bluuebunny/crossref_metadata_2025 huggingface dataset:
Purification of Sea Pollution by a Bio-Micromachine
Authors: Nara Matsunori , Yoda Keiji
Published: February 2010

Contamination of sea water is proceeding quickly under the influence of climate changes including global warming. The cause of the expansion of seawater pollution is an elevated water temperature by the climate change and an inflow of the pollution river water. The problem of seawater pollution occurs as a result that planet’s environmental problem and regional environmental problems are combined. The effective method for removing these contaminants from sea water now is not developed. In this research, the method of producing the micromachine which fixed the photocatalyst to the surface of the substance designed so that it might float near a sea surface was built up. And experimental examination was performed about the conditions for removing the organic matter and nutritive salts in the sea using this micromachine. In addition, as a result of performing theoretical examination about a photocatalyst, the titanium dioxide was chosen as a suitable photocatalyst. In the examination about the quality of the material of a micromachine, since an organic polymer substance like styrene foam will be decomposed by the photocatalyst made to adhere to the surface, it decided to use the sphere of metal hollow. Metal took the corrosive protection performance into consideration. Moreover, the form of a metal ball was designed so that photocatalyst efficiency might become high. This metal ball can be collected and re-used after a treatment end. In order to make a photocatalyst bond to a surface of metal, baking by the water solvent method and an alcoholic solvent method was performed. Here, specific treatment conditions required in order to carry out the supported of the photocatalyst to metal certainly were clarified. A phosphate and nitrogen caused eutrophication and the damage by eutrophication is increasing them by in recent years. Then, the experiment about decomposition removal of the phosphate and nitrogen which are the causative agent which pollutes sea water was conducted. According to the evaluation experiment of the performance of a micromachine, the removal ratio of a phosphate was about 30%, and the removal ratio of nitrogen was about 60%. It was shown that the suitable amount of micro-machines per unit volume and the interval between them must be maintained here. As mentioned above, establishment of the manufacture method of a micromachine and the fundamental verification about the performance were able to be performed. However, a conclusion clear about the performance in the depth direction of a micromachine is not obtained, but it is a future subject.
Non-Linear Hysteretic Seabed Model for Catenary Pipeline Contact
Authors: Randolph Mark , Quiggin Peter
Published: February 2010

This paper presents a new mathematical model of the reaction force normal to the seabed, experienced by a pipeline or catenary riser in contact with the seabed. Such contact is currently often modeled using simple seabed contact models, and it is hoped that improved modeling of the seabed interaction will give more accurate predictions of system behavior, in particular for fatigue analysis. The model uses as its primary data the pipe diameter, the seabed soil shear strength profile with depth and the soil density. Additional parameters, in particular the maximum normalized stiffness of the pipe-soil response following reversal of motion, are used to derive non-linear hyperbolic functions that model the seabed resistance force as a function of the penetration. Different functions are used for the initial penetration, for uplift and for repenetration, and the function parameters are updated each time a penetration reversal occurs. This enables the model to capture the hysteretic behavior of the seabed response and the increasing penetration of the pipe under cycles of load in the vertical plane, although no attempt is made to model softening of the soil due to remolding. The paper documents the model equations and discusses their background and characteristics. The various non-dimensional parameters of the model that are used to control the resistance response are described and their effects are illustrated. The model is intended for use in practical engineering analysis and has been implemented in a commercial riser analysis program (Orcina 2008). The paper compares results obtained using the model against measured results for pipe-seabed interaction from laboratory and harbor experiments. It also presents results of using the model for engineering analysis of a riser under cyclic motions, and compares the resulting fatigue life with that obtained using a simple linear seabed model.
CFD Simulations of a Semi-Submersible With Absorbing Boundary Conditions
Authors: Wellens Peter R. , Luppes Roel , Veldman Arthur E. P. , Borsboom Mart J. A.
Published: February 2010

The CFD tool ComFLOW is suitable for simulations of two-phase flows in offshore applications. ComFLOW solves the Navier-Stokes equations in both water and (compressible) air. The water surface is advected through a Volume-of-Fluid method, with a height-function approach for improved accuracy. By employing Absorbing Boundary Conditions (ABC), boundaries can be located relatively close to an object, without influencing outgoing waves or generating numerical reflections that affect the waves inside the flow domain. Traditionally, boundaries are located far from the obstacle to avoid reflections; even when numerical damping zones are used. Hence, with the ABC approach less grid points are required for the same accuracy, which reduces the computing time considerably. Simulations of a semi-submersible model are compared to measurements. The overall agreement is reasonably good, for a wide range of wave conditions. The ABC performs well; numerical reflections are almost absent. Moreover, computing times reduce with a factor four compared to damping zone techniques.
Lock-In, Transient and Chaotic Response in Riser VIV
Authors: Chasparis Filippos , Modarres-Sadeghi Yahya , Hover Franz S. , Triantafyllou Michael S. , Tognarelli Michael , Beynet Pierre
Published: February 2010

