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Background There is significant data in the medical and surgical literature supporting the correlations between positive volume balance and negative outcomes such as AKI, prolonged mechanical ventilation, intensive care unit and hospital length of stay and increased mortality. Methods This single-center, retrospective chart review included adult patients identified from a Trauma Registry database. The primary outcome was the total ICU LOS. Secondary outcomes include hospital LOS, ventilator-free days, incidence of compartment syndrome, acute respiratory distress syndrome (ARDS), renal replacement therapy (RRT), and days of vasopressor therapy. Results In general, baseline characteristics were similar between groups with the exception of mechanism of injury, FAST exam, and disposition from the ED. The ICU LOS was shortest in the negative fluid balance and longest in the positive fluid balance group (4 days vs 6 days, P = .001). Hospital LOS was also shorter in the negative balance group than that of the positive balance group (7 days vs 12 days, P < .001). More patients in the positive balance group experienced acute respiratory distress syndrome compared to the negative balance group (6.3% vs 0%, P = .004). There was no significant difference in the incidence of renal replacement therapy, days of vasopressor therapy, or ventilator-free days. Discussion A negative fluid balance at seventy-two hours was associated with a shorter ICU and hospital LOS in critically ill trauma patients. Our observed correlation between positive volume balance and total ICU days merits further exploration with prospective, comparative studies of lower volume resuscitation to key physiologic endpoints compared with routine standard of care.

This paper presents a nested hydrodynamic model of the Fish River, a tributary of the sub-estuary Weeks Bay located in Mobile Bay, Alabama. The Environmental Fluid Dynamics Code (EFDC) and a novel dynamic-coupling tool were used to link three EFDC hydrodynamic models corresponding to Mobile Bay, Weeks Bay, and the Fish River. The dynamically-coupled models were used to simulate inundation scenarios for combinations of 2-, 7.5-, 10-, 25-, and 100-year floods, and the hurricane surge that occurred during hurricane Katrina. The nested and dynamically-coupled model was developed using available public-access bathymetry and topography databases (National Elevation Dataset, and NOAA bathymetry), and run without recurring to calibration techniques. The simulation of combined scenarios showed that inundated areas increase from 0.07 % up to 189 % with respect to the actual flood that took place during the Katrina event (Katrina + 1-year flood). The results suggest that increases in inundated area are relatively much higher from a 1-year flood to a 7.5 year-flood (128 % flooded area increase) than for higher return periods. For the 25-year and the 100-year floods, inundated areas almost triple from the area corresponding to the base-case (Katrina event), with percent increases of 182 % and 189 % respectively.

An efficient synthesis of a single conjugate of gentamicin is described. Reaction of the primarily three component gentamicin complex with excess benzyl chloroformate provided a mixture of the amine-protected components which were separable at scale by preparative HPLC using UV detection. Mild deprotection provided the pure separated components. Conjugation of one deprotected component permitted preparation of a single, manufacturable gentamicin conjugate. These strategies provide a general method for the separation of gentamicin components as well as a useful solution for the regiospecific synthesis of gentamicin conjugates.

The focus of this presentation is on the use of SUEX epoxy Thick Dry Film Sheets (TDFS) as a photoimagable dielectric layer in fan-in, fan-out and e-WLP applications. The sheets can be laminated over severe topography from under 2 μm to over 200 μm in height yielding void free coatings with 100% planarization over the entire substrate. The TDFS are available in a range of thicknesses and wafer or panel sizes. This new material is prepared under a highly controlled solvent-less process, which provides uniform coatings between two throw-away layers of protective polyester film. SUEX sheets of 100 μm thickness have been vacuum laminated in an isothermal process at 60–80°C over 180 μm high, 2mm X 2mm device chips mounted onto a silicon carrier wafer. Process optimization studies were run to determine the desired chamber vacuum, chuck temperature, lamination pressure and lamination time for optimal performance. The entire lamination process has a cycle time of about 10min. Using a vacuum laminator we have been able to obtain totally void-free coatings over 2 to 5 μm high bonding pads and buss lines at the silicon surface with a resist thickness of 205 μm over the trench and 25 μm thickness over the back of the chip with 100% planarization over the surface interface. Exposures on a contact aligner have yielded nominal 50 μm diameter via holes through the resist film to the contact pads at the bottom of the trench. Excellent adhesion to all surfaces on both the carrier wafer and the device chip has been obtained without any delamination or crack formation. Additional work to be presented will demonstrate the filling of the vias with electroplated copper to form interconnects the interconnects to for connection to bonding pads on the fan-out package surface.

