bluuebunny/crossref_metadata_2025 huggingface dataset:
High-Strength Filaments for Cables and Lines
Authors: Scala E
Published: March 2009

A review of bundle theory and the strength of yarns compared to single filaments has been made for several high strength filament materials. The dielectric properties and the statistical distribution of tensile strength have been compared for filaments of glass (Types E and S), graphites, and the high modulus PRD-49 (organic). The review was made in conjunction with the development of a new type of a high modulus line using PRD-49 filaments. The lines were to be used as guys for the antennae system at the Arecibo Observatory in Puerto Rico, the National Astronomy and Ionosphere Center which is operated by Cornell University for the National Science Foundation. The unique requirement for these cables was not only the high modulus for a low total elongation of 20 to 90 ft lengths with low loss tangent and dielectric properties, but the need for rigidity at comparatively low prestrain loads.

Varying sizes and designs were produced experimentally, ranging from 15 to 19 000 lb ultimate strengths. The testing of lines involved both precision optical strain measurements on 1 ft gage lengths as well as 10 ft test lengths for elongation, modulus, and strength measurements. The final design involved 1800 ends of 380 denier Type III, PRD-49 duPont fibers. The finished cable has a nominal modulus of 16. 5 Ç 106 psi capable of supporting a 19 000-lb load with a cable weight 0.04 lb/ft of length. For optimum resistance to weathering, moisture, and ultraviolet effects, outer sheathing with extruded black PVC had been used. Epoxy bonded end fittings were employed to permit tension adjustments at the comparatively low leads.
Microbiological Standards for Frozen Foods
Authors: Appleman MD , Appleman MD , Appleman MD
Published: March 2009

Factors predetermining quality and safety of frozen food products along with different types of standards are discussed. Attention is drawn to the fact that microbiological standards for frozen foods must be studied thoroughly prior to establishment. Certain standards of communities have been enacted with haste and regulations involving Standard Plate Counts (SPC) impossible to meet have been promulgated. In order to avoid fiascoes of this nature the Food and Drug Administration (FDA) working with the Advisory Council on Microbiology (ACM) of the Association of Food and Drug Officials of the United States (AFDOUS) has been making intensive studies of foods. To date, microbiological standards have been released for frozen pot pies only. The advisory council, which is composed of persons from industry, educational institutions, and public health agencies, has been evaluating microbiological risks associated with most foods and beverages prior to decisions as to whether or not standards should be established. At present the relative risk involved in each foodstuff or beverage as a possible source of coliforms, faecal coli, faecal streptococci, Salmonella, Shigella, Staphylococcus, Pseudomonas, Clostridium, molds (both as mycotoxin producers and as pathogens,) viruses and other agents involved in toxigenicity or pathogenicity are under study. The sources and methods of transmission of diseases through the agency of frozen foods and methods of evaluating and minimizing risk are clarified. The inherent inconvenience and danger of establishing microbiological standards for foods without careful evaluative techniques are explained. The impact of microbiological standards for foods upon incipient or frank spoilage is discussed.
Thermodynamic and Transport Properties of Cryogenic Propellants and Related Fluids
Authors: Johnson VJ
Published: March 2009

Significant advances have been made in recent years in the quality and range of thermophysical data for the cryogenic propellants, pressurants, and inertants. These advances have resulted from improved evaluation and compilation techniques coupled with better and more extensive experimental data and from a better theoretical understanding of the physical properties of gases. A review of recently completed and current data compilation projects for helium, hydrogen, argon, nitrogen, oxygen, fluorine, and methane will be given as well as recommended references for thermodynamic and transport property data tables for these fluids. Modern techniques in the plotting of thermodynamic charts from tabular data (or from functions such as the equation of state) have greatly improved their precision and value. A list of such charts is included.
Environmental Control of Lunar Samples in the Lunar Receiving Laboratory
Authors: Reynolds MA , Turner NL , Hurgeton JC , Barbee MF , Flory DA , Simoneit BR
Published: March 2009

The arrival on Earth of samples of lunar rocks presented an unparalleled opportunity to expand man's knowledge of the solar system. Close control of the environment was necessary to maintain the integrity of the lunar material. This started with the development of high vacuum (10−6 to 10−8 torr) processing lines which were constructed of materials that would not interfere with the analyses of the lunar samples, and later (Apollo 14) evolved to the use of high-purity nitrogen filled cabinets or glove boxes when the vacuum lines were abandoned. Trace quantities of oxygen, argon, carbon dioxide, carbon monoxide, hydrogen, methane, and water in the nitrogen processing lines were analyzed. During Apollo 14, analysis at 1 in. negative pressure within cabinets, 02 varied between 25 to 50 ppm, and moisture from 85 to 125 ppm. Following the elimination of quarantine restrictions, Apollo 15 samples were processed at a slight positive pressure which further reduced oxygen to 10 to 30 ppm and moisture to 15 to 25 ppm. Equipment and cabinetry interiors were cleaned consistently to low levels of hydrocarbons and particulate contaminants. The maximum allowable hydrocarbons, C10 through C30 was 10 micrograms per square foot of critical surface and flush samples with particles over 750 µm in size required recleaning. This resulted in providing the scientific community with samples whose integrity had not been compromised during preliminary investigations and allocations.
Techniques for the Analysis of Gases Sequentially Released from Lunar Samples
Authors: DesMarais DJ , Hayes JM , Meinschein WG
Published: March 2009

