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A series of six shock initiation experiments have been carried out on low density LX-14 powder in order to simulate a shock insult on the heavily damage polymer bonded explosive, LX-14. Two distinct morphologies were studied (tap density molding powder and machined swarf), both at the same density of 0.942 [Formula: see text], or 50.1% theoretical maximum density. The purpose of these experiments was to provide data to help make an assessment of the effects that damage has on the material sensitivity to a planar shock. This was achieved primarily by providing shock sensitivity data in the form of a Pop plot, and also reactants equation of state data, which aids in the determination of input conditions for both the experiments performed in this work and also future experiments of this material type. The experiments were of a cut-back format, consisting of four sample heights on each shot and diagnosed with optical velocimetry. The experiments were carried out at the Technical Area 40 Chamber 9 gas gun facility at the Los Alamos National Laboratory, where the LX-14 targets were subjected to Al 6061 and Oxygen Free High Conductivity copper impactors launched to velocities up to 2.14 km/s. Time corrected reactive growth wave profiles are presented in this paper along with the derivation of the following Hugoniot parameters for this explosive, where the molding powder and machine swarf are represented by the following linear equations, respectively, [Formula: see text] and [Formula: see text]. The results show that the steady increase in shock sensitivity with increasing void fraction reaches an inflection point beyond which the shock sensitivity begins to decease. This inflection point lies between 65% and 50% of the theoretical maximum density of the LX-14. In both cases, the damaged LX-14 was not as sensitive as expected, with a relative shock sensitivity of the molding powder being less than the pressed LX-14, and the machined swarf having a shock sensitivity that is comparable to pressed LX-14.

Taylor wave spall experiments were conducted on annealed copper targets using direct explosive loading. The targets were mounted on the back of an explosive disc which was being used for a shock to detonation transition (SDT) test in a gas gun. This technique allows two experiments to be conducted with one piece of explosive. Explosive loading creates a high stress state within the target with a lower strain rate than an equivalent plate impact experiment, although the shock front will also have some curvature. Three shots were performed on two differently annealed batches of copper to investigate the viability of the technique and the effect of annealing on the spall response. One pair of targets was annealed at 850°C for four hours and the other target was annealed at 600°C for one hour. The free surface velocity (FSV) profiles were recorded using a Photonic Doppler Velocimetry (PDV) probe focused on the center of the target. The profiles were compared to predictions from the CREST reactive burn model. ...

We investigate the applicability of using digital PCR to estimate absolute limits of detection and quantitation associated with the validation of traditional real-time PCR methods for analysis of genetically modified (GM) ingredients. We also demonstrate the use of dynamic arrays as a precursor in selecting suitable sample dilution levels for accurate copy number assessment using the aforementioned digital PCR. Additionally, we further explore the relevance of digital PCR in accurately quantifying plasmid copy numbers associated with a commercially available Certified Reference Material. The use of digital PCR has the advantage of facilitating absolute single molecule detection, therefore negating the necessity for standards on a calibration curve, and reducing associated matrix effects. The approaches described in this paper enable pre-existing validated protocols to be re-examined, and estimates based on an alternative approach using digital PCR to be used in order to objectively characterise sensitivity limits.

Silicon nano-crystalline structures have been prepared from amorphous silicon films on silicon substrates using direct-current plasma hydrogenation and annealing at temperatures about 450 °C. Plasma power densities about 5.5 W/cm 2 were found to be suitable for the creation of nano-porous layers. The nano-porous structures produced visible luminescence at room temperature as confirmed by photoluminescence spectroscopy. The effects of plasma power and annealing temperature on the grain size and luminescence properties of these layers have been investigated by scanning electron microscopy, transmission electron microscopy, Fourier transform infrared spectroscopy and photoluminescence. Lowering the temperature during the hydrogenation step led to an increase in the diameter of the grains. In addition, lowering the plasma power density caused the distribution of the porous surface structures to become less widely distributed and the formation of more packed structures resulted.

Superconducting hot-electron bolometer (HEB) mixers are promising heterodyne detectors for THz frequencies. HEB mixers operating at 4 K or below offer the possibility of near-quantum-limited performance without an upper frequency limit imposed by the superconducting energy gap. High temperature superconductor HEB mixers offer very sensitive, low power heterodyne detectors operating at temperatures approaching 90 K for applications requiring closed-cycle refrigeration. We report on recent progress in fabricating and characterizing high-T/sub c/ mixers based on ultra-thin (10-20 nm) YBa/sub 2/Cu/sub 3/O/sub 7-/spl delta// films patterned to submicrometer dimensions (0.1-1 /spl mu/m) and incorporated into 1-3 THz planar mixer circuits.

