bluuebunny/crossref_metadata_2025 huggingface dataset:
Methods for estimating the critical shear stress of individual fractions in mixed‐size sediment
Authors: Wilcock Peter R.
Published: February 2008

Two methods are commonly used to estimate the critical shear stress of individual fractions in mixed‐size sediment, one using the largest grain displaced, the other using the shear stress that produces a small value of transport rate for each fraction. The initial‐motion results produced by the two methods are typically different: largest‐grain critical shear stresses vary with roughly the square root of grain size, and reference transport critical shear stresses show little variation with grain size. Comparison of the two methods is seldom possible because both methods can rarely be applied to the same data. The one case known for which both methods can be used suggests that the typical differences in initial‐motion results reflect more methodological influence than real differences in the initial motion of different sediments. Although the two classes of methods may not be directly compared, a general definition of initial‐motion in mixed‐size sediment is presented that allows the characteristic differences between the results to be explained in terms of sampling and scaling considerations inherent in the mixed‐size initial‐motion problem. The initial‐motion criterion defined also provides a rational basis for collecting comparable and reproducible data using the two classes of method.
A new approximate technique for the hodograph method in groundwater flow and its application to coastal aquifers
Authors: Detournay C. , Strack O. D. L.
Published: February 2008

The solution to a steady, two‐dimensional problem of flow in a coastal aquifer is derived to illustrate the application of a new approximate analytical technique. The problem involves the determination of a phreatic surface, an interface separating flowing freshwater from salt water at rest, a seepage face, and an outflow face where freshwater leaves the homogeneously permeable porous medium to flow into the sea. The solution which expresses the relation between the complex potential Ω and the complex variable z, defined in the flow domain, is obtained by application of conformal mapping techniques using the hodograph method. Three auxilliary planes are introduced: the ζ plane, a reference half plane, the plane of the specific discharge function w, which is the complex conjugate of the hodograph, and the plane of the reference function R, a function of the first derivative of z and w with respect to ζ. The boundary of the flow domain, which is not known beforehand, corresponds to a polygon composed of circular arcs and straight line segments in the w plane and to a polygon of straight lines through the origin in the R plane. The function that maps the ζ plane onto the R plane is expressed analytically. In the proposed technique, the analytic function ζ=ζ(w) is evaluated using a new boundary element approximation. It is shown that the solution to the flow problem may be derived from those two relations in terms of w.
An econometric study of industrial water demands in British Columbia, Canada
Authors: Renzetti Steven
Published: February 2008

Despite the importance of water use by the industrial sector, little economic research has been conducted to study the nature of industrial water demands. This paper uses a relatively simple model of input demands to test whether industrial water use is sensitive to changes to input prices or the level of production. Demands for four aspects of industrial water use (intake, treatment prior to use, recirculation, and treatment prior to discharge) are estimated as a system of simultaneous equations. The data set is a 1981 cross section of firm level observations on water use and expenditure. Empirical results are reported for four manufacturing subgroups: petrochemicals, heavy industry, forest industry, and light industry. Intake price elasticities range from −0.12 to −0.54 and intake elasticities with respect to the level of output range from 0.76 to 1.90. The cross price elasticity between intake and recirculation is positive for all subgroups (indicating substitutability) and ranges from 0.14 to 0.26.
Is optimization optimistically biased?
Authors: Hobbs Benjamin F. , Hepenstal Ann
Published: February 2008

Does optimization systematically lead to solutions that appear better than they actually turn out to be when implemented? The answer can be yes if there are errors in estimating objective function coefficients. Even if such errors are unbiased, the calculated value of the objective function for the optimal solution will, in an expected value sense, overstate that solution's true performance. This presupposes that errors in the constraint set are relatively unimportant. The existence of such a bias is shown by proof; Monte Carlo simulations of two realistic water resources optimization problems show its significance for water planners. The most important implication is that the estimated net benefits of model solutions may be exaggerated compared to existing water systems, whose performance is generally known with more accuracy.
Flow to a well near the boundary between a layered and an unlayered aquifer system
Authors: Hunt Bruce , Curtis T. Gray
Published: February 2008

A closed‐form solution is obtained for flow to a well near the boundary between a layered and an unlayered aquifer system. The well is assumed to abstract a different flow rate from each of the N aquifers, and the top and bottom boundaries are assumed to be impermeable. The solution is obtained by using a single potential function to calculate boundary conditions along the common boundary between the layered and unlayered regions. Then the solution for the layered region is obtained by solving a generalized eigenvalue problem. Numerical examples are worked in order to illustrate the use of the solution for several particular cases.
Size‐selective entrainment of bed load in gravel bed streams
Authors: Ashworth Philip J. , Ferguson Robert I.
Published: February 2008

Entrainment of mixed size gravel bed material was studied in nine reaches of three high‐power streams in Scotland and Norway. Paired measurements of at‐a‐point shear stress (estimated from velocity profiles) and bed load transport (by hand‐held sampler) were made. They extended to very high values (400 N m−2, 3.5 kg m−1 s−1). Analyses of maximum bed load diameter, mean bed load diameter, transport rates of individual size fractions, and tracer pebble movements all show some dependence of threshold shear stress for entrainment on absolute particle size, despite strong relative size effects. Precise equal mobility of all sizes was approached in the data set with the highest shear stresses and transport rates. Size‐selective transport in the streams studied is also indicated by clear downstream and downbar reductions in surface sediment size over distances too short for abrasion to be significant.
Dune migration in a steep, coarse‐bedded stream
Authors: Dinehart Randy L.
Published: February 2008

