bluuebunny/crossref_metadata_2025 huggingface dataset:
Prediction of Environmental Pollutant Concentration
Authors: Baughman GL , Lassiter RR
Published: March 2009

An accurate estimate of the environmental concentration of a chemical substance resulting from its manufacture, use, and disposal is essential to any organized hazard assessment program. This estimate of dose can then be used in combination with results from laboratory-derived toxicity tests to assess the associated risks to aquatic species. In following this approach, one must consider what the environment does to the pollutant rather than the reverse. Chemical transformations of a pollutant can take many routes, several of the more significant being ionization as typified by simple acid-base equilibria, hydrolysis, photolysis, microbial degradation, volatilization, and partitioning (sorption). In general, first-order equations can be used to estimate each of these reaction rates using expressions that involve a term for the aqueous concentration and a function of some property of the environment such as pH, turbulence, or microbial population size. These major processes are identifiable, experimentally manageable, and can be arranged easily into differential equations expressing the net rate of change under given conditions. By specifying realistic ranges of these environmental properties, an analysis of pollutant changes can be carried out for a wide variety of aquatic environments. Such evaluative models of environmental processes as they affect pollutant behavior have been used to model successfully the aqueous concentration and fate of several pesticide formulations. This approach is useful since it incorporates the dynamics of no real environment but is based on the properties of stylized environments for which we can mathematically specify rather than measure inputs. This modeling approach can ultimately be improved as better understanding of its underlying concepts develops and as our knowledge of environmental processes improves.
Summary and Conclusions
Authors: Cairns J , Dickson KL , Maki AW
Published: March 2009

The primary workshop goal was to evaluate the “state of the art” in assessing the hazards of chemical substances to aquatic life. Following five days of discussion, the participants had not only accomplished this goal but had crystalized some basic concepts which represented significant contributions to the future development of hazard assessment procedures.
Prediction and Control of Macroscopic Fabrication Stresses in Hoop Wound, Fiberglass Rings
Authors: Reuter RC
Published: March 2009

Macroscopic, residual (bending) stresses in hoop wound, fiberglass rings are predicted by analytically modeling each phase of their fabrication. Layer “migration” is found to be the manufacturing phase which contributes most significantly to the inducement of bending stresses, once the stress profile has been established by the winding phase. Variation of winding tension through the thickness of the ring is shown to he an effective means of controlling these stresses. This control is demonstrated by presenting numerical and experimental results for rings wound with three winding tension variations.
Service Experience with H Grades of Austenitic Steel
Authors: Schnabel GJ
Published: March 2009

Premature creep-rupture swelling of AISI 321 austenitic stainless steel superheater tubes resulted in failures in the middle 1950s and promoted an extensive investigation. These failures in large utility boilers operating at pressures above 1500 psi and temperatures above 1000 F seriously challenged the economics and reliability of high pressure and high temperature. Failures were initially attributed to an extremely fine grain size occasioned by a low temperature solution heat treatment. Reheat treatment at higher temperatures to produce a coarser grain structure reduced the incidence of failure.

Subsequent results of a research project provided evidence that the final solution heat treatment and not the grain size was the most significant factor. Control of the carbon content was also found to be an important factor. A new grade called the “H” grade was introduced which incorporated specific heat treatments and control of carbon. This was applied to the 300 series steel in all product forms. Service experience has been successful with the H grades.

Recent investigations of Type 304 austenitic stainless steel indicate that a controlled nitrogen addition significantly enhanced the rupture life of this material, thereby increasing reliability. While the quest for higher temperature steam fossil units has been blunted with the advent of nuclear power, the fact still exists that higher pressures and temperatures result in significant increases in efficiency, and eventually will be pursued.
Microsampling Techniques for Infrared Spectroscopic Analysis of Lunar and Terrestrial Minerals
Authors: Estep PA , Kovach JJ , Karr C
Published: March 2009

Microsampling techniques have been developed for infrared analysis of single mineral grains (>150 μm) from lunar rocks and dusts, allowing a detailed molecular structure characterization of these complex fine-grained samples. The methods include special devices for isolating single grains, preparing micropellets from the grains, and obtaining in situ micro-specular reflectance spectra from grains in polished rock samples. Although specifically developed for the work on lunar samples, the special techniques for single grain infrared analysis were found to be equally useful in studies of complex terrestrial mineral samples. For example, infrared microanalysis has contributed substantially in solving problems concerned with our natural resources, such as the structural characterization of minerals from commercial iron ores, marine deposits, coal, and fly ash derived from coal.
Application of 14 MeV and Cf-252 Neutron Sources to Instrumental Neutron Activation Analysis of Lunar Samples
Authors: Janghorbani M , Gillum DE , Ehmann WD
Published: March 2009

Two neutron sources, a Cockroft-Walton 14 MeV neutron generator and a Cf-252 neutron source, have been applied to analyses of lunar samples for major and minor element determinations. Instrumentation and details of the techniques employed are discussed. It is shown that most major and minor elements found in lunar samples can be determined via the technique of instrumental neutron activation analysis employing these two relatively inexpensive neutron sources.
Some Measurements of Inhomogeneous Permanent Magnets by the Pole-Coil Method
Authors: Steingroever E
Published: March 2009

The pole-coil method for measuring demagnetization curves of permanent magnets is applied to inhomogeneous magnets. It allows the analysis of different causes of inhomogeneities: differences in the intrinsic magnetic properties within one test sample, in the degree of orientation of otherwise homogeneous material, in the effectiveness of magnetic heat and annealing treatment; inclusion of holes or nonmagnetic contaminations; unequal cross sections of the tested magnet, for example, with conical shape.

