bluuebunny/crossref_metadata_2025_split huggingface dataset:
The dynamic process of cognitive mapping in the absence of visual cues:human data compared with animal studies
Authors: Yaski Osnat , Portugali Juval , Eilam David 
Published: July 2009

SUMMARY
The present study aimed to investigate the behavior involved in constructing spatial representation in humans. For this, blindfolded adult human subjects were introduced into an unfamiliar environment, where they were requested to move incessantly for 10 min. Analysis of the locomotor activity of the participants revealed the following exploratory behaviors: (1)`looping'; (2) `wall-following'; (3) `step-counting'; (4) `cross-cutting'; and(5) `free traveling'. Looping is a typical exploratory mode of sightless explorers, based on returning to a recently traveled place. Wall-following is common in enclosed spaces, whereby explorers follow the perimeter of the environment. Both looping and wall-following are based on an egocentric frame of reference by which explorers obtain information about the shape, size and landmarks in the environment. Blindfolded explorers displayed step-counting in order to scale the environment and the relationships in it. Altogether,exploration by looping, wall-following and step-counting resulted in an allocentric spatial representation. The acquisition of spatial representation was manifested by cross-cutting and free travel, with subjects walking in a relatively fast and decisive manner. In light of the above modes of activity,we suggest that exploration of an unfamiliar environment is a synergetic self-organized process (synergetic inter-representation networks, SIRN model);an interplay between external and internal representations. According to this model, the interplay gives rise to an order parameter, such as the environment's dimensions or geometry, enabling progression to a subsequent exploratory behavior. This dynamic and sequential interplay reaches a steady state when a spatial representation (i.e. `cognitive map') is established.
Alternative oxidase in animals: unique characteristics and taxonomic distribution
Authors: McDonald Allison E. , Vanlerberghe Greg C. , Staples James F. 
Published: July 2009

SUMMARYAlternative oxidase (AOX), a ubiquinol oxidase, introduces a branch point into the respiratory electron transport chain, bypassing complexes III and IV and resulting in cyanide-resistant respiration. Previously, AOX was thought to be limited to plants and some fungi and protists but recent work has demonstrated the presence of AOX in most kingdoms of life, including animals. In the present study we identified AOX in 28 animal species representing nine phyla. This expands the known taxonomic distribution of AOX in animals by 10 species and two phyla. Using bioinformatics we found AOX gene sequences in members of the animal phyla Porifera, Placozoa, Cnidaria, Mollusca, Annelida,Nematoda, Echinodermata, Hemichordata and Chordata. Using reverse-transcriptase polymerase chain reaction (RT-PCR) with degenerate primers designed to recognize conserved regions of animal AOX, we demonstrated that AOX genes are transcribed in several animals from different phyla. An analysis of full-length AOX sequences revealed an amino acid motif in the C-terminal region of the protein that is unique to animal AOXs. Animal AOX also lacks an N-terminal cysteine residue that is known to be important for AOX enzyme regulation in plants. We conclude that the presence of AOX is the ancestral state in animals and hypothesize that its absence in some lineages,including vertebrates, is due to gene loss events.
Elemental and configural processing of odour mixtures in the newborn rabbit
Authors: Coureaud Gérard , Hamdani Younes , Schaal Benoist , Thomas-Danguin Thierry 
Published: July 2009

SUMMARYThe processing of odour mixtures by young organisms is poorly understood. Recently, the perception of an AB mixture, known to engage configural perception in adult humans, was suggested also to be partially configural in newborn rabbits. In particular, pups did not respond to AB after they had learned A or B. However, two alternative hypotheses might be suggested to explain this result: the presence in the mixture of a novel odorant that inhibits the response to the learned stimulus, and the unevenness of the sensory and cognitive processes engaged during the conditioning and the behavioural testing. We conducted four experiments to explore these alternative hypotheses. In experiment 1, the learning of A or B ended in responses to mixtures including a novel odorant (AC or BC). Experiment 2 pointed to the absence of overshadowing. Therefore, a novelty effect cannot explain the non-response to AB after the learning of A or B. In experiment 3,pups having learned A or B in AC or BC did not respond to AB. However, they generalized odour information acquired in AB to AC or BC in experiment 4. Thus, the balancing of the perceptual tasks between the conditioning and retention test does not enhance the response to the AB mixture. To sum up, the present experiments give concrete support to the partially configural perception of specific odour mixtures by newborn rabbits.
Proximity Ligation Measurement of the Complex between Prostate Specific Antigen and α1-Protease Inhibitor
Authors: Zhu Lei , Koistinen Hannu , Landegren Ulf , Stenman Ulf-Håkan 
Published: July 2009