NASA Glenn Research Center (GRC) has recently demonstrated a polymer electrolyte membrane (PEM) based regenerative fuel cell system (RFCS) that operated for five contiguous back-to-back 24h charge/discharge cycles over a period of 120h. The system operated continuously at full rated power with no significant reactant loss, breakdowns, or degradations from June 26 through July 1, 2005. It demonstrated a closed-loop solar energy storage system over repeated day/night cycles that absorbed solar electrical power profiles of 0–15kWe and stored the energy as pressurized hydrogen and oxygen gas in charge mode, then delivered steady 4.5–5kWe electrical power with product water during discharge mode. Fuel cell efficiency, electrolyzer efficiency, as well as system round-trip efficiency were determined. Individual cell performance and the spread of cell voltages within the electrochemical stacks were documented. The amount of waste heat dissipated from the RFCS was also reported. The RFCS demonstrated fully closed-cycle operation without venting or purging, thereby conserving reactant masses involved in the electrochemical processes. Smooth transitions between the fuel cell mode and electrolyzer mode were repeatedly accomplished. The RFCS is applicable to NASA’s lunar and planetary surface solar power needs, providing lightweight energy storage for any multikilowatt-electrical application, where an environmentally sealed system is required.

MicroChem Corp. and Nippon Kayaku Co., Ltd. have jointly developed a new, photoimageable coating composition for use in fabricating a wide variety of micro-electromechanical systems (MEMS) and optical MEMS. This chemically amplified thick-film photoresist, known as KMPR, has many of the same high-aspect ratio photo imaging properties as solvent developable SU-8, but can be developed in a conventional aqueous alkaline developer (TMAH) and readily stripped from the wafer.Single-factor experimental methods rarely find the optimum performance of a photoimageable coating efficiently and often fail to detect the interactions so common in complicated photochemical systems. By combining the settings of several factors simultaneously in an array (experimental design), it is possible to separate out the main effects and their interactions.1This paper presents the optimization of KMPR for contact alignment and near diffraction-limited, thick film reduction stepper applications. A Sequence of Taguchi style, half-factorial experimental designs was used to evaluate the process parameters for a 5 and 50 Mm thick film exposed on a contact aligner followed by a third half-factorial design for a 10 Mm thick film of KMPR photoresist exposed on a 365 nm, 0.40 N.A. stepper. Independent factors, such as: soft bake time, focus, exposure dose, initiator activation time (post-exposure bake time), developer time and delay time were evaluated

The closed-cycle hydrogen-oxygen PEM regenerative fuel cell (RFC) at Nasa Glenn Research Center has successfully demonstrated closed-cycle operation at rated power for multiple charge/discharge cycles. During the charge cycle the RFC has absorbed input electrical power simulating a solar day cycle ranging from zero to 15 kWe peak, and delivered steady 5 kWe output power for periods exceeding 8 h. Orderly transitions from charge to discharge mode, and return to charging after full discharge, have been accomplished without incident. The RFC is beginning to demonstrate its potential as an energy storage device for aerospace solar power systems such as solar electric aircraft, lunar and planetary surface installations – any airless environment where minimum system weight is critical. This hardware demonstration is supplemented by a thermodynamic and mass/volume modeling effort aimed at characterizing RFC systems and determining their optimum design and operation.

A dynamic-coupling tool designed to link several hydrodynamic models is presented. The tool is able to dynamically transfer time-series data among models that are geographically adjacent. Dynamic data transfer is implemented at the models’ common boundaries. The Message Passing Interface (MPI) and a coupling code were used for implementing the dynamic link. Several issues that had to be overcome during the development of the tool (such as porting of the code to a Linux environment, MPI implementation, and compiler flags used for optimum performance) are discussed. The tool is applied to a test case in which three hydrodynamic models built with the Environmental and Fluid Dynamics Code (EFDC) are run with the dynamic-coupling tool in a Linux cluster. Run times were compared to a sequential run of the three models in a Windows environment. A speed up of 8.53 was achieved by exploring and finding an optimal combination of Intel Fortran compiler flags.