By the pole-coil method inhomogeneities can be recognized by differences in remanence and coercivity. But in the case of serial arrangement of different components the resulting coercivity of an inhomogeneous sample is an average value of the coercivities of the components and nearly unaffected by the location of the measuring spot. The measurement of a magnet with different cross-sectional areas on both faces yields data for immediate magnetic circuit design.
Corrosion Standards and Control in the Automobile Industry
Authors: Durbin CO
Published: March 2009

Motor vehicles, passenger cars, and trucks are used in many parts of the world. They are operated in all types of weather, parked outdoors when not in use, and thus, subjected to extremes of weather; high temperature, low temperature, rain, snow, high relative humidity, etc. They are driven over roads which have been salted for deicing or dust control purposes and parked in wet garages. Engine cooling systems, exhaust silencing and related parts, hydraulic brake mechanisms, and various lubrication systems are subjected to specific environments internally as well as the external environments noted above.
Corrosion Standards and Control in the Marine Industry
Authors: Brown BF
Published: March 2009

The operation of a ship involves many of the technologies required for the functioning of an urban society: generation of electric power; storage and preparation of food; dispensing of health services; furnishing heating, ventilation, and air conditioning; and in some instances operating nuclear power plants and aircraft. Thus, the corrosion control measures needed in the marine industry include many that have been developed for other industries unassociated with the marine environment. In addition, special measures are required because of the special corrosive nature of sea air and seawater. It is these specialized measures which form the subject of this chapter. (For example, corrosion control measures for steam generation are not discussed because the subject is included in the chapter on that technology.)
Corrosion Standards and Control in the Nuclear Power Industry
Authors: Berry WE
Published: March 2009

The first commercial nuclear fuel power plant in the United States was the Shippingport Atomic Power Station (PWR) that commenced operations late in 1957. Despite the brief existence of this industry, there have been a number of standards promulgated and adapted to meet the industry requirements. The need for standards in this field is emphasized by the high performance requirements and the necessity for overdesign to insure safety and prevent ecological damage.
Corrosion Standards and Control in the Chemical Industry
Authors: Gleekman LW
Published: March 2009

The chemical engineer in the chemical industry, responsible for the selection of materials of construction, currently must be more than a corrosion engineer; he must be in the broadest sense a materials engineer. In view of the fact that materials other than metals are widely used in the chemical industry, this engineer must know more than the metallurgy and electrochemistry of the destruction of metals (commonly called corrosion). He must know the technical and scientific information with regard to the deterioration of plastics, graphite, wood, rubber, concrete, roofing materials, coatings, glass, brick, mortars, among many materials.
Corrosion Standards and Control in the Nonferrous Metals Industry
Authors: Ailor WH
Published: March 2009

Nonferrous metals are used in a wide variety of applications: architectural and structural uses, as coatings for other metals or materials, as electrical conductors and protective anodes, as packaging foils, and in composite products. Corrosion testing, therefore, is diversified and includes laboratory, field, and service requirements in natural as well as artificial environments. Typical tests range from stress corrosion methods to durability of coatings and include effects of antifoulants, heat treatments, anodized coatings, and weldments. Weathering characteristics are important for not only corrosion considerations but also for reasons of esthetics.
Mechanisms of High-Temperature Fatigue
Authors: Gell M , Leverant GR
Published: March 2009

A review is presented of high-temperature fatigue mechanisms, with emphasis on nickel-base superalloys. It is shown that the slip character of a material (wavy versus planar), the extent of creep in the fatigue cycle, and the degree of oxidation all influence the mode and rate of fatigue crack initiation and propagation. These concepts are then used to explain the generally observed effects of temperature, mean stress, holdtime, and frequency on high-temperature fatigue life.
Derivation of a Failure Law for Creep Under a Cyclic Stress
Authors: Williams JA
Published: March 2009

The problem of creep fracture under an imposed cyclic stress is considered solely in terms of wedge crack growth. The derivation of a relationship similar to that suggested by Coffin for fatigue is illustrated, and this simple model is extended qualitatively to outline one form of a creep:fatigue interaction.
Fatigue of Supersonic Transport Materials Using Simulated Flight-by-Flight Loading
Authors: Imig LA
Published: March 2009

Methods to reduce the fatigue test time for structural materials which are candidates for supersonic transport airplanes were investigated by conducting real-time and accelerated fatigue tests. The tests employed sequences of stresses and temperatures to simulate the flights of a Mach 3 transport airplane. Some of the simulated flights were altered to determine the effect of the design mean stress and the number of stress cycles per flight on fatigue life. Salt solution was also applied in other tests. Notched Ti-8Al-1MO-1V and Ti-6Al-4V were used in the investigation.
Fatigue Crack Propagation in Steel Alloys at Elevated Temperatures
Authors: McHenry HI , Pense AW
Published: March 2009

