bluuebunny/crossref_metadata_2025 huggingface dataset:
Developing a Raman Spectral Method for Measuring the Strontium and Calcium Concentrations of Fish Otoliths
Authors: Gauldie R.W. , Xi K. , Sharma S.K.
Published: June 2008

Surface-enhanced Raman scattering (SERS) spectra of Ca2+ and Sr2+ complexes of four dyes (O-cresolphthalein, PAN black, murexide, and eriochrome-black T(EBT) are reported. It has been demonstrated that SERS spectra of the murexide complex of Ca2+ can be used for the accurate determination of the cation in solutions at pH 12–8. Similarly, the SERS spectra of the EBT complex of Sr2+ can yield accurate determination of the cation concentration in solutions at pH 12–8. The SERS technique has linear resolutions of Sr2+ and Ca2+ concentrations down to 219 and 20 ppb, respectively. The chemistry of the otoliths of Hyperoglyphe antarctica (Centrolophidae: Teleostei) and Beryx splendens (Berycidae: Teleostei) proved to be similar. Using the SERS murexide complex technique for Ca and the SERS EBT complex for Sr, concentrations were 39.33% weight Ca and 272.7 ppm Sr for H. antarctica and 44.93% weight Ca and 273.133 ppm Sr for B. splendens.
Liver Glycogen, Enzyme Activities, and Pancreatic Hormones in Juvenile Atlantic Salmon (Salmo salar) during Their First Summer in Seawater
Authors: Plisetskaya Erika M. , Moon Thomas W. , Larsen Donald A. , Foster Glen D. , Dickhoff Walton W.
Published: June 2008

Our observation of very low liver glycogen concentration in 1-yr-old feeding Atlantic salmon (Salmo salar) in seawater net-pens in Puget Sound, Washington, led to studies of their metabolic status. We assessed liver glycogen concentration, activities of some hepatic enzymes involved in glycogen synthesis, depletion, and gluconeogenesis, and plasma profiles of glucose and pancreatic hormones (insulin and glucagon) in yearling Atlantic salmon before and after seawater transfer. Liver glycogen concentration in Atlantic salmon during the several months after seawater entry was much lower than in coho salmon (Oncorhynchus kisutch) of the same age in seawater. Other metabolic and hormonal indices throughout the study did not differ substantially between the two species. During their first summer in seawater net-pens, seemingly healthy, feeding 1-yr-old Atlantic salmon smolts are prone to high mortality. We hypothesize that the virtual absence of glycogen reserves in the liver makes seawater-adapted 1-yr-old Atlantic salmon juveniles particularly susceptible to stress and may contribute to high summer mortality.
Homing, Straying, and Gene Flow among Seasonally Separated Populations of Chum Salmon (Oncorhynchus keta)
Authors: Tallman Ross F. , Healey Michael C.
Published: June 2008

To test the hypothesis that salmonids that stray into established populations can successfully reproduce, we compared the spatial and temporal pattern of return of marked individuals with the pattern of gene flow suggested by electrophoretic analysis in three populations of chum salmon (Oncorhynchus keta) on Vancouver Island. Substantial straying occurred between populations that spawned during the same season. Populations where there was both spatial and temporal isolation in spawning had little straying. Electrophoretic analysis suggested that gene flow was substantially lower than the rate of straying and that it was highest among populations in close geographic proximity. The results of analysis using a log-linear model showed that the probability of discovering an individual stray was dependent on the population sampled and whether one sampled by mark–recapture or using biochemical genetic analysis. We propose that the difference between the rate of straying as measured by mark–recapture and by the analysis of polymorphic enzymes could be accounted for if salmonids straying onto the spawning grounds of established populations of conspecifics had lower reproductive success than fish that return to their natal streams.
Simple Size-Structured Models of Recruitment and Harvest in Pacific Salmon (Oncorhynchusspp.)
Authors: Forbes L. Scott , Peterman Randall M.
Published: June 2008

Growing evidence suggests that in Pacific salmon (Oncorhynchus spp.), components of reproductive success besides fecundity are size dependent. However, managers setting escapement goals usually estimate reproductive potential of a stock in terms of total number of spawners, number of female spawners, or potential egg deposition given a mean size of spawners. Interannual variation in size composition of spawners may thus result in errors in assessing reproductive potential. Here, we develop models of recruitment and harvest and determine optimal size-selective harvesting strategies. These optimal strategies range from the current large-fish harvests (larger-than-average fish are caught, leaving smaller fish to spawn) to small-fish harvests, where the reverse is true. If the body mass (M) of individual spawners increases more rapidly than reproductive success (RS) with respect to increasing length of adult females (e.g., if number of eggs alone best measures RS), then sustainable biomass yield is maximized by the current large-fish harvest. However, if RS/M increases with increasing length of females (e.g., if total biomass of eggs best measures RS), then small-fish harvest maximizes sustainable yield. Evidence suggests that some salmon populations show this latter pattern; thus, large-fish harvests may generate suboptimal yields.
Assessment of Fin Erosion by Comparison of Relative Fin Length in Hatchery and Wild Trout in Utah
Authors: Bosakowski Thomas , Wagner Eric J.
Published: June 2008