Superconducting hot-electron bolometers (HEB) represent a promising candidate for heterodyne mixing at frequencies exceeding 1 THz. Nb HEB mixers offer performance competitive with tunnel junctions without the frequency limit imposed by the superconducting energy gap. Although the performance of YBa/sub 2/Cu/sub 3/O/sub 7-/spl delta// HEB mixers is not projected to be superior to that of Nb devices, which operate at low temperatures, they introduce the possibility of sensitive, low power heterodyne detectors operating at temperatures approaching 90 K for applications requiring portability and closed-cycle refrigeration. We report on the fabrication and characterization, both DC and RF, of high-T/sub c/ mixers based on ultra-thin (/spl les/20 nm) YBa/sub 2/Cu/sub 3/O/sub 7-/spl delta// films patterned to micrometer dimensions and incorporated into 2.5 THz planar mixer circuits.

Pigeonpea (Cajanus cajan) is an important subsistence crop in India where traditional landraces and improved hybrids are grown alongside each other. Gene flow may result in genetic erosion of these landraces and their wild relatives, whilst transgene escape from future genetically engineered varieties is another potential hazard. To assess the impact of these factors gene flow needs to be measured. A set of 10 simple sequence repeat markers have been developed, which exhibit polymorphism across a range of pigeonpea varieties. Use of these markers also offers an efficient system for the assessment of genetic diversity within populations of pigeonpea.

Treatment of vascular endothelial cells with inflammatory cytokines stimulates surface expression of E-selectin (previously known as endothelial-leukocyte adhesion molecule-1) and promotes the transendothelial migration of neutrophils. To assess participation of E-selectin in cytokine-mediated neutrophil migration, an in vitro model consisting of monolayers of human umbilical vein endothelial cells (HUVEC) grown on amniotic connective tissue was used. When HUVEC-amnion cultures were stimulated for 4 h with relatively low concentrations of IL-1 (0.1 to 0.15 U/ml), mAb BB11 or H18/7 to E-selectin partially inhibited migration of subsequently added neutrophils. However, when the cultures were stimulated with 15 U/ml of IL-1 for 4 or 24 h, little to no inhibition was observed. mAb to E-selectin also failed to inhibit migration of neutrophils across HUVEC-amnion cultures treated with low doses of IL-1 when the leukocytes were additionally stimulated by the chemoattractant leukotriene B4. In contrast, migration of neutrophils across IL-1-treated HUVEC was profoundly inhibited by mAb to CD11/CD18 leukocytic integrins under all conditions tested. Results of these studies suggest that participation of E-selectin is not essential for migration of neutrophils across cytokine-stimulated HUVEC in vitro; rather, E-selectin can be bypassed in favor of CD11/CD18-dependent mechanisms under appropriate circumstances.

A T=100 mK, la resistivite augmente de plus d'un facteur 1000 dans H=8 T. La resistivite reste lineaire a E>30 mV/cm. Les donnees sont coherentes avec un saut avec une certaine influence des interactions coulombiennes, mais pas avec une cristallisation de Wigner ou des ondes de densite chargees

To compare selected characteristics in two North Carolina counties to document women's health services at the geographical extremes of the state.Using aggregated 2004 data obtained from the North Carolina State Center for Health Statistics, obstetric and perinatal characteristics were experimentally analyzed for the westernmost and easternmost counties in North Carolina (Cherokee and Dare County, respectively).During the experiment period, 489 infants were delivered in Dare County (population 33,518), while 259 births were recorded in Cherokee County (population 25,289). Prenatal care was established by most women in both counties by the second gestational month. Women in Cherokee County were younger and less educated at delivery than women in Dare County, and smoking prevalence was higher in Cherokee County than in Dare County (31.3% vs 12.9%; p0.01). Cherokee County infants required assisted ventilation and other medical interventions more often than babies born in Dare County (p0.01) yet significantly fewer cesarean deliveries were performed in Cherokee County than Dare County (25.5% vs 35.2%; p = 0.04).This pilot study showed a significantly higher rate of tobacco use, and lower maternal education level in Cherokee County was associated with a higher incidence of multiple maternal complications and neonatal interventions compared to Dare County. Interestingly, the cesarean delivery rate was lower in Cherokee County despite these factors. We found10% of babies born in the study regions required any neonatal intervention. Early and almost universal access to prenatal care did not appear to be a problem at either site. Our preliminary comparison identified important limitations in this government-sponsored dataset that rendered logistic regression analysis methodologically impossible. Changes in process could improve surveillance based on patient-level data and facilitate multivariate analysis. Specific interventions to optimize women's health services form the basis of future experimental research, including larger regional populations.