We show using experimental data on a model riser that lock-in of long flexible risers placed in sheared or uniform cross-flows is a much richer phenomenon than lock-in of flexibly-mounted rigid cylinders under similar conditions. In particular, we find that the frequency content of the riser response may be either narrow-banded around a single dominant frequency (Type I response) or distributed along a relatively broad range of frequencies (Type II response). Distinct transition from Type I to Type II response, and vice versa, can occur several times within a single experimental record. Type I responses reveal features of a quasi-periodic oscillation, often accompanied by large 3rd harmonic components in the acceleration and strain signals, increased correlation length, stable riser trajectories, and monochromatic traveling or standing waves. Type II responses, on the other hand, are characterized by features of chaotic oscillation with small or negligible 3rd harmonic components in the acceleration and strain signals, reduced correlation length, and a continuous spectrum. We study how the fatigue damage differs in the two types of riser response.
Dynamic Analysis of Small Scale Floating Structure by Ship Wave Force
Authors: Eto Hiroaki , Yuasa Shigenori , Wada Kohei , Saijo Osamu , Ohki Kiyotaka
Published: February 2010

A floating structure has many options for effective ocean space utilization, for instance, the well known floating airport project, called Mega-Float. But after the end of the project, small scale floating structure began to be paid to attention. As the good example of such a kind of floating structure, there is the floating restaurant named “WATERLINE” (Figure 1) in Tokyo Bay. “WATERLINE” is small scale floating structure, and it is moored at the Tennoz Canal that is the closed water area. Therefore, when the ship passes around the floating restaurant, ship wave forces give a great influence on dynamic behavior of floating restaurant. As for ship waves, several studies have been made on the wave resistance and influence on ship handling concerning ship waves, but it is hardly to find papers focused on influence that ship wave forces give to dynamic behavior of small scale floating structure. In this research, dynamic behavior of small scale floating structure by ship wave forces was studied through both theoretical and experimental approach. As for the theoretical analysis, the equations of the Boussinesq type to treat shallow water area were adopted, and ADI (Alternating Direction Implicit) method in a numerical calculation was used for the analysis of these equations. And the floating structure was assumed to be a rigid body, and the displacement responses by ship wave forces were analyzed. With regard to experimental study, dynamic behavior of “WATERLINE” and wave height by the ship wave were actually measured. This measurement data is a profitable basic data for other researchers and engineers in order to analyze a floating structure. In the present paper, the validity of the numerical calculation program for ship wave response analysis was verified by the comparison between calculation results and the measurement results, the characteristics of the displacement response and the wave height were discussed by the numerical results that had been obtained by changing by the ship’s speed and the distance between floating structure and the ship. In addition, the evaluation of habitability in vertical motion of the small scale floating structure at the canal was examined by the diagram proposed from our research results [1], [2]. And, in regard to the ship that passes over around floating structure, ship’s speed limit and minimum distance between the ship and the floating structure were proposed.
Disconnectable Mooring System for Ice Class Floaters
Authors: Murray John , Gupta Apurva , Seng Foo Kok , Mortensen Asbjorn , Tung Wong Toh
Published: February 2010

Designs for offshore structures that will be deployed in arctic regions have to consider ice forces, which can be the governing design load. In shallow-water areas (< ∼100 m), fixed bottom caisson designs and artificial islands usually offer the best solutions. In deeper water, however, moored floating systems such as the ship-shaped Floating Production Unit (FPU), the Spar and the Single Column Floater (SCF™) are practical solutions. Even in shallower water where earthquakes are a threat, a moored floater can be a better option because of its ability to avoid seismic effects of the quake due to its suspension in the water above the sea floor. It is estimated that about 30% of the remaining oil and gas reserves lie in the arctic regions of the world. Special care has to be taken to design offshore platforms to survive these extreme arctic environments. Along with severe environmental conditions, there is a possibility of icebergs and multi-year ice sheets as well. A practical solution is to remove the floating structure in case of the expected loads on the structure exceed the maximum design loads. The platform can be brought back to location after the extreme environmental condition has passed. This paper describes a design for a disconnectable mooring system that comprises of external fairleads, submerged chain locker boxes and diverter units along with quick release mechanism and a single handling winch for each group of lines. The system works in tandem with the rig’s ROV and an anchor handling tugboat when connecting the system, while disconnection is automatic without any external assistance other than an emergency release signal. The paper provides the rationale for selecting this configuration based on its strength, redundancy requirements, quick disconnectable ability, without interfering with normal operation and presents a range of applications for this design.
Onshore and Offshore Transport Process Design for Carbon Dioxide Sequestration in a Marine Geological Structure
Authors: Huh Cheol , Kang Seong Gil , Hong Sup , Choi Jong Su , Moon Il Sung , Lee Chonn Ju , Cho Mang Ik , Baek Jong Hwa
Published: February 2010