During 1986 and 1987, migrating bed forms composed of coarse sand and fine gravel (d50=1.8 to 9.1 mm) were documented in the North Fork Toutle River at Kid Valley, Washington, at flow velocities ranging from 1.6 to 3.4 m s−1 and depths of 0.8 to 2.2 m. The bed forms (predominantly lower regime dunes) were studied with a sonic depth sounder transducer suspended in the river at a stationary point. Twelve temporal depth‐sounding records were collected during storm runoff and nearly steady, average streamflow, with record durations ranging from 37 to 261 min. Waveform height was defined by dune front heights, which ranged from 12 to 70 cm. A weak correlation between flow depth and the standard deviation of bed elevation was noted. Dune front counts and spectral analyses of the temporal records showed that dune crests passed the observation point every 2 to 5 min. Dunes were often superposed on larger bed forms with wave periods between 10 and 30 min. Gradual changes in waveform height and periodicity occurred over several hours during storm runoff. The processes of dune growth and decay were both time‐dependent and affected by changes in streamflow. Rates of migration for typical dunes were estimated to be 3 cm s−1, and dune wavelengths were estimated to be 6 to 7 m.
Hypolimnetic mixing in a weakly stratified lake
Authors: Aldama Alvaro A. , Harleman Donald R. F. , Adams E. Eric
Published: February 2008

The evolution of the thermal structure of a weakly stratified lake, located in Venezuela, is studied by applying a hydrothermal model as a tool to analyze the observed data. Particular attention is given to the quantification of the mixing energies involved in the redistribution of heat content in the epilimnion and in the hypolimnion. Hence an analysis of the epilimnetic and hypolimnetic mixing dynamics is presented. As a result, expressions for epilimnetic (wind stirring and penetrative convection) and hypolimnetic mixing energies are obtained and it is concluded that for the lake in study, hypolimnetic mixing controls the local thermal structure and the overall heat transfer process.
A parametric model for steeply sloping forested watersheds
Authors: Ormsbee Lindell E. , Khan Abdul Q.
Published: February 2008

With the objective of simulating storm hydrographs in steeply sloping forested watersheds in humid regions, the kinematic storage model of S1oan and Moore (1984) was embedded into an existing watershed model (HEC 1) and applied to a set of selected watersheds in West Virginia and eastern Kentucky. Because of the marginal performance of the model, a more comprehensive model structure was developed which explicitly considers both macropore and micropore flow mechanisms. Application of the new model to the selected watersheds produced much better correlations between the observed and predicted watershed responses such as the runoff volume, the peak discharge, and the time to peak. Calibrated model parameters were found to exhibit a strong seasonal dependency. As a result, it was concluded that the underlying response mechanisms are highly influenced by seasonal changes in both the surface and subsurface characteristics of the watersheds.
An analytic technique for stochastic analysis in environmental models
Authors: Tumeo Mark A. , Orlob Gerald T.
Published: February 2008

This paper describes the development and application of a new mathematical technique to include stochasticity in environmental models. The technique, named the probability density function/moment (PDF/M) technique by the authors, is based on a two‐tiered process. First, the basic governing equations are expanded to include stochastic terms. Stochastic terms are separated from nonfluctuating terms, and the resulting set of equations is solved simultaneously. Solutions are used to calculate the moments of the output variables. Second, the moments are used in conjunction with the Fokker‐Planck equation to produce an analytical solution for the probability density functions of the dependent variables. Because the approach produces analytical solutions, it offers greater flexibility than a Monte Carlo approach in treating complex environmental situations. Unlike the stochastic differential equation approach, it is not necessary to assume Gaussian distributions in the solution technique, complex random functions of time and space may be included, and solutions are possible for higher‐dimensioned problems and cases with stochastic variations in stream velocity. The PDF/M technique represents a new and potentially powerful tool for extending the capabilities of computer models in management and decision analysis by providing analytical solutions for the probability density functions and associated moments of important environmental variables.
A quarter century of Water Resources Research
Authors: Davis George H.
Published: February 2008

On this twenty‐fifth anniversary of Water Resources Research (WRR), I can well recall the circumstances of its founding. Prior to the 1950s, the chief professional homes for water scientists had been societies such as the American Society of Civil Engineers, the American Water Works Association, and the American Chemical Society, where water was secondary to the main theme of specific disciplines: engineering, public health, and chemistry. The American Geophysical Union (AGU), on the other hand, was a multidisciplinary grouping, where water scientists found a congenial environment in the AGU Hydrology Division. The division not only flourished but soon became the largest unit in AGU.
Farm program impacts on an exhaustible groundwater supply: An analysis of the Texas Southern High Plains
Authors: Lee John G. , Lacewell Ronald D.
Published: February 2008