In order to study the SDT process in a granular non‐ideal explosive (NIE) an experimental technique has been developed that allows the granular explosive to be shock initiated at a well controlled “tap density”. The granular NIE was contained in a PMMA cone and a planar shock was delivered to the explosive through a buffer plate of varying material. A combination of piezoelectric probes, ionisation pins, PVDF stress gauges and a high speed framing camera were used to measure the input shock pressure and shock and detonation wave positions in the explosive. Four trials were performed to characterise the run to detonation distance versus input pressure relationship (Pop plot) of the granular NH4 NO3 based explosive. Input pressures ranged from close to the 4 GPa predicted CJ pressure of the granular explosive down to 1.4 GPa, giving run distances up to ∼12 mm for the lowest pressure. The data indicates a steady acceleration of the input shock to detonation velocity, implying significant reaction growth at t...

The Dual-Axis Radiographic Hydrodynamics Test (DARHT) facility will employ two perpendicular electron linear induction accelerators to produce intense, bremsstrahlung X-ray pulses for flash radiography. We intend to produce measurements containing three-dimensional information with sub-millimeter spatial resolution of the interior features of very dense, explosively driven objects. The facility will be completed in two phases with the first phase having become operational in July 1999 utilizing a single-pulse, 20 MeV, 2 kA, 60 ns accelerator, a high-resolution electrooptical X-ray imaging system, and other hydrodynamics testing systems. We describe this machine and discuss its current operating status. The first electron beams will be generated in the second phase of DARHT this year. The second DARHT accelerator consists of a 18.4 MeV, 2 kA, 2-microsecond pulse-width accelerator. Four short electron micropulses of variable pulse-width and spacing will be chopped out of the original, long accelerator pulse for producing time-resolved X-ray images. The second phase also features an extended, high-resolution electro-optical X-ray system with a framing speed of about 2 MHz. We discuss this accelerator by summarizing the overall design of the long-pulse injector and accelerator as well as some component test results. We also discuss the fast kicker used to separate the long-pulse beam into short bursts suitable for radiography.

The Dual-Axis Radiographic Hydrodynamics Test (DARHT) facility will employ two perpendicular electron linear induction accelerators to produce intense, bremsstrahlung X-ray pulses for flash radiography. The first DARHT accelerator became operational in July 1999 producing a single electron beam pulse at 20 MeV, 2 kA, and 60 ns pulse. The second DARHT accelerator consists of a 18.4 MeV, 2 kA, 2 microsecond pulse-width accelerator. Four short electron micropulses of variable pulse-width and spacing will be chopped out of the original, long accelerator pulse for producing time-resolved X-ray images. The first electron beam in this machine will be produced this year. We discuss the pulsed power systems associated with this machine. These include an injector driven by a Marx consisting of 88 type-E PFN stages driving a matched load at 3.2 MV with a 500 ns risetime, 2 microsecond e-beam pulse. The Metglas-filled induction cells making up the accelerator are described. Each induction cell is driven by a cell-driver that contains 4, 7-section E-network PFNs in a Marx configuration with a 20 /spl Omega/ impedance that delivers flattop of greater than 2 microseconds into a resistive load of 5 /spl Omega/ for a total drive current of 10 kA at 200 kV. The principal element of the electron beam transport system is the fast deflector, or kicker, used to generate four micropulses from the primary beam. The kicker modulator generates bi-polar 18 kV pulses of arbitrary pulse width and spacing using solid-state circuitry that is described. Component test data from the injector, accelerator, and kicker system is discussed.

Backcross breeding with marker-assisted selection was used to construct an intervarietal set of part chromosome substitution lines in Brassica napus, formed from a cross between two winter varieties of oilseed rape: Tapidor and Victor. A total of 22 lines from this substitution library were examined over a 3-year period, in a total of nine field trials, for seed oil fatty acid composition and seed oil content. Trialing of the substitution lines gave evidence for the existence of 13 quantitative trait loci (QTL). All 13 QTL affected fatty acid composition of the seed, and were distributed among linkage groups 1, 3, 6, 7, 8, 11, 13, 14, 18, and 19. Seven of these QTL, on linkage groups 3, 6, 8, 13, 14, 18, and 19, also affected total seed oil content. The positions of these QTL are compared to those in the published literature and with respect to erucic acid QTL previously identified in a backcross population of the same cross. The substitution line approach gives increased precision and sensitivity for QTL mapping compared to other methods.