The focus of this paper is on the use of SUEX Thick Dry Film Sheet (TDFS) laminates which DJ DevCorp is developing as a thick resist material in optical and X-ray lithography. Preliminary thick dry film sheets up to 1mm thickness were successfully prepared and patterned at the CAMD X-ray beamlines and presented at HARMST 2007. Recently, new results have been published using SUEX resist sheets in UV lithography showing great market potential including plating molds for metal microparts, polymer MEMS, multilayer microfluidics structures, BioMEMS, medical devices, wafer level packaging processes, and displays. The SUEX TDFS are available in a range of thicknesses from 100μm to 1mm or more and are pre-cut into a number of standard wafer sizes. This new material is a modified epoxy formulation containing an antimony-free photo acid generator (PAG) prepared under a highly controlled solvent-less process which provides uniform coatings between two throw-away layers of protective polyester film. As part of our initial studies resist layers of 250, 500 and 1000μm were laminated onto regular silicon wafers using a hot roll laminator at a speed of 1ft/min at 75°C. The entire substrate preparation takes about 1 hour and with practice users can prepare up to 10 substrates in this time which are typically ready to use within 2 hours. In our efforts to develop a commercially viable product we have conducted experiments using standard equipment available at CAMD (Quintel UV aligner and CAMD XRLM 1 and 4 beamline). Initial X-ray exposure tests were done with a bottom dose ranging between 100 and 400 J/cm3 and a top/bottom dose ratio of less than 3 for sheets up to 2mm in thickness. Exposure time for typical conditions of the CAMD storage ring (ring current ranging between 100 and 160mA, beam lifetime of about 10hrs at 100mA ring current) is about 10-15min for a 4' wafer. After exposure the samples were immediately post exposure baked between 70°C and 110°C using a convection oven, taken out and cooled to RT then relaxed up to 3 days before development to reduce stress. Development was done in PGMEA for up to 3 hours for the 1000μm thick samples followed by a short IPA rinse and drying in air. Very high aspect ratios of 100 or more have been routinely patterned with nearly perfectly straight sidewalls (~1-1.5μm deviation for a 1mm tall structure) and excellent image fidelity.

At present one of the most promising production-worthy 193nm resist approaches is a single layer, dry developed, surface imaging, silylation process. An evaluation of commercially available developmental resists shows excellent process versatility and lithographic performance. An evaluation of silylation conditions shows more versatility than previously demonstrated. No flow is seen in silylated features, leading to excellent dimensional control and edge profiles. Preliminary results indicate better than 0.18μm resolution and linearity to 0.20μm without the use of phase shift masks. Geometries of 0.1μm have been demonstrated in a resist process which is available for evaluation of 0.20μm devices processes as well as 256MB DRAM circuits.

This paper reports on the evaluation of XP SU-8 4000NPG for potential use in nanoimprint applications using hot UV imprint lithography. The use of this material is advantageous in that it can be imprinted, exposed and sufficiently cured all at the same temperature without any temperature cycling providing an isothermal process leading to short cycle times. Uncured XP SU-8 4000NPG has a Tg below 10oC, yet its films are sufficiently robust to be handled at temperatures from 40 to 70oC. This resist exhibits excellent flow properties in this temperature range, which is also a range where the post exposure bake of the exposed areas is sufficient to lock in the imprinted patterns and allow easy stamp removal. Wafers can be spin coated with the 4000NPG to provide films of less than 100nm thickness to more than 500 nm and subsequently baked to remove the residual coating solvent. Precoated wafers are introduced into the imprint tool and placed on a pre-heated chuck for a few seconds to reach the set temperature, and then the imprint stamp is applied under pressure for 30-60 sec to allow adequate time to properly fill the mold. While still in the mold, the resist is exposed through the transparent stamp and simultaneously cured for as little as 10 sec in order to remove the stamp without tearing or pattern deformation. The wafer can then be immediately removed from the imprint tool. The optimal temperature is a balance between resist flow, cure rate and the thermal stresses imparted into the cured film at the higher operating temperatures.

Southwest Research Institute conducted a test program on the 26-inch diameter hatch seal o-ring for a manned submersible vehicle. The tests measured o-ring extrusion at pressure differentials across the seal of up to 1560 psig and gaps between the sealing surfaces of up to 0.110 inches. This paper presents a test protocol for determining the maximum gap that a given size o-ring can seal at a given pressure. This paper also presents charts of extrusion vs. seal gap and addresses the potential for o-ring damage when the sealed joint is depressurized. The test results were used in the design of the hatch seal for the U.S. Navy Pressurized Rescue Module and represent the first industry-wide o-ring design data for face seals in large diameter mechanical joints that do not close with pressure.

This paper describes performance characterization tests of a 64 cell hydrogen oxygen PEM fuel cell stack at NASA Glenn Research Center in February 2003. The tests were part of NASA's ongoing effort to develop a regenerative fuel cell for aerospace energy storage applications. The purpose of the tests was to verify capability of this stack to operate within a regenerative fuel cell, and to compare performance with earlier test results recorded by the stack developer. Test results obtained include polarization performance of the stack at 50 and 100 psig system pressure, and a steady state endurance run at 100 psig. A maximum power output of 4.8 kWe was observed during polarization runs, and the stack sustained a steady power output of 4.0 kWe during the endurance run. The performance data obtained from these tests compare reasonably close to the stack developer's results although some additional spread between best to worst performing cell voltages was observed. Throughout the tests, the stack demonstrated the consistent performance and repeatable behavior required for regenerative fuel cell operation.

