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Marine protected areas (MPAs) are increasingly being established to protect and rebuild coastal and marine ecosystems. However, while the high seas are increasingly subject to exploitation, globally few MPAs exist in areas beyond national jurisdiction. In 2010 a substantial step forward was made in the protection of high seas ecosystems with 286,200 km 2 of the North-East Atlantic established as six MPAs. Here a summary is presented of how the world's first network of high seas marine protected areas was created under the OSPAR Convention, the main challenges and a series of key lessons learned, aiming to highlight approaches that also may be effective for similar efforts in the future. It is concluded that the designation of these six MPAs is just the start of the process and to achieve ecological coherence and representativity in the North-East Atlantic, the network will have to be complemented over time by additional MPA sites.

The 2005 EPA greenhouse gas emissions inventory estimates that in 2003 total U.S. greenhouse gases were 6900.2 Tg CO 2 Eq. of which 486.4 Tg CO2 Eq. was from agriculture . The contribution of greenhouse gases from agriculture was estimated to be 7.0% of the total emissions. Using the same methodology, EPA estimated that 1990 contributions from agriculture were 418.4 Tg CO 2 Eq. In EPA estimates, contributors to the inventory include methane from enteric fermentation and manure management, and N 2 O from manure management and agricultural soils management. The category agricultural soils management includes N 2 O emissions from pasture, range and paddock distribution, synthetic fertilizer use, sewage sludge application, and some other cropping practices. Other contributors to the agriculture sector include livestock facility fuel and power associated emissions, as well as fuel-CO 2 and N 2 O from growth and processing of the crops consumed by livestock. To date, these other contributions are not separately identified by economic sector in any available U.S. inventory. Adding the categories currently unaccounted for into the agricultural inventory would be expected to increase the total from 486.4 to approximately 670 Tg CO 2 Eq. and the livestock sector contribution could reach approximately 380 Tg/year CO 2 Eq.

Weeds cause considerable yield losses in irrigated rice in West Africa, particularly where sub-optimal crop management or limited resources hamper production. Because of the recent focus of regional breeding programs in West Africa on a wide diversity of interspecific (O. sativa indica×O. glaberrima) and intraspecific (O. sativa×O. sativa) crosses for lowland systems, new genotypes with promising yield potential and putatively improved weed competitiveness are now available. Our study intended to establish a screening methodology for weed competitiveness in irrigated lowlands, to evaluate weed competitive abilities of diverse rice genotypes, and to relate several morphological plant characteristics with competitive abilities. A selection of 25 cultivars and advanced breeding lines was grown under irrigated conditions during the 2000 wet season (WS) and the 2001 dry season (DS) at Ndiaye (Senegal), and their reaction to four different competition levels was assessed. Competition was greatest where the test lines were grown with a mixture of an improved O. sativa indica cultivar and natural weed growth. Average yield losses across rice lines were 36% in the WS and 31% in the DS, but differences between lines were highly significant in both seasons and yield losses ranged from 0 to 84%. Competitive abilities were not related to yields without competition. In the DS, several of the new lines combined high yield with good competitiveness and outperformed the currently widely used check variety. Height, tiller density, specific leaf area (SLA), leaf area index (LAI), and growth duration were mostly negatively related to yield loss. Plant characteristics measured in monoculture had no explanatory value for the competitive ability of tested lines, indicating that screening under conditions of competition with weeds is preferable. Competitive abilities of several lines were stable across sites, years, and seasons; in others, they were strongly influenced by season. The simplified experimental layout can be used to screen advanced breeding lines or established cultivars with moderate resources (e.g., space, seed, labour). Including such a screening in the breeding process would enable more weed competitive cultivars to be identified and would be likely to contribute to increased resource-use efficiency, reduced yield losses, lower costs, and less reliance on herbicides in rice-based lowland systems.

Integrated Coastal Management in the Russian Federation is in its infancy. For the Kaliningrad Region, which has a strategically important coastline, coastal planning and coastal management practitioners will be important in the future. An academic partnership between Kaliningrad State Technical University in the Russian Federation and Southampton Institute in the United Kingdom has developed a specialization in Integrated Coastal Management within the established undergraduate fishery science courses. Materials development has been drawn from western sources, Kaliningrad Region case study opportunities and external links. Initial research into prospects for graduates from this course of study is encouraging and students interest in the new course has been significant. Future aspirations include broadening the academic network within the Russian Federation and Baltic area, and developing additional Russian language teaching material.

The authors' adaptive resampling approach surpasses previous decision-tree performance and validates the effectiveness of small, pooled local dictionaries. They demonstrate their approach using the Reuters-21578 benchmark data and a real-world customer E-mail routing system.