In response to climate change, the Kyoto Protocol, and the need to reduce greenhouse gas emissions, researchers are looking to marine geological storage of CO2 as one of the most promising options. Marine geological storage of CO2 involves the capture of CO2 from major point sources (such as a power plant) and the transport of CO2 to storage sites in marine geological structures such as a deep sea saline aquifer. Since 2005, we have developed relevant technologies for marine geological storage of CO2. Those technologies include possible storage site surveys and basic designs for CO2 transport and storage processes. To design a reliable CO2 marine geological storage system, we devised a hypothetical scenario and used a numerical simulation tool to study its detailed processes. The process of transport CO2 from the capture sites to the storage sites can be simulated with a thermodynamic equation of state. We compared and analyzed the relevant equation of state, including the Benedict-Webb-Rubin-Starling (BWRS), Peng-Robinson (PR), Peng-Robinson-Boston-Mathias (PRBM) and Soave-Redlich-Kwong (SRK) equations of state. To evaluate the predictive accuracy of the equation of state, we compare the results of numerical calculations with experimental reference data. In a supercritical state (above 31.1°C and 73.9bar), which corresponds to the thermodynamic conditions of CO2 reservoir sites, the BWRS, PR, and PRBM equations of state showed a good predictive capability. On the other hand, the SRK equation of state showed a high error rate of 300% in the supercritical state. This paper analyzes the major design parameters that are useful for constructing onshore and offshore CO2 transport systems. On the basis of a parametric study of the hypothetical scenario, we suggest relevant variation ranges for the design parameters, particularly the flow rate, diameter, temperature, and pressure. Using the hypothetical scenario, we also studied how the thermodynamic conditions of CO2 affect on the fluid flow behavior and thermal characteristics of a pipeline transport system. In summary, this paper presents our analysis and deductions of the major design parameters that are useful for constructing onshore and offshore CO2 transport systems.
Numerical Analysis of Net Cage Dynamic Behavior Due to Concurrent Waves and Current
Authors: Suzuki Katsuya , Torisawa Shinsuke , Takagi Tsutomu
Published: February 2010

Large offshore net cages have been rather successful in reducing coastal contamination and developing aquacultural technology for raising large body-size species such as bluefin tuna. Deformation and shrinkage of net cages due to severe current and waves is one of the main causes of mortality of cultivated fish, and is thus of great concern for marine cage aquaculture. Even though the cage depth can be determined by pressure sensors at several locations on the cage, this is generally insufficient to measure the deformation and shrinkage. In this study, the dynamic shape and volume of a net cage under the influence of current and waves was analyzed using a numerical net geometry simulator previously validated by tank tests. The dynamic behavior of finite mass points distributed on the net cage under various wave and current conditions was simulated in detail, and reduction coefficients of the volume were calculated by the positions of these mass points on the cage. A drastic reduction of the cage volume occurred for a current velocity of 0.28–0.39 m/s. As the current velocity increased, the deepest point of the cage changed position, moving toward the downstream direction. The effective reduction of cage volume for a wave height of 3 m and a current velocity of 0.26 m/s was the same as that for a wave height of 5 m without any current. These results suggest that the volume deformation must be based on the actual measured depth of each part of the net cage, that the combination of wave levels and current velocities may have synergistic effects on the reduction of cage volume, and that our computational method is valid for estimating the volume reduction of a net cage under the influence of a concurrent wave and current field.
A New Improved Ocean Thermal Energy Conversion System With Suitable Floating Vessel Design
Authors: Srinivasan Nagan
Published: February 2010

Demand for energy worldwide is increasing significantly. A need for alternate energy sources has been brought to the attention of scientists and engineers. Ocean Thermal Energy Conversion (OTEC) is one among them which is in the development stage for the past three to four decades. Great amount of energy is available in deep-ocean with temperature difference between in upper surface-layer and in deep-ocean layer with maximum range of say up to 25 degree C in localized offshore locations near of equatorial waters. However, the technology is not in commercial operation due to the need of large capital cost. Advances in heat-exchanger material, cold-water pumps and working-fluid are the areas that research has been done extensively to make OTEC successful system. However none of that improvement in the design made OTEC technology attractive for cost effective commercialization. This paper proposes a new feasible OTEC system for about 100 MW power plants with significant change from the conventional system. The main purpose of the proposed new OTEC system is to reduce the capital cost significantly and make it commercial feasible. New types of floating vessels are proposed to support the new OTEC system to achieve cost efficiency. The floaters are very innovatively designed to support the new OTEC system. The new OTEC system with the corresponding floater significantly reduces the capital-cost of the OTEC system compared to the conventional OTEC system. Both the new OTEC system and the supporting floater system are presented herein.
Experimental Variation of Focusing Wave Groups for the Investigation of Their Predictability
Authors: Hennig Janou , Schmittner Christian E.
Published: February 2010

In deterministic model testing, focusing wave groups are used for the simulation of dedicated wave environments. They are characterized by the transient appearance of one relatively steep wave crest. The phasing of the wave components which leads to an exact focusing in one point in time and space is strongly dependent on the correct modeling of the wave phase velocity while the position of the focusing point depends on the wave group celerity. For wave generation purposes, the calculation of a wave maker control signal based on a target wave train at a desired position in the tank (inverse or backward modeling) is of crucial importance. Numerical wave tanks and empirical approaches are often calibrated based on wave characteristics measured in a particular tank. This paper presents model test results for the variation of frequency range, steepness and focal point of focusing wave groups at intermediate water depth. The measured characteristics are compared to predicted parameters.
Sensitivity of Slug Flow Mechanistic Models on Slug Length
Authors: Sarica Cem , Zhang Hong-Quan , Wilkens Robert J.
Published: February 2010

