bluuebunny/crossref_metadata_2025 huggingface dataset:
Development of an advanced turbocharger simulation method for cycle simulation of turbocharged internal combustion engines
Authors: Zhuge W , Zhang Y , Zheng X , Yang M , He Y
Published: March 2009

An advanced turbocharger simulation method for engine cycle simulation was developed on the basis of the compressor two-zone flow model and the turbine mean-line flow model. The method can be used for turbocharger and engine integrated design without turbocharger test maps. The sensitivities of the simulation model parameters on turbocharger simulation were analysed to determine the key modelling parameters. The simulation method was validated against turbocharger test data. Results show that the methods can predict the turbocharger performance with a good accuracy, less than 5 per cent error in general for both the compressor and the turbine. In comparison with the map-based extrapolation methods commonly used in engine cycle simulation tools such as GT-POWER®, the turbocharger simulation method showed significant improvement in predictive accuracy to simulate the turbocharger performance, especially in low-flow and low-operating-speed conditions.
Simulation of CO2 storage in a heterogeneous aquifer
Authors: Ukaegbu C , Gundogan O , Mackay E , Pickup G , Todd A , Gozalpour F
Published: March 2009

The fate of carbon dioxide (CO2) injected into a deep saline aquifer depends largely on the geological structure within the aquifer. For example, low permeability layers, such as shales or mudstones, will act as barriers to vertical flow of CO2 gas, whereas high permeability channels may assist the lateral migration of CO2. It is therefore important to include permeability heterogeneity in models for numerical flow simulation

As an example of a heterogeneous system, a model of fluvial-incised valley deposits was used. Flow simulations were performed using the generalized equation-of-state model—greenhouse gas software package from Computer Modelling Group, which is a compositional simulator, specially adapted for CO2 storage. The impacts of residual gas and water saturations, gas diffusion in the aqueous phase, hysteresis, and permeability anisotropy on the distribution of CO2 between the gaseous and aqueous phases were examined. Gas diffusion in the aqueous phase was found to significantly enhance solubility trapping of CO2, even when hysteretic trapping of CO2 as a residual phase is taken into account.
Catalytic Use of Strontium Hexamethyldisilazide in the Asymmetric Michael Addition of Malonate to Chalcone Derivatives
Authors: Kobayashi Shu , Yamaguchi Miyuki , Agostinho Magno , Schneider Uwe
Published: March 2009

Strontium hexamethyldisilazide, combined with a chiral bis(sulfonamide) ligand, was found to be very effective for the catalytic asymmetric Michael addition of malonate to chalcone derivatives.
The selection of creative ideas after individual idea generation: Choosing between creativity and impact
Authors: Rietzschel Eric F. , Nijstad Bernard A. , Stroebe Wolfgang
Published: March 2009

It is commonly assumed that successful innovation depends on creative idea generation: the more ideas are generated, the higher the probability of selecting a very good idea should be. However, research has shown that people do not perform optimally at idea selection and that ideational output may not contribute much to creative idea selection. The present studies aim to explain this phenomenon. We identified the strong tendency of our participants to select feasible and desirable ideas, at the cost of originality, as the main reason for their poor selection performance. Two manipulations of participants' processing of the available ideas (exclusion instructions and quality ratings) had no effect on selection effectiveness. In contrast, explicitly instructing participants to select creative or original ideas did improve selection effectiveness with regard to idea originality, but at the same time decreased participants' satisfaction and the rated effectiveness of chosen ideas. Results are discussed in relation to an effectiveness‐originality trade off.
Intensive quantities: Why they matter to developmental research
Authors: Howe Christine , Nunes Terezinha , Bryant Peter
Published: March 2009

A distinction can be drawn between extensive and intensive quantities. Extensive quantities (e.g., volume, distance), which have been the focus of developmental research, depend upon additive combination. Intensive quantities (e.g., density, speed), which have been relatively neglected, derive from proportional relations between variables. Thus, while proportional relations can be expressed with extensive quantities, these relations are constitutive with intensive quantities. One consequence is that factors, which are theorized as marginal with extensive quantities, are conceptually central in intensive contexts, and may need to be recognized in developmental models. Two such factors, termed variable salience and relational focus, are examined here, via a study where 963 Scottish children aged 7–12 years were asked to solve 42 intensive quantity problems in comparison and missing value format. Reasoning improved with age, but at all ages it was strongly influenced by variable salience and relational focus. Moreover, the manner in which these two factors interacted with other factors differed from what might be expected from models of proportional reasoning with extensive quantities. Based upon these results, it is argued that the distinction between extensive and intensive quantities is theoretically significant, and intensive quantities need to be granted more attention in the future.
Autoantibodies to Cardiac Troponin Associate with Higher Initial Concentrations and Longer Release of Troponin I in Acute Coronary Syndrome Patients
Authors: Pettersson Kim , Eriksson Susann , Wittfooth Saara , Engström Emilia , Nieminen Markku , Sinisalo Juha
Published: March 2009

Background: Cardiac troponin (cTn) is an established marker of myocardial infarction. Pronounced heterogeneity and the minute amounts released into the circulation constitute significant challenges for cTn detection. Recently, autoantibody formation to cTn was shown to be common and to interfere with immunoassay performance. In this study, we investigated cTn autoantibodies and cardiac troponin I (cTnI) in acute coronary syndrome (ACS) patients over a 1-year period after the index event.