We measured all fins of 600 hatchery trout sampled from all 10 state fish hatcheries in Utah, and of wild fish sampled as controls comprising 58 rainbow trout (Oncorhynchus mykiss), 33 cutthroat trout (O. clarki), and 54 brown trout (Salmo trutta). A strong linear correlation was found between fin length and total body length (100–300 mm) for all fins of wild rainbow trout. "Relative fin length" (fin length/total body length × 100) proved to be a useful comparative measure, as this statistic was not biased by fish length in the wild fish sampled (all slopes <0.01%). Interspecific comparison of wild rainbow, cutthroat, and brown trout showed slight but statistically significant differences in some fin lengths. In intraspecific comparisons, hatchery fish had significantly shorter (10–50%) rayed fins than wild fish. The dorsal fin was most severely eroded in rainbow and brown trout, followed by the pectoral, anal, ventral, and caudal fins, in cutthroat trout the pattern was the same except that pectoral fins had more extensive erosion than dorsal fins. No species was clearly more susceptible to fin erosion in hatcheries, but the Fish Lake – DeSmet strain of rainbow trout had significantly shorter fins than other rainbow trout strains.
Development and Evaluation of a Biological Model to Assess Regional-Scale Effects of Acidification on Atlantic Salmon (Salmo salar)
Authors: Korman Josh , Marmorek David R. , Lacroix Gilles L. , Amiro Peter G. , Ritter John A. , Watt Walton D. , Cutting Richard E. , Robinson Donald C. E.
Published: June 2008

We developed an age-structured simulation model incorporating pH-dependent mortality to assess impacts of acidification on Atlantic salmon (Salmo salar) populations at the reach and river system level. Applied to the LaHave River, Nova Scotia, acidic reaches (mean annual pH 4.6–5.1) were predicted to have 0–15% of the annual smoit production and 0–31% of the maiden spawner production compared with circumneutral reaches (pH ≥ 5.6) and increased juvenile growth due to lower parr densities. The benefit of increased growth (earlier age of smoltification and increased early marine survival) was not sufficient to outweigh impacts of higher freshwater juvenile mortality. Simulated removal of acidic conditions resulted in a 41% increase in recruits, but only after several decades following complete chemical recovery. Circumneutral reaches were predicted to be 4–12 times more efficient at producing smolts and 3–7 times more efficient at producing adults from hatchery fingerlings compared with acidic reaches. To maintain current target egg deposition rates of 240 eggs/100 m2, circumneutral reaches could withstand grilse exploitation rates of up to 65%, while acidic reaches, even without harvesting mortality, could not maintain this level. Fisheries management strategies need to account for variability in freshwater production both within and between river systems.
Particle-size-conversion Efficiency, Invertebrate Production, and Potential Fish Production in Lake Ontario
Authors: Borgmann U. , Whittle D. M.
Published: June 2008

The relationships between body size and p,p′-DDE and total PCB concentration in Zooplankton, mysids, amphipods, slimy sculpin (Cottus cognatus), rainbow smelt (Osmerus mordax), alewife (Alosa pseudo-harengus), and lake trout (Salvelinus namayeush) in Lake Ontario were determined for samples collected from 1989 to 1992. Amphipods, and to a lesser extent sculpins, had higher DDE and PCB concentrations than predicted from the contaminant concentration – body size relationship for the pelagic species. PCB, but not DDE, concentrations in Zooplankton were also abnormally high. For the pelagic species, excluding PCB concentrations in Zooplankton, the log contaminant concentration – log body size relationship had a slope of 0.23 (95% confidence limits = ±0.014). Combined with revised estimates of the efficiency of contaminant retention from one body size to another (ε′ = 0.05–0.10), the revised estimate of particle-size-conversion efficiency (ε) for Lake Ontario falls between 0.27 and 0.35. Recent estimates of invertebrate (Zooplankton, mysid, and amphipod) annual production average 18 g/m2 (dry weight) with upper and lower limit estimates of 14–27 g/m2. Using ε to extrapolate from invertebrate to fish production results in estimates of mean potential fish production in Lake Ontario of 1–7 kg/ha (wet weight), as compared with previously published estimates of 6 and 14 kg/ha.
Calculation of Bayes Posterior Probability Distributions for Key Population Parameters
Authors: Walters Carl , Ludwig Donald
Published: June 2008

The Bayes posterior probability distribution is a powerful way to represent uncertainty in fisheries stock assessments, and can be calculated for key population and policy parameters of practically any population dynamics model. But the calculation is unwieldy when probabilities are to be assigned to a large grid of parameter combinations. The computational burden can be reduced substantially by analytically integrating over at least two "nuisance parameters" that occur in most assessment models: the observation error variance and the catchability coefficient. This simplification allows the analyst and manager to focus more easily on population parameters (stock size, slope of recruitment curve) that are of direct policy interest.
Remote Sensing in Fisheries: A Tool for Better Management in the Utilization of a Renewable Resource
Authors: Simpson James J.
Published: June 2008

A framework is developed for the interactions among the diverse groups involved in operational fisheries oceanography: fishing industry, basic and operational researchers, and tactical and strategic stock assessment managers. The basis for these interactions is the need for accurate and timely information, information so complex and diverse that no single sector of the community can efficiently and economically satisfy its own information requirements. Some presently available remotely-sensed data and analysis methods that have potential for providing part of the required information are presented. Projections of future capabilities in this area also are made. The increased use of Geographical Information Systems (GIS) and near-real-time communication networks among the various sectors of the community also is discussed.
The long-term stability of a cutting slope in an overconsolidated sensitive clay
Authors: Silvestri Vincenzo
Published: June 2008