Stochastically simulated crop yields were combined with random correlated crop prices to provide input into a recursive quadratic programming model to evaluate optimal irrigated crop selection and associated rates of groundwater withdrawals. Three farm program scenarios were evaluated in two areas of the Southern High Plains. Participation in the current farm program increased net returns and groundwater extraction rates above nonparticipation. Discounted net returns were projected to decline across all farm program scenarios. Risk averse preferences in crop mix decisions decreased cumulative groundwater extraction rates through reduced irrigated acres but had higher per acre application rates compared with the risk neutral case.
Determining the mean depth of overland flow in field studies of flow hydraulics
Authors: Abrahams Athol D. , Parsons Anthony J.
Published: February 2008

In field studies of interrill overland flow conducted on runoff plots, the mean depth of flow is usually obtained by averaging measurements of flow depth at regularly spaced points across the plot, including points where there is no flow. Although this procedure may be appropriate in studies aimed at runoff prediction, it is not in studies concerned with flow hydraulics. In the latter studies, more realistic results can be obtained by excluding those points where the depth is zero and reducing the width of flow in proportion to the number of points excluded. Failure to do this results in the underestimation of the actual mean flow depth, Reynolds number, and friction factor. Where discharges are small or microtopography is large, this underestimation is likely to be significant.
Simulating costs of flooding under alternative policies for the Sacramento‐San Joaquin River Delta
Authors: Logan Samuel H.
Published: February 2008

A computer model is used to simulate floods and associated annual and present value costs for California's Sacramento‐San Joaquin Delta. Empirical probability distributions of stability failure and overtopping floods for 46 islands and tracts, conditioned on water levels, are used to simulate floods. When an island floods, damage and reclamation costs are determined. The cost of levee maintenance in nonflood years is also a random variable. Multiple simulations over 50‐year periods provide means and variances of annual costs of policies of reclaiming all flooded islands or reclaiming only some of them. When discounted, the resulting present value of a future stream of these costs may be compared to costs of alternative flood prevention programs (e.g., new levees). Results show that the present value of costs over 50 years for reclaiming all islands differs little from the comparable cost of reclaiming only 13 islands and leaving other islands flooded. Under both policies the present value of costs is less than the first cost of levee projects presented by the Corps of Engineers in the early 1980s.
Optimization of the pumping schedule in aquifer remediation under uncertainty
Authors: Andricevic Roko , Kitanidis Peter K.
Published: February 2008

A common method of aquifer decontamination is through “pump and treat” systems. Mathematical models of flow and transport can be incorporated into an optimization scheme to determine the most cost‐effective pumping pattern and schedule, provided that the parameters of the system are somehow known. In practice, however, there is seldom enough information to specify with certainty all the parameters of the system. Parameters are obtained from measurements through inverse modeling and are subject to error. This work presents an optimization methodology which accounts for and reduces parameter uncertainty. It is shown that in an average sense the cost consists of two parts: one which depends only on the best estimates and another which increases with the error in parameter estimation. A policy which minimizes the sum of the two parts is developed. The proposed methodology elucidates the dual control aspect of stochastic control, i.e., the control policy (pumping schedule) optimizes the objective function by, among other things, improving the accuracy of estimation of system parameters (i.e., dispersivity, transmissivity). For purposes of illustration, the proposed method is applied to a simple case. Comparison with an optimization method which neglects uncertainty in parameter estimation shows the superiority of the proposed algorithm.
Coupled saturated‐unsaturated quasilinearized steady state flows from buried and surface cavities
Authors: Pullan A. J.
Published: February 2008

The coupled saturated‐unsaturated flow that results from water‐filled cavities in soils is studied, under the assumption of quasilinearization for the unsaturated flow, using a combined boundary element‐finite element method. Buried two‐dimensional circular cylindrical cavities and two‐dimensional semicircular cavities are examined in detail. The effect of the size of the cavity and the soil type on the flux from the cavity and the size of the saturated zone and effectively wetted region is illustrated. Comparisons with previous analytical and numerical results, in which the depth of water in the cavity was neglected, are also made. These comparisons indicate the severe errors that are introduced into the calculation of the flux and the flow field when the depth of water is neglected. In particular, it is shown that the percentage error in the flux from a buried circular cylinder with water depth neglected increases from 20% to 220% as the dimensionless cavity size s increases from 0.1 to 1, and that the saturated zone extends to a depth of approximately 7.9 times the cavity radius for s = 1.
Curious behavior of a groundwater flow model
Authors: Fink James P.
Published: February 2008

The linearized Boussinesq equation and equations derived from it are sometimes regarded as corrections to the basic diffusion equation. By looking at a specific model we show that this interpretation should be handled with caution and discuss the underlying mathematical principles involved.
Quantum trajectory analysis of single-photon control from a single-molecule source
Authors: Xue Yongqiang , Kennerly William W.
Published: February 2008

We investigate theory of single-photon control from a two-level single-molecule source irradiated by laser pulses of various shapes and pulse durations in terms of quantum trajectories which link stochastic dynamics of the radiating source with quantum measurement theory. Using Monte Carlo wave function simulation, we analyze the detailed dissipative dynamics of the single-molecule source and the photon statistics as revealed by repeated Gedanken photon measurement on the single radiating source. We show that much of the photon statistics from the two-level single-molecule single-photon sources, including few-photon emission probability, waiting time distribution, and two-time correlation function of the fluorescent light, can be understood qualitatively from the simple picture of Rabi nutation and π pulse in terms of pulse areas.
High coercive L10 FePt–C (001) nanocomopsite films with small grain size for perpendicular recording media
Authors: Chen J. S. , Hu J. F. , Lim B. C. , Lim Y. K. , Liu B. , Chow G. M. , Ju G.
Published: February 2008