Methods: We used a second-generation cTnI assay designed to reduce the interference of cTn autoantibodies. The assay for cTn autoantibodies used 2 anti-cTnI antibodies to capture the ternary cTnI-complex, enabling unrestricted binding of the autoantibodies, which were detected with a labeled antihuman IgG antibody. We analyzed serum samples from 81 non–ST-elevation ACS patients taken at admission and after 1 week and 3 and 12 months.

Results: We found 14 cTn autoantibody–positive patients (21%) among the 67 cTnI-positive and none among the 14 cTnI-negative patients. Nine were autoantibody-positive at admission, and 5 became positive at 1 week. Autoantibody signals significantly increased in the 1-week and 3-month samples. At all time points, cTnI was significantly increased in the autoantibody-positive group relative to the negative group. Persistent cTnI elevations at 3 and 12 months were seen in the patients already autoantibody positive at admission.

Conclusions: During ACS, patients with cTn autoantibodies have higher cTnI release and therefore larger myocardial damage than patients without autoantibodies. Their cTnI release also lasts longer, at least months. The possible prognostic impact of these observations must be evaluated in larger clinical cohorts.
Epidemiology and pathogenesis of esophageal cancer, and the possibilities of its prevention
Authors: Hagymási Krisztina , Tulassay Zsolt
Published: March 2009

A nyelőcsőrák a hatodik leggyakoribb daganatos halálok, gyakorisága nő. A nyelőcsőrákok 95%-a laphámrák vagy adenocarcinoma. Bár a nyelőcsőlaphámrák és az adenocarcinoma szövettana és előfordulása különböző, számos kockázati tényezőjük (dohányzás, táplálkozási szokások), valamint a daganatkialakulás folyamata hasonló. A nyelőcsőrák több mint 90%-ban előrehaladott állapotban derül ki. A felismerés és a kezelés lehetőségeinek fejlődése ellenére kórjóslata rossz, az ötéves túlélés 10–13%. A kórélettani háttér pontosabb megértése a megelőzést segítheti, részben természetes hatóanyagok, részben nemszteroid gyulladáscsökkentők alkalmazásával.
The τc -topology on locally compact foundation semigroups
Authors: Ghaffari Ali
Published: March 2009

Given a foundation locally compact Hausdorff topological semigroup
S
, we consider on
Ma
(
S
)* the
τc
-topology, i.e. the weak topology under all right multipliers induced by measures in
Ma
(
S
). For such an arbitrary
S
the
τc
-topology is not weaker than the weak*-topology and not stronger than the norm topology on
Ma
(
S
)*. However, a further investigation shows that for compact
S
the norm topology and
τc
-topology coincide on every norm bounded subset of
Ma
(
S
). Among the other results we mention that except for discrete
S
the
τc
-topology is always different from the norm-topology. Finally, we give some results about
τc
-almost periodic functionals.
Cardinality restrictions on power homogeneous T5 compacta
Authors: Ridderbos Guit-Jan
Published: March 2009

We show that the cardinality of power homogeneous
T5
compacta
X
is bounded by 2
c
(
X
)
. This answers a question of J. van Mill, who proved this bound for homogeneous
T5
compacta. We further extend some results of I. Juhász, P. Nyikos and Z. Szentmiklóssy and as a corollary we prove that consistently every power homogeneous
T5
compactum is first countable. This improves a theorem of R. de la Vega who proved this consistency result for homogeneous
T5
compacta.
Incidental Capture of Juvenile Fish from an Artisanal Fishery in a Coastal Lagoon in the Gulf of California
Authors: Amezcua Felipe , Madrid-Vera Juan , Aguirre Hugo
Published: March 2009

Fishing gear used in artisanal penaeid shrimp fisheries in the southwestern Gulf of California usually consists of the trawl net, gill net, and suripera net. These net types are known to capture a high quantity of fish bycatch and are likely to cause high levels of juvenile fish mortality. However, juvenile bycatch mortality has not been documented in previous studies. The aim of this work was to study the effect of a local artisanal shrimp fishery on the juvenile fish community in the coastal lagoon of Santa Maria la Reforma, Sinaloa, Mexico. Length at first maturity was estimated for the seven most abundant species; based on this information, a generalized linear model and a Bayesian approach were used to estimate the probabilities of juvenile fish capture for different types of fishing gear. We found that the three net types captured juveniles, even those of species maturing at small lengths, and were likely to impact the recruitment of the analyzed species, as the probability of juvenile capture by the nets ranged from 0.20 to 0.90. However, the species for which sexual maturity was attained at a smaller length were less vulnerable to the fishing gear types analyzed. The gill net and trawl net had the highest probabilities of capturing juveniles in general, whereas the suripera net showed a high probability of capturing juveniles belonging to certain species. Incidentally, the suripera net is the gear used most frequently in the area to catch shrimp.
Natural Mortality Rates during Life History Stages of the Red Grouper on Campeche Bank, Mexico
Authors: Giménez-Hurtado Enrique , Arreguín-Sánchez Francisco , Lluch-Cota Salvador E.
Published: March 2009

