Göran
Published: January 2008

The effect of insulin on blood pressure (BP) is debated, and an involvement of an activated renin-angiotensin aldosterone system (RAAS) has been suggested. We studied the effect of chronic insulin infusion on telemetry BP and assessed sympathetic activity and dependence of the RAAS. Female Sprague-Dawley rats received insulin (2 units/day, INS group, n = 12) or insulin combined with losartan (30 mg·kg−1·day−1, INS+LOS group, n = 10), the angiotensin II receptor antagonist, for 6 wk. Losartan-treated (LOS group, n = 10) and untreated rats served as controls ( n = 11). We used telemetry to measure BP and heart rate (HR), and acute ganglion blockade and air-jet stress to investigate possible control of BP by the sympathetic nervous system. In addition, we used myograph technique to study vascular function ex vivo. The INS and INS+LOS groups developed euglycemic hyperinsulinemia. Insulin did not affect BP but increased HR (27 beats/min on average). Ganglion blockade reduced mean arterial pressure (MAP) similarly in all groups. Air-jet stress did not increase sympathetic reactivity but rather revealed possible blunting of the stress response in hyperinsulinemia. Chronic losartan markedly reduced 24-h-MAP in the INS+LOS group (−38 ± 1 mmHg P < 0.001) compared with the LOS group (−18 ± 1 mmHg, P ≤ 0.05). While insulin did not affect vascular function per se, losartan improved endothelial function in the aorta of insulin-treated rats. Our results raise doubt regarding the role of hyperinsulinemia in hypertension. Moreover, we found no evidence that insulin affects sympathetic nervous system activity. However, chronic losartan treatment revealed an important interaction between insulin and RAAS in BP control.
Identification of intestinal bicarbonate transporters involved in formation of carbonate precipitates to stimulate water absorption in marine teleost fish
Authors: Kurita Yukihiro , Nakada Tsutomu , Kato Akira , Doi Hiroyuki , Mistry Abinash C. , Chang Min-Hwang , Romero Michael F. , Hirose Shigehisa
Published: January 2008

Marine teleost fish precipitate divalent cations as carbonate deposits in the intestine to minimize the potential for excessive Ca2+entry and to stimulate water absorption by reducing luminal osmotic pressure. This carbonate deposit formation, therefore, helps maintain osmoregulation in the seawater (SW) environment and requires controlled secretion of HCO3−to match the amount of Ca2+entering the intestinal lumen. Despite its physiological importance, the process of HCO3−secretion has not been characterized at the molecular level. We analyzed the expression of two families of HCO3−transporters, Slc4 and Slc26, in fresh-water- and SW-acclimated euryhaline pufferfish, mefugu ( Takifugu obscurus), and obtained the following candidate clones: NBCe1 (an Na+-HCO3−cotransporter) and Slc26a6A and Slc26a6B (putative Cl−/HCO3−exchangers). Heterologous expression in Xenopus oocytes showed that Slc26a6A and Slc26a6B have potent HCO3−-transporting activity as electrogenic Cl−/ nHCO3−exchangers, whereas mefugu NBCe1 functions as an electrogenic Na+- nHCO3−cotransporter. Expression of NBCe1 and Slc26a6A was highly induced in the intestine in SW and expression of Slc26a6B was high in the intestine in SW and fresh water, suggesting their involvement in HCO3−secretion and carbonate precipitate formation. Immunohistochemistry showed staining on the apical (Slc26a6A and Slc26a6B) and basolateral (NBCe1) membranes of the intestinal epithelial cells in SW. We therefore propose a mechanism for HCO3−transport across the intestinal epithelial cells of marine fish that includes basolateral HCO3−uptake (NBCe1) and apical HCO3−secretion (Slc26a6A and Slc26a6B).
Treating lithium-induced nephrogenic diabetes insipidus with a COX-2 inhibitor improves polyuria via upregulation of AQP2 and NKCC2
Authors: Kim Gheun-Ho , Choi Nak Won , Jung Ju-Young , Song Ji-Hyun , Lee Chang Hwa , Kang Chong Myung , Knepper Mark A.
Published: January 2008