FePt–C films with various C concentrations were deposited on MgO∕CrRu/glass substrate by cosputtering FePt and C at 350°C. The evolution of magnetic properties and microstructure of FePt–C films with the C concentration were investigated. All FePt films showed (001) preferred orientation regardless of C concentrations. With C doping, a two-layer structure of FePt–C films was formed. The FePt–C underlying layer epitaxially grown on MgO intermediate layer were L10 FePt grains, while the FePt overlayer consisted of fcc FePt phase and L10 FePt phase. The out-of-plane coercivity measured at room temperature increased from 10.2to19kOe when C concentrations increased from 0% to 15%. Further increasing the C contents to 20% and 25% caused the decrease of coercivity to 17.2 and 14.8kOe, respectively.
Electromagnetic properties of ferromagnetic nanowire arrays
Authors: Boucher Vincent , Ménard David
Published: February 2008

A general model for the effective permeability and permittivity tensors of ferromagnetic nanowire arrays, based on a Maxwell-Garnett homogenization procedure, is proposed and incorporates the effects of the geometric parameters of the array, the shape of the wires, and their intrinsic dielectric and magnetic properties. Effective external tensors, which include the dynamic dipolar dielectric and magnetic interwire interactions, are then derived to provide a link between the effective susceptibilities of the array and those measured in microwave cavity experiments. The emphasis is put on the prediction that ferromagnetic nanowire arrays may exhibit simultaneously gyromagnetic and magnetodielectric responses, which are both tunable by an external static magnetic field.
Localized and free exciton spin relaxation dynamics in GaInNAs∕GaAs quantum well
Authors: Lu S. L. , Bian L. F. , Uesugi M. , Nosho H. , Tackeuchi A. , Niu Z. C.
Published: February 2008

We have investigated the exciton spin relaxation in a GaInNAs∕GaAs quantum well. The recombination from free and localized excitons is resolved on the basis of an analysis of the photoluminescence characteristics. The free exciton spin relaxation time is measured to be 192ps at 10K, while the localized exciton spin relaxation time is one order of magnitude longer than that of the free exciton. The dependence of the free exciton spin relaxation time on the temperature above 50K suggests that both the D’yakonov–Perel’ and the Elliot–Yafet effects dominate the spin relaxation process. The temperature independence below 50K is considered to be due to the spin exchange interaction. The ultralong spin relaxation time of the localized excitons is explained to be due to the influence of nonradiative deep centers.
The Grapefruit Race: Demonstrating the Influence of Competition on Gender Differences in Intimacy
Authors: Hebl Mikki R. , King Eden B. , McGuire Julie , Turchin Melissa
Published: February 2008

We present an interactive demonstration of factors that mitigate gender differences. Male and female volunteers pass a grapefruit from one classmate to the next using only their chins. The speed of task completion depends on its framing; when the volunteers believe the task is an exercise, women tend to be faster than men, whereas the opposite effect emerges when the task is framed as a competition. Student observers rated the demonstration positively and indicated positive learning outcomes regarding the context-dependent nature of gender differences in comfort with same-sex intimacy. This article offers an effective demonstration of gender differences in intimate behavior and illustrates a situation in which gender differences can be malleable.
Involvement of insulin‐like growth factor‐insulin receptor signal pathway in the transgenic mouse model of medulloblastoma
Authors: Sun Qiang , Wei Xiaoluan , Feng Jie , Zhang Rong , Shen Qian , Dong Juan , Jin Yujuan , Dong Suzhen , Li Houda , Hu Yinghe
Published: February 2008

A transgenic mouse model expressing Simian virus 40 T‐antigen (SV40Tag) under the control of a tetracycline system was generated. In this model, a cerebellar tumor was developed after doxycycline hydrochloride treatment. Real time‐polymerase chain reaction and immunohistochemistry results indicated that the SV40Tag gene was expressed in the tumor. Pathological analysis showed that the tumor belonged to medulloblastoma. Further molecular characterization of the tumor demonstrated that the insulin‐like growth factor (IGF) signaling pathway was activated. We also found that the SV40Tag could bind and translocate insulin receptor substrate 1 into the nucleus in primary cultured tumor cells. The interaction between the IGF pathway and SV40Tag may contribute to the process of malignant transformation in medulloblastoma. This transgenic animal model provides an important tool for studies on the signal pathways involved in the preneoplastic process in medulloblastoma and could help to identify therapeutic targets for brain tumors. (Cancer Sci 2008; 99: 234–240)
Tumor vaccine therapy against recrudescent tumor using dendritic cells simultaneously transfected with tumor RNA and granulocyte macrophage colony‐stimulating factor RNA
Authors: Naka Teiji , Iwahashi Makoto , Nakamura Masaki , Ojima Toshiyasu , Nakamori Mikihito , Ueda Kentaro , Katsuda Masahiro , Miyazawa Motoki , Ishida Koichiro , Yamaue Hiroki
Published: February 2008