The fatigue crack propagation characteristics of three steel alloys were evaluated at room and elevated temperatures in an air environment. The alloys and temperature ranges were: A212-B (σYS = 40 ksi) 75 to 800 F, A517-F (σYS = 104 ksi) 75 to 950 F, and 9Ni-4Co-0.30C (σYS = 185 ksi) 75 to 650 F. The compact tension specimen was used for the 9Ni-4Co-0.30C and A517-F tests. A modified compact tension specimen having deep face notches in the crack plane was used for the A212-B tests. Fracture mechanics parameters were used to evaluate the crack propagation data. When plotted as a function of the stress intensity range, ΔK, the crack growth rates increased with temperature in A517-F and A212-B; temperature did not influence the 9Ni-4Co-0.30C data. Tests at reduced cyclic frequencies were conducted on A517-F and 9Ni-4Co-0.30C steel. The crack growth rates increased as the frequency was reduced in A517-F at 500 and 950 F. In 9Ni-4Co-0.30C the growth rates at 500 and 650 F were essentially the same for cyclic frequencies of 10 and 0.002 Hz over the range of growth rates investigated.
Fatigue Crack Growth Characteristics of Several Austenitic Stainless Steels at High Temperature
Authors: Shahinian P , Smith HH , Watson HE
Published: March 2009

The resistance to fatigue crack growth of annealed stainless steels, Types 304, 316, 321, and 348, was determined at 77, 800, and 1100 F (25, 427, and 593 C). Crack growth rates were related to the stress intensity factor range (ΔK). With increase in temperature the rate of crack growth for a given (ΔK) increased. At room temperature the four steels had the same resistance to crack growth. However, at high temperatures crack growth became sensitive to the differences in composition and properties among the steels. At 1100 F (593 C), Type 348 steel had the greatest resistance to crack growth and Type 316 the lowest resistance. As a result, fatigue life was 3.4 times longer for Type 348 steel over Type 316 steel at this temperature. The characteristics of high-temperature fatigue crack growth were examined.
Effect of Mean Stress on the High-Cycle Fatigue Behavior of Udimet 710 at 1000 F
Authors: Moon DM , Sabol GP
Published: March 2009

The effect of mean stress on the high-cycle fatigue behavior of a wrought nickel-base superalloy, Udimet 710, was studied in air at 1000 F. Under the conditions of testing, which varied from a ratio of the alternating to mean stress, A, of 0.25 to ∞, the endurance limit was almost independent of mean stress. At all values of mean stress, the alloy deformed by superlattice dislocation pairs, shearing both the gamma and gamma-prime phases, resulting in dense planar bands of dislocations. The number of planar bands of dislocations, however, was found to decrease with decreasing mean stress. Independent of the mean stress, fatigue crack initiation took place along the dense bands of dislocations by slip plane decohesion.

Once initiated, the fatigue crack continued to propagate for one or two grain diameters in a Stage I mode before changing to a Stage II mode of propagation. The amount of the remaining fracture surface covered by Stage II crack growth prior to overload decreased with increasing mean stress. However, in the Stage II region of crack growth, the striation spacing, 0.5 µm, was found to be independent of mean stress.

The independence of the fatigue strength on mean stress was concluded to result from the interaction of two competing factors. As the mean stress is increased, the time spent in crack propagation is decreased due to the fact that the Stage I crack growth rate is accelerated, and less Stage II crack growth is required to exceed the fracture strength of the remaining specimen. In addition, at the higher mean stresses, the increased slip dispersal resulted in a greater amount of time being required to build up the dislocation density within a deformation band to the density required for decohesion. The independence of the endurance limit on mean stress, therefore, is related to the shorter time spent in crack propagation at the high mean stress being compensated for by the longer time spent in initiating a crack due to the dispersal of slip onto a greater number of slip planes.
Low-Cycle Fatigue with Combined Thermal and Strain Cycling
Authors: Lindholm US , Davidson DL
Published: March 2009

Test data are reported for both isothermal and nonisothermal strain cycling of a nickel-base superalloy in the temperature range from 1100 to 1700 F. The mechanical strain range for all tests was held constant while the mean strain, holdtime, and thermal cycling was varied. The results are discussed in terms of energy criterion for fatigue life.
Ratchetting Under Cyclic Axial Strain with Torsional Stress
Authors: Yamanouchi H , Asada Y , Wakamatsu Y
Published: March 2009

In order to investigate the fundamental behavior of thermal stress ratchetting, strain controlled push-pull low-cycle fatigue tests with steady torsional stress were conducted on ASTM A302-B steel, AISI 304 steel, and JIS SCM 3 steel under constant elevated and cyclic temperatures. The test results are summarized as follows: (1) Torsional ratchet deformation gradually increased as a permanent deformation fluctuating as axial strain changed. The amplitude of the fluctuation depends on cyclic axial strain, but permanent deformation depends on steady stress as well as cyclic axial strain. (2) Ratchet strain increased at a nearly constant rate for each cycle of axial strain. The rate of increase is proportional to steady torsional stress and exponentially proportional to the axial strain amplitude. (3) The torsional stress and deformation caused by the tests do not influence low cycle fatigue or thermal-fatigue strength.
Kinetic Deformation Criteria of Cyclic Fracture at High Temperature
Authors: Serensen SV , Schneiderovitch RM , Gusenkov AP
Published: March 2009