In the design of two 7 m high road cuttings in an overconsolidated sensitive clay in the Lachute region in Quebec, a slope inclination of 2.5:1 was retained for long-term stability. The minimum anticipated factor of safety against long-term failure was equal to 1.28 and was based on the postpeak strength parameters c′ = 7 kPa and [Formula: see text], which are typical of the Champlain Sea clays. Following a series of failures in the southern slope of one of the cuttings, only 1.5 years after their construction, a postslide analysis was performed using the critical stress curve method. The results of the analysis yielded the shear strength parameters [Formula: see text]and [Formula: see text]. It is believed that the surprisingly small cohesion intercept at the time of failure found in this study is due to the fissured nature of the clay, the spreading of the discontinuities caused by stress relief following excavation, and subsequent desiccation of the exposed clay mass.
Effects of a pipeline right-of-way on sediment yields in the Spring Creek watershed, Alberta
Authors: Martz Lawrence W. , Campbell Ian A.
Published: June 2008

Very few data are available on the sediment yield of Alberta watersheds especially in the northern portion of the province. In the 175 000 km2 Peace River basin, which covers about 25% of Alberta, sediment data are collected regularly at only four stations. One of these is the 112.7 km2 Spring Creek watershed. In 1977 a pipeline was installed near the mouth of Spring Creek, disturbing an area of about 5000 m2 near the stream channel. The effects of this were to increase local sediment yields by over 1600 Mg in a 4 month period. This compares with regional averages for the Peace River basin of 18–88 Mg∙km−2∙year−1. The study indicates the magnitude of spatial variation of sediment production and shows some effects of geotechnical activities on sediment yields.
Comparison of undrained shear strength results obtained by different test methods in soft clays
Authors: Eden W. J. , Law K. T.
Published: June 2008

The Cambridge self-boring pressuremeter and the Norwegian Geotechnical Institute field vane apparatus have been used at three sites of different subsoils. Two of the sites, South Gloucester and National Research Council of Canada grounds, are located in Leda clay in the Ottawa area. The third site features a highly plastic lacustrine clay in northwestern Quebec. At this site tests were conducted beside and under a fill that had undergone 1 m of surface settlement. At all three sites, the pressuremeter yields higher strengths than the field vane apparatus.Conventional and special laboratory tests were conducted on large diameter tube or block samples from South Gloucester. It is found that the conventional triaxial compressive strength is intermediate between the pressuremeter and field vane strengths. In accounting for the strength discrepancy, factors such as anisotropy, stress path, and disturbance have been studied in the light of the results of the special tests.
Pore pressure parameters for unsaturated soils
Authors: Hasan J. U. , Fredlund D. G.
Published: June 2008

The concept of pore pressure parameters has been found convenient to visualize the pore pressure response of saturated soils for various applied stress changes. This paper derives pore pressure parameters that can be utilized in determining the pore pressure response of unsaturated soils. The expressions derived for the estimation of pore-air and pore-water pressures under undrained, isotropic loading are called the Ba and Bw pore pressure parameters. Measured pore pressures are compared with predicted values. Various factors influencing the proposed pore pressure parameters are discussed.Pore pressure parameter expressions are also derived for the pore-air and pore-water pressures induced as a result of deviator stress changes during undrained loading (i.e., Aa and Aw).
The behaviour of friction piles in ice and ice-rich soils
Authors: Morgenstern N. R. , Roggensack W. D. , Weaver J. S.
Published: June 2008

A comprehensive review of long-term creep tests on ice has been undertaken and a flow law for ice has been proposed. Creep tests on ice-rich soils have also been reviewed, and it is concluded that the flow law for ice constitutes an upper bound to these test data. Using this flow law, pile velocities in ice and ice-rich soils have been predicted and the predictions are shown to be in good agreement with available long-term creep data for piles in ice and ice-rich soils.
Design, construction, and performance of a pneumatic seal for closed system piezometers
Authors: Tao S. S. , Guenter D. M. , Snodgrass L. J.
Published: June 2008

A pneumatic seal has been developed to convert 50.8 mm standpipes to closed-system piezometers utilizing commercially available pneumatic transducer piezometers. This sealing system permits retrieval of the piezometers for recalibration or reuse elsewhere. A nonreinforced inflated rubber membrane seal was found to be satisfactory in soils of medium to high permeability and moderate piezometer pressures. A mesh-reinforced rubber membrane seal was found to be much superior and reduced the reaction of the seal to changed hydraulic pressures to unmeasurably small movements. This gave the piezometer better compliance characteristics making the system suitable for measuring relatively small pressure changes in soils of low permeability. Design and construction details of the nonreinforced membrane seal and mesh-reinforced membrane seal are presented. Field response times and operating pressures are discussed.
Hydraulic fracture in earth and rock-fill dams
Authors: Lo K. Y. , Kaniaru Kiny
Published: July 2008

