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The National Ignition Facility (NIF) at Lawrence Livermore National Laboratory has been operational since March 2009 and has been transitioning to a user facility supporting ignition science, high ...

Dislocation remains a major concern after total hip replacement, and is often attributed to malposition of the components. The optimum position for placement of the components remains uncertain. We have attempted to identify a relatively safe zone in which movement of the hip will occur without impingement, even if one component is positioned incorrectly. A three-dimensional computer model was designed to simulate impingement and used to examine 125 combinations of positioning of the components in order to allow maximum movement without impingement. Increase in acetabular and/or femoral anteversion allowed greater internal rotation before impingement occurred, but decreases the amount of external rotation. A decrease in abduction of the acetabular components increased internal rotation while decreasing external rotation. Although some correction for malposition was allowable on the opposite side of the joint, extreme degrees could not be corrected because of bony impingement. We introduce the concept of combined component position, in which anteversion and abduction of the acetabular component, along with femoral anteversion, are all defined as critical elements for stability.

The National Ignition Facility (NIF) is a 192-beam laser facility presently under construction at LLNL. When completed. NIF will be a 1.8-MJ, 500-TW ultraviolet laser system. Its missions are to obtain fusion ignition and to perform high energy density experiments in support of the U.S. nuclear weapons stockpile. Four of the NIF beams have been commissioned to demonstrate laser performance and to commission the target area including target and beam alignment and laser timing. During this time, NIF demonstrated on a single-beam basis that it will meet its performance goals and demonstrated its precision and flexibility for pulse shaping, pointing, timing and beam conditioning. It also performed four important experiments for Inertial Confinement Fusion and High Energy Density Science. Presently, the project is installing production hardware to complete the project in 2009 with the goal to begin ignition experiments in 2010. An integrated plan has been developed including the NIF operations, user equipment such as diagnostics and cryogenic target capability, and experiments and calculations to meet this goal. This talk will provide NIF status, the plan to complete NIF, and the path to ignition.

The National Ignition Facility (NIF) at Lawrence Livermore National Laboratory (LLNL) has been operational since March 2009 and has been transitioning to a user facility supporting ignition science, high energy density science (HEDS), national security applications, and fundamental science. The facility has achieved its design goal of 1.8 MJ and 500 TW of 3ω light on target, and has performed target experiments with 1.9 MJ at peak powers of 410 TW. The facility is on track to perform over 200 target shots this year in support of all of its user communities. The facility has nearly 60 diagnostic systems operational and has shown flexibility in laser pulse shape and performance to meet the requirements of its multiple users. Progress continues on its goal of demonstrating thermonuclear burn in the laboratory. It has performed over 40 indirect-drive experiments with cryogenic-layered capsules. New platforms are being developed for HEDS and fundamental science. Equation-of-state and material strength experiments have been done on a number of materials with pressures of over 50 MBars obtained in diamond, conditions never previously encountered in the laboratory and similar to those found in planetary interiors. Experiments are also in progress investigating radiation transport, hydrodynamic instabilities, and direct drive implosions. NIF continues to develop as an experimental facility. Advanced Radiographic Capability (ARC) is now being installed on NIF for producing high-energy radiographs of the imploded cores of ignition targets and for short pulse laser-plasma interaction experiments. One NIF beam is planned for conversion to two picosecond beams in 2014. Other new diagnostics such as x-ray Thomson scattering, low energy neutron spectrometer, and multi-layer reflecting x-ray optics are also planned. Incremental improvements in laser performance such as improved optics damage performance, beam balance, and back reflection control are being pursued.

The National Ignition Facility has been used to compress deuterium-tritium to an average areal density of ~1.0±0.1 g cm(-2), which is 67% of the ignition requirement. These conditions were obtained using 192 laser beams with total energy of 1-1.6 MJ and peak power up to 420 TW to create a hohlraum drive with a shaped power profile, peaking at a soft x-ray radiation temperature of 275-300 eV. This pulse delivered a series of shocks that compressed a capsule containing cryogenic deuterium-tritium to a radius of 25-35 μm. Neutron images of the implosion were used to estimate a fuel density of 500-800 g cm(-3).