A strain range partitioning method for the analysis of failure by the interaction of creep and fatigue is proposed. A conception is made of the onesided deformation (mean strain) to account for part of the creep damage; the time (and temperature) dependent behavior of the strain to failure is used to modify the common low-temperature low-cycle fatigue equations. Data from 18Cr, 8Ni stainless steel are used as a basis for demonstrating the method. A conventional linear damage summation technique is used for comparison with the results of the proposed method.
Elevated Temperature Test of Welded Furnace Wall Sections
Authors: Lawton CW , Bynum JE
Published: March 2009

Welded furnace walls of a modern utility steam generator are subjected to a cyclic system of complex stresses from thermal gradients and mechanical loads as the generator responds to the power load demand. In the fatigue evaluation of the walls, the designer needs a design curve which relates and incorporates the broad spectrum of production tolerances (geometry and material) to the basic material fatigue properties at the elevated temperatures experienced by the steam generator. A research program has been conducted to evaluate the fatigue behavior of a composite (combined wrought and welded structure) furnace wall section.

The fatigue capabilities of the welded furnace wall construction were established experimentally using production specimens of the wall. The specimens were subjected to deflection-controlled alternating flexure tests. The test series were run at 1050 F and included both continuous cycling and holdtimes applied at both extremes of the deflection cycle and at one extreme of the deflection cycle.
Skid Resistance of Pavements
Authors: Rizenbergs RL , Burchett JL , Napier CT
Published: March 2009

Standard pavement types and experimental surfaces on roads throughout Kentucky were evaluated in terms of skid resistance and effects of traffic, wear, and polishing. Friction-versus-speed gradients and the relationships between locked-wheel and incipient friction were determined. Asphaltic concrete pavements on high-speed, four-lane roads were found to be significantly more skid resistant than on two-lane highways and somewhat more skid resistant than concrete surfaces (especially those containing calcareous gravel aggregates). Sand-asphalt surfaces containing significant proportions of limestone sands showed inadequate level of friction for the traffic sustained. Several experimental sand asphalts without limestone sands exhibited greater skid resistance; Kentucky rock asphalt surfaces remain the most skid resistant of all surfaces investigated.
Skid Resistance of Highway Pavements
Authors: Wilcox RG
Published: March 2009

Description

Nine papers explore in depth the analysis of slipperiness of various types of pavements, the analysis of skid resistance and relationship to tires. Of interest to auto designers, tire technologists, and pavement designers.
Sampling, Standards and Homogeneity
Authors: Kennedy WR , Woodruff JF
Published: March 2009

Description

Eleven papers treat the problems of sampling, homogeneity and standard reference materials and how they affect the analyst.
Building Seals and Sealants
Authors: Panek J
Published: March 2009

Description

The Book Committee of ASTM Committee C24 on Building Joint Sealants deeply appreciates the efforts of the many contributors who wrote papers and gave their time and effort to make this book a relatively complete treatise on the subject, and thanks them for their assistance. The authors of the papers have been allowed wide latitude in expressing their views, opinions, and details related to their subject matter.
Suicidal Behavior in the Western Pacific Region: Characteristics and Trends
Authors: De Leo Diego , Milner Allison , Xiangdong Wang
Published: March 2009

Current knowledge of suicidal behavior in the Western Pacific region is relatively limited when compared to other areas of the world. This area is characterized by a wide diversity of social, economic, and cultural aspects that do not permit any homogenous reading of suicide phenomena. Data from countries of the region included in this article suggest the existence of important differences among nations in terms of gender, age, and methods of suicide, as well role of mental illness. In addition, the Western Pacific region appears to be affected by higher rates of suicide than other areas in the world, with signs of progressive worsening in recent years and worrying predictions for the next two decades. The Suicide Trends in At‐Risk Territories (START) Study, initiated by the World Health Organization Regional Office in Manila, seeks to research the incidence of both fatal and nonfatal suicidal behavior in countries of the region and to implement interventions for suicide attempters. This ambitious project is expected to standardize data collection procedures and improve the knowledge cultural factors in suicide.
Swimming exercise at weaning improves glycemic control and inhibits the onset of monosodium l-glutamate-obesity in mice
Authors: Andreazzi A E , Scomparin D X , Mesquita F P , Balbo S L , Gravena C , De Oliveira J C , Rinaldi W , Garcia R M G , Grassiolli S , Mathias P C F
Published: March 2009