Slug flow is one of the common flow patterns in gas and oil production and transportation. One of the closure relationships required by the multiphase flow mechanistic models is slug length correlation. There are several closure relationships proposed in the literature as function of pipe geometry, pipe diameter and inclination angle, and to a lesser extent to the flow rates and fluid properties. In this paper, we show that most of the frequently used mechanistic models are insensitive to slug length information. The only exception to this is identified as the Zhang et al. Unified model [1]. The unified model shows sensitivity at high gas flow rates, while displaying a negligible sensitivity at low gas flow rates. In conclusion, the slug length closure relationship is not crucial for pressure loss and holdup calculations. It can be speculated that the success of the unit cell slug flow modeling approach could be attributed to insensitivity of the models to slug length considering the highly probabilistic nature of the slug length.
CAPWAP and Refined Wave Equation Analyses for Driveability Predictions and Capacity Assessment of Offshore Pile Installations
Authors: Rausche Frank , Nagy Matt , Webster Scott , Liang Liqun
Published: February 2010

Open ended pipe piles have to be driven in the offshore environment primarily as platform support piles or as conductor pipes. In either case, deep penetrations have to be achieved. In preparation of these potentially difficult installations, equipment selection and stress control is done by a predictive wave equation analysis. During pile driving, dynamic monitoring combined with CAPWAP signal matching analysis is a preferred method for bearing capacity assessment. After the fact, if dynamic measurements were not provided during pile driving, a wave equation analysis can again help perform a post-installation analysis for bearing capacity assessment, assuming a variety of parameters. Wave equation analyses require a variety of input parameters describing hammer and driving system performance and the pseudo-static and dynamic behavior of the soil. Measurements taken during the installation yield immediate results about hammer and pile performance. Soil resistance parameters can be extracted by careful signal matching analysis. Unfortunately, the measurement and associated analysis results cannot be used without further modification in the wave equation analysis, because the wave equation approach requires simplifications in hammer, driving system and soil models. Thus, a final step is the so-call Refined Wave Equation Analysis which combines all results obtained and produces a best possible match between measurements and analyses. This paper describes the process of the three analysis phases utilizing typical offshore pile installation records. The paper also gives guide lines for this analysis process as well as a summary of limitations. An important part of the paper includes recommendations for and discussion of the modeling of the soil resistance near the open ended pipe bottom. Finally, the paper discusses how the results should be used for greatest benefit of the deep foundation industry.
Economical Feasibility Study of Abandoned Oilfields Utilizing Smart Modeling Approach: Case Study
Authors: Belhaj Hadi , Zaman M. S. , Lay Terry
Published: February 2010

Petrel, Eclipse and Monte Carlo are three simulators often used separately to evaluate reservoir structure, production performance and economics/planning/risk analysis respectively. Integration of the three packages provides a very comprehensive and efficient assessment tool for oilfields or blocks with limited data by avoiding incompatibility, data transformation and interface problems. Many oil and gas fields that have been discovered in the past and abandoned as a high risk venture have become of prime interest to numerous smart investors taking advantage of high oil prices and advanced technology. Some of these discoveries have exhibited reasonable hydrocarbon accumulations through seismic surveys, actual drilling and initial well-testing. Their development has previously been hindered by uncertainty and by low oil prices. The ALT Field, North Africa, is a typical example. Only nine vertical wells were drilled in the ALT Field during the 1960’s including three dry holes. Low production from three zones of Chalk Carbonate formation with moderate porosity and very low permeability (less than 1 md), meant the field has been abandoned for over three decades. Recently, with oil prices flourishing, the field has caught the eye of many potential developers. By utilizing the three-simulator approach, the ALT field has been verified as a potential producer of commercial oil. Two scenarios, single-pool and two-pool, have been established for describing the field structure, both are economically feasible, with more profitability foreseen from the single-pool scenario. The two-pool scenario demonstrated the field contains 885MMblls OIIP with estimated total reserves of 310MMbbls of oil using waterflooding alone and an additional 89MMbbls using CO2 injection. The existing six vertical producers are recommended to be used for injection, while a pattern of horizontal wells are suggested to be drilled and used as producers. The horizontal wells are favored over vertical ones to overcome the very low permeability situation. Development of the ALT Field is ongoing based upon the findings of this study. The idea of the three-simulator approach has proven workable, thus has potential to be used in similar cases once minor technical software problems are resolved.
A Modular Differential Dielectric Sensor (DDS) for Use in Multiphase Separation, Process Measurement and Control—Part II: Experimental Investigation
Authors: Xiang D. , Mohan R. , Marrelli J. , Wang S. , Shoham O.
Published: February 2010