The regenerative fuel cell development effort at Glenn Research Center (GRC) involves the integration of a dedicated fuel cell and electrolyzer into an energy storage system test rig. The test rig consists of a fuel cell stack, an electrolysis stack, cooling pumps, a water transfer pump, gas recirculation pumps, phase separators, storage tanks for oxygen (O2) and hydrogen (H2), heat exchangers, isolation valves, pressure regulators, interconnecting tubing, nitrogen purge provisions, and instrumentation for control and monitoring purposes. The regenerative fuel cell (RFC) thus formed is a completely closed system which is capable of autonomous cyclic operation. The test rig provides direct current (DC) load and DC power supply to simulate power consumption and solar power input. In addition, chillers are used as the heat sink to dissipate the waste heat from the electrochemical stack operation. Various vents and nitrogen (N2) sources are included in case inert purging is necessary to safe the RFC test rig.

Alkaline soluble maleimide based tetrapolymers which were prepared by free radical copolymerization are found to be suitable for use as non-imaginable resists in multilevel photolithographic processing. These materials offer widely variable undercut rates because of the ability to vary the composition during free radical polymerization and show little or no scumming when used in lift-off resist. This new polymer system may also be used as the base soluble resin in a photoresist formulation or a base soluble antiflective coating composition as well as used in making lift-off resists.

Thin film imaging processes such as top surface imaging (TSI) are candidates for sub-150 nm lithography using 193 nm lithography. Single component, non-chemically amplified, positive tone TSI photoresists based on phenolic polymers demonstrate good post-etch contrast, resolution, and minimal line edge roughness, in addition to being the most straightforward thin film imaging approach. In this approach, ArF laser exposure results directly in radiation- induced crosslinking of the phenolic polymer, followed by formation of a thin etch mask at the surface of the un- exposed regions by vapor-phase silylation, followed by reactive ion etching of the non-silylated regions. However, single component resists based on poly(para-hydroxystryene) (PHS), such as MicroChem's Nano MX-P7, suffer from slow photospeed as well as low silylation contrast which can cause reproducibility and line-edge-roughness problems. We report that selected aromatic substitution of the poly(para- hydroxystryene) polymer can increase the photospeed by up to a factor of four relative to un-substituted PHS. In this paper we report the synthesis and lithographic evaluations of four experimental TSI photoresists. MX-EX-1, MX-EX-2, MX- EX-3 and MX-EX-4 are non-chemically amplified resists based on aromatic substitutions of chloro- and hydroxymethyl- groups and PHS. We report optimized lithographic processing conditions, line edge roughness, silylation contrast, and compare the results to the parent PHS photoresist.

It is well known that onium salt structure has an influence on resist resolution and post exposure delay stability as well as solubility in typical resist solvents. As a result of our study, it was found that resists have higher contrast when t-butylphenyl substituents replaced phenyl or alkyl substituents in the cation segment of onium-type photoacid generators in both iodonium and sulfonium systems. Dissolution inhibition appeared to play a primary role. In this paper we also report the results of our investigation into onium-type photoacid generators possessing reduced diffusion, lower volatility and suitable acidity to cleave common protecting groups such as t-butoxycarbonyl, acetal and t-butyl. Substituted benzene sulfonic acids were very useful for cleaving common protecting groups in polyhydroxystyrene based Deep-UV resist systems. The addition of alkyl groups to the ring had only slight effect on acid diffusion. Perfluoro sulfonic acids were required to cleave adequately, the acid stable leaving groups in methacrylate resist systems.

Exposures leading to 0.18 micrometer or better resolution are now being demanded by IC development. Photolithography using 193 nm exposure tools is the leading technology for the development of these next generation of devices. We are reporting on our development efforts on the TER resist system, which is a single layer resist designed for image evaluation applications at 193 nm exposure wavelengths. The TER-system has been developed to allow equipment manufacturers to evaluate their equipment, to provide R&D lithographers with materials to qualify their 193 nm equipment and to determine process control parameters. The TER-system is a chemically amplified methacrylate resist terpolymer. It is composed of methyl methacrylate (MMA), methacrylic acid (MAA) and an acid labile acrylic ester. We have evaluated different leaving groups as the acid labile component and we report on the initial results of several. We also examined different onium salts as the PAG component. One such example is di(t- butylphenyl)-iodonium p-toluenesulfonate and we report on other examples which were used. We evaluated the thermal stability of the resins and thermal analysis showed they start to decompose at about 125 degrees Celsius when tetrahydropyranyl methacrylate is used. Other more thermally stable systems were also evaluated. Post apply bake (PAB) temperatures of 100 - 125 degrees Celsius were preferably used with the tetrahydropyranyl ester. Other more thermally stable esters, such as tetrahydro-4-methyl-2-oxo-2H-pyran-4-yl methacrylate (mevalonic lactone), ethoxy-ethyl methacrylate and 3-oxo-cyclohexyl methacrylate, also are described. Exposures in the range of 5 - 50 mJ/cm 2 were typical and varied depending on the ester, the PAG, and other processing parameters. The acid catalyzed reaction rates after exposure were observed to be rapid. In all cases, post exposure bake (PEB) was typically carried out at 10 degrees Celsius or lower. Initial exposure evaluations at 193 nm and 248 nm show good resolution and image fidelity. The TER-system produced better than 0.225 micrometer resolution using 248 nm exposure equipment (NA equals 0.55) suggesting that better than 0.18 micrometer resolution is possible with 193 nm exposures. Results of resist synthesis, formulation and evaluation are presented.