Recently, dendritic cells (DC) transfected with tumor RNA have been used as a cancer vaccine. The efficacy of a cancer vaccine using DC transfected tumor RNA was examined. Of particular interest was whether a vaccine using DC transfected with recrudescent tumor RNA is effective for the treatment of a regrowing tumor after prior immunotherapy. In addition, the usefulness of co‐transfection of granulocyte macrophage colony‐stimulating factor (GM‐CSF) mRNA to augment the DC vaccine was examined. CT26 tumor‐bearing mice were immunized by s.c. injection with DC transfected with CT26 mRNA (DC‐CT26). The cytotoxic activity against CT26 in mice immunized with DC‐CT26 was significantly higher than that in the control group (P < 0.001) and was augmented by GM‐CSF mRNA co‐transfection (P < 0.05), resulting in remarkable therapeutic efficacy in CT26 s.c. tumor models. Cytotoxic T lymphocytes induced by the vaccination using DC transfected with mRNA from the recrudescent tumor showed a potent cytotoxicity against the recrudescent CT26 tumor cells, which was significantly higher than the cytotoxicity induced by the vaccination using DC‐CT26 (P < 0.05). In addition, in a recrudescent tumor model, this vaccination suppressed the regrowing s.c. tumors, and was augmented by GM‐CSF mRNA co‐transfection (P < 0.05). These results suggested that vaccination therapy using DC simultaneously transfected with whole tumor RNA and GM‐CSF mRNA could generate therapeutic immune responses even against recrudescent tumor after prior vaccination. (Cancer Sci 2008; 99: 407–413)
Peptide nucleic acid–locked nucleic acid polymerase chain reaction clamp‐based detection test for gefitinib‐refractory T790M epidermal growth factor receptor mutation
Authors: Miyazawa Hitoshi , Tanaka Tomoaki , Nagai Yoshiaki , Matsuoka Masaru , Huqun  , Sutani Akihisa , Udagawa Kiyoshi , Zhang Jialing , Hirama Takashi , Murayama Yoshitake , Koyama Nobuyuki , Ikebuchi Kenji , Nagata Makoto , Kanazawa Minoru , Nukiwa Toshihiro , Takenoshita Seiichi , Kobayashi Kunihiko , Hagiwara Koichi
Published: February 2008

Mutations in the epidermal growth factor receptor (EGFR) are observed in a fraction of non‐small‐cell lung cancers (NSCLS). EGFR mutation‐positive NSCLS responds to gefitinib. Secondary T790M mutation confers gefitinib resistance to NSCLS. A detection test for the T790M mutation was designed based on the peptide nucleic acid–locked nucleic acid polymerase chain reaction clamp method. The specificity and sensitivity of the test were both greater than 0.99. The test revealed that only a small population of the PC‐13 cells carried the T790M mutation. The test also revealed that the T790M mutation was found in none of 151 NSCLC specimens obtained before gefitinib treatment, whereas it was found in four of four specimens obtained from NSCLS that had become refractory to gefitinib. In one patient in whom the L858R‐positive EGFR allele was amplified to multiple copies, an L858R‐T790M double‐mutant allele emerged during the gefitinib therapy. This allele was expressed highly. The T790M mutation detection test based on the peptide nucleic acid–locked nucleic acid polymerase chain reaction clamp method is sensitive and specific, and is applicable to clinical practice. It detects T790M‐positive cells in the course of gefitinib treatment, and thus will help to devise therapies effective for T790M‐positive NSCLS. (Cancer Sci 2008; 99: 595–600)
Induction of mitochondria‐involved apoptosis in estrogen receptor‐negative cells by a novel tamoxifen derivative, ridaifen‐B
Authors: Nagahara Yukitoshi , Shiina Isamu , Nakata Kenya , Sasaki Akane , Miyamoto Tomomi , Ikekita Masahiko
Published: February 2008

Tamoxifen is an antagonist of estrogen receptor, which is used widely as an estrogen receptor‐positive breast cancer drug that blocks growth signals and provokes apoptosis. However, recent studies have revealed that tamoxifen induces apoptosis even in estrogen receptor‐negative cells. In the present study, we synthesized several tamoxifen derivatives to augment the apoptosis‐inducing effect of tamoxifen and evaluated the apoptosis‐inducing pathway. The estrogen receptor‐positive human leukemia cell line HL‐60 and estrogen receptor‐negative human leukemia cell line Jurkat were treated with tamoxifen and synthesized tamoxifen derivatives, and thereafter subjected to cell viability‐detection assays. Tamoxifen derivatives, as well as the lead compound tamoxifen, decreased the cell viability despite the expression of estrogen receptor. Among all of the synthesized tamoxifen derivatives, ridaifen‐B had more potent cancer cell‐damaging activity than tamoxifen. Ridaifen‐B fragmented Jurkat cell DNA and activated caspases, suggesting that the ridaifen‐B‐induced apoptosis pathway is estrogen receptor independent. Moreover, mitochondrial involvement during ridaifen‐B‐induced apoptosis was estimated. Ridaifen‐B significantly reduced mitochondrial membrane potential, and overexpression of Bcl‐2 inhibited ridaifen‐B‐induced apoptosis. These results suggest that the induction of apoptosis by ridaifen‐B, a novel tamoxifen derivative, is dependent on mitochondrial perturbation without estrogen receptor involvement. (Cancer Sci 2008; 99: 608–614)
Anti‐tumor activity and tumor vessel normalization by the vascular endothelial growth factor receptor tyrosine kinase inhibitor KRN951 in a rat peritoneal disseminated tumor model
Authors: Taguchi Eri , Nakamura Kazuhide , Miura Toru , Shibuya Masabumi , Isoe Toshiyuki
Published: February 2008