This paper describes two methods for the analysis of light gases that are sequentially evolved from 2 to 10 mg of lunar sample. A hydrofluoric acid hydrolysis of lunar material is achieved by repeated exposure of the sample to hydrogen fluoride. In the second technique, gases are evolved from lunar samples by the stepwise heating of these samples to 1400° C. The gases evolved by either hydrolysis or pyrolysis are analyzed in a gas chromatographic system using a helium ionization detector. The sensitivities of this detector for the gases, as analyzed, range from 2 X 10−1 1 g/s for hydrogen to 2 × 10−1 3 g/s for carbon dioxide.
Corrosion Standards and Control in the Petroleum Industry
Authors: Couper AS
Published: March 2009

Petroleum refineries use water, steam, hydrogen, acids, and a variety of other corrosive materials to convert crude oil into many different products, including gasolines, lubricating oils, fuel oils, and chemical plant feed-stocks. Hence, refineries have not only most of the corrosion problems encountered in the utilities and chemical industries, but a few specific problems as well.
Status Report on Plastics Recycling
Authors: Lawrence JR
Published: March 2009

Although plastics wastes form only a very small portion of the total wastes generated in the United States, considerable concern has been expressed over the environmental damage and nonrecyclability attributed to plastics. The plastics industry has made a careful study of the existing and potential recycle opportunities for plastics, both within the industry and from solid waste material.

The conclusion that is rapidly taking shape as a result of these studies is that the use of waste plastics in an unsorted form for the recovery of energy by either pyrolysis or incineration will probably be the most successful plastics recycling program in the context of present day technology and economics. However, the technology and economic evaluation of these opportunities is still in a development phase. Therefore, until energy recovery is clearly shown to be the optimum reuse of plastics, the plastics industry will continue to support other short-term activities. These activities include programs for sorting plastics from mixed solid waste and economic research for markets for products from such materials. The plastics industry continues to encourage programs that demonstrate that plastics can be recycled if the circumstances are such that clean material of one kind can be obtained in volume quantities.

Since the majority of our collected municipal waste is now going to landfills, it is important to recognize that plastics contribute no particular problems to landfill in that they are nonbiodegradable and compact readily to provide good solid fill in this kind of disposal system.
Correlation of Substructure with the Elevated Temperature Low-Cycle Fatigue of AISI 304 and 316 Stainless Steels
Authors: Challenger KD , Moteff J
Published: March 2009

The dislocation substructure of AISI 304 and 316 stainless steels resulting from high strain fatigue for various strain rates at temperatures ranging from 430 to 816 C has been evaluated by transmission electron microscopy. The substructure is characterized quantitatively and correlated with the observed mechanical behavior. Dislocation cells or subgrains were observed for all test conditions with exception of one test where failure occurred in the high-cycle range. These results suggest that a change in deformation mechanisms appear to occur between 650 and 816 C. The Hollomon strain hardening equation is written in terms of the dislocation cell size for both monotonic and cyclic loading predicting higher strengths and strain hardening capabilities could be effected through cell size refinement.
Fatigue of Protective Metal Oxides in Combustion Chamber Exhaust Gases
Authors: Dils RR
Published: March 2009

An analysis of the oxidation of an aluminized nickel-base alloy in the exhaust gases of a gas turbine main burner has been developed. Characterizations of combustion chamber exhaust gases and the temperature fluctuations induced at fireside surfaces by the exhaust gases are reviewed, and the analyses are applied to the description and simulation of the exhaust gases of a gas turbine main burner. The results of wide bandwidth gas temperature measurements at the entrance to the turbine section of a large gas turbine are used to obtain metalmetal oxide interface temperature waves at the surface of the turbine components. Simulations of the interface temperature wave in exhaust gases of laboratory combustion chambers and oxidation experiments in the laboratory combustor exhaust gases are presented. It is shown that the small fluctuations induced at the surface of the turbine components by the main burner exhaust gases can be of sufficient amplitude to affect the rate of oxidation of the turbine components. The example temperature fluctuations measured in the gas turbine cause the growth of a porous nonprotective oxide on the surface of the aluminized nickel-base alloy. A continual loss of the oxide results in a significant increase in the rate of oxidation of the material.
Discussion of the Test Method and Equipment for the Evaluation of Low-Cycle Creep-Fatigue Failure Criteria
Authors: Schneiderovitch RM , Gusenkov AP
Published: March 2009

The formulation of failure criteria for cyclic loading at elevated temperature must be based on a large quantity of experimental data. The design of the experiments and the particular test method used for such formulation is the subject of this paper. Several schemes for controlling the independent variables are described, and the requirements for isothermal and cyclic thermal creep and fatigue tests with load or strain control provision are illustrated by equipment developed at the author's laboratory.
Effects of Grain Size and Temperature on the Cyclic Strength and Fracture of Iron
Authors: Abdel-Raouf H , Topper TH , Plumtree A
Published: March 2009