The magnetic circular dichroism (MCD) spectrum of 3.0 mol% Er+3 doped aluminosilicate glass has been measured over a range of temperatures in several optical absorption bands. The method of moments was used to obtain the Faraday A1, B0, and C0 parameters from the spectra, and the spectroscopic splitting factor, g, for the 4I15/2 ground state was calculated for each band studied. The ground state g was also calculated from the saturation properties of the magnetic circular dichroism signal vs. magnetic field strength at 1.6 K. The gs obtained by both methods show very good agreement with each other and are compared with those found in previous works.

Summary Horse manure management is becoming a major concern in suburban areas of the United States. An average horse can produce eight to ten tons of manure per year, accumulating at a rate of two cubic feet per day, including bedding. If properly composted, the manure and bedding can be transformed into a very useful, odorless, pathogenfree product. The objective of this trial was to compare the characteristics of recycled chopped phone book paper, sawdust and wheat straw bedding during composting. Six horses were stalled on three bedding types: recycled phone book paper, sawdust and straw. Each day manure and soiled bedding types were separately collected and transported to compost sites over an eight-day period. Three compositing bins were each hand constructed from wooden pallets with 10 cm slats. The front of the bin was left open for manipulation of materials during the composting process. Initial volumes of the soiled bedding materials were 1m 3 , 1m 3 , and 1.5m 3 for paper, sawdust and straw, respectively. Temperatures were taken for each bedding materials using a 51 cm REOTEMP compost thermometer. Temperatures were taken on Day 0 and every four days over the 65-day trial (n=52). Temperature was used to determine the need for moisture addition and aerating by turning to keep the piles microbially active. On Day 37 the C:N ratio was adjusted by the addition of ammonium sulfate, 0.1 kg, 0.1 kg and 0.14 kg for sawdust, phone book paper and straw piles, respectively. Mean standard error and range for compost temperatures (C) were: phone book paper, 33.17±10.33 (13–52); sawdust, 45.6±9.35 (27–58); straw, 30.42±6.57 (16–39). The sawdust composted more readily as compared to the phone book paper or straw. The paper and straw had poorer structure, which caused compaction of the material when moistened; thus, porosity, oxygen supply and microbial activity were reduced.

Summary The physiological effect on the equine respiratory tract of recycled phone book paper vs. sawdust bedding was investigated in 12 mares with no clinical signs of respiratory disease. Mares were housed in a 20-stall barn and randomly assigned to one of two treatment groups (Group 1=sawdust; Group 2=phone book paper) for 14 days. After a 14-day turnout, Group 1 was assigned to phone book paper and Group 2 was assigned to sawdust for 14 days using a crossover experimental design. Endoscopic examinations of the upper respiratory tract and trachea along with tracheal washes (TW) were performed on days 0 and 14 of each trial. Cytologic examinations were performed on TW samples. Cell type and laboratory interpretation of TW samples were noted. There was no difference (P>0.05) in cell type between treatment groups within or across trials. Laboratory interpretation indicated no abnormalities in 30 of 48 TW samples. Stall conditions were visually rated and graded daily for drinking water cleanliness, depth of bedding and absorbency, overall cleanliness, ammonia odor, and aerial ammonia levels. The phone book paper bedding was more absorbent (P

Agricultural crop and animal production systems are important sources and sinks for atmospheric methane (CH4). The major CH4 sources from this sector are ruminant animals, flooded rice fields, animal waste and biomass burning which total about one third of all global emissions. This paper discusses the factors that influence CH4 production and emission from these sources and the aerobic soil sink for atmospheric CH4 and assesses the magnitude of each source. Potential methods of mitigating CH4 emissions from the major sources could lead to improved crop and animal productivity. The global impact of using the mitigation options suggested could potentially decrease agricultural CH4 emissions by about 30%.

Twelve inhibitors of eicosanoid biosynthesis were examined for their ability to affect the response of insect cells in vitro and developing larvae to δ-endotoxin from Bacillus thuringiensis. The response of cultured insect cells from Manduca sexta, Choristoneura fumiferana, and Plodia interpunctella to CryIA(c) and CryIC protein from Bacillus thuringiensis was measured while exposed to various concentrations of specific cyclooxygenase and/or lipoxygenase inhibitors. Five of the inhibitors (curcumin, baicalein, nordihydroguaiaretic acid, indomethacin, and eicosatetraynoic acid) were toxic to the cells at high concentrations (>20 μM). Surprisingly, the same inhibitors had no significant effect upon normal larval development, except for nordihydroguaiaretic acid. No true, consistent difference was detected with either lipoxygenase or cyclooxygenase inhibitors for cells or larvae treated with δ-endotoxin. However, the δ-endotoxin response of insect cells in vitro and developing larvae in the presence of nordihydroguaiaretic acid was strong evidence of an involvement with P450 cytochromes in the B. thuringiensis toxic response.