We assessed the antitumor efficacy of KRN951, a novel tyrosine kinase inhibitor of vascular endothelial growth factor receptors, using a rat colon cancer RCN‐9 syngeneic model in which the tumor cells are transplanted into the peritoneal cavity of F344 rats. KRN951 treatments that commenced 4 days after tumor transplantation (day 4) significantly inhibited tumor‐induced angiogenesis, the formation of tumor nodules in the mesenteric windows, and the accumulation of malignant ascites. Moreover, KRN951 treatments initiated on day 14, by which time angiogenesis and malignant ascites have already been well established, resulted in the regression of newly formed tumor vasculatures with aberrant structures and also in the apparent loss of malignant ascites by the end of the study period. Quantitative analysis of the vessel architecture on mesenteric windows revealed that KRN951 not only regressed, but also normalized the tumor‐induced neovasculature. Continuous daily treatments with KRN951 significantly prolonged the survival of rats bearing both early stage and more advanced‐stage tumors, compared with the vehicle‐treated animals. The results of our current study thus show that KRN951 inhibits colon carcinoma progression in the peritoneal cavity by blocking tumor angiogenesis, ascites formation, and tumor spread, thereby prolonging survival. Moreover, these studies clearly demonstrate the therapeutic effects of KRN951 against established tumors in the peritoneal cavity, including the regression and normalization of the tumor neovasculature. Our findings therefore suggest that KRN951 has significant potential as a future therapeutic agent in the treatment of peritoneal cancers with ascites. (Cancer Sci 2008; 99: 623–630)
Rice JASMONATE RESISTANT 1 is involved in phytochrome and jasmonate signalling
Authors: RIEMANN MAREN , RIEMANN MICHAEL , TAKANO MAKOTO
Published: February 2008

Jasmonic acid (JA) is an important negative regulator of light‐regulated coleoptile elongation in rice. We isolated rice JASMONATE RESISTANT 1 (osjar1) mutants from the Tos17 mutant panel by BLAST search. In far‐red and blue lights, osjar1 coleoptiles were longer if compared with the wild type (WT), indicating that OsJar1 participates in the suppression of coleoptile elongation in these light conditions, while the mutant did not show a clear phenotype in red light. The analysis of OsJar1 expression in phytochrome (phy) mutants revealed that phytochrome A (phyA) and phytochrome B (phyB) act redundantly to induce this gene by red light, presumably. Unexpectedly, blue light‐induced expression of OsJar1 gene was impaired in phyA‐deficient mutants, indicating the involvement of phyA in the blue light signalling. In WT seedlings, OsJar1 transcripts were up‐regulated transiently in response to treatment with exogenous methyl‐jasmonic acid (MeJA). The dose–response curve of the MeJA treatment showed a characteristic pattern: concentrations as low as 4.5 nm could induce OsJar1 transcription, while the gene was superinduced at a concentration of 450 µm MeJA. In summary, this paper demonstrated that OsJar1 modulates light and JA signalling in the photomorphogenesis of rice.
MICROSTRUCTURAL EFFECT ON LOW CYCLE FATIGUE BEHAVIOUR IN Ti‐ALLOYS UNDER BIAXIAL LOADING
Authors: Hoshide T. , Kakiuchi E. , Hirota T.
Published: February 2008

Abstract— Low cycle fatigue tests under axial, torsional and combined axial‐torsional loading were conducted using thin‐wall tubular specimens of Ti‐6A1–4V titanium alloys. Two kinds of alloys with different microstructures, the (α+β) and β alloys, were investigated in fatigue tests at room temperature. When the failure life was correlated with the equivalent plastic strain, the life in axial loading shifted toward the lower life region compared with those in other loading modes in both alloys. Dominant surface cracks propagated in mode I under axial and combined loading in the two alloys. Although growth by the mode II type was predominant under torsional loading, the growth direction of the main crack coincided with the specimen axis in the (α+β) alloy, but the circumferential direction in the β alloy. The cracking morphology depended on the microstructure, especially under the torsional mode of loading, and was simulated successfully by using the proposed model for crack initiation.
Taking ‘Big Government Conservatism’ Seriously? The Bush Presidency Reconsidered
Authors: BÉLAND DANIEL , WADDAN ALEX
Published: February 2008

This article reflects on the ongoing debate about the ideological direction of the Bush presidency and what it means for the future of US conservatism in domestic policy. The paper considers the dual nature of US conservatism and then goes on to explore the ‘conservative promise’ of the 2000 presidential election and the debate over what critiques of the Bush administration have come to call ‘big government conservatism’. Finally, the article studies two examples of how this alleged ‘big government conservatism’ has been manifested. First, the article contemplates the administration's fiscal policy. Second it looks at the 2003 reform of the Medicare system. We argue that, although these two cases provide some ground to the idea of ‘big government conservatism’, in the end this phenomenon does not add up to a coherent policy vision. Overall, beyond tax cuts, the Bush administration has failed to implement a bold conservative agenda.
Nonsurgical treatment of stress urinary incontinence (SUI): grading of evidence in systematic reviews
Authors: Latthe PM , Foon R , Khan K
Published: February 2008

Background  The guidance on SUI has not been rigorously assessed using GRADE system.