Unsatisfactory performance of earth and rock-fill dams involving excessive seepage, piping or failure has been attributed to hydrofracture of the core. Although the phenomenon has been reported for some time, important factors influencing hydraulic fracturing pressure, such as saturation and consolidation, have received relatively little attention; nor have results of laboratory tests or theoretical study been directly related to field performance. In this paper, laboratory hydrofracturing tests under well-defined conditions were performed. A simple theoretical expression for fracture pressure is developed involving only conventional soil strength parameters. Case histories involving hydraulic fracturing of the earthcore are reviewed, and "field" hydraulic fracture pressure and crack closure pressure are defined. The results of the laboratory tests show that hydraulic fracture pressure is not a unique soil property; its value depends on the degree of saturation and consolidation. A comparison of the data deduced from case records with test results and theoretical predictions indicates general consistency. The field hydraulic fracturing pressures are bounded in the upper limit by results from saturated-consolidated tests and in the lower limit by results of saturated–unconsolidated hydraulic fracturing tests. It is suggested that the methodology presented may be useful in the assessment of risk of hydraulic fracturing of dams. Key words: earth and rock-fill dams, hydraulic fracture, tensile strength, seepage, Teton Dam.
The impact of synthetic leachate on the hydraulic conductivity of a smectitic till underlying a landfill near Saskatoon, Saskatchewan
Authors: Yanful Ernest K. , Haug Moir D. , Wong Lionel C.
Published: July 2008

The impact of leachate on the hydraulic conductivity, k, of a glacial till used in the contraction of a liner for a landfill near Saskatoon, Saskatchewan, is evaluated. Low-gradient triaxial permeability testing of the water-moulded till over a 7-month period with six pore volumes of test leachate at a hydraulic gradient of approximately 100 gave a hydraulic conductivity of 3.0 × 10−9 cm/s, compared with 6.0 × 10−9 cm/s for the water-permeated sample at the same gradient. The k was also evaluated at gradients of 20 and 50 during water permeation and found to be 8.0 × 10−9 and 6.8 × 10−9 cm/s, respectively. The slight decrease in k with increase in gradient was attributed to a decrease in void ratio, resulting from a net increase in applied effective stress at the outflow end of the specimen. An assessment of the clay mineral composition of the till at the end of permeability testing did not show collapse of the smectite peak. Instead, the leachate appeared to have actually enhanced the smectite peak relative to the illite peak. It was concluded that the leachate did not have any detrimental impact on the till and that the hydraulic conductivity "of the 0.3-m-thick liner underlying the landfill may not be expected to increase as a result of interaction with leachate. Key words: leachate, soil liners, hydraulic conductivity, smectitic till, X-ray diffraction, triaxial permeability testing.
Effects of bigleaf maple on soils in Douglas-fir forests
Authors: Fried Jeremy S. , Boyle James R. , Tappeiner II John C. , Cromack Jr. Kermit
Published: July 2008

Soil chemical and physical properties, forest floor weights, nutrient content and turnover rates, and litter fall weights and nutrient content under bigleaf maple (Acermacrophyllum Pursh) and Douglas-fir (Pseudotsugamenziesii (Mirb.) Franco var. menziesii) were compared on five sites on the eastern margin of the Oregon Coast Range. Litter fall weight and nutrient content were significantly greater under maple on every site for every macronutrient and for most micronutrients. Forest floor biomass and nutrient content were extremely variable, much more so than litter fall, and there were no consistent differences between the two species. However, turnover rates for forest floor biomass and nutrients were significantly faster under maple for every nutrient at every site. Bulk density of mineral soil was also highly variable with significant differences at only two sites. Soil under maple was consistently higher in nitrogen, and less consistently, in potassium. There were no consistent trends in amounts of calcium, magnesium, or phosphorus. Soil organic carbon content under maple was significantly greater than under Douglas-fir on four of five sites. These differences may result from the more rapid turnover of forest floors under maple trees.
Wind speed and snow evaporation in a stand of juvenile lodgepole pine in Alberta
Authors: Bernier Pierre Y.
Published: July 2008

Wind speed and snow evaporation were measured in a small artificial stand of 2.5-m lodgepole pines and in an adjacent field during the winter of 1987. Stand densities of 2500, 1650, and 800 stems/ha were obtained through periodic removal of trees. The reduction of wind speed brought about by the trees is a linear function of [Formula: see text], the angle of view from the anemometer to the tops of the surrounding trees. When the stand was at full density, snow evaporation was about one-third of that measured in the open field, and when stand density was reduced to 1650 stems/ha, snow evaporation was equal to that of the open field. Because of high melt rates, no data were obtained from the lowest stand density. The results are summarized in a predictive relation between the angle of view [Formula: see text] and the reduction in snow evaporation caused by the trees.
Source distances for coarse woody debris entering small streams in western Oregon and Washington
Authors: McDade M. H. , Swanson F. J. , McKee W. A. , Franklin J. F. , Sickle J. Van
Published: July 2008

Coarse woody debris from streamside forests plays important biological and physical roles in stream ecosystems. The distance from stream bank to rooting site was determined for at least 30 fallen trees at each study site on 39 streams in the Cascade and Coast ranges of Oregon and Washington. The study sites varied in channel size (first- through third-order), side-slope steepness (3 to 40°), and age of surrounding forest (mature or old-growth stands). The distribution of distances from rooting site to bank was similar among streams, with 11% of the total number of debris pieces originating within 1 m of the channel and over 70% originating within 20 m. Stands with taller trees (old-growth conifers) contributed coarse woody debris to streams from greater distances than did stands with shorter (mature) trees.
Tissue-specific expression of PPAR mRNAs in diabetic rats and divergent effects of cilostazol
Authors: Wang Furong , Gao Ling , Gong Bendi , Hu Jianting , Li Mei , Guan Qingbo , Zhao Jiajun
Published: July 2008