We demonstrate the hohlraum radiation temperature and symmetry required for ignition-scale inertial confinement fusion capsule implosions. Cryogenic gas-filled hohlraums with 2.2 mm-diameter capsules are heated with unprecedented laser energies of 1.2 MJ delivered by 192 ultraviolet laser beams on the National Ignition Facility. Laser backscatter measurements show that these hohlraums absorb 87% to 91% of the incident laser power resulting in peak radiation temperatures of T(RAD)=300 eV and a symmetric implosion to a 100 μm diameter hot core.

The National Ignition Facility (NIF) at Lawrence Livermore National Laboratory has been designed to support a wide variety of high energy density science (HEDS) experiments, including the demonstration of inertial fusion ignition and burn. To meet this goal, its 192-beam frequency-converted neodymium-glass laser must deliver up to 1.8-MJ total energy at 351 nm, with peak power of 500 TW and precisely-controlled temporal pulse shapes spanning two orders of magnitude. Over the past two years, a series of detailed measurements have been performed on one beamline of the NIF laser at 1omega(1053 nm), 2omega(526.5 nm), and 3omega(351 nm). Results of these experiments lend confidence to the expectation that NIF will meet its laser performance design criteria and that it will be able to simultaneously deliver the temporal pulse shaping, focal spot conditioning, peak power, shot-to-shot reproducibility, and power balance required for indirect-drive fusion ignition campaigns. The NIF final optics system has also been demonstrated to be capable of operating at 2omega energies of up to 17.9 kJ/beamline-3.4 MJ for a similarly configured 192-beam NIF. We discuss the status of NIF commissioning, and the nature and results of these measurement campaigns.

The National Ignition Facility (NIF) is the world's largest laser system. It contains a 192 beam neodymium glass laser that is designed to deliver 1.8 MJ at 500 TW at 351 nm in order to achieve energy gain (ignition) in a deuterium-tritium nuclear fusion target. To meet this goal, laser design criteria include the ability to generate pulses of up to 1.8 MJ total energy, with peak power of 500 TW and temporal pulse shapes spanning 2 orders of magnitude at the third harmonic (351 nm or 3omega) of the laser wavelength. The focal-spot fluence distribution of these pulses is carefully controlled, through a combination of special optics in the 1omega (1053 nm) portion of the laser (continuous phase plates), smoothing by spectral dispersion, and the overlapping of multiple beams with orthogonal polarization (polarization smoothing). We report performance qualification tests of the first eight beams of the NIF laser. Measurements are reported at both 1omega and 3omega, both with and without focal-spot conditioning. When scaled to full 192 beam operation, these results demonstrate, to the best of our knowledge for the first time, that the NIF will meet its laser performance design criteria, and that the NIF can simultaneously meet the temporal pulse shaping, focal-spot conditioning, and peak power requirements for two candidate indirect drive ignition designs.

The National Ignition Facility (NIF) is a 192 beam Nd-glass laser facility presently under construction at LLNL. When completed, NIF will produce 1.8 MJ, 500 TW of ultraviolet light making it the world's largest and most powerful laser system. NIF will be the world's preeminent facility for performing experiments for Inertial Confinement Fusion (ICF) and High Energy Density Science (HEDS). The Project, begun in 1995, is over 80% complete. The building and the beam path are essentially complete. Nearly all of the functionality of the laser subsystems has been demonstrated. NIF has demonstrated on a single beam basis that it meets its performance goals and shown the laser's precision and flexibility for pulse shaping, pointing, and timing. Beam conditioning techniques, important for target performance, were also demonstrated. The focal spot can be tailored to user specifications using phase plates. Temporal smoothing using smoothing by spectral dispersion (SSD) as well as polarization smoothing was demonstrated. The remaining work is mostly to complete the optics and install them in the beam path and complete the utilities. Presently, eight beams have been activated through the amplifiers and spatial filters to the switchyard wall. Over 150 kJ of 1ω light has been produced with just 4% of the NIF capacity activated. The Project is scheduled for completion in 2009 and plans have been developed to begin ignition experiments in 2010. This talk will provide NIF status, the plan to complete NIF, and the path to ignition.

