bluuebunny/crossref_metadata_2025_split huggingface dataset:
Trace metal analysis of atmospheric particulate matter: A comparison of personal and ambient samplers
Authors: Majestic Brian J. , Schauer James J. , Shafer Martin M. , Fine Philip M. , Singh Manisha , Sioutas Constantinos 
Published: June 2008

This study compared the size-resolved trace metal concentrations from a standard ambient sampler to those of three commercial personal samplers. Trace metals data from each personal sampler were also inter-compared. Co-located “fixed site” samples were collected in two urban sites in the United States using three types of personal samplers (BGI PM2.5 cyclone, URG PM2.5 cyclone, and Sioutas™ personal cascade impactor sampler [PCIS]) and one standard ambient sampler fitted with a PM2.5 cyclone. This experimental design enabled direct evaluation of the relative performance of the personal samplers. Results of mass measurements showed good agreement between the standard equipment and personal samplers;; however, trace metal comparisons (measured by ICP–MS) showed reproducible concentration biases among personal samplers. These biases can be summarized as BGI < URG < PCIS (0.27 ± 0.08, 0.72 ± 0.08, and 1.32 ± 0.34 relative to the ambient sampler). Elements exhibiting larger variation between personal samplers were associated with higher mass fractions in the coarse fraction, suggesting the PM2.5 size-cut a potential cause of this deviation.
Formation of silica grout curtains and containments in mineralized groundwater
Authors: Elektorowicz M. , Hesnawi R. , Ayadat T. , Chifrina R. 
Published: June 2008

An experimental investigation was conducted to evaluate the performance (as reflected by changes in permeability) of grouted soil specimens subjected to waters of various chemistry (mineralized groundwater) under a gradient of approximately 18. The specimens were composed of pure silica sand and clayey silty sand injected with one of two types of sodium silicate grout (sodium silicate + ethyl acetate-formamide, and sodium silicate + calcium chloride). The grouted specimens were tested in an environment that simulated different waters (distilled, freshwater, and saltwater). This work investigated the effects of curing time, environment, grout contents, and groundwater quality on the behaviour of silicate-grouted specimens, and analysed curtain formation mechanism. The test results showed that sodium silicate with ethyl acetate-formamide (SA) exhibited an increase in permeability when subjected to both freshwater and saltwater. Sodium silicate with calcium chloride (SC), however, maintained permeability properties when subjected to both freshwater and saltwater. The SC grouted specimens are less vulnerable to the action of groundwater than specimens grouted with SA. Furthermore, an empirical correlation relating the permeability of ungrouted and grouted specimens under different conditions was suggested. The correlation includes new defined parameters such as curing effect factor (α) and curtain vulnerability factor (κ).
Application of carbon dioxide stripping for struvite crystallization — I: Development of a carbon dioxide stripper model to predict CO2 removal and pH changes
Authors: Fattah K.P. , Zhang Y. , Mavinic D.S. , Koch F.A. 
Published: June 2008

This research investigated the feasibility of stripping CO2 from the digester supernatant to raise the pH, thereby reducing the caustic chemical usage. In this study, a cascade CO2 stripper was first designed and tested, with three different synthetic solutions in a struvite recovery, crystal reactor: (1) tap water saturated with CO2, (2) NaHCO3 solution saturated with CO2, and (3) NaHCO3 + NH4Cl solution saturated with CO2. It was found that the removal efficiency of the CO2 stripper was dependant on several parameters, such as the characteristics of the influent, including total alkalinity, temperature, and initial concentration of dissolved CO2 gas, influent flow rate, effluent recycle rate, aeration rate, and baffle numbers in the stripper. Based on the performance of the stripper on the three synthetic solutions, a CO2 stripping model was developed using these parameters. This model was subsequently tested in a pilot-scale facility, to predict the amount of CO2 removal possible.
Treatment of log yard runoff with a continuous fixed film bioreactor
Authors: Liao Charles , Finnbogason Thomas W. , Duff Sheldon J.B. 
Published: June 2008