Cilostazol and ligands of peroxisome proliferator-activated receptors (PPARs) have been effectively used to alleviate diabetic complications, but the common and tissue-specific expression patterns of PPARs in different tissues in diabetic patients and those treated with cilostazol have not been reported. Here, we aimed to assess the effects of diabetes and cilostazol on mRNA expression of PPARα and PPARγ in the aorta, renal cortex, and retina of diabetic rats treated with cilostazol for 8 weeks. PPARα mRNA expression showed uniform downregulation in all these tissues in diabetic rats, and this effect was reversed by cilostazol treatment. Surprisingly, PPARγ mRNA expression was reduced in the renal cortex and retina, yet increased in the aorta of diabetic rats, although cilostazol still reversed these changes. Interestingly, cilostazol, a well-known phosphodiesterase 3 inhibitor and cAMP elevator, augmented cAMP content only in the aorta, but showed no significant effects in the renal cortex of diabetic rats. In conclusion, mRNA expression of PPARs is tissue-specific in diabetes and may be differently affected by cilostazol, possibly because of its tissue-specific effects on cAMP content.
Overexpression of eNOS prevents the development of renovascular hypertension in mice
Authors: Gava Agata L. , Peotta Veronica A. , Cabral Antonio M. , Vasquez Elisardo C. , Meyrelles Silvana S.
Published: July 2008

Gene therapy has become an important tool for understanding several cardiovascular diseases. In the present study we investigated the effects of endothelial nitric oxide synthase (eNOS) overexpression on renovascular hypertension. Experiments were carried out in C57BL/6 mice randomly assigned to either a two-kidney one-clip (2K1C) hypertension group or a sham-operated group. At the same time surgery was carried out, both 2K1C and sham mice received an intravenous injection of recombinant adenovirus expressing the functional gene eNOS or the reporter gene β-galactosidase (β-gal). Fourteen days later, arterial pressure, baroreflex sensitivity, and cardiac sympathetic and parasympathetic tone were evaluated in conscious mice. Measurement of mean arterial pressure showed arterial hypertension in 2K1C-βgal mice compared with sham-βgal mice (121 ± 3 vs. 96 ± 2 mm Hg, p < 0.01), which was prevented by eNOS overexpression (2K1C-eNOS 100 ± 4 vs. sham-eNOS 99 ± 3 mm Hg). Linear regression analysis of the reflex tachycardia response to sodium nitroprusside-induced hypotension showed that baroreflex sensitivity was significantly attenuated in 2K1C-βgal mice (5.8 ± 0.5 vs. sham-βgal 8.0 ± 0.8 beats·min–1·mm Hg–1, p < 0.05), but this decrease was not prevented by eNOS overexpression (2K1C-eNOS 7.2 ± 0.5 vs. sham-eNOS 8.8 ± 0.7 beats·min–1·mm Hg–1, p < 0.05). The cardiac sympathetic tone was augmented and the vagal tone was reduced in 2K1C-βgal (152 ± 17 and 45 ± 12 beats·min–1, respectively) compared with sham-βgal mice (112 ± 6 and 89 ± 7 beats·min–1, respectively), and similar results were observed in 2K1C-eNOS mice compared with sham-eNOS. The data indicate that eNOS overexpression was able to prevent the development of 2K1C renovascular hypertension in mice, without affecting other characteristic cardiovascular dysfunctions.
Inhibitory effects of astragaloside IV on ovalbumin-induced chronic experimental asthma
Authors: Du Qiang , Chen Zhen , Zhou Lin-fu , Zhang Qian , Huang Mao , Yin Kai-sheng
Published: July 2008

Astragaloside IV, a new cycloartane-type triterpene glycoside extract of Astragalus membranaceus Bunge, has been identified for its potent immunoregulatory, antiinflammatory, and antifibrotic actions. Here we investigated whether astragaloside IV could suppress the progression of airway inflammation, airway hyperresponsiveness, and airway remodeling in a murine model of chronic asthma. BALB/c mice sensitized to ovalbumin (OVA) were chronically challenged with aerosolized OVA for 8 weeks. Astragaloside IV was orally administered at a dose of 50 mg·kg–1·day–1 during each OVA challenge. Astragaloside IV treatment resulted in significant reduction of eosinophilic airway inflammation, airway hyperresponsiveness, interleukin (IL)-4 and IL-13 levels in bronchoalveolar lavage fluid, and total immunoglobulin E levels in serum. Furthermore, astragaloside IV treatment markedly inhibited airway remodeling, including subepithelial fibrosis, smooth muscle hypertrophy, and goblet cell hyperplasia. In addition, the expression of transforming growth factor-β1 in the lung was also reduced by astragaloside IV. These data indicate that astragaloside IV may mitigate the development of characteristic features in chronic experimental asthma.
DAMAGE SPREADING ON THE HOMO- AND HETERO-CELL LATTICES WITH COMPETING GLAUBER AND KAWASAKI DYNAMICS
Authors: GUO Z. Z. , WU XIAO-WEI
Published: July 2008