Swimming exercises by weaning pups inhibited hypothalamic obesity onset and recovered sympathoadrenal axis activity, but this was not observed when exercise training was applied to young adult mice. However, the mechanisms producing this improved metabolism are still not fully understood. Low-intensity swimming training started at an early age and was undertaken to observe glycemic control in hypothalamic–obese mice produced by neonatal treatment with monosodium l-glutamate (MSG). Whereas MSG and control mice swam for 15 min/day, 3 days a week, from the weaning stage up to 90 days old, sedentary MSG and normal mice did not exercise at all. After 14 h of fasting, animals were killed at 90 days of age. Perigonadal fat accumulation was measured to estimate obesity. Fasting blood glucose and insulin concentrations were also measured. Fresh isolated pancreatic islets were used to test glucose-induced insulin release and total catecholamine from the adrenal glands was measured. Mice were also submitted to intraperitoneal glucose tolerance test. MSG-obese mice showed fasting hyperglycemia, hyperinsulinemia, and glucose intolerance. Severe reduction of adrenal catecholamines content has also been reported. Besides, the inhibition of fat tissue accretion, exercise caused normalization of insulin blood levels and glycemic control. The pancreatic islets of obese mice, with impaired glucose-induced insulin secretion, were recovered after swimming exercises. Adrenal catecholamine content was increased by swimming. Results show that attenuation of MSG-hypothalamic obesity onset is caused, at least in part, by modulation of sympathoadrenal axis activity imposed by early exercise, which may be associated with subsequent glucose metabolism improvement.
Energy from earth-coupled structures, foundations, tunnels and sewers
Authors: Adam D. , Markiewicz R.
Published: March 2009

Ground-embedded structures such as shallow foundations, bored piles, diaphragm walls, tunnel cut-and-cover walls, tunnel linings, anchors for NATM tunnelling and even sewer systems can be used as absorber elements for ground heat exchange. The technology is based on absorber pipes installed within concrete elements and a heat carrier fluid circulated through the system; heat is extracted from the ground or stored in the ground for heating and cooling of associated buildings. This promising technology leads to a reduction of fossil energy consumption at moderate installation and low operation costs. This paper describes some of the varied applications of the technology in Austria, ranging from the high-rise building Uniqa Tower in the city of Vienna to the Vienna metro extension U2 and, most recently, at the new 15 km long Lainzer tunnel at construction lots LT44 and LT32.
Early Stress Response: A Vulnerability Framework for Functional Impairment Following Mild Traumatic Brain Injury
Authors: Bay Esther H. , Liberzon Israel
Published: March 2009

Nearly 64% of people with mild traumatic brain injury (MTBI) experience prolonged symptoms and functional impairments lasting months or years postinjury. Explanations for delayed recovery have varied and lacked a guiding framework, hindering intervention science. Using theory substruction and adapting McLean and associates’ biopsychosocial model for chronic pain after trauma, we suggest that perceived psychological stress and associated neurobiological responses may predict risk for functional impairment. This model can be tested using a biopsychosocial approach to determine the interplay of psychological stress and neurobiological responses implicated in functional impairments after MTBI. Testing of this model will advance understanding of pathways to postconcussion syndrome.
Multigenerational Timeline and Understanding of Diabetes and Self-Care
Authors: Scollan-Koliopoulos Melissa , Walker Elizabeth A.
Published: March 2009

Testing the practice–theory multigenerational legacies of diabetes, effects of a family member’s perceptions of the time line and understanding of diabetes on participants’ perceptions of their own diabetes and effect of their own perceptions on self-care were examined. Using a cross-sectional descriptive design, 123 participants completed study instruments by mail. Memories of a family member’s perception of the time line (r = .25, p = .01 ) and understanding of diabetes (r = .32, p = .01) were related; participants’ own perceptions of time line (β = –.24) and understanding (β = .10) accounted for significant variance in dietary adherence, with time line contributing unique variance (R2 = .06, F = 3.3, p = .04). The perceptions were not associated with other self-care behaviors. Findings illuminate effects of time line and understanding of diabetes in patients with family history of diabetes.
Analysis of Magnetic Resonance Images of Disk Positions and Deformities in 1,265 Patients with Temporomandibular Disorder
Authors: Choi Yong-Suk , Asaumi Jun-ichi , Hisatomi Miki , Unetsubo Teruhisa , Yanagi Yoshinobu , Matsuzaki Hidenobu , Konouchi Hironobu , Hwang Eui-Hwan , Lee Sang-Rae
Published: March 2009

Objectives

To compare MRI manifestations according to gender and age and to identify correlations between clinical manifestations and MRI findings in patients with temporomandibular disorder (TMD) as based on a large series.

Materials and Methods

Fat suppressed oblique sagittal images of the open and closed mouth were acquired, and MRI scanning parameters were applied.

Results

The patients consisted of 946 females (average, 36.6 years old), and 319 males (average, 34.3 years old). In all TMD patients, 945 had symptoms in the unilateral temporomandibular joint (TMJ) and 320 in the bilateral TMJ. There were significant differences in the distribution of disk positions based on age, regardless of gender, in the unilaterally and bilaterally symptomatic groups; however, the results were not significant in the asymptomatic group. There were significant differences with respect to the distribution of disk positions between males and females in asymptomatic group and in the unilaterally symptomatic group, although the bilaterally symptomatic group did not show significant differences in this regard. As regards the disk positions in the joints of the three groups (asymptomatic group, unilaterally and bilaterally symptomatic groups), there were significant interactive effects of disk positions, regardless of gender. There were statistically significant age-related differences in disk deformities in all symptom groups, regardless of gender, except for in the group of males lacking symptoms in either joint. As regards disk deformities among the three groups studies here, there were significant interactive effects for disk positions, regardless of gender.
Show Me The Money
Authors: Edlin Aaron S. , Jaffee Dwight M.
Published: March 2009

Aaron Edlin and Dwight Jaffee wonder: where has all the money and credit gone? Bank reserves at the Fed are monumental, and they suggest a tax on excess reserves.
Zinc Project: Subsea Maintenance and Remedial Action Approach for the Subsea Control System
Authors: Stair M.A. , Clark G.A. , Schmidt R.J.
Published: March 2009

Zinc is a 10 slot subsea production template and manifold installed in awater depth of 1460 feet in the Exxon Mississippi Canyon Block 354 Field in theGulf of Mexico. Zinc, which is located approximately 50 miles south of GrandIsle, produces through three flowlines to the Exxon Alabaster Platform locatedin Mississippi Block 397 approximately 6 miles to the west of Zinc. AnElectrohydraulic Multiplexed Control System provides for control and monitoringof the Zinc subsea and platform equipment.