The objective of this study was to arrive at biologically convincing estimates of the natural mortality rate (M) for different life history stages of the red grouper Epinephelus morio on Campeche Bank, Mexico. Estimates of M must be compatible with our knowledge of life histories and are essential as input to analytical assessment models for any exploited stock. Because of difficulties in estimating M directly, M has often been incorrectly assumed to be constant with age for a fishery harvesting different age-groups. The gnomonic interval method (GIM) was applied to this long-lived species to estimate a vector of M-values for successive life history stages. The GIM estimates the vector of M at age from the duration of successive development stages and the mean annual fecundity. Estimates were calibrated using available independent data. We computed the relationship between M and age (t) over a 13-year period as Mt = 0.8976t−0.93. Values of M estimated by GIM for adult red grouper were not significantly different (P > 0.05) from those reported in the literature.
Sulfur Cinquefoil (Potentilla recta) Seed Ecology: Seed Bank Survival and Water and Salt Stresses on Germination
Authors: Kiemnec Gary L. , McInnis Michael L.
Published: March 2009

Sulfur cinquefoil, a perennial invasive weed of many different habitats in the United States, reproduces and spreads predominately through seed production, making seed bank survival and successful germination essential steps in the invasive process. To evaluate its potential to invade water-stressed environments, field and growth chamber studies were conducted in two areas of sulfur cinquefoil seed ecology: (1) monitoring the seed bank population and (2) determining the effect of salt and water stresses on germination of two sulfur cinquefoil seed populations differing in site characteristics of precipitation, temperature, and soil conditions. Field sampling demonstrated that a 2-yr average seed rain of 73,700 seeds m−2 resulted in an average 26,600 seeds m−2 annual increase in the seed bank. Regression analysis showed seed rain accounted for only 7 and < 1% of the variation in seedling density in 2003 and 2004, respectively. Seeds from the two populations showed a difference in the level of decrease in germination in response to increasing water and salt stresses. Managers should be aware that some populations of sulfur cinquefoil may be able to survive under drier or saltier conditions than previously thought. It appears that several years of control of mature sulfur cinquefoil would dramatically reduce the sulfur cinquefoil seed bank.
Augmentative Restoration: Repairing Damaged Ecological Processes During Restoration of Heterogeneous Environments
Authors: Sheley Roger L. , James Jeremy J. , Bard Erin C.
Published: March 2009

Heterogeneity in disturbance regimes, propagule pools, and factors affecting plant performance are a ubiquitous feature of wildlands. We tested a conceptual framework, termed augmentative restoration, aimed at identifying and selectively repairing or replacing damaged processes based on their predicted influence on the three causes of succession: site availability, species availability, and species performance. This framework was tested at three sites each with a different cause of succession naturally occurring in an ephemeral wetland dominated by invasive plants that had varying levels of disturbance (site availability), remnant native plants (species availability), and water availability (species performance). Our hypotheses were (1) seeding combined with watering would augment meadow vole disturbance to increase desired species composition, (2) shallow tilling combined with watering would augment remnant native species, and (3) shallow tilling combined with seeding would augment mesic soils to increase desired species composition. Shallow tilling, watering, and seeding were applied in a factorial arrangement at all three sites. These eight treatment combinations were applied in a split-plot design with four replications to generate 32 whole plots (2 m2). The herbicide 2,4-D was applied on half of each whole plot to influence relative species performance. In two of the three sites, using augmentative restoration to guide our management approaches improved our decision as to the treatment combinations that would maximize seedling establishment. Selectively augmenting successional processes that remain intact by repairing or replacing processes occurring at inadequate levels can improve implementation of successional management and provide a refined process-based framework for restoration across heterogeneous landscapes. Besides the clear economic advantages of lower management inputs associated with augmentative restoration, avoiding unnecessary management inputs has the additional advantage of minimizing unintended negative impacts on ecosystem processes.
Taxonomic Confusion Permits the Unchecked Invasion of Vernal Pools in California by Low Mannagrass (Glyceria declinata)
Authors: Gerlach John D. , Bushman B. Shaun , McKay John K. , Meimberg Harald
Published: March 2009

Chloroplast DNA sequences and recently established morphological characters were used to confirm the widespread invasion of California's vernal pools by European low mannagrass. Morphological similarities between low mannagrass and western mannagrass have led to different taxonomic treatments, depending on the geographical extent of a particular flora. When California's flora was last revised, the two species were combined as western mannagrass, which was then considered to be a native species. Unfortunately, the revised flora was published just as low mannagrass began to rapidly expand its range within the state and, because it was considered to be a native species in the new flora, no actions were initiated to limit the invasion. Our data show that low mannagrass was present at all localities in the Central Valley of California that were investigated, indicating a widespread and undetected invasion. The invasion has led to a degradation of the vernal pool ecosystems, which are the habitat of many federal and state protected endangered and threatened species.
A Comparison of Inter- and Intraspecific Interference on Broom Snakeweed (Gutierrezia sarothrae) Seedling Growth
Authors: Thacker Eric , Ralphs Michael H. , Monaco Thomas A.
Published: March 2009