Abstract Southwest Research Institute performed a test program on electrical and hydraulic connectors for use in deep water environments. Four electrical and six hydraulic connectors were tested under the direction of DeepStar 300 committee. Make/break forces, allowable misalignment, sealing, and power carrying capabilities were evaluated under conditions simulating 6000 feet of sea water. This paper describes the test fixture and procedure developed for the program and presents the test results in general to show the state of readiness of electrical and hydraulic connectors for deep water service. Introduction The DeepStar program is a cooperative industry project developedby Texaco to examine deep water subsea production systems for installation in the Gulf of Mexico. This testing project was awarded to Southwest Research Institute (SWRI) by the DeepStar 300 committee. Four electrical and six hydraulic connected were tested. The participating vendors were: Electrical Connector VendorsLockheed - Martin, Challenger MarineHawke Cable Glands LimitedTronic Electronic Services LimitedOcean Design Incorporated Hydraulic Coupler VendorsNational Coupling Company, IncorporatedCooper Oil Tool Division of Cooper IndustriesSnapTite IncorporatedCad Kurt Walther GMBH & Company, KGStaubli, Hydraulic and Pneumatic DivisionKvaemer FSSL Incorporated The 300 committee would like to thank each of the connector vendors for donating their time and materials to this program. Without their contributions the program could not have been accomplished. The test program was intended to demonstrate the capability of currently available electrical connectors and hydraulic couplers to operate at the DeepStar Operating Conditions. this required developing a test fixture and appropriate test procedures. The 300 committee anticipates that participating DeepStar oil companies will use the information gained in this program for future control system designs. A further intent of the program was to make a test fixture and procedures available to industry beyond DeepStar. The test fixture and procedures developed in this program are available for use in the future for qualification tests for a specific deep water installation or to assist manufacturers in developing new products and improving existing ones. Program Findings and Recommendations This section relays the findings and recommendations generated in the CTR A305/306 test program. At the most basic level, it must be understood that this program was not a qualification program. Therefore it should not be concluded that some connectors 'passed' DeepStar while others 'failed.' The connectors were of different designs for different applications. Each was tested to criteria established by the individual manufacturer rather than against a uniform standard. Secondly, it must be understood that the DeepStar test procedures reflect the need of an equipment manufacturer to design his equipment to be a suitable host to the electrical or hydraulic connectors that are necessary for the functioning of an overall system.

Results are presented from a study undertaken to evaluate resist casting solvent composition and molecular weight variation in PMMA for electron beam exposure. PMMA cast in several solvent systems have been evaluated for lithographic performance. Additionally, formulations in chlorobenzene with minor variations in molecular weight have been evaluated for batch-to- batch uniformity. A 10 KeV MEBES electron beam system has been used to study resist sensitivity, contrast, and process latitude. Using a two-factor, three level factorial designed experiment, prebake and development time have been varied as controlled process factors. Samples with varying molecular weights were shown to have wide process latitude. These samples gave comparable performance while their molecular weights varied from 539 K to 614 K, and polydispersity varied from 3.3 to 6.1. Resist samples with chlorobenzene, PGMEA (propylene glycol monomethyl ether acetate), and anisole as the casting solvent resulted in equivalent performance.

This paper describes the use of a 193 nm surface imaging resist in a new small-field, deep-UV projection exposure system. The 193 nm surface imaging technology utilizes commercial photoresists, in conjunction with a small field step-and-repeat exposure system. Typical processing characteristics of the imaging chemistry are presented, along with a detailed description of the projection exposure system. The resist uses vapor phase silylation with oxygen RIE developing and has been shown to provide wide focus latitude and better than 0.2 micrometers resolution. The imaging system uses a catadioptric lens with 0.5 NA for 0.20 images.

It is no longer possible to have just the best technology in the semiconductor equipment and materials market and remain successful. Each product tends to last for only one generation of IC devices. This high rate of imaging technology change means that the material or equipment manufacturer must have a large base of expertise to keep up with the rapidly changing needs and requirements of the technology. Also necessary is a large source of capital to finance development, manufacturing, and testing equipment. Unfortunately, the sequence of short business cycles, with limited lifetimes for each lithographic technology, is expected to continue for at least another ten years, until some technology or technologies, with long lifetimes through a large number of device generations, is firmly in place. The intent of this paper is to compare the potential IC manufacturing requirements, product timing, and the technological capabilities of i-line, DUV (248 nm), VUV (193 nm), and x-ray. From this we intend to project the technological potential of each. To do this we intend to determine the limiting resolution and DOF of each technology, evaluate the resist and processing capabilities, examine the engineering requirements. We will evaluate the impact of phase shift mask technology, surface imaging, and planarization and their impact on lithographic potential. From this information we will provide a comparison of these four technologies. This data will then be compared to IC device requirements and timetables from which a lithographic product need and lifetime relationship can be determined for each technology.