This paper describes Exxon's maintenance and remedial action approach forthe Zinc Subsea Control System. A companion overview paper describes theequipment resulting from this approach.

Introduction

Subsea equipment reliability/availability is a critical factor in keepingsubsea wells on production, and thus in maximizing a subsea project's economicreturn. Equipment availability is dictated by the combination of (a) theequipment's inherent reliability, (b) the levels of redundancy provided, (c)the capability to perform routine equipment inspection, performance evaluation, and maintenance, and (d) the timeliness that repairs can be effected whenrequired. The challenge for the Zinc Project Team in providing for maintenanceand repair capabilities was to achieve a proper balance of these factors, thusbalancing the project's initial investment and operating costs.

Zinc has a planned production life of 20 years. To be assured of achievingthis production life, considerable maintenance capabilities have beenincorporated into the Zinc equipment. The most extreme of these capabilities isretrieval and reinstallation of the Zinc Subsea Production Manifold, whichcontains all manifold piping and valves, the Subsea Control System equipment, and the hydraulic distribution network. This is done independently of theSubsea Template; however, to do so will require that all wells be killed andsuitably plugged and the X-mas Trees removed.

Retrieving and reinstalling the Subsea Manifold for repair will be verycostly and not without risk to the wells and equipment. To minimize the chancesof having to undertake this operation due to control system failure, the ZincElectrohydraulic Multiplex Subsea Control System equipment has incorporatedsubstantial redundancy and maintenance provisions as the clearly preferredmeans of repair.
Recent Developments in the Towing of Very Long Pipeline Bundles Using the CDTM Method
Authors: Dercksen Albertus , Taconis Taco
Published: March 2009

Fully integrated pipeline bundles are built and tested onshore. The bundlesare towed to the field using the Controlled Depth Towing Method (CDTM). Recently this method was used to tow a very long bundle (6.7 km) to the Piperfield in the British sector of the North Sea.

Time domain simulations were carried out to predict the bundle behaviour indifferent situations. A discussion of the numerical model will be presented. Several parts of the bundle configuration were model tested and full scalemonitoring was performed during the tow at sea. Bundle tow in still water andsurvival sea states is discussed as well as the impacts of failure modes on thebundle behaviour.

Introduction

Fully integrated pipeline bundles are built and tested at the productionsite. After completion the bundle is launched and towed to the field. Often itwill be necessary to cross other pipelines located on the tow route from theproduction site.

To achieve clearance with these other pipelines it is essential to perform asafe tow. To this extent a dynamic analysis of the tow is carried out.

The importance of having reliable numerical methods to predict the dynamicbehaviour of towed pipeline bundles is given by the fact that it is extremelydifficult to carry out model tests on these systems due to their immenselengths.

The numerical model presented in this paper is based on a lumped massapproach, allowing flexibility with respect to modelling of differentconfigurations. Model tests were carried out to gather information aboutessential items of the tow. Full scale monitoring was carried out to validatethe numerical model for future projects.

In principle CDTM involves the transportation of a pipeline bundle suspendedbetween two tugs, the Leading Tug (LT) and the Trailing Tug (TT), Figure 1. Tomaintain control during tow, the bundle is designed and constructed withinspecific tolerances with respect to its submerged weight.
Transcriptional Modulation of the Immune Response by Peroxisome Proliferator-Activated Receptor-α Agonists in Autoimmune Disease
Authors: Gocke Anne R. , Hussain Rehana Z. , Yang Yuhong , Peng Haiyan , Weiner Jeffrey , Ben Li-Hong , Drew Paul D. , Stuve Olaf , Lovett-Racke Amy E. , Racke Michael K.
Published: March 2009

Peroxisome proliferator-activated receptor-α (PPARα) agonists have been shown to have a therapeutic benefit in experimental autoimmune encephalomyelitis (EAE), an animal model for multiple sclerosis (MS). In this study, we investigated the mechanism by which the PPARα agonist gemfibrozil induces immune deviation and protects mice from EAE. We demonstrated that treatment with gemfibrozil increases expression of the Th2 transcription factor GATA-3 and decreases expression of the Th1 transcription factor T-bet in vitro and directly ex vivo. These changes correlated with an increase in nuclear PPARα expression. Moreover, the protective effects of PPARα agonists in EAE were shown to be partially dependent on IL-4 and to occur in a receptor-dependent manner. PPARα was demonstrated, for the first time, to regulate the IL-4 and IL-5 genes and to bind the IL-4 promoter in the presence of steroid receptor coactivator-1, indicating that PPARα can directly transactivate the IL-4 gene. Finally, therapeutic administration of PPARα agonists ameliorated clinically established EAE, suggesting that PPARα agonists may provide a treatment option for immune-mediated inflammatory diseases.
Functional Killer Ig-Like Receptors on Human Memory CD4+ T Cells Specific for Cytomegalovirus
Authors: van Bergen Jeroen , Kooy-Winkelaar Engelina M. C. , van Dongen Henrike , van Gaalen Floris A. , Thompson Allan , Huizinga Tom W. J. , Feltkamp Mariet C. W. , Toes René E. M. , Koning Frits
Published: March 2009