Accurate and continuous measurement of the percent water in crude oil production streams (watercut) over 0 to 100% range is critical for petroleum industry. High accuracy and stability are also required for surface measurement to support process control applications aimed at removing trace amounts of oil and particulates from produced water. This paper is a two-part paper — the first part [1] deals with analytical modeling of the Differential Dielectric Sensors (DDS) and the second part (current paper) discusses the results of key experimental investigations. A dedicated closed-loop experimental facility is used to obtain in-line real-time measurement of DD sensor data in a controlled configuration. A complete description of test facility is presented followed by detailed experimental results. The results show that DDS is unique in its use of very low noise and high sensitivity differential measurements between two identical sensors. In a process control system, DDS shows good measurement stability and is adaptive to composition measurements compensating for changes in oil composition, gas fraction, emulsion state, water NaCl concentration, temperature, and flow rate. Because of its auto calibration capability, DDS can also conduct real time calibration for sensor configuration changes caused by factors such as corrosion and erosion.
Hydrodynamic and Experimental Analysis on a Novel Hybrid Offshore Renewable Structure
Authors: Delpeche Kurt
Published: February 2010

Since the Kyoto Protocol in Japan in 1997, countries have been on a drive to reduce their carbon emissions but recently this drive has been given a new thrust. Security of energy supplies is now a high priority and one of the possible methods is by harnessing offshore renewable energy. It is proposed, that the use of a hybrid or a combination of two sources of renewable energy that utilizes a single floating structure can effectively reduce the cost of delivering renewable energy. Cost reduction is of key importance, however, it will not be the focus of this paper as it is a well proven concept. However, the motion characteristics of such a novel structure as the one that is presented here has never been fully examined and the literature is very limited on the subject. A scaled model of a conceptual structure was fabricated and subjected to regular waves for a range of wave heights and periods. The effect of wave-current interaction was noted and mooring line forces were measured. Conventional hydrodynamic analysis and rules used in ship structures and semi-submersible design were merged into one cohesive analysis and a comparison was made with the experimental results. There are two operational states that are mentioned, the ‘hybrid mode’ i.e. acting as a barge and a semisubmersible by virtue of the volume of the structure below the Mean Water Level (MWL). The second state is the ‘semisubmersible mode’, which has the pontoon and 75% column of the structure only below the MWL.
Apoptotic Cells Activate the “Phoenix Rising” Pathway to Promote Wound Healing and Tissue Regeneration
Authors: Li Fang , Huang Qian , Chen Jiang , Peng Yuanlin , Roop Dennis R. , Bedford Joel S. , Li Chuan-Yuan
Published: February 2010

Caspases in dying cells trigger the release of growth signals that promote tissue repair.
Pharmacokinetics of Cefotaxime and Desacetylcefotaxime in Infants during Extracorporeal Membrane Oxygenation
Authors: Ahsman Maurice J. , Wildschut Enno D. , Tibboel Dick , Mathot Ron A.
Published: February 2010

Extracorporeal membrane oxygenation (ECMO) is used to temporarily sustain cardiac and respiratory function in critically ill infants but can cause pharmacokinetic changes necessitating dose modifications. Cefotaxime (CTX) is used to prevent and treat infections during ECMO, but the current dose regimen is based on pharmacokinetic data obtained for non-ECMO patients. The objective of this study was to validate the standard dose regimen of 50 mg/kg of body weight twice a day (postnatal age [PNA], <1 week), 50 mg/kg three times a day (PNA, 1 to 4 weeks), or 37.5 mg/kg four times a day (PNA, >4 weeks). We included 37 neonates on ECMO, with a median (range) PNA of 3.3 (0.67 to 199) days and a median (range) body weight of 3.5 (2.0 to 6.2) kg at the onset of ECMO. Median (range) ECMO duration was 108 (16 to 374) h. Plasma samples were taken during routine care, and pharmacokinetic analysis of CTX and its active metabolite, desacetylcefotaxime (DACT), was done using nonlinear mixed-effects modeling (NONMEM). A one-compartment pharmacokinetic model for CTX and DACT adequately described the data. During ECMO, CTX clearance (CL
CTX
) was 0.36 liter/h (range, 0.19 to 0.75 liter/h), the volume of distribution of CTX (
V
CTX
) was 1.82 liters (0.73 to 3.02 liters), CL
DACT
was 1.46 liters/h (0.48 to 5.93 liters/h), and
V
DACT
was 11.0 liters (2.32 to 28.0 liters). Elimination half-lives for CTX and DACT were 3.5 h (1.6 to 6.8 h) and 5.4 h (0.8 to 14 h). Peak CTX concentration was 98.0 mg/liter (33.2 to 286 mg/liter). DACT concentration varied between 0 and 38.2 mg/liter, with a median of 10 mg/liter in the first 12 h postdose. Overall, CTX concentrations were above the MIC of 8 mg/liter over the entire dose interval. Only 1 of the 37 patients had a sub-MIC concentration for over 50% of the dose interval. In conclusion, the standard cefotaxime dose regimen provides sufficiently long periods of supra-MIC concentrations to provide adequate treatment of infants on ECMO.
Entry of
Neisseria meningitidis
into Mammalian Cells Requires the Src Family Protein Tyrosine Kinases
Authors: Slanina Heiko , König Alexandra , Hebling Sabrina , Hauck Christof R. , Frosch Matthias , Schubert-Unkmeir Alexandra
Published: February 2010