The mechanical and magnetic alignment of the first eight induction-cell, solenoid magnets of the Integrated Test Stand (ITS) for the Dual-Axis Radiographic Hydrodynamic Test (DARHT) facility were measured by observing the deflection of a fine, taut wire carrying a pulsed current. To achieve the required alignment (less than 0.25 mm offset and less than 5 mrad tilt), the magnet design uses quadrufilar windings and iron field-smoothing rings. After detailed measurements of each solenoid magnet, the cells are assembled and then mechanically aligned using a laser and an alignment target moved along the cell centerline. After the cells are in final position, the pulsed wire method is used to verify the magnetic alignment. The measurements show an average offset of the magnetic axes from the mechanical axis of 0.15 mm, with a maximum offset of 0.3 mm. The average tilt of the magnetic axes was 0.7 mrad with a maximum tilt of 1.4 mrad. Tilts are corrected to less than 0.3 mrad, using dipole trim magnets assembled into each cell. Correction is limited by power supply resolution and by background noise. >

The PHERMEX (Pulsed High-Energy Radiographic Machine Emitting X-rays) standing-wave linear accelerator is a high- current electron beam generator used for flash-radiography. An improved electron gun has been designed employing a flat-thermionic cathode to replace the existing Pierce-geometry gun. The flat cathode yields increased current with the same applied voltage and cathode area as the Pierce gun. The ISIS code simulations indicate a beam current of 1.5 kA at 600 kV vs. 500 A for the old gun. The new geometry also reduces the probability for high voltage breakdown in the A-K gap. A re-entrant magnet captures the expanding electron beam and a bucking coil nulls cathode-fringe field. A third coil is used to optimize the extraction field profile and reduce the effect of nonlinear space charge on the beam emittance. Time-resolved measurements of beam current and voltage have been made. In addition, a streak camera was used to measure beam emittance and spatial profile. Comparisons of measurements with simulations are presented. >

The Dual-Axis Radiographic Hydrodynamics Test (DARHT) facility will employ two perpendicular electron Linear Induction Accelerators to produce intense, bremsstrahlung x-ray pulses for flash radiography. We intend to produce measurements containing three-dimensional information with sub-millimeter spatial resolution of the interior features of very dense, explosively-driven objects. The facility will be completed in two phases with the first phase having become operational in July 1999 utilizing a single-pulse, 20-MeV, 2-kA, 60-ns accelerator, a high-resolution electro-optical x-ray imaging system, and other hydrodynamics testing systems. We will briefly describe this machine. The first electron beams will be generated in the second phase of DARHT this year. The second DARHT accelerator consists of a 18.4-MeV, 2-kA, 2-microsecond pulse-width accelerator. Four short electron micropulses of variable pulse-width and spacing will be chopped out of the original, long accelerator pulse for producing time-resolved x-ray images. The second phase also features an extended, high-resolution electro-optical x-ray system with a framing speed of about 2-MHz. We will discuss this accelerator by summarizing the overall design of the long-pulse injector and accelerator. We will also discuss the fast kicker used to separate the long-pulse beam into short bursts suitable for radiography.

We describe the fabrication of a free‐standing YBa2Cu3C7−δ air bridge for useful applications of microstructures and microcircuits integration. We have used a sacrificial dielectric layer, which was subsequently etched, to produce the air gap between top and bottom layers. We have used conventional photolithographic processing, ion‐beam dry etching, and selective wet etching with HF to create the novel microstructures. Step coverage of epitaxial bridge layers have been achieved without significant degradation of the superconducting properties of YBa2Cu3O7−δ layers.