Abstract
Background: Prostate specific antigen (PSA)–α1-protease inhibitor complex (PSA-API) is a minor form of PSA in serum. It may be useful for prostate cancer (PCa) diagnosis, but its specific detection is hampered by nonspecific background. To avoid this, we developed an immunoassay for PSA-API based on proximity ligation.
Methods: We used a monoclonal antibody (mAb) to total PSA (tPSA) to capture PSA, while using another anti-tPSA mAb together with an anti-API mAb as probes. We measured PSA-API by quantification of amplified DNA strands conjugated to the probes. We measured serum PSA-API in 84 controls and 55 men with PCa who had PSA concentrations of 4.0–10 μg/L.
Results: The detection limit of the assay was 6.6 ng/L. The proportion of PSA-API to tPSA (%PSA-API) tended to be lower in men with PCa (2.8%) than without cancer (3.3%) but was not statistically significant (P = 0.363). When used alone, %PSA-API [area under the curve (AUC) 0.546] did not improve detection of PCa, whereas %fPSA (AUC 0.710) and the sum of %fPSA and %PSA-API (AUC 0.723) did. At 90% diagnostic sensitivity, the diagnostic specificity for cancer was not significantly better for %fPSA + %PSA-API than for %fPSA alone (36% vs 30%).
Conclusions: Proximity ligation eliminated nonspecific background, enabling accurate measurement of PSA-API in serum specimens with moderately increased tPSA. The combined use of %PSA-API and %fPSA provided a modest improvement for PCa detection, but based on the current study cohort, it is uncertain whether the improvement has clinical utility. .
Syringyl-type simple plant phenolics as mediating oxidants in laccase catalyzed degradation of lignocellulosic materials: Model compound studies 10th EWLP, Stockholm, Sweden, August 25–28, 2008
Authors: Nousiainen Paula , Maijala Pekka , Hatakka Annele , Martínez Angel T. , Sipilä Jussi 
Published: July 2009

Abstract
The utility of simple syringyl-type phenolics of plant origin and some common synthetic compounds were compared with regard to their ability to act as laccase mediators in the oxidation of non-phenolic lignin model compounds. It was demonstrated that syringyl-type phenols, especially acetosyringone and methyl syringate, were able to mediate the oxidation of substrates of high oxidation potential by a laccase with a low redox potential. A mediator dose around 10% showed good performance compared to the equimolar quantities needed when the synthetic compounds 1-hydroxybenzotriazole or N-hydroxyacetanilide were used.
Titration of free phenolic groups in pulps 10th EWLP, Stockholm, Sweden, August 25–28, 2008
Authors: Delmas Delphine , Lachenal Dominique , Mortha Gérard , Marlin Nathalie , Calais Christophe 
Published: July 2009

Abstract
The ClO2 titration method for in situ measurement of free phenolic groups in pulp has been improved to minimize interferences from other groups susceptible to react with ClO2. The method is based upon the reaction between free phenolic groups and chlorine dioxide at a temperature of 0°C, in the presence of dimethyl sulfoxide. Theoretically, one free phenolic group consumes two molecules of ClO2. The pH of the ClO2 treatment was advantageously fixed at 6.7 using a phosphate buffer, and a new protocol was proposed to avoid any possible interference of quinone groups (either present in pulp or formed during the procedure) on the residual ClO2 titration step. The results obtained on isolated lignin samples were compared to those measured by 31P NMR spectroscopy. The ClO2 method gave substantially higher values, for reasons which deserve further investigation.
The influence of mannanase and endoglucanase treatment on the fibre stability of spruce CTMP
Authors: Strey Grethe , Wesley-Smith James , Wolfaardt Francois 
Published: July 2009