Neisseria meningitidis
, the causative agent of meningitis and septicemia, is able to attach to and invade a variety of cell types. In a previous study we showed that entry of
N. meningitidis
into human brain microvascular endothelial cells (HBMEC) is mediated by fibronectin bound to the outer membrane protein Opc, which forms a molecular bridge to α5β1-integrins. This interaction results in cytoskeletal remodeling and uptake of the bacteria. In this study we identified and characterized the intracellular signals involved in integrin-initiated uptake of
N. meningitidis
. We determined that the Src protein tyrosine kinases (PTKs) are activated in response to contact with
N. meningitidis
. Inhibition of Src PTK activity by the general tyrosine kinase inhibitor genistein and the specific Src inhibitor PP2 reduced Opc-mediated invasion of HBMEC and human embryonic kidney (HEK) 293T cells up to 90%. Moreover, overexpression of the cellular Src antagonist C-terminal Src kinase (CSK) also significantly reduced
N. meningitidis
invasion. Src PTK-deficient fibroblasts were impaired in the ability to internalize
N. meningitidis
and showed reduced phosphorylation of the cytoskeleton and decreased development of stress fibers. These data indicate that the Src family PTKs, particularly the Src protein, along with other proteins, are important signal proteins that are responsible for the transfer of signals from activated integrins to the cytoskeleton and thus mediate the endocytosis of
N. meningitidis
into brain endothelial cells.
Histophilus somniIbpA DR2/Fic in Virulence and Immunoprotection at the Natural Host Alveolar Epithelial Barrier
Authors: Zekarias Bereket , Mattoo Seema , Worby Carolyn , Lehmann Jason , Rosenbusch Ricardo F. , Corbeil Lynette B.
Published: February 2010

Newly recognized Fic family virulence proteins may be important in many bacterial pathogens. To relate cellular mechanisms to pathogenesis and immune protection, we studied the cytotoxicity of theHistophilus somniimmunoglobulin-binding protein A (IbpA) direct repeat 2 Fic domain (DR2/Fic) for natural host target cells. Live virulent IbpA-producingH. somnistrain 2336, a cell-free culture supernatant (CCS) of this strain, or recombinant DR2/Fic (rDR2/Fic) caused dramatic retraction and rounding of bovine alveolar type 2 (BAT2) epithelial cells. IbpA-deficientH. somnistrain 129Pt and a Fic motif His298Ala mutant rDR2/Fic protein were not cytotoxic. The cellular mechanism of DR2/Fic cytotoxicity was demonstrated by incubation of BAT2 cell lysates with strain 2336 CCS or rDR2/Fic in the presence of [α-32P]ATP, which resulted in adenylylation of Rho GTPases and cytoskeletal disruption. Since IbpA is not secreted by type III or type IV secretion systems, we determined whether DR2/Fic entered the host cytoplasm to access its Rho GTPase targets. AlthoughH. somnidid not invade BAT2 cells, DR2/Fic was internalized by cells treated withH. somni, CCS, or the rDR2/Fic protein, as shown by confocal immunomicroscopy. Transwell bacterial migration assays showed that large numbers of strain 2336 bacteria migrated between retracted BAT2 cells, but IbpA-deficient strain 129Pt did not cross a monolayer unless the monolayer was pretreated with strain 2336 CCS or rDR2/Fic protein. Antibody to rDR2/Fic or passively protective convalescent-phase serum blocked IbpA-mediated cytotoxicity and inhibitedH. somnitransmigration across BAT2 monolayers, confirming the role of DR2/Fic in pathogenesis and corresponding to the results forin vivoprotection in previous animal studies.
Using geographical information systems to assess the equitable distribution of traffic-calming measures: translational research
Authors: Rodgers Sarah E , Jones Sarah J , Macey Steven M , Lyons Ronan A
Published: February 2010

Objective

To assess whether traffic-calming features are equitably distributed in the UK.

Design

Cross-sectional database utilising geographical information system (GIS) and population data.

Setting

Four large regions in England and Wales, including areas in south Wales, south-west England, east Midlands and Surrey, for which map data were available.

Main outcome measures

The total proportion of road segments traffic calmed and the likelihood of road segments being traffic calmed by deprivation fifth.

Results

A total of 3.7% of road segments was traffic calmed on 95 791 km of road length. A higher proportion of traffic-calmed road segments was found in deprived areas when population density was taken into account. The odds of traffic calming in the most deprived areas, compared with the most affluent areas, was 2.83 (95% CI 2.815 to 2.835).