Objective  To determine if the quality and results of existing systematic reviews on conservative treatment of stress urinary incontinence (SUI) can underpin evidence‐based recommendations for practice.

Study design  Review of systematic reviews.

Data sources  Electronic search in PubMed, Medline (OVID 1966‐version), CINAHL, Biomed, Psychinfo, the Cochrane library, National Library for Health, the National Research Register and hand search of reference lists.

Methods  Two reviewers independently selected systematic review articles in which a publicly available database was searched for randomised trials on conservative treatment of SUI and assessed them for quality of methods and results (OR and 95% CIs). The extracted information was used to classify strength of evidence as per the Grading of Recommendations, Assessment, Development, and Evaluation (GRADE) system.

Results  There were 13 reviews of variable quality. Quality assessment of studies included in the reviews and their findings were adequately tabulated in all but four reviews. Meta‐analysis of data was carried out in six reviews. Pelvic floor muscle training (PFMT) and other physical treatments, estrogens and duloxetine were better than no treatment in SUI. Based on the assessment as per GRADE system, only 2/13 (15.4%) reviews were deemed to be of high quality, 8/13 (61.5%) of moderate quality and 3/13 (23.1%) of low quality. The case for recommendation of PFMT and duloxetine was strong.

Conclusion  Systematic reviews of conservative treatments of SUI are not always suitable to generate robust recommendations for practice as they are weak in methodological quality or lack power to produce reliable results.
ISOLATION OF A NON‐PHAGE‐LIKE LYTIC VIRUS INFECTING AUREOCOCCUS ANOPHAGEFFERENS1
Authors: Rowe Janet M. , Dunlap John R. , Gobler Christopher J. , Anderson O. Roger , Gastrich Mary D. , Wilhelm Steven W.
Published: February 2008

We have been working to characterize viruses that infect the HAB‐forming pelagophyte Aureococcus anophagefferens Hargraves et Sieburth. Field samples were collected during brown‐tide events in 2002 and tested for the presence of lytic agents. Here, we describe a recently isolated, lytic virus‐like particle (VLP) that is morphologically similar to particles observed in thin sections of infected A. anophagefferens cells from natural samples. TEM and SEM have revealed VLPs consistent with the morphological characteristics of previously described Phycodnaviridae. Large icosahedral particles (∼140 nm) of similar shape and morphology dominate cell lysates and are accompanied by smaller phage‐like particles and heterotrophic prokaryotes that appear to be incurable from our cultures. To determine which of these particles interacts with the Aureococcus cells, we preserved cultures during the early stage of infection so that SEM could be used to visualize those particles that attach to the surface of naïve cultures. SEM revealed that 63% of the large icosahedral‐shaped particles attached to A. anophagefferens cells after only 30 min of exposure, while no significant frequency of attachment to the alga was observed for the phage‐like particles. The results of these observations are in contrast to previous studies, where phage‐like particles were reported to infect cells. When considered in conjunction with field observations, the results suggest that this newly isolated virus represents the dominant virus‐morphotype associated with bloom collapse and termination.
Candida albicans Adherence to Surface‐Modified Denture Resin Surfaces
Authors: Park Sang E. , Blissett Ryan , Susarla Srinivas M. , Weber Hans‐Peter
Published: February 2008

Purpose: The purpose of this study was to investigate two innovative methods in reducing adhesion of Candida albicans to denture base resins through modification of the surface characteristics of denture resin by incorporation of surface charge and application of a self‐bonding polymer on denture resins.

Materials and Methods: Three groups were tested [Group 1: control, pure poly(methyl methacrylate) (PMMA); Group 2: modified PMMA (mPMMA) with 16% methacrylic acid; Group 3: pure PMMA coated with self‐bonding polymer (SBP)]. Twenty resin specimens for each group were polymerized, and four experimental subgroups for each surface type were devised, consisting of 2, 4, 6, and 12 days of incubation in C. albicans suspension. The surface area of adherent C. albicans stained with Gram's crystal violet was examined under a light microscope at 400× magnification. Four areas were photographed on each block, one on each quadrant. The images were analyzed using Scion Image 1.63 software to calculate the percent surface area containing adherent C. albicans. Kruskal–Wallis test and Tukey's honest significant difference (HSD) procedure were used to compare the groups.

Results: At day 2, the modified resin had statistically significantly lower levels of Candida than both the control group and the SBP group (p< 0.036). Both the mPMMA group and SBP group had statistically significantly lower levels of Candida accumulation at days 4, 6, and 12, compared to the control.

Conclusions: The amount of C. albicans adhering to the resin surfaces reduced significantly with modification of surface charge and application of self‐bonding polymer. Modification of surface characteristics of polymeric biomaterials is an effective method in reducing adhesion of C. albicans to PMMA surfaces.
The Effect of Aging by Thermal Cycling and Mechanical Brushing on Resilient Denture Liner Hardness and Roughness
Authors: Hermann Caio , Mesquita Marcelo Ferraz , Consani Rafael Leonardo Xediek , Henriques Guilherme Elias Pesanha
Published: February 2008

Purpose: The purpose of this study was to investigate the effects of aging on resilient denture liners. The aging effects were produced by using thermal cycling and mechanical brushing and were quantified as changes to surface hardness and roughness of resilient denture liners.