Broom snakeweed (snakeweed) is a native range shrub found throughout semiarid rangelands of the western United States, which increases and dominates plant communities after disturbances such as overgrazing, drought, or wildfire. The objective of this study was to compare the ability of selected grass species and prostrate kochia to restrict establishment and growth of snakeweed seedlings in potted-plant and replicated field studies within two sagebrush ecological sites. In the potted-plant studies, single snakeweed seedlings were grown with seedlings (seedling neighbor study) and established plants (established neighbor study) of three cool-season grasses (crested, pubescent, and bluebunch wheatgrass), prostrate kochia, and snakeweed at increasing densities (1, 3, 5 plants/pot). Interference from crested wheatgrass in the seedling neighbor study, and both crested and bluebunch wheatgrass in the established neighbor study, induced the greatest mortality of snakeweed seedlings, and snakeweed growth was suppressed more by interspecific (grass) than intraspecific (snakeweed) neighbors in both potted-plant studies. Snakeweed establishment was also evaluated at two field sites: Howell and Nephi, UT. Snakeweed and downy brome were controlled by picloram (0.25 kg ae/ha) and glyphosate (1.5 kg ae/ha), then three native and three introduced grasses were drill-seeded, and prostrate kochia was dribble-seeded in replicated plots (3 m by 15 m) at both sites in October 2003. Snakeweed seedlings were transplanted into seeded plots and a bare ground control plot in autumn 2004. Snakeweed mortality was greatest (73%) in crested wheatgrass plots at Howell, but there were few differences among species treatments at Nephi. Of the snakeweed seedlings that survived, there was relatively little growth in any of the seeded plots compared to those in the bare ground control plots. These results indicate that seeded cool-season grasses interfered with and reduced establishment of snakeweed seedlings.
Ductal Intraepithelial Neoplasia: Postsurgical Outcome for 1,267 Women Cared for in One Single Institution over 10 Years
Authors: Guerrieri-Gonzaga Aliana , Botteri Edoardo , Rotmensz Nicole , Bassi Fabio , Intra Mattia , Serrano Davide , Renne Giuseppe , Luini Alberto , Cazzaniga Massimiliano , Goldhirsch Aaron , Colleoni Marco , Viale Giuseppe , Ivaldi Giovanni , Bagnardi Vincenzo , Lazzeroni Matteo , Decensi Andrea , Veronesi Umberto , Bonanni Bernardo
Published: March 2009

Learning Objectives

Summarize the main risk factors for breast cancer recurrence in patients with DIN. Evaluate the role of radiotherapy in patients with DIN. Compare the potential benefit of treating patients with low-dose tamoxifen with the risks and benefits of other treatments.

This article is available for continuing medical education credit at CME.TheOncologist.com.
Low level outlets 3: British Waterways' approach
Authors: Brown David H.
Published: March 2009

British Waterways' portfolio of old dams is described and contemporary valve layouts are discussed. The risks associated with such layouts are reviewed as are recent recommendations by inspecting engineers for mitigating these risks. British Waterways' emergency drawdown policy is stated and three recent examples of pipelining are described. Finally, lessons learnt by British Waterways from the Boltby and Ulley incidents are summarised.
Examination of the Mechanism of Phenanthrenequinone Toxicity To Vibrio Fischeri: Evidence for a Reactive Oxygen Species-Mediated Toxicity Mechanism
Authors: Wang Wenxi , Nykamp Julie , Huang Xiao-Dong , Gerhardt Karen , Dixon D. George , Greenberg Bruce M.
Published: March 2009

Phenanthrenequinone (PHQ) is a photoproduct of phenanthrene, one of the most prevalent polycyclic aromatic hydrocarbons in the environment. Phenanthrenequinone is a compound of substantial interest, because its toxicity can be much greater than its parent chemical to aquatic organisms. The toxicity mechanisms of PHQ to the luminescent marine bacterium Vibrio fischeri were examined in the present study. Phenanthrenequinone can redox cycle in bacterial cells and transfer electrons to O2, enhancing the production of superoxide (O•−2), hydrogen peroxide (H2O2), and other reactive oxygen species (ROS). Exposure of cells to PHQ increased activity of superoxide dismutase (SOD), which detoxifies the ROS superoxide. Concentrations of PHQ that induced the production of H2O2 and other ROS, as well as the elevated levels of Fe-SOD, were correlated with its toxicity as measured by luminescence. Furthermore, toxicity of PHQ to V. fischeri was lowered under the anaerobic conditions, suggesting that the absence of oxygen, which would limit the production of ROS, alleviated toxicity of PHQ. Thus, a ROS-mediated toxicity mechanism of PHQ is highly implicated by in the present study.
Effect of cation competition on cadmium uptake from solution by the earthworm Eisenia Fetida
Authors: Li Lian-Zhen , Zhou Dong-Mei , Wang Peng , Jin Sheng-Yang , Peijnenburg Willie J.G.M. , Reinecke Adriaan J. , van Gestel Cornelis A.M.
Published: March 2009

Metal speciation alone is insufficient to predict metal accumulation in aquatic and terrestrial organisms, because competition between cations can play an important role. In the present study, the effects of competing cations (Ca2+,Mg2+,and H+) on Cd uptake by the earthworm Eisenia fetida were quantified through short-term experiments over a large Cd concentration range in aqueous exposure solutions. Free Cd2+ activity was a better predictor for Cd accumulation in the earthworms than was total Cd concentration in solution, thus supporting the free ion activity model. The presence of the other cations at environmentally pertinent concentrations inhibited Cd uptake to different degrees. A competitive equilibrium model based on the biotic ligand model was developed to quantify the effect of the cations. The model parameters are the conditional constants for binding of H+ (log K = 4.97), Ca2+ (log K = 3.00), and Mg2+ (log K = 2.64) to the biological uptake sites of E. fetida. Autovalidation of the model with experimental results showed that 48-h Cd accumulation in the earthworm could be successfully predicted with activities of free Cd2+ and the major cations (Ca2+,Mg2+,and H+) as input.
Limitations in Determining Multifractal Spectra from Pore–Solid Soil Aggregate Images
Authors: Kravchenko A. N. , Martín M. A. , Smucker A. J. M. , Rivers M L.
Published: March 2009