The River and Flood Program in the National Weather Service, in its mission to save lives and property, has the responsibility to gather hydrologic data from a variety of sources and to assemble the data to make timely and reliable hydrologic forecasts. The intent of this paper, the second in a series of three, is to present an overview of the operational responsibilities of the River and Flood Program: how data are collected, what models-systems are currently in operation to process the data, and how the application of these procedures and techniques are applied in different types of hydrologic forecasting.

This study was designed to quantify plant selection by Angora goats on a sagebrush-bunchgrass rangeland and to provide information as to the potential for using goats to rehabilitate sagebrush rangelands in less than optimal condition. Goats were introduced to sagebrush-steppe rangeland at the Squaw Butte Experimental Range in eastern Oregon. Groups were maintained separately to avoid social learning across groups. Diets were ascertained using focal-animal bite-count observations during five consecutive seasons, summer of 1990 through summer 1991. Does and kids were primarily graminivorous; however, there was strong seasonality in species preference and a significant age difference in diets selected. Kids selected a more diverse diet and consumed significantly higher amounts of sagebrush and other woody plants during the initial observation season. Animal age influenced plant selection throughout the study until kids were 18 months old.

A VLSI implementation of an artificial neural network using a single n-channel MOS (metal-oxide semiconductor) transistor per synapse is investigated. The simplicity of the design is achieved by using pulse width modulation to represent neural activity and by using a novel technique to manipulate negative weights. A simple multilayer perceptron (MLP) network was simulated using the SPICE circuit simulator and the performance of a hardware realization of the same MLP network was measured. Simulations and measurements are shown to agree well. >

E-beam excitation of rare gas and rare gas—oxygen and/or N 2 O mixtures has revealed various prominent emission features. In the case of Ar/O 2 , new emission bands at 185.0 and 204.5 nm have been recorded. Excitation of Kr/O 2 and Kr/N 2 O mixtures leads to a broad continuum and several undulations in the UV. Emission features in XeO have been briefly reexamined. Although no NeO emission bands were observed, Ne emits well into the VUV. The third continuum of Ar at ≈ 191 nm is related at least in part to impurities. In general, the rare gas third continua are not strongly quenched by O 2 .

Summary We have derived model laws that relate experimental parameters of a physical model of hydraulic fracture propagation to the prototype parameters. Correct representation of elastic deformation, fluid friction, crack propagation, and fluid leakoff forms the basis of the scaling laws. For tests at in-situ stress, high fluid viscosity and low fracture toughness are required. Tests on cement blocks agreed with the scale laws based on elastic behavior.

This study was part of a broad search for endogenous regulators of L-type calcium channels. The screening for active fractions was done by measuring inhibition [3H]1,4-dihydropyridine (DHP) binding to rat cardiac and cortex membranes. An inhibitory fraction, termed lyophilized brain hexane-extractable inhibitor (LBHI), was isolated from hexane extracts of lyophilized calf brain. The active substance was purified by a series of chromatographic steps. 13C nuclear magnetic resonance (NMR), 1H coherence spectroscopy (COSY) NMR and fast atom bombardment (FAB) mass spectroscopy suggested that LBHI was N-arachidonic acid-2-hydroxyethylamide. Synthesis of this substance and subsequent high performance liquid chromatography (HPLC) and NMR analysis confirmed this structure. Synthetic LBHI (SLBHI) inhibited [3H]DHP binding to rat cortex membranes with an IC50 value of congruent to 15 microM and a Hill coefficient of congruent to 2. Saturation analysis in the presence of SLBHI showed a change in KD (equilibrium dissociation constant), but not maximal binding capacity (Bmax). SLBHI produced an increased dissociation rate, which, along with the Hill slope of1, suggested a non-competitive interaction with the DHP binding site. The results suggest that arachidonic acid derivatives may be endogenous modifiers of the DHP calcium antagonist binding site.

Poor quality diets of ruminant farm animals in developing countries lead to relatively large emissions of methane (a gas implicated in global climate change) per unit of useful animal product. Production of high quality feed requires intensive agronomic practices that result in increased emission of carbon dioxide and nitrous oxide, which also contribute to global climate change. Focusing on India, we estimate that improved diets could reduce by one-third greenhouse gas production (expressed as CO2 equivalents) per kg of milk. On the other hand, replacement of bullocks with tractors is projected to result in a greater than two-fold increase in CO2 equivalents.