Abstract
An increase in moisture during printing can lead to movement of fibres, such as puffing (return of a fibre to its uncollapsed state), twisting, and lifting of fibres out of the paper web. Spruce fibres are especially subject to these movements, contributing to weak bonding and increased surface roughness. The aim of the present study was to treat spruce pulp with enzymes to improve fibre bonding and stability. Spruce chemi-thermo-mechanical pulp was prepared in the laboratory and treated with mannanase, endoglucanase, and with a combination of these enzymes. Strength properties were evaluated before and after wetting of handsheets and their transverse sections were examined by scanning electron microscopy. Handsheet properties before and after rewetting as well as measurement of lumen area of fibres proved to be effective in evaluating fibre movement and puffing. The treatment of pulp with mannanase or endoglucanase improved fibre stability; however, endoglucanase treatment resulted in a loss of strength. Mannanase appeared to modify the cell walls, making them more susceptible to beating and resulting in improved fibre development and inter-fibre bonding. Endoglucanase possibly damaged fibrils, and fibre degradation instead of fibre development occurred during beating. Stability of thin-walled fibres improved more than thick-walled fibres after enzyme treatment.
Study of the sorption-desorption properties of pine wood at the initial stage of decay by wood-rot fungi 10th EWLP, Stockholm, Sweden, August 25–28, 2008
Authors: Chirkova Jelena , Irbe Ilze , Andersone Ingeborga , Andersons Bruno 
Published: July 2009

Abstract
Hot water extraction of pine wood was carried out after 10 days of exposure to brown-rot fungi (Gloeophyllum trabeum, Coniophora puteana and Poria placenta) and a white-rot fungus (Coriolus versicolor). The microstructure of the wood cell wall was analysed by the water vapour sorption method. The content and composition of monosaccharides in the extracts were determined by high performance liquid chromatography. Despite the absence of essential mass losses at the initial stage of the contact with the fungi, slight changes in the cell wall microstructure can be observed, namely, the hydrophobisation and the change in the character of porosity in the region of 1–10 nm pore sizes. After hot water treatment, the mass decreases considerably, i.e., to 25% for the control and brown-rot treated samples and more than 30% for the white-rot treated sample. The sorption-desorption isotherms for the washed control sample and brown-rot samples were not changed practically, but the isotherm was changed clearly in the case of the white-rot treated sample. The microstructure of the white-rot sample changed after hot water washing radically and was accompanied with the formation of wide mesopores in the range of 5–9 nm width.
Chelating and antioxidant activity of lignans from Chilean woods (Cupressaceae)
Authors: Donoso-Fierro César , Becerra José , Bustos-Concha Evelyn , Silva Mario 
Published: July 2009

Abstract
Wood species resistant to biodegradation by fungi contain phenolic compounds with proven fungicidal activity. Saprophytic fungi are able to colonize wood and later begin to break down its polymeric components through metal-dependent reactions. These generate free radicals at the onset of the degradation process. Later on, extracellular enzymes are active that use metallic cofactors. Five lignans were isolated from the methanolic extracts of the Chilean heartwoods (Austrocedrus chilensis, Fitzroya cupressoides, and Pilgerodendron uviferum) belonging to the Cupressaceae: isotaxiresinol, secoisolariciresinol, isolariciresinol, didemethylmatairesinol, and matairesinol. Their structures were determined spectroscopically. The antioxidant activity of the methanolic extracts and the isolated compounds was determined in vitro against the radical 1,1-diphenyl-2-picrylhydrazyl (DPPH) and their iron-chelating capacity was evaluated by the Chrome Azurol S assay. All isolated methanolic extracts and lignans exhibited antioxidant activity against DPPH and Fe-chelating capacity with values greater than 87%. This may be interpreted that the antioxidant properties and metal-chelating capacity of these compounds have a protective effect on the wood of these species when exposed to attacks by saprophytic fungi.
Comparison of Corrosion Rate Measurement of Copper, Zinc, and C1018 Steel Using Electrochemical Frequency Modulation and Traditional Methods
Authors: Loveday David , Rodgers Robert 
Published: July 2009