Multifractal methods have the potential to be useful tools for characterizing spatial distributions of soil pores from microtomographic images of undisturbed soil cores and soil aggregates. The objective of this study was to examine the limitations of multifractal analyses in binary (void and solid) soil images and to explore conditions under which multifractal spectra can be obtained. Multifractal characteristics of binary soil images are bounded within certain limiting values corresponding to nonfractal scaling. In this study, we first addressed the theoretical limitations of multifractal analysis of binary images and examined the nonfractal scaling boundaries in multifractal calculations by the method of moments. Then we developed boundary conditions for multifractal calculations by the direct method. Results revealed that fractal scaling is potentially possible only across a relatively narrow range of cell sizes restricted by the nonfractal scaling boundaries. Moreover, the range of cell sizes where fractal scaling is potentially possible varies with pore size. That is, in multifractal calculations it changes continuously with changes in the q value. For the soil aggregates examined in this study, this range varied from two to eight pixels for low q values to 128 pixels for high q values. The varying range makes calculations of true multifractal spectra for binary soil image data impossible. These results are consistent with a general theoretical notion that binary soil images are not multifractal in a strict mathematical sense. We suggest, however, that application of multifractal formalism can generate “pseudo‐multifractal spectra” that might still be useful for summarizing pore distribution information and for comparing pore data among different agricultural management regimes and soil types.
Lacunarity and Fractal Analyses of Soil Macropores and Preferential Transport Using Micro‐X‐Ray Computed Tomography
Authors: Luo Lifang , Lin Henry
Published: March 2009

Quantification of soil macropore networks and solute transport patterns is important to enhance our understanding of preferential flow in structured soils. We investigated soil macropore structure and solute transport dynamics in an intact soil column of 76‐mm diameter and 265‐mm length. Five positions (each with a thickness of 10.7 mm) in the soil column were scanned with a voxel resolution of 78.1 by 78.1 by 86.7 μm using micro‐x‐ray computed tomography. The scanning was done at three stages after the soil column was satiated: (i) before tracer (KI) introduction, (ii) 6 min after tracer introduction, and (iii) 78 min after tracer introduction. The macropore network and tracer distribution were reconstructed at the five scanned positions. Relative lacunarity functions (RLFs) and pore fractal dimensions, in both two and three dimensions, were calculated. Distinct macropore characteristics and flow patterns were observed at the five positions. The biopores were active in solute transport because of their high continuity and low tortuosity. Positive logarithmic trends were found between the fractal dimension and the volume percentage of the macropores and tracer distribution. Generally, the lacunarity function reflected the size distribution of macropores and the spatial pattern of flow and transport. The RLFs indicated that the tracer distributions exhibited more self‐similarity than the macropore networks and that the representative elementary volume had not been reached for the three‐dimensional macropore networks within the size range investigated (cube size ≤63). Lacunarity has diagnostic value in characterizing soil macropore structure and flow pattern and may be coupled with the fractal dimension to better describe and model soil structural properties.
On the Physical Properties of Apparent Two‐Phase Fractal Porous Media
Authors: Yu Boming , Cai Jianchao , Zou Mingqing
Published: March 2009

In this study, we summarized some basic characters of fractal porous media, including the fractal pore or particle size distribution, pore or particle density function, the fractal dimensions for the pore and solid phases, and their relations. The geometric porosities vs. the fractal dimensions and microstructures of porous media were reviewed and discussed in two and three dimensions. The specific surface areas of fractal porous media in two and three dimensions were derived and were expressed as a function of the fractal dimensions and microstructural parameters. The fluid velocities in fractal porous media were also derived and found to be a function of the fractal dimensions and microstructural parameters of the medium. The parameters presented are the fundamental ones and may have potential in analysis of transport properties in fractal porous media.
Modeling Dynamic Fragmentation of Soil
Authors: Bird N. R. A. , Watts C. W. , Tarquis A. M. , Whitmore A. P.
Published: March 2009

Soil fragmentation is a critical component in determining the structure of soil at any instant in time. Modeling and describing soil fragmentation consequently occupies an important niche in soil research. Recent attention has focused on a simple deterministic model of soil fragmentation that encompasses the notion of scale invariance and yields characteristic power‐law or fractal size distributions. This model lacks a temporal component, which means that its applicability to a host of real scenarios, involving progressive comminution of soil in time, appears restricted. Our purpose in this study was to generalize this deterministic approach to modeling fragmentation by explicitly including time and by relaxing the requirement for scale invariance. We examined the consequences of these simple modifications in terms of the evolving fragment size distributions. We investigated the development of three different outcomes. The first is a skewed unimodal distribution of the logarithm of fragment size. The second is a unimodal distribution well approximated by the lognormal distribution, and the third is a local power‐law distribution. The outcome was dependent on the choice of how fragmentation was modeled as a function of scale. We concluded that power‐law distributions should be regarded as the exception rather than the rule in a temporal fragmentation of soil and that we should expect to find power‐law scaling locally rather than across the full range of fragment sizes.
Development of a Low‐Cost Wastewater Treatment System for Small‐Scale Wineries
Authors: Arienzo Michele , Christen Evan W. , Quayle Wendy , Di Stefano Nicola
Published: March 2009