Methane emissions were measured during manure incubations in the laboratory simulating field depositions and by placing enclosures over feedlot sites. Results indicate a great deal of variation in manure methane production, both under feedlot conditions and under simulated grazing conditions. The variables which contributed most to the differences in methane production were temperature, moisture and diet of the animal. Incubation loss rates were 7% or less of potential manure degradation loss when manure was kept wet and less than 1% of total potential loss when the manure was allowed to dry. Emissions from feedlot accumulations extrapolated to the whole feedlot commonly ranged from .1 to .2% of the potential of only one day's manure. We conclude that only anaerobic lagoon disposal is likely to produce significant methane emissions from livestock manure. Given the stated assumptions, beef cattle in the U.S. are estimated to produce approximately 0.2 million tons of methane and dairy cattle manure .4 million tons, which is approximately 2% of potential for beef cattle and 10% of potential for dairy cattle. The total equates to approximately 11% of that produced directly by cattle annually.

A pulsed power supply is being designed to deliver 5 MJ at 1 MA at 1 shot per second to a railgun. The supply stores energy at low current in the primary of a hydrogen-cooled transformer. A switch opens the primary circuit to transfer energy to the secondary, stepping the current up to 1 MA. The relationship between the transformer and switch is being studied to determine how the total power supply mass can be minimized. Vacuum interrupters and gate-turn-off (GTO) thyristors are used in the switch. Switch mass dominates the system, accounting for 85% of the total mass. The switch must absorb the uncoupled energy of the transformer. Low transformer coupling requires large capacitors. Even with high coupling, capacitors account for 75 to 85% of the switch mass. If transformer coupling increases, the uncoupled energy decreases, resulting in lower capacitor mass. At high transformer coupling, switch mass also depends on the turns ratio of the transformer. At lower turns ratio, a lower voltage is placed across the switch capacitors. Lighter capacitors can be used, reducing system mass. The combined transformer and switch (system) mass is minimized when transformer coupling is 0.97 to 0.99 and the turns ratio is as low as possible. >

Two possible switches topologies used to switch the primary of an energy storage transformer are compared. A series-connected semiconductor/vacuum interrupter switch and an all-solid-state switch are sized for a 5 MJ energy storage transformer. Gate-turn-off (GTO) thyristors are used as the semiconductor switches. Total mass estimates, operating characteristics, and applicability to a space-based pulsed power system are discussed. Both designs store the commutation energy in capacitors. The communication energy is then dissipated in resistors after switching has occurred. The capacitor mass is shown to dominate the total switch mass. Therefore, the mass of both switches is approximately equal. The advantages of the all-solid-state switch include high reliability, no moving parts, proven design, and a high probability of future mass reduction with new semiconductor device developments. The all-solid-state switch has a higher on-state power dissipation than the vacuum interpreter switch. it is suggested that the advantages of the all-solid-state switch outweigh the disadvantages of the higher power dissipation. >

This paper describes NSF-supported work in parallelized computer system simulators being done in the Electrical and Computer Engineering Department at the University of Texas at Austin. Our work is currently following two paths: (i) the FAST simulation methodology[9, 11, 10] that is capable of simulating complex systems accurately and quickly (currently about 1.2MIPS executing the x86 ISA, modeling an out-of-order superscalar processor and booting Windows XP and Linux) and (ii) the RAMP-White (White)[l, 22] platform that will soon be capable of simulating very large systems of around 1000 cores. We plan to combine the projects to provide fast and accurate simulation of multicore systems.

An attempt was made to overcome incomplete starch digestion in the small intestine of ruminants by exogenous amylase and/or sodium bicarbonate additions into the small intestine of steers fed on a diet of 60% cracked maize grain and 30% maize silage. Four Hereford × Angus steers were cannulated in the rumen, duodenum, jejunum and ileum. Ytterbium-marked maize was given daily and a liquid phase marker, Cr-EDTA, was infused into the rumen continuously. Treatments (amylase, bicarbonate, amylase plus bicarbonate or distilled water) were individually infused into the jejunal cannula at an average rate of 190 ml day−1 for four 7-day periods in a 4 × 4 Latin square design. Duodenal and ileal composite samples were analyzed for dry matter (DM), starch and marker contents to determine ruminal and small intestinal digestibility. Digesta kinetics for the small intestine indicated that the particulate and liquid phases flowed together with little separation. The pH of the duodenal, jejunal and ileal digesta prior to any treatment infusions averaged 2.5, 4.8 and 7.3, respectively. Starch flow to the small intestine averaged 1000 g day−1 with 350 g passing to the large intestine. Nutrient digestibility was not affected by the infusion treatments. The results were interpreted to suggest that amylase and probably digesta pH are not the first limiting factors in the digestion of maize starch in the small intestine of cattle adapted to starch diets.