The influence of grain size on the cyclic deformation behavior and fracture of Ferrovac E iron under low-cycle fatigue conditions are studied at temperatures ranging from 23 to 540C and strain range of 0.010. The steady-state stress response and the related cell size are independent of the grain size. The cell size and the total dislocation density was found to depend markedly on the dynamic strain aging level. The inhomogenity of plastic deformation in the material was enhanced by dynamic strain aging. This inhomogeneity was observed by both surface damage studies and substructural investigations. The grain size has no effect on the redistribution of plastic strains. The fracture mechanism and fatigue life was dependent on the dynamic strain aging level through the degree of redistribution of plastic strains. The dependency of fatigue life on grain size is controlled by the fracture mechanism available at this temperature. At high dynamic strain aging levels, the material reveals brittle striations on the fracture surfaces. In this case, the fracture process is independent on the grain boundary resistance and life is independent of the grain size.
Analytical and Experimental Study of Thermal Ratchetting
Authors: Swaroop AVA , McEvily AJ
Published: March 2009

The process of thermal ratchetting has been investigated both analytically and experimentally, with a three-bar assembly used as a basis. Steel specimens have been tested under stress during thermal cycling between room temperature and 600 C. Good agreement between experimental results and an improved analytical treatment have been obtained.
Ductility Exhaustion Model for Prediction of Thermal Fatigue and Creep Interaction
Authors: Polhemus JF , Spaeth CE , Vogel WH
Published: March 2009

Extensive laboratory testing of typical alloys used in gas turbine blading has shown that there is a strong interaction of the thermal fatigue and creep damage modes which is nonlinear in nature. Consequently, a model for cumulative damage analysis was developed using an exhaustion of ductility concept in which the total available ductility is derived from baseline thermal fatigue tests or, alternatively, estimated from stress-rupture tests. A cycle-by-cycle reckoning of ductility used and remaining is made with the use of a digital computer program, and cracking is ultimately predicted at the point where the remaining ductility is insufficient to complete another cycle.

The developed analysis is shown to correlate with laboratory test results. The understanding and design procedure developed make it possible to simulate complex service conditions in digital computer programs and evaluate designs and materials in simulated “fly offs.”
Codes: Asset or Liability?
Authors: Cooper WE
Published: March 2009

Elevated temperature fatigue evaluation rules are now included in the ASME Codes which govern the construction of nuclear power plant components. This paper considers the general question as to whether such Codes consitute an asset or a liability, and the specific question concerning asset versus liability as it relates to elevated temperature fatigue.

It is concluded that the present rules with respect to elevated fatigue represent a liability. The background of this situation is discussed and suggestions are made with respect to the steps required for conversion to an asset.
Tennessee's Inventory of Pavement Skid Resistance
Authors: Goodwin WA , Moore AB
Published: March 2009

Tennessee has been continuously engaged in skid resistance and corrective action research since 1952. A new program was initiated in July 1970 as a specific effort of inventorying the present skid resistant level of the State's primary highway system. The skid resistance level is measured with the University's two-wheel skid trailers that essentially meet the requirements of ASTM designation E 274 using the standard ASTM E 249 tire. The skid tests are performed on wetted pavements at a constant speed of 40 mph. Tests are conducted at intervals of approximately one-half mile or less in the inner wheel path of both lanes of the pavement. To date, 66 counties of the 95 counties within the State have been surveyed. This amounts to about 48 percent of the total rural highway mileage. For each test section base data on roadway goemetry, pavement surface characteristics, pavement type and date of construction, and the length of the test section are recorded for future evaluation.

The results of the skid measurements are summarized in tabular form and presented graphically. The graphical form depicts the measured skid number or coefficient of friction as related to the log mile along the highway surface. This type presentation provides a continuous log of the changes in skid number throughout a particular pavement construction section. In some instances, it can be readily seen that the type of construction influences the skid resistance level. Also, variations within a construction section can be readily identified. The results of the inventory are reported systematically to the State Highway Department, and, where indicated, corrective measures are taken. The corrective action may be complete resurfacing with a hot plant mix or the application of a seal coat.

Although intensive field and laboratory research has been sponsored during the past 19 years by the Highway Department, this project of inventorying all primary highway surfaces affords a systematic opportunity of pinpointing surfaces of questionable skid resistance level for corrective action. It is anticipated that the inventory and corrective action program will result in maintaining a satisfactory level of skid resistance on the roadway throughout the State and hopefully will result in the reduction of accidents. The data collected relative to characterizing the pavement surface and roadway goemetry will be useful in improving pavement design and construction techniques.
Measurement Principles Applied to Skid Testing
Authors: Hegmon RR , Gillespie TD , Meyer WE
Published: March 2009

The real objective in skid testing is to determine the contribution of the pavement to tire-pavement friction. Friction force between a standard tire and the pavement is measured because there is, at present, no direct way of characterizing the pavement surface. Friction force depends on pavement and tire; therefore, the tire cannot properly be regarded as part of the measuring system. The skid tester, without tire, is discussed on principles of measurement techniques, and the conclusion is reached that statistical methods must be employed to compensate for the lack of precision in skid testing. Skid tester dynamics do not affect mean skid resistance; therefore, no basic design changes are required. Precision can be improved by tighter test procedures. These require improved training and awareness of operators, improved control of test speed, lateral position, and pavement watering.
Biological Methods for the Assessment of Water Quality
Authors: Cairns J , Dickson KL
Published: March 2009