A variety of novolac-based polymers and blends with photoactive compounds were studied for their suitability as resists in a 193-nm positive-tone silylation process. The addition of photoactive compound was found to reduce the sensitivity of the resist and to hinder the diffusion of the silylating agent. Pure meta-cresol novolacs and polyvinylphenols, both of which can be polymerized to high (> 10,000) molecular weights show the best sensitivity for this process. Diffusion rates correlate with the molar volume of the silylating agent, although the activation energy does not. Resolution of 0.2-micrometers line-and-space gratings has been achieved with the polyvinylphenol and meta-cresol novolac resins.

The accelerated drive toward 0.5 and 0.3 urn optical imaging is putting severe pressure on both the equipment and photoresist vendors. Materials must give both high resolution and high process latitude. These needs led to the develop- ment of EL2015 positive photoresist series. This is a high contrast, high resolution photoresist series based on the same chemical concepts used in our PR1O24MB resists. This new resist contains a 2,1,5-naphthoquirionediazidesulfonate ester of a special novolac as its photoactive component. This is combined with an improved novolac resin for better film integrity. EL2015 is a versatile positive resist optimized for g-, h-, i-line, and broadband exposure tools. Resolution of better than 0.50 urn has been routinely obtained with current 0.40 NA i-line steppers and 0.40 urn resolution at best focus. A focus latitude of greater than 1.5 urn for 0.5 urn images with an exposure latitude of 30-50% has been demonstrated on i-line equipment. Finally, the thermal stability and plasma etch resistance of EL2015 has been found to be comparable to current high resolution g-line photoresists.

This paper studies e effects of process conditions and dye additives on sidewall profiles using RS—1 designed experiments. We have explored the mechanism of forming negative sidewall profiles (above 90) in a positive photoresist, the dependence of depth of focus (DOF) and exposure latitude upon sidewall angle The resist studied is a positive, dual purpose (g—, i—line) resist, ULTRAMAC EL2015. The study presented in this paper was done in i—line but similar phenomena were observed in g—line as well. The effect of two different actirtic dyes in various concentrations on wall angle control is demonstrated. The two dyes investigated are both soluble in resist solvent but their solubility in developer is very different and their effect on required exposure energy is different. The contribution of the dyes to the absorption of the resist, their effect on swing curve and surface inhibition is evaluated and compared. The surface inhibition effect of undyed resist has been determined to be the most critical parameter influencing profiles, as increased post exposure bake temperature increases sidewall profile angle.

193 nm radiation causes direct photocrosslinking of polymer films which is sufficient to generate silylation selectivity under appropriate conditions. A variety of phenolic based polymers and blends with photoactive compounds were studied for their suitability as resists in a 193 nm, positive-tone, silylation process. Meta-cresol novolac resists and polyvinylphenol resists show the best sensitivity for this process. The threshold dose required to restrict diffusion of the silylating agent depends strongly on the composition of the resist. Sensitivities range from 12 mJ/cm2 to over 100 mJ/cm2 for various novolac and polyvinylphenol materials. Wide variations in sensitivity have been found between different synthetic methods for the same resin, different molecular weight characteristics, and different functional modifications.

A single injection of prolactin into seawater-acclimated flounder, Platichthys stellatus , caused a decrease in the permeability of the bladder to water (mucosa to serosa) with an increase in sodium absorption by the bladder and a decrease in urine osmolality and sodium concentration. A simultaneous increase occurred in plasma sodium and osmolality. Maximal effects were observed 2 days after the injection, and the effects disappeared after 4 days. Transfer of seawater fish to fresh water similarly resulted in a maximal decrease in bladder water permeability and in serum sodium concentration by 2 days after transfer. Serum sodium increased to the normal freshwater level by 14 days. Bladder water permeability increased significantly 2 days after transfer from fresh water to sea water, and attained the fully adapted level by 14 days, whereas plasma sodium increased maximally by 2 days after transfer and decreased to the normal level by 7 days. A change in pituitary prolactin content as determined by the xanthophore pigment-dispersion test was observed within 12 hr after salinity transfer. The parallelism between the time of response of serum and urine adjustments and urinary bladder permeability following prolactin treatment and that following changes in environmental salinity adds additional support for an osmoregulatory function for the urinary bladder in the starry flounder.