Prostaglandin E2may antagonize vasopressin-stimulated salt absorption in the thick ascending limb and water absorption in the collecting duct. Blockade of prostaglandin E2synthesis by nonsteroidal anti-inflammatory drugs (NSAIDs) enhances urinary concentration, and these agents have antidiuretic effects in patients with nephrogenic diabetes insipidus (NDI) of different etiologies. Because renal prostaglandins are derived largely from cyclooxygenase-2 (COX-2), we hypothesized that treatment of NDI with a COX-2 inhibitor may relieve polyuria through increased expression of Na-K-2Cl cotransporter type 2 (NKCC2) in the thick ascending limb and aquaporin-2 (AQP2) in the collecting duct. To test this hypothesis, semiquantitative immunoblotting and immunohistochemistry were carried out from the kidneys of lithium-induced NDI rats with and without COX-2 inhibition. After male Sprague-Dawley rats were fed an LiCl-containing rat diet for 3 wk, the rats were randomly divided into control and experimental groups. The COX-2 inhibitor DFU (40 mg·kg−1·day−1) was orally administered to the experimental rats for an additional week. Treatment with the COX-2 inhibitor significantly relieved polyuria and raised urine osmolality. Semiquantitative immunoblotting using whole-kidney homogenates revealed that COX-2 inhibition caused significant increases in the abundance of AQP2 and NKCC2. Immunohistochemistry for AQP2 and NKCC2 confirmed the effects of COX-2 inhibition in lithium-induced NDI rats. The upregulation of AQP2 and NKCC2 in response to the COX-2 inhibitor may underlie the therapeutic mechanisms by which NSAIDs enhance antidiuresis in patients with NDI.
Effects of febuxostat on metabolic and renal alterations in rats with fructose-induced metabolic syndrome
Authors: Sánchez-Lozada Laura G. , Tapia Edilia , Bautista-García Pablo , Soto Virgilia , Ávila-Casado Carmen , Vega-Campos Iliana P. , Nakagawa Takahiko , Zhao Lin , Franco Martha , Johnson Richard J.
Published: January 2008

Increased fructose consumption is associated with hyperuricemia, metabolic syndrome, and renal damage. This study evaluated whether febuxostat (Fx), an investigational nonpurine, and selective xanthine oxidase inhibitor, could alleviate the features of metabolic syndrome as well as the renal hemodynamic alterations and afferent arteriolopathy induced by a high-fructose diet in rats. Two groups of rats were fed a high-fructose diet (60% fructose) for 8 wk, and two groups received a normal diet. For each diet, one group was treated with Fx (5–6 mg·kg−1·day−1in the drinking water) during the last 4 wk (i.e., after the onset of metabolic syndrome), and the other received no treatment (placebo; P). Body weight was measured daily. Systolic blood pressure and fasting plasma uric acid (UA), insulin, and triglycerides were measured at baseline and at 4 and 8 wk. Renal hemodynamics and histomorphology were evaluated at the end of the study. A high-fructose diet was associated with hyperuricemia, hypertension, as well as increased plasma triglycerides and insulin. Compared with fructose+P, fructose+Fx rats showed significantly lowered blood pressure, UA, triglycerides, and insulin ( P < 0.05 for all comparisons). Moreover, fructose+Fx rats had significantly reduced glomerular pressure, renal vasoconstriction, and afferent arteriolar area relative to fructose+P rats. Fx treatment in rats on a normal diet had no significant effects. In conclusion, normalization of plasma UA with Fx in rats with metabolic syndrome alleviated both metabolic and glomerular hemodynamic and morphological alterations. These results provide further evidence for a pathogenic role of hyperuricemia in fructose-mediated metabolic syndrome.
Acid, basic, and neutral peptidases present different profiles in chromophobe renal cell carcinoma and in oncocytoma
Authors: Blanco Lorena , Larrinaga Gorka , Pérez Itxaro , López José I. , Gil Javier , Agirregoitia Ekaitz , Varona Adolfo
Published: January 2008