The elimination kinetics of ethylene glycol (EG) in human subjects treated with fomepizole (4-methylpyrazole) were analyzed to establish the efficacy of alcohol dehydrogenase (ADH) inhibition and to characterize elimination pathways.Drug concentration data from patients enrolled in the EG arm of the Methylpyrazole for Toxic Alcohols trial, a prospective, multicenter, open-label trial of fomepizole, were analyzed and compared with published estimates.In 19 patients analyzed (EG concentrations of 3.5 to 211 mg/dL), elimination was first order during fomepizole monotherapy (half-life of 19.7+/-1.3 hours) and was not affected by the presence of ethanol. The elimination rate was significantly faster (half-life of8.6+/-1.1 hours, P.001) in the absence of fomepizole and ethanol. EG elimination by the kidneys was directly proportional to remaining renal function as estimated by creatinine clearance, with a fractional excretion of 25.5%+/-9.4%. Renal elimination and hemodialysis were the only significant routes of EG elimination as long as fomepizole concentrations were maintained well above 10 micromol/L (EG/fomepizole molar ratio,100:1). All patients with normal serum creatinine concentrations at the initiation of fomepizole treatment had rapid rates of renal elimination (half-life of 16.8+/-0.8 hours).At doses used, fomepizole effectively inhibits ADH-mediated metabolism of EG. Serum creatinine concentration at presentation and creatinine clearance can be used to predict EG elimination during fomepizole therapy and can help determine which patients will require hemodialysis to expedite EG elimination. An absolute EG concentration above 50 mg/dL should no longer be used as an independent criterion for hemodialysis in patients treated with fomepizole.

The Dual-Axis Radiographic Hydrodynamics Test (DARHT) facility will use two perpendicular electron linear induction accelerators to produce intense, bremsstrahlung X-ray pulses for flash radiography. We intend to produce measurements containing 3D information with sub-millimeter spatial of the interior features of very dense explosively driven objects. The facility will be completed in two phases with the first operational by June 1999 utilizing a single-pulse, 19.8-MeV, 2 to 4-kA, 60-ns accelerator (activated in March 1999), a high-resolution electro-optical X-ray imaging system, and other hydrodynamics testing systems. The second phase will be operational by Sept. 2002 and features the addition of a 20-MeV, 2 to 4-kA, 2-microsecond accelerator. Four short electron micropulses of variable pulse-width and spacing will be chopped out of the original, long accelerator pulse for producing time-resolved X-ray images. The second phase also features an extended, high-resolution electro-optical X-ray system with a framing speed of about 2-MHz. In this paper we present a Figure-Of-Merit for a X-ray based flash radiography system to motivate the selection of accelerator parameters. We will then present sub-system performance measurements from Phase 1, the physics of the interaction of our high-intensity beams with the X-ray conversion target, initial Phase 1 accelerator measurements (if available), and plans for operation. We will also discuss designs and prototype testing results for the 2-microsecond Phase 2 accelerator, including prototype induction cells and pulsed power, prototype kicker magnet performance to chop the beam, and design considerations for a multipulse X-ray conversion target.

We describe the clinical course of two patients who developed acute pneumonitis followed by reactive airways dysfunction syndrome after bathing in a hot tub. Additional findings were present and suggested that exposure to a corrosive agent was responsible. Bromine and hydrobromic acid generated from a widely used water disinfectant were implicated as the underlying cause. Physicians should be alert to the possibility that such exposures may initiate or exacerbate inflammatory pulmonary disease.

Septic arthritis is the most important diagnosis to consider in patients presenting with acute monarticular arthritis. We present the case of an eight-year-old girl who developed a Pseudomonas aeruginosa and Klebsiella pneumoniae septic arthritis of her knee following an injury with a marine sea shell. After treatment with antibiotics and arthroscopic irrigation, she had good functional recovery. We could find no previously reported cases of Pseudomonas aeruginosa or Klebsiella pneumoniae septic arthritis resulting from an injury in a marine environment. The pathogenesis and treatment of septic arthritis and infection following marine injuries are discussed.

Los Alamos has designed and proposes to establish an XUV-IR free-electron laser (FEL) user facility for scientific research and industrial applications based on coherent radiation ranging from soft x rays as short as 1 nm to far-infrared wavelengths as long as 100 micrometers . As the next-generation light source beyond low-emittance storage rings with undulator insertion devices, this proposed national FEL user facility should make available to researchers broadly tunable, picosecond-pulse, coherent radiation with 104 to 107 greater spectral flux and brightness. The facility design is based on two series of FEL oscillators including one regenerative amplifier. The primary series of seven FEL oscillators, driven by a single, 1-GeV rf linac, spans the short-wavelength range from 1 to 600 nm. A second 60-MeV rf linac, synchronized with the first, drives a series of three Vis/IR FEL oscillators to cover the 0.5 to 100-micrometers range. This paper presents the motivation for such a facility arising from its inherently high power per unit bandwidth and its potential use for an array of scientific and industrial applications, describes the facility design, output parameters, and user laboratories, makes comparisons with synchrotron radiation sources, and summarizes recent technical progress that supports the technical feasibility.