Runoff is generated at log yards when precipitation comes into contact with logs, wood debris, and equipment at outdoor wood processing, sorting and storage facilities. Log yard runoff, which can be toxic and have high levels of biochemical oxygen demand (BOD), chemical oxygen demand (COD), and tannin and lignin (T&L), is a potential threat to nearby receiving environments. Runoff samples were collected from two sawmills located in British Columbia (BC). The runoff samples collected had BOD ranging from 16 to 371 mg/L, COD from 230 to 2660 mg/L, and tannin and lignin from 200 to 680 mg/L of tannic acid. Four runoff samples were acutely toxic according to the Microtox® toxicity test. A continuous lab-scale fixed film bioreactor was used to treat the runoff over a range of temperature (5–30 °C) and hydraulic retention times (4–24 h). The reactor was capable of treating runoff with BOD removal ranging from 73.0% to 97.6%, COD removal ranging from 48.0% to 76.9%, and tannin and lignin removal ranging from 27.8% to 60.1%. There appeared to be a transitional change in the makeup of the microbial community in the reactor as the temperature decreased from 15 °C to 10 °C. The reactor was able to remove all acute toxicity at 30 °C, but at lower temperatures treated runoff remained acutely toxic.
Use of goldfish to monitor wastewater and reuse water for xenobiotics
Authors: Kerr Jennifer L. , Guo Zhenyu , Smith Daniel W. , Goss Greg G. , Belosevic Miodrag 
Published: June 2008

Goldfish were exposed to either treated municipal effluent (FE wastewater) or reuse water produced through membrane ultrafiltration (MF reuse water) or membrane ultrafiltration followed by activated carbon filtration (MCF wastewater) for up to 90 days. The xenobiotics present in the wastewater were identified using gas chromatography – mass spectroscopy and the efficacy of their removal by membrane ultrafiltration and activated carbon filtration were determined. At various time points post-exposure to wastewater or reuse water the following biological parameters were assessed: vitellogenin (Vtg) induction, immune gene expression, and mitogen-induced proliferation of blood leukocytes. Membrane ultrafiltration alone did not remove xenobiotics from FE wastewater, while activated carbon filtration efficiently reduced the levels of most xenobiotics. Vitellogenin was induced in fish exposed to both FE wastewater and MF reuse water, but not in fish exposed to MCF reuse water. Messenger ribonucleic acid (mRNA) expression of select immune genes (tumor necrosis factor alpha, colony stimulating factor receptor-1) were up-regulated in FE and MF exposed fish on days 7 and 21 post exposure, while Toll-like receptor 22 mRNA level was similar in fish exposed to wastewater or control water. Prolonged exposure of fish to FE and MF wastewaters caused a significant reduction in the mitogen-induced proliferation of blood leukocytes. Our results suggest that goldfish may be used as biosentinels for xenobiotics present in wastewater and reuse water.
Stockage et stabilité à long terme de boues d’épuration municipales décontaminées et stabilisées par voie chimique ou biologique
Authors: Tremblay Joannie , Blais Jean-François , Drogui Patrick , Mercier Guy 
Published: June 2008

The objective of this research was to evaluate the effects of sewage sludge storage on biological and physico-chemical parameters of sludge treated by different stabilization and decontamination processes. Three sludge storage methods were tested: inside at stable temperature (21 ± 2 °C), outside during summer (May–October), and inside at different temperatures to simulate the winter season. An increase of the sludge pH (approximately 8.0–8.5) and an odour removal process were measured following a 5-month storage period, and this, for all conditions of sludge treatments and storage options. The sanitary conditions of the sludge improved, because the fecal coliforms were completely eliminated, and fecal streptococci and salmonella were significantly reduced. The results also revealed that the pH adjustment, near neutrality, of sludge treated by acid processes (Stabiox and Metix-AC) is preferable before a long storage period. This allows a better biodegradation of the organic matter and the production of less odorous sludge. Sludge neutralization also decreases phosphorus and metals concentrations in drainage waters. The preservation of the acid conditions remains however useful during a short storage period, by allowing to avoid a fast resumption of the nauseous odours. Overall, the different temperatures had few effects on sludge characteristics after the 5-month storage period.
CRITICAL PERCOLATION OF FREE PRODUCT OF GROUPS
Authors: KOZÁKOVÁ IVA 
Published: June 2008