Description

The Symposium on Biological Methods for the Assessment of Water Quality was presented at the Seventy-fifth Annual Meeting of ASTM held in Los Angeles, Calif., 26-29 June 1972. The symposium was sponsored by Committee D19 on Water, and was designed to form Subcommittee D19.01 on Biological Monitoring. John Cairns, Jr. and K. L. Dickson, Virginia Polytechnic Institute and State University, presided as cochairmen.
Calcium-barium sulfo-ferritealuminate series minerals
Authors: Pan Z. , Liu Q. , Ye Z. , Chang J.
Published: March 2009

Based on the dominant mineral in barium-bearing sulfoaluminate calcium cement C2·75B1·25A3S¯, the calcium-barium sulfo-ferritealuminate series minerals were synthesised by replacing Al3+ with a different equivalent of Fe3+. The microstructure was investigated by means of X-ray diffraction, dynamic thermal analysis/thermogravimetric analysis, scanning electron microscopy–energy dispersive spectroscopy (SEM–EDS). The results indicated that the optimal molar composition of Fe3+ ions was from 0·5 to 1·7. The optimum composition was C2·75B1·25A1·5Fe1·5S¯. At this level, the strength at 1, 3 and 28 days could reach 64, 77·75 and 86·62 MPa, respectively.
Modelling of cryogenic processes in permafrost and seasonally frozen soils
Authors: Thomas H. R. , Cleall P. , Li Y.-C. , Harris C. , Kern-Luetschg M.
Published: March 2009

This paper investigates the thermo-hydro-mechanical (THM) behaviour of soils subjected to seasonal temperature variations in both permafrost and seasonally frozen conditions. Numerical modelling of soil freezing and ice segregation processes is presented, and compared against small-scale physical modelling experiments. The coupled THM model presented, which is solved by way of a transient finite element approach, considers a number of processes, including conduction, convection, phase change, the movement of moisture due to cryogenic suctions, and the development of ice lenses. Two seasonal freezing scenarios are considered: (a) for soils with no permafrost, where freezing is from the surface downward (one-sided freezing); and (b) for soils underlain by permafrost, where large thermal gradients in the uppermost permafrost layer can cause active layer freezing in two directions, from the permafrost table upwards and from the ground surface downwards (two-sided freezing). In the case of one-sided freezing, ice lens formation occurs as the freezing front advances downwards from the surface, and is limited by water supply. However, during two-sided freezing, ice segregation takes place in a closed system, with ice lenses accumulating at the base of the active layer and near the ground surface, leaving an intervening ice-poor zone. Numerical modelling is able to represent the development of both the thermal field and ice segregation observed in the physical models. The significance of this contrasting ground ice distribution is considered in the context of thaw-related slow mass movement processes (solifluction).
Modelling the thermomechanical volume change behaviour of compacted expansive clays
Authors: Tang A.-M. , Cui Y.-J.
Published: March 2009

Compacted expansive clays are often considered as a possible buffer material in high-level deep radioactive waste disposals. After the installation of waste canisters, the engineered clay barriers are subjected to thermohydromechanical action in the form of water infiltration from the geological barrier, heat dissipation from the radioactive waste canisters, and stresses generated by clay swelling under almost confined conditions. The aim of the present work is to develop a constitutive model that is able to describe the behaviour of compacted expansive clays under these coupled thermo-hydromechanical actions. The proposed model is based on two existing models: one for the hydromechanical behaviour of compacted expansive clays and another for the thermomechanical behaviour of saturated clays. The elaborated model has been validated using thermo-hydromechanical test results on compacted MX80 bentonite. Comparison between the model prediction and the experimental data shows that this model is able to reproduce the main features of volume changes: heating at constant suction and pressure induces either expansion or contraction; the mean yield stress changes with variations of suction or temperature.
Energy pile test at Lambeth College, London: geotechnical and thermodynamic aspects of pile response to heat cycles
Authors: Bourne-Webb P. J. , Amatya B. , Soga K. , Amis T. , Davidson C. , Payne P.
Published: March 2009

Very limited information is available regarding the impact of heating and cooling processes on the geotechnical performance of piled foundations incorporating pipe loops for ground-source heat-pump systems (so-called energy piles). A pile-loading test that incorporated temperature cycles while under an extended period of maintained loading was undertaken to investigate the behaviour of an energy pile installed in London Clay. Testing was carried out over a period of about seven weeks, with conventional loading tests carried out either side of an extended loading test with thermal cycles. Using an optical fibre sensor system, and other more conventional instrumentation, temperature and strain profiles were observed in the test pile, an adjacent bore-hole, two of the anchor piles, and the heat sink pile. Details of load and movement at the pile head, of ambient air temperature and of the input/output temperature of fluid within the heating system were also recorded. Thermodynamic behaviour observed during the test supports the assumption that the pile acts as an infinitely long heat sink/source, and that the conductivity values used for the London Clay were reasonable. Forces mobilised in the pile shaft and the resistance mobilised at the pile/soil interface have been inferred from the test response, and the effects have been described using a simplified mechanism. Concrete stresses additional to those due to static loading are generated when the pile is heated, and the pile end-restraint conditions influence the effect; concrete stresses could potentially exceed the limiting values imposed by design codes. In this case there was a large margin between the pile ultimate shaft resistance and the shear stresses mobilised at the pile/soil interface during thermal cycling, and as a consequence, it is considered unlikely that the geotechnical capacity of the pile was affected significantly.
Direct Osmosis for Reverse Osmosis Fouling Control: Principles, Applications and Recent Developments
Authors: Qin Jian-Jun , Liberman Boris , A. Kekre Kiran , Gossan Ado
Published: March 2009