Conclusions

High resolution map data can be manipulated within a GIS to enable the distribution of traffic-calming measures to be assessed over large areas. There are very few traffic-calmed roads in any area and there is scope for more. Deprived areas have substantially more traffic calming. Making such data available to the public should be tested as an advocacy tool to increase the provision of traffic-calming features.
Development of ectomycorrhizae following inoculation of containerized Sitka and white spruce seedlings
Authors: Shaw III Charles G. , Molina Randy , Walden Judith
Published: February 2010

Containerized Sitka (Piceasitchensis (Bong.) Carr.) and white spruce (P. glauca (Moench) Voss) were inoculated at sowing with mycelial cultures of ectomycorrhizal fungi. The seedlings were grown in 66-cm3 cells for 6 months. Sitka spruce inoculated at Corvallis, OR, with Hebelomacrustuliniforme (Bull, ex St. Amans) Quél, Amanitamuscaria (L. ex Fr.) Pers. ex Hooker, or Laccarialaccata (Scop, ex Fr.) Berk and Br. had, respectively, 94, 92, and 99% of their short roots mycorrhizal. Seedlings colonized by A. muscaria were similar in size to uninoculated controls; those colonized by H. crustuliniforme or L. laccata were significantly smaller. Tricholomapessundatum (Fr.) Quél, sparsely colonized 10–25% of the Sitka spruce inoculated at Corvallis. At Petersburg, AK, 93% of the Sitka spruce inoculated with H. crustuliniforme were colonized with 69% of their short roots forming mycorrhizae. Colonized seedlings were similar in size to controls, except for a significantly greater (P < 0.05) shoot/root ratio and foliar concentrations of nitrogen and phosphorus. Sitka spruce colonized at Petersburg by Cenococcumgeophilum Fr. and maintained at the standard nursery fertilization rate had significantly fewer short roots mycorrhizal (23%) than seedlings maintained at half the standard fertilization rate (44%). White spruce were successfully colonized by C. geophilum and H. crustuliniforme. Pisolithustinctorius (Pers.) Coker and Couch failed to form mycorrhizae on either spruce.
Modèle de prédiction des essences feuillues et résineuses du Québec
Authors: Ung Chhun-Huor , Beaulieu Jean , Demers Daniel
Published: February 2010

This paper describes a prediction model adopted by the Department of Energy and Resources of Quebec to (i) update temporary sample plots and (ii) project into the future the state of permanent sample plots in Quebec forests. Predicting the growth of a forest species means predicting the state of this species in time. Three basic characteristics mark the state of a species in a given year: number of trees, their total basal area, and their total volume. To date, in Quebec, normal or empirical yield tables have been used to predict the state of some species in ideal or real growth conditions, but these yield tables apply only to pure or almost pure even-aged stands. The prediction model for hardwood and softwood species presented in this paper serves the same purpose as the yield tables; however, it differs from the yield tables in that it can predict the state of each hardwood or softwood species found in pure or mixed, even- or uneven-aged stands. The prediction model was validated for 19 species found in a pilot territory located in the Basse-Gatincau (southwestern Quebec). The paper terminates with a discussion on the limitation of the prediction model and the conditions for its use.
Effect of cluster sampling in biomass tables construction: linear regression models
Authors: Briggs E. F. , Cunia T.
Published: February 2010

To construct tree biomass tables it is customary to select the sample trees by cluster sampling and then to apply the classical least squares regression techniques under the assumption of simple random sampling. A modified linear regression procedure is proposed for which the assumption of simple random sampling is no longer required. The procedure can be used when (i) the regression of a biomass component on tree characteristics other than biomass can be approximated reasonably well by a linear function and (ii) the number of sample clusters is sufficiently large. Applied to two large cluster samples of trees, where the cluster size is approximately equal to five trees, and compared with the classical linear regression approach, the modified procedure results in biomass tables which arc essentially the same. The confidence intervals, however, are quite different. The classical least squares regression method results in intervals which, on the average, are about 60% as large as those calculated by the modified procedure.
Optimum allocation by dynamic programming for sampling on successive occasions with partial replacement of units
Authors: Omule Stephen A.Y. , Williams Douglas H.
Published: February 2010

The sequential nature of sampling on successive occasions with partial replacement of units (SPR) was exploited to cast the optimal SPR design problem as a multistage decision model which could be optimized through dynamic programming (DP). The objective of the design was to determine the number of remeasured and new sampling units at the successive occasions such that the cost of sampling was minimized and subject to the side conditions that the specified variance levels of the variables of interest were met. Using data published elsewhere, the DP approach was shown to give solutions almost identical to those obtained by other optimization techniques such as the graphical procedure. The advantage of the DP approach, however, was that it could handle optimization problems in which the sampling extended over several occasions.
Kraft pulping of white spruce bole and branch
Authors: Law K. N. , Koran Z.
Published: February 2010

When pulped by the same schedule, barked white spruce (Piceaglauca (Moench.) Voss.) branch wood was comparable in pulp yield to the bole wood. Handsheet made of unbeaten branch pulp showed higher bulk and stretch, comparable tensile and burst strengths, and considerably lower tear strength than bole wood. In the case of beaten pulps, branch pulp gave comparable tensile strength and stretch and lower burst and tear strengths. Inclusion of bark in the cooking increased chemical consumption and degraded sheet cleanliness. Pulping of mixtures containing up to 20% branch wood reduced the tear, burst, and tensile strengths by about 10%). It appeared that the inclusion of branch wood in the furnish within the natural amount limit in kraft pulping would be feasible.
Clonal variation in pollen-related characteristics of Douglas-fir
Authors: Adams W. T.
Published: February 2010