In this article we study percolation on the Cayley graph of a free product of groups.The critical probability pcof a free product G1* G2* ⋯ * Gnof groups is found as a solution of an equation involving only the expected subcritical cluster size of factor groups G1, G2, …, Gn. For finite groups this equation is polynomial and can be explicitly written down. The expected subcritical cluster size of the free product is also found in terms of the subcritical cluster sizes of the factors. In particular, we prove that pcfor the Cayley graph of the modular group PSL2(ℤ) (with the standard generators) is 0.5199…, the unique root of the polynomial 2p5- 6p4+ 2p3+ 4p2- 1 in the interval (0, 1).In the case when groups Gican be "well approximated" by a sequence of quotient groups, we show that the critical probabilities of the free product of these approximations converge to the critical probability of G1* G2* ⋯ * Gnand the speed of convergence is exponential. Thus for residually finite groups, for example, one can restrict oneself to the case when each free factor is finite.We show that the critical point, introduced by Schonmann, pexpof the free product is just the minimum of pexpfor the factors.
Comments on “The Three-Dimensional Current and Surface Wave Equations”
Authors: Ardhuin Fabrice , Jenkins Alastair D. , Belibassakis Konstadinos A. 
Published: June 2008

Abstract
The lowest order sigma-transformed momentum equation given by Mellor takes into account a phase-averaged wave forcing based on Airy wave theory. This equation is shown to be generally inconsistent because of inadequate approximations of the wave motion. Indeed the evaluation of the vertical flux of momentum requires an estimation of the pressure p and coordinate transformation function s to first order in parameters that define the large-scale evolution of the wave field, such as the bottom slope. Unfortunately, there is no analytical expression for p and s at that order. A numerical correction method is thus proposed and verified. Alternative coordinate transforms that allow a separation of wave and mean flow momenta do not suffer from this inconsistency nor do they require a numerical estimation of the wave forcing. Indeed, the problematic vertical flux is part of the wave momentum flux, thus distinct from the mean flow momentum flux, and not directly relevant to the mean flow evolution.
Observations and a Model of the Mean Circulation over the Middle Atlantic Bight Continental Shelf
Authors: Lentz Steven J. 
Published: June 2008

Abstract
Analyses of current time series longer than 200 days from 33 sites over the Middle Atlantic Bight continental shelf reveal a consistent mean circulation pattern. The mean depth-averaged flow is equatorward, alongshelf, and increases with increasing water depth from 3 cm s−1 at the 15-m isobath to 10 cm s−1 at the 100-m isobath. The mean cross-shelf circulation exhibits a consistent cross-shelf and vertical structure. The near-surface flow is typically offshore (positive, range −3 to 6 cm s−1). The interior flow is onshore and remarkably constant (−0.2 to −1.4 cm s−1). The near-bottom flow increases linearly with increasing water depth from −1 cm s−1 (onshore) in shallow water to 4 cm s−1 (offshore) at the 250-m isobath over the slope, with the direction reversal near the 50-m isobath.
A steady, two-dimensional model (no along-isobath variations in the flow) reproduces the main features of the observed circulation pattern. The depth-averaged alongshelf flow is primarily driven by an alongshelf pressure gradient (sea surface slope of 3.7 × 10−8 increasing to the north) and an opposing mean wind stress that also drives the near-surface offshore flow. The alongshelf pressure gradient accounts for both the increase in the alongshelf flow with water depth and the geostrophic balance onshore flow in the interior. The increase in the near-bottom offshore flow with water depth is due to the change in the relative magnitude of the contributions from the geostrophic onshore flow that dominates in shallow water and the offshore flow driven by the bottom stress that dominates in deeper water.
Three-Dimensional Residual Tidal Circulation in an Elongated, Rotating Basin
Authors: Winant Clinton D. 
Published: June 2008