The effect of pretreatment with medicated feed on ({sup 14}C) salinomycin residue levels in pig tissues was studied. Pigs were fed unmedicated feed or feed medicated with salinomycin at 41 ppm in the diet for 29 days and then dosed with ({sup 14}C)salinomycin for 8 days. Total drug residue levels were below quantifiable limits of detection of kidney, fat, and muscle but at the tolerance limit of 1,800 ppb for liver. In liver, pretreatment tended to lower total residue levels, and unchanged ({sup 14}C)salinomycin accounted for

We are writing this letter to express our interest in pursuing an experiment at Fermilab to search for neutrinoless conversion of muons into electrons in the field of a nucleus, which is a lepton flavor-violating (LFV) reaction. The sensitivity goal of this experiment, improving on existing limits for this process by more than a factor of 10000, is very similar to that of previous experiments that have been proposed but never built. It would provide the most sensitive test of LFV, a unique and essential window on new physics unavailable at the high energy frontier. We present a conceptual scheme that would exploit the existing Accumulator and Debuncher rings to generate the required characteristics of the primary proton beam. The proposal requires only modest modifications to the accelerator complex after including those already planned for the NOvA experiment, with which this experiment would be fully compatible. The search for lepton flavor violation (LFV) has long played an important role in the evolution of our understanding of electroweak interactions. The neutrinoless conversion of a muon to an electron in the field of a nucleus is a particularly interesting example of an LFV process involving charged leptons. In the Standard Model, such conversions would take place via loop diagrams involving virtual neutrino mixing, at a rate far below the threshold of any currently conceivable experiment. Indeed, any detectable signal would be a definite indication, albeit indirect, of new dynamics at multi-TeV energy scales. Enhanced rate for this process is an almost universal feature of beyond the Standard Model physics, and the fact that such a process has not been observed has constrained or eliminated many models [1]. While it is widely believed that new physics will appear at LHC energies, the LHC is not well-equipped to study LFV directly. An often-quoted example is in the case of supersymmetry. The LHC will probe slepton masses, but it cannot compete with muon decay experiments in constraining the slepton mixing angles. Sensitive searches for rare or forbidden leptonic and semi-leptonic LFV processes, especially those involving charged leptons, are essential for the comprehensive characterization of new high energy physics. While there are several potential reactions that can be used to probe LFV, muon to electron conversion has the remarkable feature that it does not require the coincidence of two final-state particles. The spectacular signature is a single conversion electron of well-defined energy, separated from most of the sources of background. As a result, very high muon data rates can be handled and an unusually sensitive search for LFV becomes feasible. Indeed, at the level of sensitivity discussed below, a large class of supersymmetric models would predict 100's of conversion events. Additionally, compositeness and Z{prime} models would be probed at the multi-TeV scale in a manner complementary to direct LHC searches. Lepto-quarks would be probed at the 3000 TeV scale. Muon to electron conversion is therefore sensitive to many new physics scenarios at energy scales that cannot be probed by direct searches using other foreseeable accelerators.

An 8 GeV superconducting linear accelerator (SCL) has been proposed [1] as a single stage H- injector into the Main Injector (MI) synchrotron . This would be the highest energy H- multi-turn injection system in the world. The conceptual design of an injection system has been further refined by addressing transverse phase space painting issues, chicane dipole fields and foil location, foil temperature issues, and initial longitudinal phase space painting simulations. We present the current state of design.

An 8 GeV superconducting linear accelerator (SCL) has been proposed as a single stage H- injector into the Main Injector (MI) synchrotron[1]. This would be the highest energy H- multi-turn injection system in the world. An injection absorber is required to absorb a few percent o the incoming beam on a regular pulse by pulse basis. The requirements and conceptual design of an internal absorber, capable of steady state 6.5 kW is discussed.

During the design of the Fermilab Main Injector synchrotron it was recognized that the aperture was limited at the beam transfer and extraction points by the combination of the Lambertson magnets and the reused Main Ring quadrupoles located between the Lambertsons. Increased intensity demands on the Main Injector from antiproton production for the collider program, slow spill to the meson fixed target program, and high intensity beam to the high energy neutrino program have led us to replace the aperture-limiting quadrupoles with newly built magnets that have the same physical length but a larger aperture. The magnets run on the main quadrupole bus, and must therefore have the same excitation profile as the magnets they replaced. We present here the design of the magnets, their magnetic performance, and the accelerator performance.

Upon the termination of the Fermilab Collider program, the current Recycler anti-proton storage ring will be converted to a proton pre-injector for the Main Injector synchrotron. This is scheduled to increase the beam power for the 120 GeV Neutrino program to upwards of 700 KW. Due to momentum aperture requirements, a Recycler to Main Injector transport line will be constructed wholly within a horizontal dispersion free region in the 30 straight section. The concept design will be presented in this paper.