The damage spreading of the Ising model on the homo- and hetero-cell lattices (here the topological hexagonal lattice and the 4–8 lattice) with competing Glauber (G-) and Kawasaki (K-) dynamics is studied and the results are compared. For the homo-cell lattice, we pay attention to the pure K-dynamics or the cases in which the K-dynamics is dominant. We get four main conclusions related to the K-dynamics through our calculations: (1) the damage always spreads as long as Kawasaki dynamics is dominant during the competition of two dynamics; (2) the relation for the saturation damage, 〈s〉∞ = 0.5, holds for K-dynamics whatever the updating rules are; (3) 〈s〉∞ = 0.5 is independent of the structures of the system; (4) the DS process under pure K-dynamics converges very slowly, especially for T = 0 K-dynamics. For the hetero-cell lattice, we are interested in the long-range interaction between spins and the different interaction strength for the spins in the hetero-cells. To include the long-range spin interaction, we consider the spin interactions up to next-nearest neighbors. It is shown that the inclusion of the next-nearest-neighbor interaction enhances the transition temperature greatly. The explanation and discussion for the results are presented.
COMPARATIVE STUDY OF DIELECTRIC BEHAVIOR OF Mn0.4Zn0.6Fe2O4 NANOFERRITE BY CITRATE PRECURSOR METHOD
Authors: MATHUR PREETI , THAKUR ATUL , SINGH M.
Published: July 2008

In the present work, comparative study of the dielectric behavior of Mn 0.4 Zn 0.6 Fe 2 O 4 ferrite synthesized with and without H 2 O 2 (hydrogen peroxide) has been presented. The dc resistivity has been improved by the citrate precursor method as compared to the ceramic method, and it is further improved by the addition of H 2 O 2, which acts as a strong oxidizing agent. We have shown by means of X-ray diffraction that the resulting ferrite is made up of nanocrystallites and the average size of these nanocrystallites–calculated by Scherrer's formula–depends on the polarizer. The average particle size was found to be ~70 nm with H 2 O 2 and ~88 nm without H 2 O 2. The particle size is further confirmed by scanning electron microscopy. Both the results are found to be in good agreement. The decrease in dielectric constant and dielectric loss factor by addition of oxidizing agent is justified by inverse proportionality between the resistivity and dielectric constant. Possible mechanisms contributing to these processes have been discussed.
QUANTUM GLASSINESS AND SUPERCONDUCTIVITY IN DOPED LOW DIMENSIONAL ANTIFERROMAGNETS
Authors: PANAGOPOULOS CHRISTOS
Published: July 2008

Following the direct observation of abrupt changes in the superconducting ground state in doped low dimensional antiferromagnets, we have identified a phase transition where superconductivity is optimal. The experiments indicate the presence of a putative quantum critical point associated with the emergence of a glassy state. This mechanism is argued to be an intrinsic property and as such, largely independent of material quality and the level of disorder.
ANALYSIS OF SPATIAL AND ENERGY SLOW TRAP PROFILE IN HfO2/SiO2 METAL-OXIDE-SILICON DEVICES BY LOW FREQUENCY NOISE MEASUREMENTS
Authors: ZAFARI LEILY , JOMAAH JALAL , GHIBAUDO GERARD , FAYNOT OLIVIER
Published: June 2008

A specific model for the low frequency (LF) noise in SiO 2/ HfO 2 metal-oxide-semiconductor devices on fully depleted silicon-on-insulator (FD-SOI) is proposed based on a proper spatial and energy slow trap profile. This model relates the spatial position of the probed traps with the applied vertical electric field in the gate dielectric via their energy distribution and thereby enables to explain the behaviour of LF noise regarding the front and back gate voltages. The dependence of the trap profile and thus the noise level on the interfacial layer thickness is also analysed by the model.
UNCONDITIONALLY SECURE COMPUTERS, ALGORITHMS AND HARDWARE, SUCH AS MEMORIES, PROCESSORS, KEYBOARDS, FLASH AND HARD DRIVES
Authors: KISH LASZLO B. , SAIDI OLIVIER
Published: June 2008

In the case of the need of extraordinary security, Kirchhoff-loop-Johnson-(like)-noise ciphers can easily be integrated on existing types of digital chips in order to provide secure data communication between hardware processors, memory chips, hard disks and other units within a computer or other data processor system. The secure key exchange can take place at the very first run and the system can renew the key later at random times with an authenticated fashion to prohibit man-in-the-middle attack. The key can be stored in flash memories within the communicating chip units at hidden random addresses among other random bits that are continuously generated by the secure line but are never actually used. Thus, even if the system is disassembled, and the eavesdropper can have direct access to the communication lines between the units, or even if she is trying to use a man-in-the-middle attack, no information can be extracted. The only way to break the code is to learn the chip structure, to understand the machine code program and to read out the information during running by accessing the proper internal ports of the working chips. However such an attack needs extraordinary resources and even that can be prohibited by a password lockout. The unconditional security of commercial algorithms against piracy can be provided in a similar way.
MODEL FOR THE MOTILITY OF FLAGELLATED BACTERIA
Authors: KIM JONG U.
Published: June 2008

Small flagellated bacteria cannot swim in a straight course due to rotational Brownian motion. By using Langevin equation and rotational diffusion equation we develop a model for the flagellated bacterial motion; thus, the model includes the rotational Brownian motion. Our model shows that the rotational Brownian motion is more significant at smaller turn angle during a tumble. It is also compared with experiment data.
STOCHASTIC RESONANCE IN SATURATION NONLINEARITIES BASED ON SIGNAL DETECTION
Authors: ZHANG LEI , HE JUN , SONG AIGUO
Published: June 2008