A pilot‐scale winery wastewater treatment system was developed to treat wastewater produced by a small winery (approximately 1200 metric tons of grapes crushed). The pilot system consisted of a sedimentation/aerobic process combined with a bioremediation wastewater cell planted with Juncus ingens. The main design specifications, detailed descriptions of the plant, and analysis of the influent and effluent characteristics (pH, electrical conductivity, total suspended solids, chemical oxygen demand [COD], etc.) are reported for each segment of the system. Over the study period, the mean winery wastewater flowrate was 3.5 m 3/d at organic loads of 5000 to 14 000 mg‐COD/L. The study measured average removal rates of 72% for COD and 65% for total organic carbon and dissolved carbon. The application of wastewater to the soil increased the soil salinity in the top 30 cm, but remained stable below this. The system also seemed to be effective at neutralizing the pH of the acidic winery wastewater and at removing the phosphorus pool (65%) in the wastewater, whereas the levels of nitrogen and most of the cations increased in the treated effluent. The absorbing/adsorbing and degradation capacity of the soil of the wastewater bioremediation cell did not appear to be exhausted after one vintage. Juncus ingens appeared to grow moderately well, until the end of the vintage, when dieback began to occur. An infilling with organic matter of the surface soil layer under the root zone was observed, which reduced water infiltration and hence system treatment capacity. The data provide evidence that this is a potentially effective wastewater treatment approach for small wineries located in rural areas.
Effect of Oxygen Partial Pressure and Chemical Oxygen Demand Loading on the Biofilm Properties in Membrane‐Aerated Bioreactors
Authors: Zhu I. X. , Allen D. G. , Liss S. N.
Published: March 2009

Membrane‐aerated biofilms with oxygen and nutrients diffusing from the opposite sides possess distinct properties, including the ability to couple aerobic and anaerobic processes. The objective of this study was to examine the effects of oxygen partial pressure and chemical oxygen demand (COD) loading on biofilm properties. Two laboratory‐scale membrane‐aerated bioreactors were operated for a total of 283 days, with one reactor operated at 42, 60, and 89 kPa (0.41, 0.59, and 0.88 atm) oxygen, and the other reactor at 25 kPa (0.25 atm) oxygen (air control). The biofilm detached at the oxygen partial pressures of 60 and 89 kPa (0.59 and 0.88 atm) at a COD loading of 11.3 kg COD/1000 m 2/d, but was sustained at the oxygen partial pressures of 25 and 42 kPa (0.25 and 0.41 atm), with a porous structure at the membrane interface at the COD loading of 11.3 kg COD/1000 m 2/d. Biofilm formation was improved at a higher COD loading. It is proposed that the loss of extracellular polymeric substances at the biofilm bottom is the cause for the biofilm detachment subjected to a higher oxygen partial pressure.
Biological Denitrification Using Corncobs as a Carbon Source and Biofilm Carrier
Authors: Xu Zu‐xin , Shao Liu , Yin Hai‐long , Chu Hua‐qiang , Yao Yi‐jun
Published: March 2009

In this research, agricultural waste—in particular, corncobs—was investigated for use as the sole carbon source and biofilm carrier to remove nitrate from wastewater in up‐flow laboratory reactors. An artificial wastewater with a temperature range of 27 to 33°C was used. Fast startup of the reactor and a high nitrate removal efficiency were observed. The highest denitrification rate of 0.203kg/(m 3 · d) was achieved when flow rate and nitrate concentration were 153 L/d and 25.3 mgN/L, respectively. The accumulation of nitrite was not observed in this process. Moreover, flow rate and nitrate concentration of the influent were observed to have a significant effect on nitrate removal efficiency. A sharp decline of nitrate removal efficiency was observed when the flow rate was greater than 50 L/d. The reactor had the ability to accommodate a wide range of pH levels (6.5 to 8.5) and dissolved oxygen (1.5 mg/L to 4 mg/L). A time‐dependent decrease in nitrate removal efficiency was observed after 67 days of operation. The addition of fresh corncobs brought about a rapid increase of nitrate removal efficiency. Results showed that corncobs could be used as an economical and effective carbon source for denitrification.
Comparison of Performance and Operation of Side‐By‐Side Integrated Fixed‐Film and Conventional Activated Sludge Processes at Demonstration Scale
Authors: Stricker Anne‐Emmanuelle , Barrie Ashley , Maas Carol L. A. , Fernandes William , Lishman Lori
Published: March 2009