High intensity operation of the Fermilab Main Injector has resulted in increased activation of machine components. Efforts to permit operation at high power include creation of collimation systems to localize losses away from locations which require maintenance. As a first step, a collimation system to remove halo from the incoming beam was installed in the Spring 2006 Facility Shutdown [1]. We report on commissioning studies and operational experience including observations of Booster beam properties, effects on Main Injector loss and activation, and operational results.

Upon the termination of the Fermilab Collider program, the current Recycler anti-proton storage ring (RR) will be converted to a proton pre-injector for the Main Injector (MI) synchrotron. This is scheduled to increase the beam power for the 120 GeV Neutrino program to upwards of 700 KW. A transport line that can provide direct injection from the Booster to the Recycler while preserving direct injection from the Booster into the Main Injector and the 8 GeV Booster Neutrino program will be discussed, and its concept design will be presented.

Results of modeling with the 3-D STRUCT and MARS 15 codes of beam loss localization and related radiation effects are presented for the slipstacking injection to the Fermilab Main Injector. Simulations of proton beam loss are done using multi-turn tracking with realistic accelerator apertures, nonlinear fields in the accelerator magnets and time function of the RF manipulations to explain the results of beam loss measurements. The collimation system consists of one primary and four secondary collimators. It intercepts a beam power of 1.6 kW at a scraping rate of 5% of 5.5E+13 ppp, with a beam loss rate in the ring outside the collimation region of 1 W/m or less. Based on thorough energy deposition and radiation modeling, a corresponding collimator design was developed that satisfies all the radiation and engineering constraints.

To maximize the tune space due to momentum spread, an operating point close to the coupling resonance line is desirable. This requires a knowledge of all the coupling sources in the Recycler and a correction system capable of global decoupling to the desired level. We report on the efforts to identify major sources of coupling and verification of the integrity of the powered skew quad circuits used for global decoupling

SYNOPSIS Many elastomer products come to the end of their useful life through abrasive wear (wear brought about through local or general sliding); however the processes of abrasive wear are complex and challenging. Approaches towards improved understanding and prediction of abrasive wear under various conditions are outlined. The most fully developed class of model is that originated by Southern & Thomas (1978) who consider abrasion under conditions of moderate-to-high tangential contact stress; they envisage abrasion progressing by fatigue crack growth at the roots of macroscopic flaps or “tongues” of rubber. The Southern & Thomas model fits some experimental observations but not others. The roles of temperature, oxygen and mechano-chemical effects are discussed (Gent & Pulford, 1983). Experiments are described in which five materials [based on natural rubber (NR), acrylonitrile butadiene (NBR) and ethylenepropylenediene (EPDM)] were abraded with a (blunt) “blade”. Evolving visual patterns and patterns of blade abrader force were monitored as was material loss. Similarities between the visual wavy (Schallamach) patterns, often associated with rapid wear, and the force patterns suggest a close relationship between the two. The fact that force patterns, of a wavelength which persists, are discernable from the start of scraping suggests that aspects of the Schallamach pattern have their origin in non-destructive abrader-elastomer interactions. For unidirectional abrasion the wear rates observed under similar conditions and for elastomeric materials of similar hardness varied widely – NR at 55 International Rubber Hardness Degress (IRHD) giving 60 times the wear rate of 55 IRHD EPDM – for which no Schallamach pattern was observed. In bidirectional abrasion, wear rates were generally a little lower than under unidirectional conditions but the reduction was rather minor. Although there has been considerable progress made, a comprehensive quantitative theory of abrasion of rubbery materials is still to be developed.

The objective of this study was to determine the effect of emptying the rumen on the heat production of wethers. Gaseous energy losses were measured with eight wethers (average BW 72 kg) fed two basal diets with or without a distal ileum gum infusion. Animal gas exchanges were determined over two consecutive days to obtain baseline values, and also after emptying the rumens and measuring animal gas exchanges during approx. 2.5 h. Heat production after emptying the rumen decreased approx. 50%, to values similar to what would be expected during fasting heat production. Respiratory quotients decreased from around 1.0 to 0.83, indicating a drastic increase in fat utilization. Results indicate that energy expenditure from metabolizing substrates prior to or after absorption from the rumen accounted for around 50% of total heat production in this experiment, and that animals were able to change from a postpandrial state to starvation in minutes.

In the commissioning of the Fermilab Recycler ring the need for higher order corrector magnets in the regions near beam transfer lines was discovered. Three types of permanent magnet skew quadrupoles, and two types of permanent magnet sextupoles were designed and built. This paper describes the need for these magnets, the design, assembly, and magnetic measurements.