The National Ignition Facility (NIF) is a 192-beam laser facility presently under construction at LLNL. When completed, NIF will be a 1.8-MJ, 500-TW ultraviolet laser system. Its missions are to obtain fusion ignition and to perform high energy density experiments in support of the U.S. nuclear weapons stockpile. Four of the NIF beams have been commissioned to demonstrate laser performance including target and beam alignment. During this time, NIF demonstrated on a single-beam basis that it will meet its performance goals and demonstrated its precision and flexibility for pulse shaping, pointing, timing and beam conditioning. It also performed four important experiments for inertial confinement fusion and high energy density science. Presently, the project is installing production hardware to complete the project in 2009 with the goal to begin ignition experiments in 2010. An integrated plan has been developed including the NIF operations, user equipment such as diagnostics and cryogenic target capability, and experiments and calculations to meet this goal

To better understand the evolutionary history of Linanthus (Polemoniaceae) and its relatives, molecular phylogenies based on DNA sequence data from the internal transcribed spacer (ITS) region of nrDNA and the chloroplast gene matK were estimated using several methods. Our data suggest two separate and well-supported lineages of Linanthus in close association with two other genera-Leptodactylon and Phlox. These results agree with previous molecular systematic work on the Polemoniaceae, but do not support the traditional classification of the genus as a natural group, nor do they support the sectional classification within the genus. With a distribution centered primarily in western North America and a high degree of endemism in the California Floristic Province, it has been suggested by Raven and Axelrod that the origin and diversification of Linanthus and its relatives were tied to the development of a summer-dry climate in western North America, which began around 13-15 million years ago (mya). Increased drying during the Pliocene (1.2-5 mya) has also been hypothesized by Axelrod to have led to an increase in plant speciation in California and adjacent areas. Divergence times within the Linanthus lineages were estimated from the ITS and matK gene trees. A log-likelihood ratio test could not reject clock-like evolution for the matK data; however, the clock was strongly rejected for the ITS data set. Although ITS molecular evolution was not clock-like, the estimated times of divergence were similar to those of the matK data set. Within both lineages of Linanthus there seems to have been considerable diversification that has occurred since the Pliocene.

First results from the analysis of neutron image data collected on implosions of cryogenically layered deuterium-tritium capsules during the 2011-2012 National Ignition Campaign are reported. The data span a variety of experimental designs aimed at increasing the stagnation pressure of the central hotspot and areal density of the surrounding fuel assembly. Images of neutrons produced by deuterium–tritium fusion reactions in the hotspot are presented, as well as images of neutrons that scatter in the surrounding dense fuel assembly. The image data are compared with 1D and 2D model predictions, and consistency checked using other diagnostic data. The results indicate that the size of the fusing hotspot is consistent with the model predictions, as well as other imaging data, while the overall size of the fuel assembly, inferred from the scattered neutron images, is systematically smaller than models' prediction. Preliminary studies indicate these differences are consistent with a significant fraction (20%–25%) of the initial deuterium-tritium fuel mass outside the compact fuel assembly, due either to low mode mass asymmetry or high mode 3D mix effects at the ablator-ice interface.

The National Ignition Facility at Lawrence Livermore National Laboratory was formally dedicated in May 2009. The hohlraum energetics campaign with all 192 beams began shortly thereafter and ran until early December 2009. These experiments explored hohlraum-operating regimes in preparation for experiments with layered cryogenic targets. The hohlraum energetic series culminated with an experiment that irradiated an ignition scale hohlraum with 1 MJ. The results demonstrated the ability to produce a 285 eV radiation environment in an ignition scale hohlraum while meeting ignition requirements for symmetry, backscatter and hot electron production. Complementary scaling experiments indicate that with ∼1.3 MJ, the capsule drive temperature will reach 300 eV, the point design temperature for the first ignition campaign. Preparation for cryo-layered implosions included installation of a variety of nuclear diagnostics, cryogenic layering target positioner, advanced optics and facility modifications needed for tritium operations and for routine operation at laser energy greater than 1.3 MJ. The first cyro-layered experiment was carried out on 29 September 2010. The main purpose of this shot was to demonstrate the ability to integrate all of the laser, target and diagnostic capability needed for a successful cryo-layered experiment. This paper discusses the ignition point design as well as findings and conclusions from the hohlraum energetics campaign carried out in 2009. It also provides a brief summary of the initial cryo-layered implosion.