The mean number of pollen grains produced per pollen cone (P) ranged from 37 310 to 62 960 ([Formula: see text], SE = 1584) among eight seed-orchard clones of Douglas-fir (Pseudotsugamenziesii (Mirb.) Franco) and correlated significantly (r = 0.87, p < 0.05) with the mean number of microsporophylls per cone but not significantly with pollen cone length. The number of pollen grains per milligram (G) also differed among clones (range 2323–3112; [Formula: see text], SE = 32) and correlated significantly and negatively (r = −0.86) with grain diameter. Although this study provides evidence for genetic variation in both P and G, the differences were relatively small. Adjusting pollen-cone counts for P would add little, if any, precision to estimates of pollen production in seed-orchard clones. If balanced clonal representation in pollen mixes is desired, equal weights of pollen would probably suffice for most breeding applications.
Influence of type and amount of lignin on decay by Coriolusversicolor
Authors: Highley Terry L.
Published: February 2010

Samples of a hardwood containing primarily coniferous (guaiacyl) lignin and hardwoods and softwoods with normal amounts of guaiacyl and syringyl lignin were degraded by the white-rot fungus Coriolusversicolor (L. ex Fr.) to assess the influence of type and amount of lignin on rate of decay. Lignin and carbohydrate losses were compared for the woods at various degrees of weight loss. The hardwood with coniferous lignin was degraded in a manner similar to the softwoods, indicating that the type of lignin is more a factor in the slower rate of C. versicolor decay of softwoods than is the amount of lignin, or the anatomical structure itself.
Variation in frost injury to white ash families in an Ontario plantation
Authors: Clausen Knud E.
Published: February 2010

White ash (Fraxinusamericana L.) seedlings from 36 localities in the United States and Canada planted in Ontario were injured by both late spring and early fall frost. The percentage of trees injured by spring frost varied significantly among families but was poorly correlated with their geographic origin. In general, level of injury increased with latitude between latitudes 35 and 45° and then decreased at the higher latitudes. Environmental conditions in the plantation and family differences in leaf flushing probably contributed to the variation and possibly obscured any clear pattern in foliar injury. Dieback of the main stem due to fall frost, however, was closely related to latitude of seed origins and to the percent of trees that were still growing at the time of the first killing frost. White ash seedlings of local or northern origin are recommended for planting in this area because they are least susceptible to frost injury.
ON DOMINANCE RELATIONS IN DISJUNCTIVE SET-VALUED ORDERED INFORMATION SYSTEMS
Authors: QIAN Y. H. , LIANG J. Y. , SONG P. , DANG C. Y.
Published: February 2010

Set-valued information systems are generalized models of single-valued information systems. Its semantic interpretation can be classified into two categories: disjunctive and conjunctive. We focus on the former in this paper. By introducing four types of dominance relations to the disjunctive set-valued information systems, we establish a dominance-based rough sets approach, which is mainly based on the substitution of the indiscernibility relation by the dominance relations. Furthermore, we develop a new approach to sorting for objects in disjunctive set-valued ordered information systems, which is based on the dominance class of an object induced by a dominance relation. Finally, we propose criterion reductions of disjunctive set-valued ordered information systems that eliminate only those information that are not essential from the ordering of objects. The approaches show how to simplify a disjunctive set-valued ordered information system. Throughout this paper, we establish in detail the interrelationships among the four types of dominance relations, which include corresponding dominance classes, rough sets approaches, sorting for objects and criterion reductions. These results give a kind of feasible approaches to intelligent decision making in disjunctive set-valued ordered information systems.
Particle swarm optimizer with adaptive tabu and mutation
Authors: Wang Yu-Xuan , Xiang Qiao-Liang , Zhao Zhen-Dong
Published: February 2010

Evolutionary Algorithms (EAs) and Swarm Intelligence (SI) are widely used to tackle black-box global optimization problems when no prior knowledge is available. In order to increase search diversity and avoid stagnation in local optima, the mutation operator was introduced and has been extensively studied in EAs and SI-based algorithms. However, the performance after introducing mutation can be affected in many aspects and the parameters used to perform mutations are very hard to determine. For the purpose of developing efficient mutation operators, this article proposes a unified tabu and mutation framework with parameter adaptations in the context of the Particle Swarm Optimizer (PSO). The proposed framework is a significant extension of our preliminary work [Wang et al. 2007]. Empirical studies on 25 benchmark functions indicate that under the proposed framework: (1) excellent performance can be achieved even with a small number of mutations; (2) the derived algorithm consistently performs well on diverse types of problems and overall performance even surpasses the state-of-the-art PSO variants and representative mutation-based EAs; and (3) fast convergence rates can be preserved despite the use of a long jump mutation operator (the Cauchy mutation).