The Recycler Ring, an 8 GeV antiproton accumulator, is being commissioned at Fermilab. Antiproton transfers in and out of the Recycler Ring take place through two transfer lines connecting the Recycler to the Main Injector. Transfer line layout and operation of beam transfers will be described. Particular attention has been paid to injection mismatch effects, in order to limit emittance growth during transfers. A considerable improvement has been achieved by removing vacuum windows, previously present in both transfer lines.

Round-trip beam transfers between the Fermilab Main Injector and Recycler (antiproton accumulator) have been plagued by an emittance dilution of about a factor of 2 with corresponding beam loss. The source of the large dilution was traced to two Ti vacuum windows, one installed in each of the two transfer lines that connect the machines for beam injection/extraction. The dilution can be accounted for by calculating the increase in beam divergence due to multiple scattering in the windows followed by an amplitude mismatch that serves to further enhance the instantaneous dilution immediately downstream of the window. This work presents the analytical basis for the phase-space, or emittance, dilution due to the window, the subsequent optics mismatch, and then presents an analysis of beamline measurements that evidences the effect and validates the analytical argument. The data showed a strong skew quadrupole component in the transfer line optics that initially complicated the analysis, but was effectively eliminated in some of the data samples acquired under specific beam conditions.

The performance, in-system reprogrammability, flexibility, and reduced costs of SRAM-based FPGAs make them very interesting for high-speed, on-orbit data processing, but, because the current generation of radiation-tolerant SRAM-based FPGAs are derived directly from COTS versions of the chips, several issues must be dealt with for space, including SEU sensitivities, power consumption, thermal problems, and support logic. This paper will discuss Los Alamos National Laboratory's approach to using the Xilinx XQVR1000 FPGAs for on-orbit processing in the Cibola Flight Experiment (CFE) as well as the possibilities and challenges of using newer, system-on-a-reprogrammable-chip FPGAs, such as Virtex I1 Pro, in space-based reconfigurable computing. The reconfigurable computing payload for CFE includes three processing boards, each having three radiation-tolerant Xilinx XQVRl 000 FPGAs. The reconfigurable computing architecture for this project is intended for in-flight, real-time processing of two radio fi-equency channels, each producing 12-bit samples at 100 million samples/second. In this system, SEU disruptions in data path operations can be tolerated while disruptions in the control path are much less tolerable. With this system in mind, LANL has developed an SEU management scheme with strategies for handling upsets in all of the FPGA resources known to be sensitive to radiation-induced SEUs. While mitigation schemes for many resources will be discussed, the paper will concentrate on SEU management strategies and tools developed at LANL for the configuration bitstream and 'half latches'. To understand the behavior of specific designs under SEUs in the configuration bitstream, LANL and Brigham Young University have developed an SEU simulator using ISI's SLAACl-V reconfigurable computing board. The simulator can inject single-bit upsets into a design's configuration bitstream to simulate SEUs and observe how these simulated SEUs affect the design's operation. Using fast partial configuration, the simulator can cover the entire bitstream of a Xilinx XQVRl 000 FPGA, which has 6 million configuration bits, in about 30 minutes. Instead of using a combination of TMR and configuration scrubbing for bitstream SEU mitigation, the approach developed for CFE uses minimal logic redundancy along with an SEU detection and correction scheme to handle bitstream SEUs. Though this approach allows some SEUs to affect less critical user logic, it requires considerably fewer FPGA resources than TMR and allows bitstream SEU rates to be monitored. 'Half latches', another class of SEU sensitive FPGA state elements, are used to provide logic constants in user FPGA designs but are not explicitly controlled by the configuration bitstream. Upsets in half latches cannot be detected by readback nor corrected via configuration repair or scrubbing - only a full reconfiguration can reliably restore their state. We have created a tool, called RadDRC, which can replace all critical half latches with more visible and correctable constant sources. Lastly, in looking forward, this paper will briefly consider the possible benefits and risks of using reconfigurable system-on-a-chip FPGAs, such as the Virtex II Pro, for reconfigurable computing in space. The paper concludes with a summary of challenges for using reconfigurable computing in space and a summary of future research at LANL in this area.

We describe methods used to measure and control tunes in the Fermilab Main Injector (FMI). Emphasis is given to software implementation of the operator interface, to the front-end embedded computer system, and handling of hysteresis of main dipole and quadrupole magnets. Techniques are developed to permit control of tune of the Main Injector through several acceleration cycles: from 8.9 GeV/c to 120 GeV/c, from 8.9 GeV/c to 150 GeV/c, and from 150 GeV/c to 8.9 GeV/c. Systems which automate the complex interactions between tune measurement and the variety of ramping options are described. Some results of tune measurements and their comparison with the design model are presented.