Thin film nanocrystalline porous silicon layers have been fabricated from amorphous silicon films using dc plasma hydrogenation and subsequent annealing at temperatures about 450°C on silicon substrates. Plasma power densities about 5.5W∕cm2 were found to be suitable for etching of the silicon film and the creation of nanoporous layers. The nanoporous structures show visible luminescence at room temperature as confirmed by photoluminescence spectroscopy. The effects of plasma power and annealing temperature on the grain size and luminescence properties of these layers have been investigated by scanning electron microscopy, transmission electron microscopy, photoluminescence, and cathodoluminescence. It was observed that by lowering the temperature during the hydrogenation step, the diameter of the grains increased, whereas lowering the plasma power density caused the distribution of the porous surface structures to become less widely distributed and the formation of more packed structures. In addition, in...

The toxin A chain of ricin has been conjugated by a disulfide bond to a murine monoclonal antibody that recognizes the gp67kD antigen present on 95% of peripheral T lymphocytes. The immunotoxin retains both functions of its component parts: it binds to human peripheral blood lymphocytes, and it inhibits protein synthesis in a cellfree reticulocyte system. The immunotoxin has been evaluated for its ability to inhibit in vitro T lymphocyte transformation. In the presence of 20 mM NH4Cl, the immunotoxin decreases lymphocyte proliferation in response to phytohemagglutinin to less than 8% of untreated controls. The proliferative response in mixed lymphocyte culture and the development of allocytotoxic T cells is also dramatically inhibited by this immunotoxin. Monoclonal antibody alone does not inhibit these responses. Specificity of the immunotoxin has been established: the effect of the immunotoxin can be blocked by unconjugated monoclonal antibody, but not by a control monoclonal antibody that recognizes another T lymphocyte differentiation antigen or by a control monoclonal antibody that does not recognize human peripheral blood leukocytes. Treatment of human bone marrow cells with the immunotoxin preserves hematopoietic progenitor cells, as measured by granulocyte-macrophage, erythroid, and multipotential hematopoietic progenitor cell assays. These results indicate that an anti-pan T lymphocyte-ricin A chain immunotoxin is an effective agent against immunocompetent T lymphocytes in vitro, and may be an effective agent for use in clinical bone marrow transplantation.

NASA Space Station missions will include crewmembers who are highly experienced in the use of the Space Station computer system, as well as others who are novices. Previous research into novice-expert differences has strongly implied that user interface changes that aid novices tend to impair experts and vice versa. This experiment investigated the impact reformatting alphanumeric information on current Space Shuttle computer displays had on the speed and accuracy of experts and nonexperts in two different search tasks. Large improvements in speed and accuracy were found for nonexperts on the reformatted displays. Experts had fewer errors but no response time difference on the reformatted displays. Differences in expert and nonexpert search strategies and implications for the design of computer displays are discussed.

We have designed, calibrated, and deployed an electron spectrograph to measure the effect of the free‐electron laser interaction on the relativistic electron beam in an FEL. The spectrograph spans a wide energy range (ΔE/E∼1) and is designed for electron energies from 2 to 4 MeV. Calibration was achieved using a 2–6‐keV proton beam, and the measured dispersion is in good agreement with the value predicted from ray tracing. The spectrograph has been used to estimate the extraction efficiency, and the results agree within 25% with the observed microwave power levels.

The relative rates of penetration of pentoses and hexoses into human blood platelets were studied with a photoelectric densimeter. It was concluded that pentoses enter human platelets by free diffusion whereas hexoses penetrate into these cells by an altered diffusion process.

A computer aided testing (CAT) system for semiconductor injection lasers featuring data base management functions and real time system monitor is described. A mini-computer utilizing a factory data link and data collection software is configured in a network to link testing and burn-in systems. A data base design that models the chronological flow of product through the laser production process was developed to meet the specific data retrieval requirements of the product engineering organization. Specific features of this data collection and retrieval system are discussed.A computer aided testing (CAT) system for semiconductor injection lasers featuring data base management functions and real time system monitor is described. A mini-computer utilizing a factory data link and data collection software is configured in a network to link testing and burn-in systems. A data base design that models the chronological flow of product through the laser production process was developed to meet the specific data retrieval requirements of the product engineering organization. Specific features of this data collection and retrieval system are discussed.