Although very few CD4+ T cells express killer Ig receptors (KIR), a large proportion of CD4+ T cells with a late memory phenotype, characterized by the absence of CD28, does express KIR. Here, we show that KIR expression on CD4+ T cells is also associated with memory T cell function, by showing that the frequency of CMV-specific cells is higher in CD4+KIR+ than CD4+KIR− T cells. In addition, engagement of an inhibitory KIR inhibited the CMV-specific proliferation of these CD4+KIR+ memory T cells, but had no detectable effect on cytokine production. Our data reveal that, in marked contrast with CD8+ T cells, the activity of a subset of CMV-specific CD4+ T cells is modulated by HLA class I-specific KIR. Thus, the CMV-induced down-regulation of HLA class I may in fact enhance memory CMV-specific CD4+ T cell responses restricted by HLA class II.
TLR2/MyD88-Dependent and -Independent Activation of Mast Cell IgE Responses by the Skin Commensal Yeast Malassezia sympodialis
Authors: Selander Christine , Engblom Camilla , Nilsson Gunnar , Scheynius Annika , Andersson Carolina Lunderius
Published: March 2009

Atopic eczema (AE) is a chronic inflammatory skin disease. Approximately 50% of adult AE patients have allergen-specific IgE reactivity to the skin commensal yeast Malassezia spp. Due to the ruptured skin barrier in AE, it is likely that Malassezia can come into contact with mast cells, which are known to be involved in AE. We therefore hypothesized that Malassezia spp. can activate mast cells. Bone marrow-derived mast cells (BMMCs) were generated from wild type, TLR2, TLR4, and MyD88 gene-deleted mice and cocultured with Malassezia sympodialis extract. We recorded that M. sympodialis induced release of cysteinyl leukotrienes in a dose-dependent manner in nonsensitized and IgE-anti-trinitrophenyl-sensitized BMMCs, respectively, with three times higher levels in the latter type of cells. IgE-sensitized BMMCs also responded by degranulation as assessed by release of β-hexosaminidase, increased MCP-1 production through a MyD88-independent pathway, and activated phosphorylation of the MAPK ERK1/2. Furthermore, M. sympodialis enhanced the degranulation of IgE receptor cross-linked wild-type BMMCs and altered the IL-6 release dose-dependently. This degranulation was independent of TLR2, TLR4, and MyD88, whereas the IL-6 production was dependent on the TLR2/MyD88 pathway and MAPK signaling. In conclusion, M. sympodialis extract can activate nonsensitized and IgE-sensitized mast cells to release inflammatory mediators, to enhance the IgE-mediated degranulation of mast cells, and to modulate MAPK activation and by signaling through the TLR2/MyD88 pathway to modify the IL-6 production of IgE receptor cross-linked mast cells. Collectively, these findings indicate that M. sympodialis can activate mast cells and might thus exacerbate the inflammatory response in AE.
Autophagy Is Essential for Mitochondrial Clearance in Mature T Lymphocytes
Authors: Pua Heather H. , Guo Jian , Komatsu Masaaki , He You-Wen
Published: March 2009

Macroautophagy plays an important role in the regulation of cell survival, metabolism, and the lysosomal degradation of cytoplasmic material. In the immune system, autophagy contributes to the clearance of intracellular pathogens, MHCII cross-presentation of endogenous Ags, as well as cell survival. We and others have demonstrated that autophagy occurs in T lymphocytes and contributes to the regulation of their cellular function, including survival and proliferation. Here we show that the essential autophagy gene Atg7 is required in a cell-intrinsic manner for the survival of mature primary T lymphocytes. We also find that mitochondrial content is developmentally regulated in T but not in B cells, with exit from the thymus marking a transition from high mitochondrial content in thymocytes to lower mitochondrial content in mature T cells. Macroautophagy has been proposed to play an important role in the clearance of intracellular organelles, and autophagy-deficient mature T cells fail to reduce their mitochondrial content in vivo. Consistent with alterations in mitochondrial content, autophagy-deficient T cells have increased reactive oxygen species production as well as an imbalance in pro- and antiapoptotic protein expression. With much recent interest in the possibility of autophagy-dependent developmentally programmed clearance of organelles in lens epithelial cells and erythrocytes, our data demonstrate that autophagy may have a physiologically significant role in the clearance of superfluous mitochondria in T lymphocytes as part of normal T cell homeostasis.
CD4-Positive T Lymphocytes Provide a Neuroimmunological Link in the Control of Adult Hippocampal Neurogenesis
Authors: Wolf Susanne A. , Steiner Barbara , Akpinarli Akgul , Kammertoens Thomas , Nassenstein Christina , Braun Armin , Blankenstein Thomas , Kempermann Gerd
Published: March 2009