Chromaticity control in the Fermilab Main Injector will be important both in accelerating protons and antiprotons from 8 GeV to 150 GeV (or 120 GeV) and in decelerating recycled 150 GeV antiprotons to 8 GeV for storage in the Recycler Ring. The Main Injector has two families of sextupoles to control the chromaticity. In addition to the natural chromaticity, they must correct for sextupole fields from ramp-rate-dependent eddy currents in the dipole beam pipes and current-dependent sextupole fields in the dipole magnets. The horizontal sextupole family is required to operate in a bipolar mode below the transition energy of 20 GeV. We describe methods used to control chromaticities in the Fermilab Main Injector. Emphasis is given to the software implementation of the operator interface to the front-end ramp controllers. Results of chromaticity measurements and their comparison with the design model will be presented.

A discussion of electron probe X-ray microanalysis (EPMA) is presented. Methods used to generate EPMA images are given. Applications of EPMA to muscle and secretory cells are presented. >

The colliding beams in the SSC (Superconducting Super Collider) must cross at a small angle, so that when the bunches pass each other away from the interaction point (IP), they are sufficiently separated to avoid disruptive beam beam forces. However, the crossing angle is so small that the adjacent quadrupoles must be common to both beams. Only after passing through four common quadrupoles on each side of the IP are the beams split by vertical dipoles into separate beamlines. In order to make the closed orbits of the two beams cross at a definite angle at the IP (within a range up to 150 mu rad), a series of correction dipoles is placed in the insertions. If these dipoles are excited in such a way as to control the closed orbits alone, the dispersion will be mismatched, reaching values of up to 50 cm in the arcs. This mismatch is due to the closed-orbit displacements in the interaction region quadrupoles, causing them to act as bending magnets. Therefore, the closed orbit and dispersion must be matched simultaneously. Solutions to this problem are presented. >

Results of the continuing analysis of the nonlinear dynamics experiment, E778, are presented. Sixteen special sextupoles introduced nonlinearities in the Tevatron. Smear, which is one of the parameters used to quantify the degree of nonlinearity, was extracted from the data and compared with calculation. Injection efficiency in the presence of nonlinearities was studied. Measurements of the dynamic aperture were performed. The final results in one degree of freedom of the smear, the injection efficiency, and the dynamic aperture are presented. Particles captured on nonlinear resonance islands were directly observed and measurements were taken. The capture efficiency was extracted from the data and compared with prediction. The influence of tune modulation on the stability of these islands was investigated. Plans for future measurements are discussed. >

The time behavior of the sextupole component of the Tevatron superconducting dipoles under ramping conditions was studied. Large time-dependent sextupole corrections are necessary to maintain constant chromaticities in the Tevatron. The authors discuss the implementation and results of these corrections in terms of emittance growth and intensity loss during the Tevatron ramp. >

The Tevatron lattice has regions of nonzero dispersion which influence the beam size at the crossings locations. During six-on-six collider operation, each pbar bunch sees 12 crossings per revolution, producing large tune shifts. Estimates of linear beam-beam tune shift are given for various Tevatron lattices. These estimates are compared with those using the round beam approximation (RBA). Comparison between predictions and measured pbar tunes is made. For the Tevatron lattices studied (using typical beam emittances) the RBA always overpredicts the linear calculation. SYNCH calculations using nonlinear lenses due to the beam-beam interaction agree with the linear calculations. The dynamic beta effect is small for the injection cogged fixed target lattice. The results of the cogging experiment seem to agree in sign and order of magnitude with the predictions of the linear tune shift calculations. >

New low- beta insertions will be used in the Tevatron collider at both the B0 and D0 interaction regions. To reduce the beam-beam tune shift, electrostatic separators will be installed to separate the beams horizontally and vertically at all but the two interaction points. An insertion has been installed at the B0 straight section and enough separators to create collisions at B0 only. The initial beam tests using these devices are described. The procedures for tuning of the insertion and separators are described. Also discussed is the procedure to change the lattice from the injection lattice to the 50-cm beta lattice used in high energy physics. >

Results of a study made to evaluate the coil-winding aperture needed for the final booster in the injector chain for the SSC (Superconducting Super Collider) are presented. Lattice designs based on 5-cm and 7-cm dipole apertures are evaluated by looking at the long-term dynamic aperture, at injection and the good-field aperture requirement for resonant extraction of high-energy test beams. The 5-cm dipole is found to be marginal, while the 7-cm dipole satisfies field quality criteria for both injection and extraction. >

A description of the design and operation of the High Energy Booster is presented. This includes an overview of the general geometry of the ring followed by details of the various lattice components. Aspects of the injection, abort, extraction, and resonant extraction processes are presented. The RF system and some plans for the operational cycles are also given. >