Reverse osmosis (RO) has been widely applied in various water and wastewater treatment processes as a promising
membrane technology. However, RO membrane fouling is a global issue, which limits it operating flux, decreases
water production, increases power consumption and requires periodical membranes Cleaning-in-Place (CIP) procedure.
This may result in low effectiveness, high cost and adds environmental issues related to the CIP solutions disposal. Forward
osmosis (FO) or direct osmosis (DO) is the transport of water across a semi-permeable membrane from higher water
chemical potential side to lower water chemical potential side, which phenomenon was observed in 1748. The engineered
applications of FO/DO in membrane separation processes have been developed in food processing, wastewater treatment
and seawater/brackish water desalination. In recent years, DO has been increasingly attractive for RO fouling control as it
is highly efficient and environmentally friendly technique which is a new backwash technique via interval DO by intermittent
injection of the high salinity solution without stoppage of high pressure pump or interruption of the operational
process and allows keeping RO membrane continuously clean even in heavy bio-fouling conditions and operating RO
membranes at high flux. This paper provides the state-of-the-art of the physical principles and applications of DO for RO
fouling control as well as its strengths and limitations.
Studying Reading Instruction With Teacher Logs: Lessons From the Study of Instructional Improvement
Authors: Rowan Brian , Correnti Richard
Published: March 2009

This article describes some of the conceptual and methodological issues that arise when researchers use teacher logs to measure classroom instruction. Data and examples come from the Study of Instructional Improvement, which used teacher logs to study patterns of literacy instruction in schools implementing three comprehensive school reforms. Over the course of this study, more than 75,000 logs were collected from nearly 2,000 teachers in Grades 1 through 5. This article discusses why teacher logs were chosen as the data collection strategy, various psychometric issues associated with their use, and some of the substantive findings that emerged as part of the study.
“Where Is the Action?” Challenges to Studying the Teaching of Reading in Elementary Classrooms
Authors: Croninger Robert G. , Valli Linda
Published: March 2009

The authors argue that part of the difficulty in studying the teaching of reading in elementary classrooms is determining where “the action” occurs in reading instruction. Based on their 5-year longitudinal study of fourth- and fifth-grade teachers in moderate- and high-poverty elementary schools, they describe three challenges: (a) determining key factors in the complex instructional environment that should be the focus of study, (b) determining who teaches reading to specific students, and (c) determining the boundaries of reading instruction or when it occurs during the school day and year. The authors argue that these challenges, although not insurmountable, are difficult to resolve and that they are becoming more pervasive because of current policies that promote high-stakes accountability.
The Blacksmiths of Tamale: The Dynamics of Space and Time in a Ghanaian Industry
Authors: MacGaffey Wyatt
Published: March 2009

In the last twenty years the number of smiths and the range of their activity have greatly increased in Tamale, the principal city of northern Ghana. The evolution of the national economy and the particular situation of Tamale in the geography of Ghana explain this development and the contribution that the city's smiths make to the economy, national as well as local.
The Re(Public) of Salsa: Afro-Cuban Music in Fin-de-Siècle Dakar
Authors: Shain Richard M.
Published: March 2009

This article explores why, despite its diminished popularity, Afro-Cuban music remains among the most performed musics in Senegalese music clubs. Since the Second World War, many Senegalese have associated Afro-Cuban music with cosmopolitanism and modernity. In particular, Senegalese who came of age during the Independence era associate Latin music with a new model of sociability that emphasized ‘correct’ behaviour – elegant attire and self-discipline. Participating in an emerging ‘café society’ was especially important. The rise of m'balax music in the late 1970s, deemed more culturally ‘authentic’ by a younger generation coming into its own, challenged many of the values associated with Senegalese salsa. As an enlarged Senegalese public embraced m'balax, the older generation stopped going out to Dakar's nightclubs where they felt increasingly uncomfortable. However, the model of sociability this generation has championed calls for public displays of distinction and refinement. In fin-de-siècle Dakar, a number of venues emerged where Afro-Cuban music is played and powerful older Dakarois congregate, even if less frequently than formally. This article describes these venues and documents their patrons and the performances that take place there.
ROV Mateable Electrical Connector
Authors: Pye D.B.
Published: March 2009

Growth of the Requirement

"There is no more easy oil!"

This statement above all others symbolises the changes of emphasis in therecovery of oil and gas reserves in all parts of the world. With exceptionpossibly of the CIS and the former Soviet Republics, it is unlikely thatdiscoveries of reserves even approaching the size of the smaller North Seafields will be discovered in areas that allow exploitation by the technologiesof the 1980's.