A full‐scale demonstration of an integrated fixed‐film activated sludge (IFFAS) process with floating carriers has been conducted in Ontario, Canada, since August 2003. In this study, data collected on‐site from July 2005 to December 2006 are analyzed and compared with the performance of a conventional activated sludge train operated in parallel. Both trains received similar loadings and maintained comparable mixed liquor concentrations; however, the IFFAS had 50% more biomass when the attached growth was considered. In the winter, the conventional train operated at the critical solids retention time (SRT) and had fluctuating partial nitrification. The IFFAS nitrified more consistently and had a doubled average capacity. In the summer, the suspended SRT was less limiting, and the benefit of IFFAS for nitrification was marginal. The lessons learned from the operational requirements and challenges of the IFFAS process (air flow, carrier management, and seasonal foaming) are discussed, and design recommendations are proposed for whole plant retrofit.
Effect of Sonication on Electro‐Oxidation of Organic Pollutants in Saline Wastewater
Authors: Sundarapandiyan S. , Sivakumar V. , Rajeswari G. , Saravanan P.
Published: March 2009

The aim of this work is to study the effect of ultrasound in pollution attenuation during electro‐oxidation. Attenuation of chemical oxygen demand (COD) and total Kjeldahl nitrogen (TKN) with and without sonication during electro‐oxidation was studied. Further, the power of ultrasound during electro‐sonication was varied, and its effect on attenuation of COD and TKN was studied. It was found that introduction of sonication could enhance pollution attenuation. It was also observed that pollution attenuation was proportional to the power of ultrasound. A significant level of pollution attenuation was attained during first 15 minutes of electro‐sonication. Total current efficiency and anode efficiency were found to be proportional to the power of ultrasound, up to 100 W. Increasing the power more than 100 W did not render a significant increase in the total current efficiency and anode efficiency. Energy consumption for electro‐oxidation was found to be inversely proportional to the power of ultrasound, up to 100 W.
Biodegradation and Detoxification of Reactive Textile Dye by Isolated Pseudomonas sp. SUK1
Authors: Kalyani Dayanad C. , Telke Amar A. , Govindwar Sanjay P. , Jadhav Jyoti P.
Published: March 2009

An isolated bacterium from a textile disposal site, Pseudomonas sp. SUK1, has the ability to decolorize the reactive textile dyes and methyl orange. This bacterium showed the potential to decolorize the textile dye Reactive Blue 59 at a high concentration (5 g/L −1), which is frequently used in the textile industry of Solapur, India. Induction in the activities of lignin peroxidase, azoreductase, and dichlorophenol indophenol reductase was observed during the decolorization of Methyl Orange and Reactive Blue 59. Methyl Orange (as model azo dye) was used to understand the mechanism of biodegradation by Pseudomonas sp. SUK1. The final product was identified as 1,4‐benzenediamine, N, N‐dimethyl by gas chromatography‐mass spectroscopy. Microbial and phytotoxicity studies revealed the nontoxic nature of the products of Reactive Blue 59.
Acting White or Acting Black: Mixed-Race Adolescents' Identity and Behavior
Authors: Ruebeck Christopher S , Averett Susan L , Bodenhorn Howard N
Published: March 2009

Although rates of interracial marriage are on the rise, we still know relatively little about the experiences of mixed-race adolescents. In this paper, we examine the identity and behavior of mixed-race (black and white) youth. We find that mixed-race youth adopt both types of behaviors, those that can be empirically characterized as black and those that can be characterized as white. When we combine both types of behavior, average mixed-race behavior is a combination that is neither white nor black, and the variance in mixed-race behavior is generally greater than the variance in behavior of monoracial adolescents, especially as compared to the black racial group. Adolescence is the time during which there is most pressure to establish an identity, and our results indicate that mixed-race youth are finding their own distinct identities, not necessarily joining either monoracial group, but in another sense joining both of them.
Statistical physics for cosmic structures; A. Gabrielli, F. Sylos Labini, M. Joyce and L. Pietronero; Springer, Berlin, 2005
Authors: Grujic Petar
Published: March 2009

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Short-Term Exercise Training Does Not Stimulate Skeletal Muscle ATP Synthesis in Relatives of Humans With Type 2 Diabetes
Authors: Kacerovsky-Bielesz Gertrud , Chmelik Marek , Ling Charlotte , Pokan Rochus , Szendroedi Julia , Farukuoye Michaela , Kacerovsky Michaela , Schmid Albrecht I. , Gruber Stephan , Wolzt Michael , Moser Ewald , Pacini Giovanni , Smekal Gerhard , Groop Leif , Roden Michael
Published: March 2009

OBJECTIVE

We tested the hypothesis that short-term exercise training improves hereditary insulin resistance by stimulating ATP synthesis and investigated associations with gene polymorphisms.

RESEARCH DESIGN AND METHODS

We studied 24 nonobese first-degree relatives of type 2 diabetic patients and 12 control subjects at rest and 48 h after three bouts of exercise. In addition to measurements of oxygen uptake and insulin sensitivity (oral glucose tolerance test), ectopic lipids and mitochondrial ATP synthesis were assessed using1H and31P magnetic resonance spectroscopy, respectively. They were genotyped for polymorphisms in genes regulating mitochondrial function, PPARGC1A (rs8192678) and NDUFB6 (rs540467).

RESULTS

Relatives had slightly lower (P = 0.012) insulin sensitivity than control subjects. In control subjects, ATP synthase flux rose by 18% (P = 0.0001), being 23% higher (P = 0.002) than that in relatives after exercise training. Relatives responding to exercise training with increased ATP synthesis (+19%, P = 0.009) showed improved insulin sensitivity (P = 0.009) compared with those whose insulin sensitivity did not improve. A polymorphism in the NDUFB6 gene from respiratory chain complex I related to ATP synthesis (P = 0.02) and insulin sensitivity response to exercise training (P = 0.05). ATP synthase flux correlated with O2uptake and insulin sensitivity.