Renal cell carcinomas (RCCs) are neoplasias with high prevalence and mortality. We previously reported that several peptidases may be involved in the pathophysiology of clear cell renal cell carcinoma (CCRCC). Now, to gain insight into the reasons that lead the various RCC types to behave very differently with regard to aggressiveness and response to anticancer treatments, we analyzed subsets of chromophobe renal cell carcinoma (ChRCC), and renal oncocytoma (RO), a benign tumor; as well as different grades and stages of CCRCCs. Particulate APN, APB, and APA activities were decreased in both ChRCC and RO (tumor vs. nontumor tissues). Interestingly, activities were downregulated in a tumor-type specific way and the intensities of the decreases were stronger in the benign tumor than in the malignant type. Moreover, when two key histopathological parameters for tumor prognosis (high vs. low stage and grade) were analyzed, increases of activity were also observed in several of these cell surface peptidases (APN, APB). Some soluble activities (APB, Asp-AP) were also downregulated in the RCCs. With respect to genetic expression, PSA and APN were in a positive correlation related to their activities in both ChRCC and RO; but not APB, Asp-AP, APA, and PGI. These results may suggest an involvement of several peptidases in the pathophysiology of renal cancer, since they presented different patterns of activity and expression in tumors with different behaviors.
Functional polymorphisms in inbred rat strains and their allele frequencies in commercially available outbred stocks
Authors: Kuramoto Takashi , Nakanishi Satoshi , Serikawa Tadao
Published: January 2008

Polymorphisms that have been proven to influence gene functions are called functional polymorphisms. It is significant to know the distribution of functional polymorphisms in the rat, widely used in animal models for human diseases. In this study, we assessed 16 functional polymorphisms consisting of 3 coat color and 13 disease-associated genes in 136 rat strains, as a part of the genetic profiling program of the National Bio Resource Project for the Rat (NBRP-Rat). Polymorphisms of Cdkn1a, Fcgr3, Grp10, Lss, and Fdft1, which were proven to function in prostate tumorigenesis, glomerulonephritis, hyperphagia, and cholesterol biosynthesis, were shared among various inbred strains. These findings indicated that most rat strains harbored the disease-associated alleles and suggested that many unidentified functional polymorphisms might exist in inbred rat strains. The functional polymorphisms shared in inbred strains were also observed within outbred stocks available commercially. Therefore, this implies that experimental plans based on either rat inbred strains or outbred stocks need to be carefully designed with a full understanding of the genetic characteristics of the animals. To select the most suitable strains for experiments, the NBRP-Rat will periodically improve and update the genetic profiles of rat strains.
Exact Interior Reconstruction with Cone‐Beam CT
Authors: Ye Yangbo , Yu Hengyong , Wang Ge
Published: January 2008

Using the backprojection filtration (BPF) and filtered backprojection (FBP) approaches, respectively, we prove that with cone‐beam CT the interior problem can be exactly solved by analytic continuation. The prior knowledge we assume is that a volume of interest (VOI) in an object to be reconstructed is known in a subregion of the VOI. Our derivations are based on the so‐called generalized PI‐segment (chord). The available projection onto convex set (POCS) algorithm and singular value decomposition (SVD) method can be applied to perform the exact interior reconstruction. These results have many implications in the CT field and can be extended to other tomographic modalities, such as SPECT/PET,
MRI.
Generalized Nonlinear Variational Inclusions Involving "Equation missing" -Monotone Mappings in Hilbert Spaces
Authors: Cho Yeol Je , Qin Xiaolong , Shang Meijuan , Su Yongfu
Published: January 2008

A new class of generalized nonlinear variational inclusions involving "Equation missing"-monotone mappings in the framework of Hilbert spaces is introduced and then based on the generalized resolvent operator technique associated with "Equation missing"-monotonicity, the approximation solvability of solutions using an iterative algorithm is investigated. Since "Equation missing"-monotonicity generalizes "Equation missing"-monotonicity and "Equation missing"-monotonicity, results obtained in this paper improve and extend many others.