Adult hippocampal neurogenesis occurs in an exceptional permissive microenvironment. Neuroimmunological mechanisms might be prominently involved in the endogenous homeostatic principles that control baseline levels of adult neurogenesis. We show in this study that this homeostasis is partially dependent on CD4-positive T lymphocytes. Systemic depletion of CD4-positive T lymphocytes led to significantly reduced hippocampal neurogenesis, impaired reversal learning in the Morris water maze, and decreased brain-derived neurotrophic factor expression in the brain. No such effect of CD8 or B cells was observed. Repopulation of RAG2−/− mice with CD4, but not with CD8 cells again increased precursor cell proliferation. The T cells in our experiments were non-CNS specific and rarely detectable in the healthy brain. Thus, we can exclude cell-cell contacts between immune and brain cells or lymphocyte infiltration into the CNS as a prerequisite for an effect of CD4-T cells on neurogenesis. We propose that systemic CD4-T cell activity is required for maintaining cellular plasticity in the adult hippocampus and represents an evolutionary relevant communication route for the brain to respond to environmental changes.
Human Benign Prostatic Hyperplasia Stromal Cells As Inducers and Targets of Chronic Immuno-Mediated Inflammation
Authors: Penna Giuseppe , Fibbi Benedetta , Amuchastegui Susana , Cossetti Chiara , Aquilano Francesca , Laverny Gilles , Gacci Mauro , Crescioli Clara , Maggi Mario , Adorini Luciano
Published: March 2009

Benign prostatic hyperplasia (BPH), a highly prevalent prostatic condition, could involve an inflammatory component in disease pathogenesis. In this study, we show that human stromal prostate cells obtained from BPH tissue can actively contribute to the inflammatory process by secreting proinflammatory cytokines as well as chemokines able to recruit lymphomonuclear cells and by acting as APCs. BPH cells express all of the TLRs and their ligation leads to the secretion of CXCL8/IL-8, CXCL10, and IL-6. In addition, BPH cells express costimulatory as well as class I and class II MHC molecules, which activate alloreactive CD4+ cells that in turn markedly up-regulate IL-12/IL-23p40 and IL-12p75 secretion by BPH cells. Alloreactive CD4+ cells activated by BPH cells secrete IFN-γ and IL-17. These cytokines up-regulate IL-6, IL-8, and CXCL10 production by BPH cells, creating a positive feedback loop that can amplify inflammation. IL-8 induces autocrine/paracrine proliferation of BPH cells, indicating also a growth-promoting activity of this chemokine in disease pathogenesis. These results show that human BPH cells represent nonprofessional APCs able to induce and sustain chronic inflammatory processes, supporting the relevance of inflammation in BPH pathogenesis.
CXCR4/CXCL12 Hyperexpression Plays a Pivotal Role in the Pathogenesis of Lupus
Authors: Wang Andrew , Fairhurst Anna-Marie , Tus Katalin , Subramanian Srividya , Liu Yang , Lin Fangming , Igarashi Peter , Zhou Xin J. , Batteux Frederic , Wong Donald , Wakeland Edward K. , Mohan Chandra
Published: March 2009

Among various surface molecules screened, CXCR4 was significantly up-regulated on monocytes, neutrophils, B cell subsets, and plasma cells in multiple murine models of lupus with active nephritis, including B6.Sle1Yaa, BXSB, and MRL.lpr. TLR-mediated signaling and inflammatory cytokines accounted in part for this increase. Increased CXCR4 expression was associated with functional consequences, including increased migration and enhanced B cell survival. Simultaneously, the ligand for CXCR4, CXCL12, was significantly up-regulated in the nephritic kidneys. Treatment with a peptide antagonist of CXCR4 prolonged survival and reduced serum autoantibodies, splenomegaly, intrarenal leukocyte trafficking, and end organ disease in a murine model of lupus. These findings underscore the pathogenic role of CXCR4/CXCL12 in lymphoproliferative lupus and lupus nephritis and highlight this axis as a promising therapeutic target in this disease.
Cutting Edge: A2B Adenosine Receptor Signaling Provides Potent Protection during Intestinal Ischemia/Reperfusion Injury
Authors: Hart Melanie L. , Jacobi Barbara , Schittenhelm Jens , Henn Martina , Eltzschig Holger K.
Published: March 2009

Gastrointestinal ischemia/reperfusion (IR) injury significantly contributes to the morbidity and mortality of critical illness. In this study, we hypothesized a protective role for extracellular adenosine signaling in intestinal IR injury. Initial profiling studies of mucosal scrapings following murine IR demonstrated selective induction of the A2B adenosine receptor (A2BAR) transcript. Moreover, gene-targeted mice for the A2BAR showed more profound intestinal IR injury compared with controls. In contrast, A2AAR−/− mice exhibited no differences in intestinal injury compared with littermate controls. In addition, selective inhibition of the A2BAR resulted in enhanced intestinal inflammation and injury during IR. Furthermore, A2BAR agonist treatment (BAY 60-6583) protected from intestinal injury, inflammation, and permeability dysfunction in wild-type mice, whereas the therapeutic effects of BAY 60-6583 were abolished following targeted A2BAR gene deletion. Taken together, these studies demonstrate the A2BAR as a novel therapeutic target for protection during gastrointestinal IR injury.