Recently, it was reported that some saturation nonlinearities could effectively act as noise-aided signal-noise-ratio amplifiers. In the letter we consider the signal detection performance of saturation nonlinearities driven by a sinusoidal signal buried in Gaussian white noise. It is showed that the signal detection statistics still undergo a nonmonotonic evolution as noise is raised. We also particularly show that an improvement of the SNR in terms of the first harmonic does not imply the possibility to improve the signal detection performance through stochastic resonance. The study might also complement other reports about stochastic resonance in saturation nonlinearities.
THEORY AND TECHNIQUES FOR VIBRATION-INDUCED CONDUCTIVITY FLUCTUATION TESTING OF SOILS
Authors: CHANG HUNG-CHIH , KISH LASZLO B. , KISHNÉ ANDREA SZ. , MORGAN CRISTINE L. S. , KWAN CHIMAN
Published: June 2008

First we present and theoretically analyze the phenomenological physical picture behind Vibration-Induced Conductivity Fluctuations. We identify the relevant tensors characterizing the electromechanical response against the vibrations for both longitudinal and transversal responses. We analyze the conductivity response with acceleration type vibrations and a new scheme, measurements with more advantageous compression type vibrations that are first introduced here. Compression vibrations provide sideband spectral lines shifted by the frequency of the vibration instead of its second harmonics; moreover the application of this method is less problematic with loose electrodes. Concerning geometry and electrodes, the large measurement errors in earlier experiment indicated electrode effects which justify using four-electrode type measurements. We propose and analyze new arrangements for the longitudinal and transversal measurements with both compression vibration and acceleration vibration for laboratory and field conditions.
EXACT SOLUTION FOR THE INTERIOR OF A BLACK HOLE
Authors: NIEUWENHUIZEN THEO M.
Published: June 2008

Within the Relativistic Theory of Gravitation it is shown that the equation of state p = ρ holds near the center of a black hole. For the stiff equation of state p = ρ − ρc the interior metric is solved exactly. It is matched with the Schwarzschild metric, which is deformed in a narrow range beyond the horizon. The solution is regular everywhere, with a specific shape at the origin. The gravitational redshift at the horizon remains finite but is large, z ~ 1023 M⊙/M. Time keeps its standard role also in the interior. The energy of the Schwarzschild metric, shown to be minus infinity in the General Theory of Relativity, is regularized in this setup, resulting in E = Mc2.
WEAKENED CONDITIONS OF ADMISSIBILITY OF SURFACE FORCES APPLIED TO LINEARLY ELASTIC MEMBRANE SHELLS
Authors: LUCE ROBERT , POUTOUS CÉCILE , THOMAS JEAN-MARIE
Published: July 2008

We consider a family of linearly elastic shells of the first kind (as defined in [2]), also known as non inhibited pure bending shells [7]. This family is indexed by the half-thickness ε. When ε approaches zero, the averages across the thickness of the shell of the covariant components of the displacement of the points of the shell converge strongly towards the solution of a "2D generalized membrane shell problem" provided the applied forces satisfy admissibility conditions [1,3]. The identification of the admissible applied forces usually requires delicate analysis.

In the first part of this paper, we simplify the general admissibility conditions when applied forces h are surface forces only, and obtain conditions that no longer depend on ε [5]: find hαβ = hαβ in L2(ω) such that for all η = (ηi) in V(ω), ∫ω hi ηi dω = ∫ω hαβγαβ(η)dω where ω is a domain of ℝ2, θ is in [Formula: see text] and [Formula: see text] is the middle surface of the shells, where (γαβ (η)) is the linearized strain tensor of S and V(ω) = {η ∈ H1(ω), η = 0 on γ0}, the shells being clamped along Γ0 = θ(γ0).

In the second part, since the simplified admissibility formulation does not allow to conclude directly to the existence of hαβ, we seek sufficient conditions on h for hαβ to exist in L2(ω). In order to get them, we impose more regularity to hαβ and boundary conditions. Under these assumptions, we can obtain from the weak formulation a system of PDE's with hαβ as unknowns. The existence of solutions depends both on the geometry of the shell and on the choice of h. We carry through the study of four representative geometries of shells and identify in each case a special admissibility functional space for h.
Developing and debugging algebraic specifications for Java classes
Authors: Henkel Johannes , Reichenbach Christoph , Diwan Amer
Published: July 2008

Modern programs make extensive use of reusable software libraries. For example, a study of a number of large Java applications shows that between 17% and 30% of the classes in those applications use container classes defined in the java.util package. Given this extensive code reuse in Java programs, it is important for the interfaces of reusable classes to be well documented. An interface is well documented if it satisfies the following requirements: (1) the documentation completely describes how to use the interface; (2) the documentation is clear; (3) the documentation is unambiguous; and (4) any deviation between the documentation and the code is machine detectable. Unfortunately, documentation in natural language, which is the norm, does not satisfy the above requirements. Formal specifications can satisfy them but they are difficult to develop, requiring significant effort on the part of programmers.