A single beamline of the National Ignition Facility (NIF) has been operated at a wavelength of 526.5 nm (2 omega) by frequency converting the fundamental 1053 nm (1 omega) wavelength with an 18.2 mm thick type-I potassium dihydrogen phosphate (KDP) second-harmonic generator (SHG) crystal. Second-harmonic energies of up to 17.9 kJ were measured at the final optics focal plane with a conversion efficiency of 82%. For a similarly configured 192-beam NIF, this scales to a total 2 omega energy of 3.4 MJ full NIF equivalent (FNE).

The dispersion relation of magnetostatic surface waves propagating in a ferromagnetic film of finite dimensions is derived. Specifically, a consideration of the finite width of the sample is introduced to the previous treatments of magnetostatic surface‐wave propagation. The inclusion of a finite width produces a multiplicity of propagating modes, which can be excited individually or collectively, depending on experimental conditions. In addition, the finite width allows the excitation of magnetostatic volume waves, which exist over a narrow frequency range just below the range of magnetostatic surface waves. All aspects of the theoretical analysis are supported by measurements made on magnetostatic surface‐wave propagation at frequencies around 1 and 9 GHz in yttrium iron garnet samples of different widths.

During periods of network stress, network management (real-time monitoring and control of the network) assures optimum call-carrying capacity. To assure timely reactions to network overloads and failures, the national Network Operations Center coordinates the activities of a set of network management operations centers. Supporting the Network Operations Center, the Network Operations Center System collects data for major network elements and, within minutes, provides a national overview of exceptional conditions.

With measured values of arterial blood gas tensions, of expired respiratory gas fractions, and volume of the expired ventilation, the determinants of alveolar oxygen tension (PAO2) were used to evaluate their influence on the development of the arterial hypoxemia that occurs in spontaneously breathing patients undergoing hemodialysis using an acetate dialysate. Dialysis produced no significant changes in the alveolar-arterial O2 tension gradient (AaDO2). The extracorporeal dialyzer removed an average of 30 ml.m-2.min-1 of CO2. Accordingly the pulmonary gas exchange ratio (R) dropped from a mean predialysis value of 0.81 to 0.62 (P less than 0.001). The arterial CO2 tension remained constant throughout, whereas the minute ventilation, both total (P less than 0.01) and alveolar (P less than 0.01), decreased during dialysis. This decrease in ventilation accounts for more than 80% of the fall in PAO2. During dialysis there was a decrease (P less than 0.001) in arterial oxygen tension (PaO2), which varied among the individuals from 9 to 23% of control. During the postdialysis hour PaO2 returns to control values concomitant with increase in ventilation. The quantitative gas exchange relationships among R, alveolar ventilation, and AaDO2 predict the PaO2 values actually measured.

Evaluation of disturbances in lung function requires a variety of physiological measurements. Absolute values for such determinations are meaningless because the significance of the measured quantities varies with the age, sex, and body size of the subject. At present the norm which is compared with the measured value must be derived from tables or in some instances must be individually calculated. A computer program has been developed which evaluates the measured values of lung function by comparing them with accepted norms. The computer program is written in the BASIC programming language and minimal involvement by laboratory personnel is required. Stored in the computer program are matrices containing the regression coefficients used for the computation of the predicted values for each of the pulmonary function tests based upon the patient's sex, height, age, and weight. When the measured value falls outside of the 95 percent confidence limits, the measured value is flagged on a computer printout, immediately denoting those values which are abnormal. In approximately 5 minutes after the input of data, the printout evaluation is available for addition to the patient's record.