The second year of a renewed net fishery in western Kentucky reservoirs was monitored by catch report analysis of data obtained by onboard observers describing gear effectiveness, species caught, and length group structure of the catch. Twenty-nine permit fishermen removed a total of 651 metric tons of commercial species valued at more than $370,000. Total landings increased 65% over the first year. Reported paddlefish (Polyodon spathula) landings decreased 58% - from 15 to 4% of the catch by weight and from 26 to 2% of the value. Buffalofishes (Ictiobus spp.) and catfishes (Ictaluridae) comprised 56 and 21% of the catch by weight, respectively. Trammel nets (89-114 mm) were found to be most effective for harvesting buffalofishes while gill nets were used selectively for catfishes. Catch per effort of experienced fishermen was 49% higher than for inexperienced fishermen. Daily catch reports provided a reliable estimate of total harvest when monitored and filed.

1. 1. DDT inhibited activity of Na-K-ATPase and Mg-ATPase in gills of rainbow trout ( Salmo gairdneri ) adapted to fresh water (FW), 1 3 sea water ( 1 3 SW) and SW. 2. 2. A negative correlation was found between gill Na-K-ATPase (decrease) and serum sodium (increase) in treated fish in SW. 3. 3. Enzyme activity was inhibited in FW fish, but no osmoregulatory impairment was found. This may indicate a minor or nonexistent role for gill Na-KATPase in FW osmoregulation. 4. 4. Enzyme activity was inhibited in trout acclimated to SW (SW > 1 3 SW > FW).

Correlation of coronary arteriosclerosis with sexual maturation was found in rainbow and steelhead trout. All sexually mature nonanadromous rainbow, precocial male steelhead, and adult spawning steelhead had myointimal hyperplasia but it was infrequent in immature juveniles. Lesion severity in adult rainbow and precocial steel head approach that of spawning steelhad.

Commercial fishermen reported removing 1,006 sport fishes from their nets during the 5-month 1980-1981 season. Observations of field monitors who accompanied these fishermen during retrieval operations revealed that the commercial gill nets and trammel nets (89-114 mm bar mesh) used for harvesting buffalofish (Ictiobus spp.) and common carp (Cyprinus carpio) in two mainstream Kentucky reservoirs had minimal impact on sport fish. The sport-fish catch was less than 1/1,000 m of net, with 65% of those in good condition when released. No largemouth bass (Micropterus salmoides) mortality was observed in the 39 km of gear monitored.

An experiment was conducted to evaluate approximate analytical methods for predicting the reduction in parachute drag due to forebody wake effects. The drag of a 20/sup 0/ conical ribbon parachute was measured at several axial stations behind an ogive-cylinder forebody with and without fins. The same parachute was tested in undisturbed flow (where wake effects were negligible) so that the effects of suspension line length on parachute drag could be separated from the drag losses caused by the turbulent wake. Total head pressure surveys were made across the forebody wake and integrated across the canopy skirt area to determine the effective dynamic pressure acting on the parachute. Experimental results confirmed the validity of the underlying physical model of the parachute/wake interaction: the ratio of parachute drag behind a forebody divided by wake-free parachute drag is equal to the ratio of effective dynamic pressure acting on the parachute divided by freestream dynamic pressure.

Kevlar-29, an aramid fiber manufactured by DuPont, is being used on parachute systems requiring high strength-to-weight ratios or resistance to sustained high temperatures. Tests of parachutes using Kevlar webbing, braided cords, ribbons, and thread have demonstrated that these Kevlar materials can be used successfully in ribbon parachutes with no detrimental effects on performance. A few changes must be made in the design of a ribbon parachute to accommodate Kevlar's high modulus. Examples of parachutes that use Kevlar suspension lines, radials, ribbons, reefing lines, bridles, and skirt bands are presented to show that they are much lighter and more resistant to aerodynamic heating than their all-nylon counterparts.

1. 1. A reduction in osmotic permeability to water and an increase in sodium and chloride absorption were observed in the isolated urinary bladder of three species of flounders after their acclimation to hypotonic media and after prolactin treatment. 2. 2. Bladders of stenohaline fresh-water fishes were nearly impermeable to water; active absorption of sodium was indicated in some species. 3. 3. Osmotic permeability was variable in marine fishes, but was especially noticeable in aglomerular Porichthys and Lophius. 4. 4. Euryhaline fishes of sea-water origin modify their bladders from a permeable state in sea water to a relatively impermeable state in fresh water. Prolactin seems to be involved in this modification. Bladders from euryhaline fish of fresh-water origin appear impermeable, irrespective of environmental salinity.