To address the practical difficulties with formal specifications, we describe and evaluate a tool to help programmers write and debug algebraic specifications. Given an algebraic specification of a class, our interpreter generates a prototype that can be used within an application like a regular Java class. When running an application that uses the prototype, the interpreter prints error messages that tell the developer in which way the specification is incomplete or inconsistent with a hand-coded implementation of the class. We use case studies to demonstrate the usefulness of our system.
Conditional functional dependencies for capturing data inconsistencies
Authors: Fan Wenfei , Geerts Floris , Jia Xibei , Kementsietsidis Anastasios
Published: July 2008

We propose a class of integrity constraints for relational databases, referred to as
conditional functional dependencies
(CFDs), and study their applications in data cleaning. In contrast to traditional functional dependencies (FDs) that were developed mainly for schema design, CFDs aim at capturing the consistency of data by enforcing bindings of semantically related values. For static analysis of CFDs we investigate
the consistency problem
, which is to determine whether or not there exists a nonempty database satisfying a given set of CFDs, and
the implication problem
, which is to decide whether or not a set of CFDs entails another CFD. We show that while any set of transitional FDs is trivially consistent, the consistency problem is NP-complete for CFDs, but it is in PTIME when either the database schema is predefined or no attributes involved in the CFDs have a finite domain. For the implication analysis of CFDs, we provide an inference system analogous to Armstrong's axioms for FDs, and show that the implication problem is coNP-complete for CFDs in contrast to the linear-time complexity for their traditional counterpart. We also present an algorithm for computing a minimal cover of a set of CFDs. Since CFDs allow data bindings, in some cases CFDs may be physically large, complicating the detection of constraint violations. We develop techniques for detecting CFD violations in SQL as well as novel techniques for checking multiple constraints by a single query. We also provide incremental methods for checking CFDs in response to changes to the database. We experimentally verify the effectiveness of our CFD-based methods for inconsistency detection. This work not only yields a constraint theory for CFDs but is also a step toward a practical constraint-based method for improving data quality.
Approximate continuous querying over distributed streams
Authors: Cormode Graham , Garofalakis Minos
Published: July 2008

While traditional database systems optimize for performance on one-shot query processing, emerging large-scale monitoring applications require continuous tracking of complex data-analysis queries over collections of physically distributed streams. Thus, effective solutions have to be simultaneously space/time efficient (at each remote monitor site), communication efficient (across the underlying communication network), and provide continuous, guaranteed-quality approximate query answers. In this paper, we propose novel algorithmic solutions for the problem of continuously tracking a broad class of complex aggregate queries in such a distributed-streams setting. Our tracking schemes maintain approximate query answers with provable error guarantees, while simultaneously optimizing the storage space and processing time at each remote site, and the communication cost across the network. In a nutshell, our algorithms rely on tracking general-purpose randomized sketch summaries of local streams at remote sites along with concise prediction models of local site behavior in order to produce highly communication- and space/time-efficient solutions. The end result is a powerful approximate query tracking framework that readily incorporates several complex analysis queries (including distributed join and multi-join aggregates, and approximate wavelet representations), thus giving the first known low-overhead tracking solution for such queries in the distributed-streams model. Experiments with real data validate our approach, revealing significant savings over naive solutions as well as our analytical worst-case guarantees.
Optimality of an algorithm solving the Bottleneck Tower of Hanoi problem
Authors: Dinitz Yefim , Solomon Shay
Published: July 2008

We study the Bottleneck Tower of Hanoi puzzle posed by D. Wood in 1981. There, a relaxed placement rule allows a larger disk to be placed
higher
than a smaller one if their size difference is less than a pregiven value
k
. A shortest sequence of moves (optimal algorithm) transferring all the disks placed on some peg in decreasing order of size, to another peg in the same order is in question. In 1992, D. Poole suggested a natural disk-moving strategy for this problem, and computed the length of the shortest move sequence under its framework. However, other strategies were overlooked, so the lower bound/optimality question remained open. In 1998, Benditkis, Berend, and Safro proved the optimality of Poole's algorithm for the first nontrivial case
k
= 2. We prove Poole's algorithm to be optimal in the general case.
Determining plurality
Authors: Alonso Laurent , Reingold Edward M.
Published: July 2008

Given a set of
n
elements, each of which is colored one of
c
colors, we must determine an element of the plurality (most frequently occurring) color by pairwise equal/unequal color comparisons of elements. We prove that (
c
− 1)(
n
−
c
)/2 color comparisons are necessary in the worst case to determine the plurality color and give an algorithm requiring (0.775
c
+ 5.9)
n
+
O
(
c
2
) color comparisons for
c
≥ 9.
Testing Euclidean minimum spanning trees in the plane
Authors: Czumaj Artur , Sohler Christian
Published: July 2008

Given a Euclidean graph
G
over a set
P
of
n
points in the plane, we are interested in verifying whether
G
is a Euclidean minimum spanning tree (EMST) of
P
or
G
differs from it in more than ϵ
n
edges. We assume that
G
is given in adjacency list representation and the point/vertex set
P
is given in an array. We present a property testing algorithm that accepts graph
G
if it is an EMST of
P
and that rejects with probability at least 2/3 if
G
differs from every EMST of
P
in more than ϵ,
n
edges. Our algorithm runs in O(√
n
/ϵ ⋅ log
2
(
n
/ϵ)) time and has a query complexity of O(√
n
/ϵ ⋅ log (
n
/ϵ)).