Summary Dynamic compliance of the lung-thorax system was measured during artificial ventilation in anesthetized paralyzed patients undergoing correction of acquired valvular heart disease. Heart-lung bypass was carried out through a median sternotomy with the pleural spaces bilaterally remaining intact throughout the procedure. During total heart-lung bypass, which averaged 2½ hours, the lungs were statically inflated with 100 per cent oxygen at 10 cm. water pressure. The value of arterial oxygen tension during 99 per cent oxygen breathing was used to assess the magnitude of atelectasis. No significant differences in compliance or atelectasis were found before and after bypass.

Carbon dioxide washout curves were determined in hyperventilated dogs. Direct measurement of mixed venous carbon dioxide tension allowed calculation of changes in whole-body CO2 stores. The average whole-body CO2 dissociation constant in ten studies was 3.73 ml/kg mm. The limiting factor in reaching a new steady-state value was represented by a slow compartment in the washout curve. The average rate constant for this compartment was 0.062 min–1. The slowest compartment in this analysis has a 98% change in 1 hr, therefore the experimentally determined whole-body dissociation constant should closely approximate actual changes in tissue CO2 stores, excluding bone and fat.

An abrupt hysteretic change in bubble size as a function of bias field has been observed in garnet films grown by chemical vapor deposition (CVD). Similar bistable bubbles and their associated transformations have now been observed in double‐layer films grown by liquid‐phase epitaxy (LPE). A slight compositional variation from layer to layer was introduced. Single‐layer LPE films similar to CVD films reported earlier did not display these bistable bubbles. Compositional variations are postulated as the cause of the bistable bubbles, rather than strain variation as previously suggested.

Measurements of the I‐V characteristics of LPE YIG films have been made over several decades of current and voltage. Both Si‐doped and undoped YIG were investigated. All films exhibited regions of non‐Ohmic conduction, where I varied as Vα. Values of α ranging from 1.1 to 2.4 were observed. Evidence of carrier trapping was also found. The measurements are interpreted in light of the conduction mechanism through a two layer structure where the upper layer has a much higher resistivity than the bulk of the film. The model is shown to yield qualitative agreement with the experiments, and direct evidence supporting the model structure is presented.

The design and operation of a novel type of magnetostatic wave transducer is described. The transducer is formed from an interdigital arrangement of narrow, open circuited microstrip fingers, each half an electromagnetic wavelength long. Experimental results in the frequency range 9–9.4 GHz are presented for 2, 4 and 10 finger transducers which are in good agreement with the sin(Nx/2)/sin(x/2) response predicted by simple theory.

Coupling of propagating magnetostatic waves with resonant exchange dominated spin wave modes produces attenuation notches in the magnetostatic wave transmission response. The exchange resonances occur when kex=nπ/d, where kex is the exchange wave number normal to the film plane, n is the mode number and d is the thickness of the epitaxial YIG film. Measurements of attenuation notch depth and position have been performed on as grown LPE‐YIG films and on films whose surface spins were pinned by ion milling, SiO2 deposition or annealing. Coupling was strongest for magnetostatic volume waves with the magnetic bias field normal to the film. Coupling to magnetostatic surface waves was less strong and in accordance with theory magnetostatic volume waves propagating parallel to the magnetic bias field showed zero coupling. The various treatments increased the depth of the attenuation notches and produced a mode pattern consistent with spin pinning asymmetric between the two film surfaces. The probable source of c...

Modern closed-circuit anesthesia employs the technique of introducing a variable mass of anesthetic agent into the rebreathing circuit sufficient to maintain a constant anesthetizing tension at the central nervous system active sites. This method has both a theoretical and a physical foundation. An understanding of anesthesia uptake, the distinction between volume saturation and anesthethetic tension equilibration, and a means of precision administration of volatile vapors are required.