Results are presented for twenty-nine flight tests of a 22.2-ft (6.8-m) diameter ribbon parachute (reefed for 0.5 sec) with a nominal 2000-lb (907-kg) store. The design, fabrication, and packing of the parachute system are discussed. Low altitude drop tests were made with F-4 and A-4 aircraft at Mach numbers from 0.57 to 1.22, and rocket-boosted tests were made at Mach numbers from 1.62 to 1.70, the latter corresponding to a maximum dynamic pressure of 2720 psf (130 kN/m2). The maximum measured snatch load, reefed stage opening shock, and second stage opening shock were approximately 65 klb (289 kN), 165 klb (734 kN) and 150 klb (667 kN), respectively. The measured load data and sequence of parachute function times are relatively consistent and repeatable. There is no discernible effect of Mach number on the steady-state drag area of the reefed parachute at Mach numbers from 0.7 to 1.50. Nomenclature At,'Ae = effective canopy inlet and exit areas, respectively, during inflation process

This study shows that many of the duties usually done only by the dentist can be performed accurately and efficiently by trained chairside assistants. In the experimental phase, about two fifths of the dentist’s work was delegated to auxiliaries. The findings of this phase are compared with those of the base-line and training phases.

A utility model based upon three possible referents for defining educational needs is presented. This model postulates that an individual's “value” to his society may be determined by his position on a consumption-production continuum. It is suggested that these dimensions and criteria might be useful to educational planners and designers.

Either minced or homogenized preparations of head kidney tissue from Tilapia mossambica were incubated with different radioactive precursors. From acetate–l–14C only a small yield of progesterone was obtained. Cholesterol–4–14C was actively metabolized into four major unidentified compounds, observed also after incubation with Tilapia spleen, but its contribution to corticosteroidogeneis could not be demonstrated. Conversely, rat adrenal tissue promptly converted cholesterol–4–14C into progesterone, corticosterone, and 11–dehydrocorticosterone. With minced head kidney, progesterone–4–14C gave rise to 17α–hydroxyprogesterone, 11–deoxycortisol, cortisol, cortisone, 11–deoxycorticosterone, corticosterone, 11– dehydrocorticosterone, 11β–hydroxyprogesterone, and 21–deoxycortisol. Homogenization caused a greater accumulation of those metabolites proximal to progesterone and a reduction in the total steroid profile. Aldosterone formation did not occur from progesterone–4–14C or from corticosterone–4– 14C. The la...

This paper reviews selected literature on pesticide interactions in aquatic habitats, with special reference to their effects on fishes, and is hopefully an objective critique of research to date, and a projection of future needs in this field. The questions that have been asked are compared to the answers that must be provided. Factors (physical and biological) that affect toxicity are presented to define the data required for the judgment of a “safe” environmental concentration as related to LC50 (mean lethal concentration). Residue analyses give some indications of the action and effects of pesticides on fishes and their ecosystems. Analytical techniques are briefly reviewed. Research programs necessary for the detection of any sublethal damage to a population are suggested in the hope that in the near future direct mortality may not be the chief criteria of danger from pesticides.

Three varieties of osmoregulatory surface in teleosts are considered herein: the intestine, which is under bihormonal control (cortisol and prolactin); the urinary bladder, which is under unihormonal control (prolactin); and the gallbladder, which is not under hormonal control. Water movement in the isolated intestine of the eel increases during seawater adaptation, and cortisol is required to maintain the enhanced water absorption. This water movement is associated with the active transfer of ions, especially Cl ions. In freshwater eels, potential difference (PD) and short-circuit current (Isc) across the intestine were nearly zero or slightly serosa-negative, whereas in seawater eels and in freshwater eels injected with cortisol, the negativity of the PD and Isc increased. Development of a Cl− pump in seawater and cortisol-treated freshwater eels was further confirmed by ion-flux study. Prolactin injection into seawater eels decreased the rate of salt and water absorption in the gut. Prolactin seems to act on the gut surface as an antagonist to cortisol, by suppressing the Cl− pump and lowering permeability to water. In the isolated urinary bladder of flounders, water movement is reduced after transfer to fresh water or to dilute sea water. Prolactin injection into seawater flounders decreased osmotic permeability to water to the level of freshwater fish. This water movement is also associated with active transport of ions: ouabain inhibited both net influx of Na ions and water. In contrast to the eel intestine, there is no difference in net Na+ fluxes between freshwater and seawater flounder bladders; prolactin stimulates Na+ reabsorption. In sea water, the flounder bladder seems to absorb water from the urine by actively absorbing Na ions. In fresh water, the bladder seems to absorb mainly Na (and Cl) ions, and prolactin is involved in these changes by decreasing permeability to water and by stimulating the Na+ pump. On the other hand, the ion- and water-absorption capacity of the gallbladder isolated from the eel does not show any response to environmental salinity change nor to cortisol or prolactin treatment. It is suggested that cortisol may act primarily at the level of ion pumps, and prolactin primarily at the level of permeability barriers.