Material and Methods: A plasticized acrylic resin (Dentuflex) and two silicone‐based (Molloplast‐B, Sofreliner MS) resilient denture liners were examined. Pre‐ and post‐test roughness and hardness measurements were recorded using a Surfcorder SE 1700 and Shore A durometer Teclock GS‐709, respectively. Sixty specimens were manufactured; half were subjected to 3000 cycles in the thermal cycler (5 and 55°C). The remaining specimens received 30,000 strokes applied by a mechanical brushing machine followed by 3000 thermal cycles. Representative specimens from each group were observed under scanning electron microscope (SEM). Data were examined by multiple ANOVA, split‐plot analysis, and Tukey test (α= 0.05).

Results: Shore A hardness values for Dentuflex, Molloplast‐B, and Sofreliner MS soft liners were different from each other (p < 0.05) before (79 ± 2.9; 40 ± 1.4; 33 ± 0.7) and after (80 ± 3.1; 40 ± 1; 34 ± 0.9) thermocycling. The surface roughness (in μm) of the same soft liner materials was significantly different (p < 0.05) at the start (2.2 ± 0.4; 1.6 ± 0.6; 0.2 ± 0.1) but it was not different (p > 0.05) after tooth brushing (1.7 ± 0.3; 1.7 ± 0.4; 1.9 ± 0.8) or thermocycling (1.6 ± 0.5; 1.6 ± 0.6; 1.5 ± 0.5)

Conclusion: Thermal cycling promoted increased hardness for Sofreliner MS and Dentuflex. Mechanical brushing promoted wear abrasion in Sofreliner MS and Dentuflex materials. Molloplast‐B experienced no deleterious effects from either of the tests.
Cephalic arch stenosis in patients with fistula access for hemodialysis: Relationship to diabetes and thrombosis
Authors: HAMMES Mary , FUNAKI Brian , COE Fredric L.
Published: February 2008

Numerous studies have identified the fistula as the best access for hemodialysis with fewest complications. The radiocephalic fistula (RCF) is the first access of choice, but often results in poor maturation. Therefore, an increased number of brachiocephalic fistulas (BCF) have been placed. Cephalic arch stenosis (CAS) can occur in patients with fistula access. The current study was done to determine the incidence and associated comorbidities in patients with BCF or RCF who have CAS. A retrospective review of 450 hemodialysis patients in 3 outpatient hemodialysis units between July 1, 2000 and July 1, 2005 (60 months) was preformed. We reviewed demographics, medications, and indications for venograms. Interventional Radiologists reviewed the venograms for evidence of CAS. Radiology reports were screened to determine incidence of thrombosis, treatment with either angioplasty or stent placement and if a complication such as venous rupture occurred. One hundred and twenty‐seven patients had fistula access with at least 1 venogram. Of these, 30 were RCF and 97 were BCF. Cephalic arch stenosis occurred in 77% of patients with BCF and in 20% of patients with RCF. Those with diabetes had a lower rate of occurrence than those without (p<0.01). Cephalic arch stenosis led to a high rate of thrombosis (p<0.01). The probability of having multiple radiology procedures was higher with CAS than without (p<0.01). Cephalic arch stenosis is an important problem in hemodialysis patients who have fistula access, and contributes to thrombosis. Diabetes was found to have a negative association with CAS for undefined reasons. Attempts to understand this relationship are important.
The altitudinal gradient of vascular plant richness in Aurland, western Norway
Authors: Odland Arvid , Birks H. J. B.
Published: February 2008

Differences in vascular plant species richness; along the altitudinal gradient in the Aurland area of western Norway have been investigated. Based on field surveys, as complete lists as possible of all vascular plants have been compiled for each 100 m altitudinal band, from sea level to the highest mountain (1764 m). For each of the 18 altitudinal bands, climatic data have been estimated. A total of 444 vascular plant species were recorded. Highest species richness (263 species) occurred in the 600–700 in band, whereas the uppermost band had only 10 species. There are minor differences in species number between the altitudinal bands < 1000 m. Partial least squares regression shows that species richness for the overall altitudinal gradient is well predicted by mean July and January temperatures and mean annual precipitation. Species turnover is highest in the 100–200 m. 600–700 m. and 1400–1500 m altitudinal bands. In terms of the gradient in summer temperature, the study supports the generally assumed linear relationship between July temperature and the number of vascular plant species between 700 and 1500 m corresponding with a mean July temperature range of 7–11°C. The study shows a decrease of ca 30 vascular plant species with a 1°C decrease in mean July temperature, and that the “climatic vascular plant limit” is here estimated to occur at a mean July temperature of 2.4°C. Above 1500 and below 700 m. species number is lower than expected based on summer iemperature conditions alone. The 700–800 m band represents the highest floristic difference compared to the other bands. Ordination and classification analyses of the floristic compositional data of all the bands highlight the 600–800 and 1500–1600 m altitudinal bands as the major biotic boundaries along the gradient. No major discontinuity in species richness, composition, or turnover was consistently found, however, at the 1100–1200 m band representing the forest‐limit ecotone in Aurland.