The discovery of marginal reserves in the North Sea has led to theinvestigation of various new approaches to their exploitation such as Sub-seaseparation, multiphase pumping, Sub-sea wellheads, production facilities andFloating Production vessels to name but a few. This increase in the use ofsub-sea facilities has been allied to a dramatic improvement in the reliabilityof electrical equipment in general and sub-sea connectors in particular.

The development of a new family of connectors to satisfy this changingmarket has taken place over the last few years and has now reached a stagewhere a number of independent solutions are available in the marketplace. Thesetake widely differing approaches to the problem all having their own perceivedadvantages and disadvantages. Discussions over these could be the subject of aseparate paper!

Other factors influencing the growth of the requirement are:The move to deeper waters - This imposes an obvious restriction on theuse of Divers and makes remote handling an essential factor in the viability ofa reserve, not just an option.Diving Regulations - The tightening up of the parameters for divingoperations has had a significant impact on the cost effectiveness of their useand, more likely than not, these will become even more restrictive in thefuture. It is however possible to retain some of the advantages of a diver, without infringing these regulations, by the use of an Atmospheric DivingSystem as will be discussed later.Costs - In general it will be possible to make savings on installation costsby the use of remote installation techniques. Time on site can be greatlyreduced and the capital cost of the equipment utilised should be also reduced. Against this however must be set the possible increase in structure complexityto accommodate the ROV/Tooling package to be used.
One‐Dimensional Conducting Polymer Nanostructures: Bulk Synthesis and Applications
Authors: Tran Henry D. , Li Dan , Kaner Richard B.
Published: March 2009

This Progress Report provides a brief overview of current research activities in the field of one‐dimensional (1D) conducting polymer nanostructures. The synthesis, properties, and applications of these materials are outlined with a strong emphasis on recent literature examples. Chemical methods that can produce 1D nanostructures in bulk quantities are discussed in the context of two different strategies: 1) procedures that rely on a nanoscale template or additive not inherent to the polymer and 2) those that do not. The different sub‐classifications of these two strategies are delineated and the virtues and vices of each area are discussed. Following this discussion is an outline of the properties and applications of 1D conducting polymer nanostructures. This section focuses on applications in which nanostructured conducting polymers are clearly advantageous over their conventional counterparts. We conclude with our perspective on the main challenges and future research directions for this new class of nanomaterials. This Progress Report is not intended as a comprehensive review of the field, but rather a summary of select contributions that we feel will provide the reader with a strong basis for further investigation into this fast emerging field.
Growth perturbations in a phenotype with rapid fetal growth preceding preterm labor and term birth
Authors: Lampl Michelle , Kusanovic Juan Pedro , Erez Offer , Gotsch Francesca , Espinoza Jimmy , Goncalves Luis , Lee Wesley , Gomez Ricardo , Nien Jyh Kae , Frongillo Edward A. , Romero Roberto
Published: March 2009

The variability in fetal growth rates and gestation duration in humans is not well understood. Of interest are women presenting with an episode of preterm labor and subsequently delivering a term neonate, who is small relative to peers of similar gestational age. To further understand these relationships, fetal growth patterns predating an episode of preterm labor were investigated. Retrospective analysis of fetal biometry assessed by serial ultrasound in a prospectively studied sample of pregnancies in Santiago, Chile, tested the hypothesis that fetal growth patterns among uncomplicated pregnancies (n = 3,706) and those with an episode of preterm labor followed by term delivery (n = 184) were identical across the time intervals 16–22 weeks, 22–28 weeks, and 28–34 weeks in a multilevel mixed‐effects regression. The hypothesis was not supported. Fetal weight growth rate was faster from 16 weeks among pregnancies with an episode of preterm labor (P < 0.05), declined across midgestation (22–28 weeks, P < 0.05), and rebounded between 28 and 34 weeks (P = 0.06). This was associated with perturbations in abdominal circumference growth and proportionately larger biparietal diameter from 22 gestational weeks (P = 0.03), greater femur (P = 0.01), biparietal diameter (P = 0.001) and head circumference (P = 0.02) dimensions relative to abdominal circumference across midgestation (22–28 weeks), followed by proportionately smaller femur diaphyseal length (P = 0.02) and biparietal diameter (P = 0.03) subsequently. A distinctive rapid growth phenotype characterized fetal growth preceding an episode of preterm labor among this sample of term‐delivered neonates. Perturbations in abdominal circumference growth and patterns of proportionality suggest an altered growth strategy pre‐dating the preterm labor episode. Am. J. Hum. Biol., 2009. © 2009 Wiley‐Liss, Inc.
Interactions between metabolic and reproductive functions in the resumption of postpartum fecundity
Authors: Valeggia Claudia , Ellison Peter T.
Published: March 2009