CONCLUSIONS

The ability of short-term exercise to stimulate ATP production distinguished individuals with improved insulin sensitivity from those whose insulin sensitivity did not improve. In addition, the NDUFB6 gene polymorphism appeared to modulate this adaptation. This finding suggests that genes involved in mitochondrial function contribute to the response of ATP synthesis to exercise training.
Neuroprosthesis Peroneal Functional Electrical Stimulation in the Acute Inpatient Rehabilitation Setting: A Case Series
Authors: Dunning Kari , Black Kristy , Harrison Andrea , McBride Keith , Israel Susan
Published: March 2009

Background and Purpose

Studies have suggested that peroneal nerve functional electrical stimulation (peroneal FES) during walking improves gait in patients with chronic stroke. The effect of peroneal FES during the acute stages of stroke recovery is not known. The purposes of this case report are: (1) to describe differences between walking with and without a neuroprosthesis during the first few weeks after stroke, (2) to offer a clinical perspective on decision making for the use of peroneal FES during acute rehabilitation, and (3) to determine the feasibility of rehabilitation with peroneal FES neuroprostheses during the acute phases of stroke recovery.

Case Description

This case report describes 2 patients with different clinical presentations but both receiving inpatient rehabilitation less than 2 weeks after stroke. Each patient received peroneal FES via a neuroprothesis as tolerated while gait training in therapy.

Outcomes

One patient immediately increased gait speed (128%) and decreased time to perform the Timed “Up & Go” Test (40%) using the neuroprothesis. Both patients immediately increased the 6-Minute Walk Test distance using the neuroprothesis (121% and 101%). The patient who underwent testing with the instrumented walking system also demonstrated improved gait symmetry. After 1 to 3 weeks of using the neuroprothesis, the difference between outcomes with and without the neuroprothesis decreased.

Discussion

It is possible that peroneal FES delivered through a neuroprosthesis during acute stroke recovery may improve gait outcomes. Research is needed to determine proper duration and timing.
On “tribes” and bribes
Authors: González Roberto J.
Published: March 2009

The concept of the “tribe” has captured the imagination of military planners, who have been inspired partly by social scientists. Interest in tribes stems from events in Iraq's al-Anbar province, where the US military has co-opted Sunni “tribal” leaders. Some social scientists have capitalized on these developments by doing contract work for the Pentagon. For example, the “Iraq tribal study”—prepared by a private company consisting of anthropologists and political scientists among others—suggests employing colonial-era techniques (such as divide and conquer) for social control. It also advocates bribing local leaders, a method that has become part of the US military's pacification strategy. Such imperial policing techniques are likely to aggravate armed conflict between and among ethnic groups and religious sects. Observers report that the US strategy is creating a dangerous situation resembling the Lebanese civil war, raising ethical questions about social scientists' involvement in these processes.
Outcome of using the histological pseudocapsule as a surgical capsule in Cushing disease
Authors: Jagannathan Jay , Smith Rene , DeVroom Hetty L. , Vortmeyer Alexander O. , Stratakis Constantine A. , Nieman Lynnette K. , Oldfield Edward H.
Published: March 2009

Object

Many patients with Cushing disease still have active or recurrent disease after pituitary surgery. The histological pseudocapsule of a pituitary adenoma is a layer of compressed normal anterior lobe that surrounds the adenoma and can be used during surgery to identify and guide removal of the tumor. In this study the authors examined the results of using the pseudocapsule as a surgical capsule in the resection of adenomas in patients with Cushing disease.

Methods

The authors reviewed a prospective database of data obtained in patients with Cushing disease who underwent surgery. The analysis included all cases in which a lesion was identified during surgery and in which the lesion was believed to be confined to the pituitary gland in patients with Cushing disease between January 1990 and March 2007. Since the objective was to determine the success of using the pseudocapsule as a surgical capsule, patients with invasive tumors and patients in whom no lesion was identified during surgery—challenging cases for surgical success—were excluded from analysis.

Results

In 261 patients an encapsulated adenoma was identified at surgery. Tumor was visible on MR imaging in 135 patients (52%); in 126 patients (48%) MR imaging detected no tumor. The range of tumor size overlapped considerably in the groups with positive and negative MR imaging results, indicating that in addition to size other features of the adenoma influence the results of MR imaging. In 252 patients hypercortisolism resolved after the first operation, whereas in 9 patients (3 with positive MR imaging and 6 with negative MR imaging) early reoperation was required. Hypercortisolism resolved in all 261 patients (256 with hypocortisolism and 5 with eucortisolism) before hospital discharge. Forty-six patients (18%) had postoperative electrolyte abnormalities (30 with hyponatremia and 16 with diabetes insipidus), but only 2 patients required treatment at discharge. The mean clinical follow-up duration was 84 months (range 12–215 months). Six patients (2%) had recurrence of hypercortisolism, all of whom were treated successfully with reoperation.

Conclusions

Because of their small size, adenomas can be challenging to identify in patients with Cushing disease. Use of the histological pseudocapsule of an adenoma allows accurate identification of the tumor and helps guide its complete excision. With this approach the overall remission rate is high and the rate of complications is low.