Abstract
Experimental aspects of making corrosion rate measurements with the electrochemical frequency modulation technique (EFM) have been discussed. Corrosion rate and corrosion kinetic parameters can be obtained without prior knowledge of the Tafel slopes. Several cases were considered using a dummy cell designed to mimic a corrosion reaction. These approaches were then applied to copper, zinc, and carbon steel samples and the results were compared to more traditional electrochemical techniques like polarization resistance and electrochemical impedance spectroscopy. Good agreement has been observed between traditional methods and EFM.
Evaluation of Petroleum Products
Authors:   Sectional Committee Z11
Published: July 2009

Description
Exhaust valve performance and exhaust valve materials in gasoline engines have been recognized as a serious limitation to engine development since about 1910. There is good reason to believe that exhaust valve behavior was limiting engine performance even prior to 1910. With the best of current exhaust valve materials and designs, exhaust valve behavior is today only a minor limitation to engine performance and development. However, in some cases cost precludes the use of such materials or designs. Exhaust valves operate at elevated temperatures, usually in the range of about 1200 to 1400 F., but parts of the valve may in some cases reach 1600 F. and more. It is obvious that an exhaust valve material should possess, at operating temperature, a maximum of strength, of resistance to stretching, and of chemical inertness to oxygen and other constituents of the combustible charge prior to and after burning. Hardness of the material at operating temperature has recently been recognized as an additional desirable property, in order to avoid pounding, pitting, etc., of the portion of the valve which makes contact with the seat in the cylinder. A number of additional properties are now recognized as desirable or necessary attributes of an outstanding exhaust valve material, as will be pointed out later.
Correlations To Predict Frictional Pressure Loss of Hydraulic-Fracturing Slurry in Coiled Tubing
Authors: Shah Subhash , Zhou Yunxu , Bailey Michael , Hernandez John 
Published: July 2009

Summary
Compared with conventional-tubing fracturing, coiled-tubing (CT) fracturing has several advantages. CT fracturing has become an effective stimulation technique for multizone oil and gas wells. It is also an attractive production-enhancement method for multi-seam coalbed-methane wells, and wells with bypassed zones. The excessive frictional pressure loss through CT has been a concern in fracturing. The small diameter of the string limits the cross-sectional area open to flow. Furthermore, the tubing curvature causes secondary flow and results in extra flow resistance. This increased frictional pressure loss results in high surface pumping pressure. The maximum possible pump rate and sand concentration, therefore, have to be reduced. To design a CT fracturing job properly, it is essential to predict the frictional pressure loss through the tubing accurately.
This paper presents correlations for the prediction of frictional pressure loss of fracturing slurries in straight tubing and CT. They are developed on the basis of full-scale slurry-flow tests with 1½-in. CT and slurries prepared with 35 lbm/1,000 gal of guar gel. The extensive experiments were conducted at the full-scale CT-flow test facility. The proposed correlations have been verified with the experimental data and actual field CT-fracturing data. Case studies of wells recently fractured are provided to demonstrate the application of the correlations. The correlations will be useful to the CT engineers in their hydraulics design calculations.
A Procedure for Assessing the Value of Oilfield Sensors
Authors: Gilbert R. B. , Lake L. W. , Jablonowski C. J. , Jennings J. W. , Nunez E. J. 
Published: July 2009