Lactation has long been recognized as a major determinant of interbirth intervals. The temporal pattern of nursing has been proposed as the mechanism behind lactational amenorrhea. We present a new model of the dynamic regulation of lactational amenorrhea that identifies maternal energy availability as the main determinant of ovarian resumption. Variation in the intensity of lactation remains a component of the model as a determinant of the absolute energetic cost of milk production. However, maternal energy supply determines net energy availability; a larger energy supply leaves a greater net energy surplus than a smaller energy supply (lactation costs being equal). We characterize the hormonal postpartum profile of 70 lactating Toba women of Argentina. We use C‐peptide, which reflects maternal insulin production, as a measure of energy availability. Initially low, insulin production rises as the postpartum period progresses, reflecting the declining metabolic load of lactation. A short period of supernormal insulin production precedes menstrual resumption. The high levels of insulin may play a role in stimulating the resumption of ovarian activity, which in turn may help to resolve the transient period of insulin resistance. The dynamics of insulin sensitivity during lactation would aid in synchronizing the resumption of ovarian function with a reduction in the energy demands of milk production. This hypothesis is supported by the sustained weight gain experienced by lactating women during the months preceding the first postpartum menses. The link between fecundity and energy balance could serve as a mechanism for adjusting the duration of lactational amenorrhea to the relative metabolic load of lactation. Am. J. Hum. Biol., 2009. © 2009 Wiley‐Liss, Inc.
Memantine and constraint‐induced aphasia therapy in chronic poststroke aphasia
Authors: Berthier Marcelo L. , Green Cristina , Lara J. Pablo , Higueras Carolina , Barbancho Miguel A. , Dávila Guadalupe , Pulvermüller Friedemann
Published: March 2009

Objective

We conducted a randomized, double‐blind, placebo‐controlled, parallel‐group study of both memantine and constraint‐induced aphasia therapy (CIAT) on chronic poststroke aphasia followed by an open‐label extension phase.

Methods

Patients were randomized to memantine (20mg/day) or placebo alone during 16 weeks, followed by combined drug treatment with CIAT (weeks 16–18), drug treatment alone (weeks 18–20), and washout (weeks 20–24), and finally, an open‐label extension phase of memantine (weeks 24–48). After baseline evaluations, clinical assessments were done at two end points (weeks 16 and 18), and at weeks 20, 24, and 48. Outcome measures were changes in the Western Aphasia Battery‐Aphasia Quotient and the Communicative Activity Log.

Results

Twenty‐eight patients were included, and 27 completed both treatment phases. The memantine group showed significantly better improvement on Western Aphasia Battery‐Aphasia Quotient compared with the placebo group while the drug was taken (week 16, p = 0.002; week 18, p = 0.0001; week 20, p = 0.005) and at the washout assessment (p = 0.041). A significant increase in Communicative Activity Log was found in favor of memantine‐CIAT relative to placebo‐CIAT (week 18, p = 0.040). CIAT treatment led to significant improvement in both groups (p = 0.001), which was even greater under additional memantine treatment (p = 0.038). Beneficial effects of memantine were maintained in the long‐term follow‐up evaluation, and patients who switched to memantine from placebo experienced a benefit (p = 0.02).

Interpretation

Both memantine and CIAT alone improved aphasia severity, but best outcomes were achieved combining memantine with CIAT. Beneficial effects of memantine and CIAT persisted on long‐term follow‐up. Ann Neurol 2009;65:577–585
Anticonvulsant and antiepileptic actions of 2‐deoxy‐D‐glucose in epilepsy models
Authors: Stafstrom Carl E. , Ockuly Jeffrey C. , Murphree Lauren , Valley Matthew T. , Roopra Avtar , Sutula Thomas P.
Published: March 2009

Objective

Conventional anticonvulsants reduce neuronal excitability through effects on ion channels and synaptic function. Anticonvulsant mechanisms of the ketogenic diet remain incompletely understood. Because carbohydrates are restricted in patients on the ketogenic diet, we evaluated the effects of limiting carbohydrate availability by reducing glycolysis using the glycolytic inhibitor 2‐deoxy‐D‐glucose (2DG) in experimental models of seizures and epilepsy.

Methods

Acute anticonvulsant actions of 2DG were assessed in vitro in rat hippocampal slices perfused with 7.5mM [K+]o, 4‐aminopyridine, or bicuculline, and in vivo against seizures evoked by 6Hz stimulation in mice, audiogenic stimulation in Fring's mice, and maximal electroshock and subcutaneous pentylenetetrazol (Metrazol) in rats. Chronic antiepileptic effects of 2DG were evaluated in rats kindled from olfactory bulb or perforant path.

Results

2DG (10mM) reduced interictal epileptiform bursts induced by 7.5mM [K+]o, 4‐aminopyridine, and bicuculline, and electrographic seizures induced by high [K+]o in CA3 of hippocampus. 2DG reduced seizures evoked by 6Hz stimulation in mice (effective dose [ED]50 = 79.7mg/kg) and audiogenic stimulation in Fring's mice (ED50 = 206.4mg/kg). 2DG exerted chronic antiepileptic action by increasing afterdischarge thresholds in perforant path (but not olfactory bulb) kindling and caused a twofold slowing in progression of kindled seizures at both stimulation sites. 2DG did not protect against maximal electroshock or Metrazol seizures.