Abstract
The three-dimensional residual circulation driven by tides in an elongated basin of arbitrary depth is described with a small amplitude, constant density model on the f plane. The inclusion of rotation fundamentally alters the residual flow. With rotation, fluid is drawn into the basin on the right side of an observer looking toward the closed end (in the Northern Hemisphere) and the return flow is on the opposite side. A lateral circulation is superposed on the axial flow, with upwelling over the deeper part of each section and downwelling near the sides. The residual flow is driven by a combination of advective terms, including the lateral advection of axial momentum associated with the Coriolis acceleration and Stokes forcing. Tidally averaged fluid parcel trajectories are determined by integrating the Lagrangian mean velocities. With or without rotation these trajectories vary considerably depending on small differences in initial position as well as on basin shape and other parameters of the problem.
Lateral Coupling in Baroclinically Unstable Flows
Authors: Spall Michael A. , Pedlosky Joseph 
Published: June 2008

Abstract
A two-layer quasigeostrophic model in a channel is used to study the influence of lateral displacements of regions of different sign mean potential vorticity gradient (Πy) on the growth rate and structure of linearly unstable waves. The mean state is very idealized, with a region of positive Πy in the upper layer and a region of negative Πy in the lower layer; elsewhere Πy is zero. The growth rate and structure of the model’s unstable waves are quite sensitive to the amount of overlap between the two regions. For large amounts of overlap (more than several internal deformation radii), the channel modes described by Phillips’ model are recovered. The growth rate decreases abruptly as the amount of overlap decreases below the internal deformation radius. However, unstable modes are also found for cases in which the two nonzero Πy regions are separated far apart. In these cases, the wavenumber of the unstable waves decreases such that the aspect ratio of the wave remains O(1). The waves are characterized by a large-scale barotropic component that has maximum amplitude near one boundary but extends all the way across the channel to the opposite boundary. Near the boundaries, the wave is of mixed barotropic–baroclinic structure with cross-front scales on the order of the internal deformation radius. The perturbation heat flux is concentrated near the nonzero Πy regions, but the perturbation momentum flux extends all the way across the channel. The perturbation fluxes act to reduce the isopycnal slopes near the channel boundaries and to transmit zonal momentum from the region of Πy &gt; 0 to the region on the opposite side of the channel where Πy &lt; 0. These nonzero perturbation momentum fluxes are found even for a mean state that has no lateral shear in the velocity field.
Freezing Drizzle Detection with WSR-88D Radars
Authors: Ikeda Kyoko , Rasmussen Roy M. , Brandes Edward , McDonough Frank 
Published: June 2008

Abstract
This study describes a freezing drizzle detection algorithm based on the Weather Surveillance Radar-1988 Doppler (WSR-88D) measured radar reflectivity. Although radar returns from freezing drizzle and light snow are similar—&lt;5 dBZ and spatially uniform—freezing drizzle can be identified using feature parameters computed from radar reflectivity, such as local and global standard deviations and reflectivity texture weighted with a fuzzy-logic scheme. Algorithm results agree well with surface precipitation reports. The proposed algorithm can serve as one component of automated decision-support schemes for icing hazard detection and/or hydrometeor identification.
Increasing prevalence and incidence of multiple sclerosis in northern Japan
Authors: Houzen H , Niino M , Hata D , Nakano F , Kikuchi S , Fukazawa T , Sasaki H 
Published: June 2008

Background We previously reported that prevalence of multiple sclerosis (MS) in Japan was 8.6/100,000 individuals in 2001. This was much higher than prevalence previously reported from Asian countries. A second epidemiologic survey was conducted to assess changes in MS prevalence and incidence over the last 30 years in Tokachi province of Hokkaido, the northernmost island of Japan. Methods The authors studied the frequency of MS in the community of Tokachi Province, where the population has stabilized between 350,000 and 360,000 over the last 30 years. The survey was conducted at the same institutions using the same methods as the first survey in 2001. Results On March 31, 2006, 47 subjects satisfied Poser’s criteria for MS. The prevalence rate increased from 8.6 to 13.1/100,000 individuals between 2001 and 2006. The prevalence of conventional MS (C-MS) increased in five years although the prevalence of optic-spinal MS (OS-MS) did not increase. The mean annual incidence increased from 0.15 (1975–1989) to 0.68 (1990–2004). Conclusions The results show the highest MS prevalence in Asia; the increase in MS prevalence in Tokachi Province may be due to increased incidence after 1990.
Timing of birth and disease progression in multiple sclerosis
Authors: Koch M , De Keyser J , Tremlett H 
Published: June 2008