Summary
Spurred by improvements in reliability, cost, and accuracy, sensors offer a means of increasing expected ultimate hydrocarbon recovery in producing assets as well as in planned and prospective projects. Ultimate hydrocarbon recoveries larger than those currently achieved are possible, especially when sensors are used with advanced recovery methods. However, it is often unclear if the incremental recovery justifies the cost of installing the sensors. This paper proposes a method for estimating incremental values attributable to real-time sensors and provides a demonstration of the method for several production technologies and reservoir settings. The method offers a transparent and practical means of making value of information (VOI) computations to be implemented readily by project teams. An additional benefit of this method is that the process of specifying the inputs to the analysis facilitates a systematic discussion of strengths and weaknesses, and builds consensus regarding assumptions. The method is applied to four scenarios developed by a panel of industry experts to represent generic, but yet realistic reservoirs. The results for these scenarios indicate the value of sensors depends on the market price for product and the type of reservoir and production technology. The greatest absolute economic value for the use of sensors is obtained for a deepwater reservoir, while the greatest economic value per equivalent barrel of oil produced is obtained for a mature onshore reservoir. These expected economic values are intended to be compared to the cost required to implement the sensors to assess whether or not there is an expected net benefit.
Innovative Use of Kaolinite in Downhole Scale Management: Squeeze-Life Enhancement and Water Shutoff
Authors: Fleming Niall , Ramstad Kari , Mathisen Anne-Mette , Nelson Alex , Kidd Sam 
Published: July 2009

Summary
Applied research has been undertaken to examine the potential of kaolinite combined with a kaolinite-fixation agent to increase squeeze lifetime through alteration of near-wellbore surface characteristics and mineralogy, and to provide water-shutoff control.
With respect to enhancing squeeze lifetime, it is documented that kaolinite increases the quantity of inhibitor adsorbed. Conversely, clean sandstone with low clay content commonly provides a poor substrate for adsorption. Furthermore, in reservoirs that experience near-wellbore formation damage because of kaolinite mobilization, it has been shown that the use of a fixation agent as part of a squeeze treatment can increase squeeze lifetime. Using these facts, research has assessed the feasibility of injecting micro-crystalline kaolinite (average particle size 2 μm) combined with the fixation agent and scale inhibitor as a means of mechanically altering near-wellbore mineralogy and surface-property characteristics within clean, high-permeability sandstones. The testing has been designed to mimic the squeeze procedure used in the field for performing such a job and involves no additional steps to those used in a normal squeeze (i.e., preflush, main treatment, overflush). The paper presents the results of coreflood experiments that demonstrate "proof of concept," along with examples of potential field applications.
A further concept, born from the initial idea, was the use of kaolinite and fixation agent for efficient, low-cost, environmentally friendly water shutoff. There are several available products for water shutoff, but the disadvantage of these is that they are not acceptable for use in Norway because of poor environmental characteristics. Hence, there was a need to fill this gap by developing water-shutoff technology to meet country-specific environmental legislation. The paper provides details of coreflood testing where an excess of kaolinite has been used to form an internal and external filter cake that is attached to the wellbore face and within the near-wellbore region using the fixation agent.
The paper draws on data from StatoilHydro-operated fields in order to highlight the potential of this innovative approach to downhole scale management and water control.
Coupled Adsorption/Precipitation of Scale Inhibitors: Experimental Results and Modeling
Authors: Kahrwad M. , Sorbie K. S. , Boak L. S. 
Published: July 2009

Summary
In this paper, results are presented on the general mechanisms by which scale inhibitors (SIs) are retained within porous media. There is a generally accepted view that the main two mechanisms of SI retention are "adsorption" and "precipitation," and these are described by different but related modeling approaches in the literature. These approaches have been used quite successfully to model field squeeze treatments. To analyze in a detailed and unambiguous manner where a given retention mechanism (e.g., pure adsorption) or mechanisms (e.g., coupled adsorption and precipitation) are operating requires that we carry out careful laboratory experiments under "field relevant" conditions.
In this work, we study adsorption vs. adsorption/precipitation by performing a series of experiments where we know that the system exhibits either (a) adsorption only or (b) coupled adsorption/precipitation. Experimentally, it is straightforward to determine which regime the system is in. We present the theory describing the coupled adsorption/precipitation process. In addition, an extensive series of experimental adsorption/precipitation measurements is presented for various mineral separates including sand, chlorite, siderite, muscovite, kaolinite, and feldspar. The coupled adsorption/precipitation model is in very good agreement with the experiment.