Interpretation

The glycolytic inhibitor 2DG exerts acute anticonvulsant and chronic antiepileptic actions, and has a novel pattern of effectiveness in preclinical screening models. These results identify metabolic regulation as a potential therapeutic target for seizure suppression and modification of epileptogenesis. Ann Neurol 2009;65:435–448.
Decreased ventilatory response to hypercapnia in dementia with Lewy bodies
Authors: Mizukami Katsuyoshi , Homma Toshiaki , Aonuma Kazutaka , Kinoshita Toru , Kosaka Kenji , Asada Takashi
Published: March 2009

A systematic autonomic dysfunction observed among patients with dementia with Lewy bodies (DLB) has recently attracted close attention. Here, we compare cardiovascular and pulmonary autonomic functions among patients with DLB, patients with Alzheimer's disease, and healthy control subjects. All 15 DLB patients demonstrated severely low ventilatory response to hypercapnia, whereas none of the other subjects demonstrated abnormal results. The majority of the DLB patients showed impaired heart rate variability, low uptake on 123I‐metaiodobenzylguanidine myocardial scintigraphy, and orthostatic hypotension. Ventilatory response to hypercapnia as a marker of respiratory autonomic function is a promising diagnostic tool for DLB. Ann Neurol 2009;65:614–617
Fulminant JC virus encephalopathy with productive infection of cortical pyramidal neurons
Authors: Wüthrich Christian , Dang Xin , Westmoreland Susan , McKay John , Maheshwari Atul , Anderson Matthew P. , Ropper Allan H. , Viscidi Raphael P. , Koralnik Igor J.
Published: March 2009

The polyomavirus JC (JCV) is the causative agent of progressive multifocal leukoencephalopathy and of JCV granule cell neuronopathy. We present a human immunodeficiency virus–negative patient who experienced development of multiple cortical lesions, aphasia, and progressive cognitive decline after chemotherapy for non–small‐cell lung cancer. Brain biopsy and cerebrospinal fluid polymerase chain reaction demonstrated JCV, and she had a rapidly fatal outcome. Postmortem analysis showed diffuse cortical lesions and areas of necrosis at the gray–white junction. Immunostaining showed a productive JCV infection of cortical pyramidal neurons, confirmed by electron microscopy, with limited demyelination. This novel gray matter syndrome expands the scope of JCV clinical presentation and pathogenesis. Ann Neurol 2009;65:742–748
Selective enhancement of rapid eye movement sleep by deep brain stimulation of the human pons
Authors: Lim Andrew S. , Moro Elena , Lozano Andres M. , Hamani Clement , Dostrovsky Jonathan O. , Hutchison William D. , Lang Anthony E. , Wennberg Richard A. , Murray Brian J.
Published: March 2009

Animal studies suggest that rapid eye movement (REM) sleep is governed by the interaction of REM‐promoting and REM‐inhibiting nuclei in the pontomesencephalic tegmentum. The pedunculopontine nucleus is proposed to be REM promoting. Using polysomnography, we studied sleep in five parkinsonian patients undergoing unilateral pedunculopontine nucleus deep brain stimulation (DBS). We demonstrated a near doubling of nocturnal REM sleep between the DBS “off” and DBS “on” states, without significant changes in other sleep states. This represents the first demonstration that DBS can selectively modulate human sleep, and it supports an important role for the pedunculopontine nucleus region in modulating human REM sleep. Ann Neurol 2009;66:110–114
Neuromuscular involvement in various types of Ehlers–Danlos syndrome
Authors: Voermans Nicol C. , van Alfen Nens , Pillen Sigrid , Lammens Martin , Schalkwijk Joost , Zwarts Machiel J. , van Rooij Iris A. , Hamel Ben C. J. , van Engelen Baziel G.
Published: March 2009

Objective

Ehlers–Danlos syndrome (EDS) is a clinically and genetically heterogeneous group of heritable connective tissue disorders characterized by joint hypermobility, skin hyperextensibility, and tissue fragility. Muscle involvement is plausible based on recently discovered interactions between muscle cells and extracellular matrix molecules; however, muscle symptoms are only sporadically reported. We designed a cross‐sectional study to find out whether neuromuscular features are part of EDS.

Methods

Standardized questionnaires, physical examination, nerve conduction studies, electromyography, muscle ultrasound, and muscle biopsy were performed in 40 EDS patients with the vascular, classic, tenascin‐X (TNX)–deficient type EDS, and hypermobility type of EDS caused by TNXB haploinsufficiency.

Results

Muscle weakness, myalgia, and easy fatigability were reported by the majority of patients. Mild‐to‐moderate muscle weakness (85%) and reduction of vibration sense (60%) were common. Nerve conduction studies demonstrated axonal polyneuropathy in five patients (13%). Needle electromyography myopathic features in nine patients (26%) and a mixed neurogenic‐myopathic pattern in most (60%). Muscle ultrasound showed increased echo‐intensity (48%) and atrophy (50%). Mild myopathic features were seen on muscle biopsy of five patients (28%). Overall, patients with the hypermobility type EDS caused by TNXB haploinsufficiency were least affected.

Interpretation

Mild‐to‐moderate neuromuscular involvement is common in various types of EDS, with a remarkable relation between residual TNX level and degree of neuromuscular involvement, compatible with a dose–effect relation. The findings of this study should increase awareness of neuromuscular symptoms in EDS patients and improve clinical care. They also point to a role of the extracellular matrix in muscle and peripheral nerve function. This is an updated version of this article that originally published online on June 29, 2009. Ann Neurol 2009;65:687–697