When hard bubbles are translated at sufficiently high velocities, the Bloch lines in the bubbles’ walls are annihilated, resulting in soft bubbles. Investigations of this annihilation phenomenon as a function of Bloch line density were performed in YEuIG and YGdTmIG films. It was found that the velocity required to cause annihilation is inversely proportional to the Bloch line density, while the drive field required to translate the bubbles at this velocity is directly proportional to the Bloch line density. The angle ϑc between the critical velocity and the field gradient is independent of Bloch line density, and virtually invariant from sample to sample, with a value of ϑc?80°. Evidence has been found which indicates the annihilation process involves sequential destruction of Bloch lines.

A model is proposed for the propagation of magnetostatic surface waves in a layered structure consisting of a ground plane and a YIG film separated by a dielectric. The standard assumption of an infinite sample width is replaced with an assumption of a sinusoidal transverse distribution of rf fields. Instead of a single solution, a multiplicity of solutions is found, each with a distinct dispersion relation. Experimental observation of the first two finite‐width modes is in excellent agreement with predicted results derived from the model.

Despite experimental evidence that myocardial depression resulting from rapid transfusion of ACD blood (citrate binds ionic calcium) is avoidable by simultaneous calcium administration, most hypovolemic patients receive calcium either after transfusion or not at all. Similar iatrogenic hypocalcemic myocardial depression occurs in normovolemic patients with known myocardial damage who are dialyzed for acute uremia when ACD blood prime is used at high initial flow rates (350 c.c. per minute) and when dialysis is performed against low calcium dialysate (2.5 mEq. per liter or less). This study tests the hypotheses that (1) rapid transfusion of as little as one unit of CPD blood causes a significant reduction in ionized calcium, (2) the depressive effect of CPD blood is significant and similar to that of ACD blood, (3) rapid blood transfusion (ACD or CPD) is safe if calcium is given simultaneously, (4) addition of calcium to the extracorporeal heparinized blood prime used in dialysis prevents initial depression, and (5) hemodynamic instability during dialysis is prevented when the dialysate is normocalcemic. From the results of our study, we made the following conclusions: (1) Ionized calcium is reduced significantly by rapid transfusion of CPD blood; (2) acute myocardial depression noted with CPD blood is similar to that previously observed with ACD blood and is prevented during transfusion of either type of blood by simultaneous calcium administration; and (3) hemodialysis in patients who have had cardiac surgery is safe if calcium is added to blood prime and dialysate is made normocalcemic.

Steady-state passive hyperventilation alkalosis produces a predictable increase in oxygen uptake (VO2) proportional to the change in arterial pH (pHa) while variable changes in VO2 have been reported during alkali infusion. To compare metabolic with respiratory alkalosis 17 dogs were anesthetized with halothane and their VO2 response to respiratory alkalosis evaluated by hyperventilation. The pHa measured during this phase was duplicated during the later continuous infusion of NaHCO3 at which time either 1) ventilation was held constant at the control level, allowing arterial carbon dioxide tension (PaCO2) to rise as a consequence of the bicarbonate dissociation, or 2) PaCO2 was held constant by servo control of ventilation. Hyperventilation (pHa 7.6, PaCO2 13 Torr) produced an average increase in VO2 of 24%. During the bicarbonate infusion at constant ventilation (pHa 7.6, PaCO2 45 Torr) VO2 increased only 7%; however, when PACO2 was held constant by servo ventilation VO2 increased 21% above control. We conclude that respiratory and metabolic alkalosis produce similar increases in VO2 when steady-state acid-base conditions are achieved.

Total cardiopulmonary bypass separates the lungs from the pulmonary arterial circulation. Continued ventilation with non CO 2 -containing mixtures during bypass will result in airway hypocapnia. Airway hypocapnia results in decreased compliance, increased work of breathing, and increased resistance to air flow. Reversal of airway hypocapnia increased compliance one-third, decreased work of breathing 20%, and decreased air flow resistance approximately 40% when compared to the values obtained during the period of low airway CO 2 . These changes in airway mechanics must be considered for pulmonary management during cardiac bypass.