Background The timing of birth has recently been associated with the risk of developing multiple sclerosis (MS) in later life. Whether the timing of birth also influences the disease course of MS is unknown. Objective To investigate whether the season or month of birth influences the timing of secondary progression or the time to landmark disability outcomes in MS. Methods To allow confirmation of findings, all analyses were performed in duplicate in two large natural history cohorts from geographically distinct but seasonally similar locations in Europe and North America. Kaplan–Meier survival analyses were used to investigate the influence of month and season of birth on 1) the time to and age at the development of secondary progression in patients with a relapsing disease onset and 2) the time to reach an Expanded Disability Status Scale (EDSS) score of 6.0 in patients with primary progressive and relapsing MS. Results No association between the month or season of birth and disease progression could be found, which was reproducible in both natural history cohorts. A seasonal trend was observed for the time to and age at secondary progression in Groningen, with March babies exhibiting a shorter time to and younger age at secondary progression. The birth month affected time to EDSS 6 for those with relapsing MS in British Columbia, with January babies exhibiting a longer time to EDSS 6. Neither finding could be reciprocated in the other natural history cohort. Conclusion The season or month of birth does not appear to influence disease progression of MS.
Neuromyelitis optica immunoglobulins as a marker of disease activity and response to therapy in patients with neuromyelitis optica
Authors: Weinstock-Guttman B , Miller C , Yeh EA , Stosic M , Umhauer M , Batra N , Munschauer F , Zivadinov R , Ramanathan M 
Published: June 2008

Objective To determine whether neuromyelitis optica (NMO) immunoglobulin (IgG) antibody status in NMO/Devic’s disease patients followed prospectively is persistent or can change relative to the clinical status and/or response to therapy. Design A cross-sectional group of patients with NMO, relapsing extensive longitudinal transverse myelitis (RLETM) or optico-spinal multiple sclerosis (OSMS) were evaluated for the presence of NMO IgG antibodies. Repeated evaluation was made in all NMO/RLETM patients and in a subgroup of OSMS patients. Setting Baird Multiple Sclerosis Center, Buffalo, New York, an academic multiple sclerosis center. Results Out of a consecutive cohort of 38 patients evaluated for the presence of NMO IgG, 12 had NMO and 26 had OSMS. Five of the 12 NMO/RLETM patients were NMO IgG positive at the time of their initial evaluation. Four of these patients were repeatedly tested for NMO IgG: two of these became negative and two remained positive. One patient who was initially negative became positive during an acute event and again became negative during the stable disease phase following treatment. A positive test result was associated with active disease, whereas a negative NMO IgG result was consistently found in stable, long-term treated patients. None of the OSMS patients were positive for NMO IgG even during acute attacks. Conclusions NMO IgG antibodies are associated with active NMO/RLETM. A well-controlled stable disease usually under effective immunosuppressive therapy can transform the NMO IgG to a negative status. Repeated NMO IgG testing should be considered as a useful biological marker for monitoring NMO/RLETM disease and or response to therapy.
Advances in understanding pathogenic mechanisms of thrombophilic disorders
Authors: Dahlbäck Björn 
Published: June 2008

AbstractVenous thromboembolism is a major medical problem, annually affecting 1 in 1000 individuals. It is a typical multifactorial disease, involving both genetic and circumstantial risk factors that affect a delicate balance between procoagulant and anticoagulant forces. In the last 50 years, the molecular basis of blood coagulation and the anticoagulant systems that control it have been elucidated. This has laid the foundation for discoveries of both common and rare genetic traits that tip the natural balance in favor of coagulation, with a resulting lifelong increased risk of venous thrombosis. Multiple mutations in the genes for anticoagulant proteins such as antithrombin, protein C, and protein S have been identified and constitute important risk factors. Two single mutations in the genes for coagulation factor V (FV Leiden) and prothrombin (20210G>A), resulting from approximately 20 000-year-old mutations with subsequent founder effects, are common in the general population and constitute major genetic risk factors for thrombosis. In celebration of the 50-year anniversary of the American Society of Hematology, this invited review highlights discoveries that have contributed to our present understanding of the systems that control blood coagulation and the genetic factors that are involved in the pathogenesis of venous thrombosis.