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The performance of programmable voltage signals that exploit the quantum behavior of superconducting Josephson junctions continues to improve and enhance measurements in metrology, communications, and quantum control. We review advances in pulse-driven digital synthesis techniques with Josephson-junction-based devices. Quantum-based synthesis of voltage waveforms has been demonstrated at frequencies up to 3 GHz and rms amplitudes up to 4 V. Josephson pulse generators have also been used to control and characterize superconducting qubits. [ABSTRACT FROM AUTHOR]

We demonstrate Josephson arbitrary waveform synthesizers (JAWS) with increased operating temperature range for temperatures below 4 K. These JAWS synthesizers were fabricated with externally-shunted Nb/ a -Si/Nb junctions whose critical current exhibits improved temperature stability compared to the self-shunted Nb/Nb 0.15 Si 0.85 /Nb junctions typically used. Vertical stud resistors made of 230 nm of PdAu were developed to provide the milliohm shunt resistance required for junction overdamping while maintaining a small footprint suitable for high-density series arrays embedded in a coplanar waveguide. We evaluated the performance of these resistors from 3.8 K down to 20 mK. We designed, fabricated and tested a JAWS circuit with 4650 externally shunted Nb/ a -Si/Nb JJs with a critical current density ( J c ) of 0.12 mA ∕ μ m 2 and critical current ( I c ) of 3 mA. This circuit was designed to be mounted to the 3 K stage of a dilution refrigerator and used to control and calibrate a qubit mounted at the 10 mK stage. To increase the circuit density of the JAWS circuits we made arrays of two-junction vertical stacks. Current-voltage ( I - V ) curves of this JAWS circuit with stacked junctions under microwave excitation show Shapiro steps with quantum-locking ranges similar to those of JAWS circuits used for qubit control.

Scaling of quantum computers to fault-tolerant levels relies critically on the integration of energy-efficient, stable, and reproducible qubit control and readout electronics. In comparison to traditional semiconductor-control electronics (TSCE) located at room temperature, the signals generated by rf sources based on Josephson-junctions (JJs) benefit from small device sizes, low power dissipation, intrinsic calibration, superior reproducibility, and insensitivity to ambient fluctuations. Previous experiments to colocate qubits and JJ-based control electronics have resulted in quasiparticle poisoning of the qubit, degrading the coherence and lifetime of the qubit. In this paper, we digitally control a 0.01-K transmon qubit with pulses from a Josephson pulse generator (JPG) located at the 3-K stage of a dilution refrigerator. We directly compare the qubit lifetime T 1 , the coherence time T 2 * , and the thermal occupation P th when the qubit is controlled by the JPG circuit versus the TSCE setup. We find agreement to within the daily fluctuations of ±0.5 μ s and ±2 μ s for T 1 and T 2 * , respectively, and agreement to within the 1% error for P th . Additionally, we perform randomized benchmarking to measure an average JPG gate error of 2.1 × 10 -2 . In combination with a small device size ( < 25 mm 2 ) and low on-chip power dissipation (≪100 μ W), these results are an important step toward demonstrating the viability of using JJ-based control electronics located at temperature stages higher than the mixing-chamber stage in highly scaled superconducting quantum information systems.

On March 24 and 25, 2017 researchers and clinicians from around the world met at Temple University in Philadelphia to discuss the current knowledge of Mycobacterium avium ssp. paratuberculosis (MAP) and its relationship to human disease. The conference was held because of shared concern that MAP is a zoonotic bacterium that poses a threat not only to animal health but also human health. In order to further study this problem, the conferees discussed ways to improve MAP diagnostic tests and discussed potential future anti-MAP clinical trials. The conference proceedings may be viewed on the www.Humanpara.org website. A summary of the salient work in this field is followed by recommendations from a majority of the conferees.

The influence of stimulus parameters on compound muscle potentials evoked by transcranial magnetic double stimulation was systematically investigated. Two magnetic stimulators were discharged via a figure-of-eight-shaped magnetic coil (outer diameter of each circular coil, 7 cm) over the left hemisphere, 6 cm lateral to Cz, using a Bistim interface. Recordings were made from the right first dorsal interosseus muscle. In experiment I, in 12 healthy volunteers the intensity of the conditioning subthreshold stimulus was varied from 0 to 100% of the relaxed motor threshold at an interstimulus interval of 1 ms. In experiment II, interstimulus intervals of 1, 3 and 5 ms were used to investigate the effect of conditioning stimuli of 3 fixed intensities. Maximal reduction of the amplitude of motor evoked potentials was found at a conditioning stimulus intensity of 65% of the relaxed motor threshold (and at an interstimulus interval of 1 ms). Because intensities of the conditioning stimulus higher than 65% reduced amplitudes of motor evoked potentials less effectively than at this intensity, refractoriness of pyramidal neurons can be ruled out as the main mechanism contributing to the observed inhibition. Activation of inhibitory interneurons by intensities lower than is necessary to activate pyramidal neurons is discussed as a possible mechanism for the inhibitory effects evoked by transcranial magnetic stimulation.

The purpose of this study is to describe the physical configuration of disposable and reusable absorbent products and relate composition and construction to efficacy in the management of urinary incontinence in patients with burn injuries. The basic structure of a wearable absorbent product consists of three layers: a fluid-impermeable backing sheet, a fluid-pervious coverstock on the body-contacting surface, and an interposed absorbent core. The biomechanical performance of these absorbent products was determined by measuring the total absorbent capacity, defined as the maximum amount of liquid held by the product as a whole. On the basis of the results of this study, absorbent products are recommended for the incontinent patient with burns.

The purpose of this study was to determine the biomechanical performance of commercially available underpads and bed linens to reduce the development of pressure sores in patients with burns who are at high risk. The three biomechanical performance parameters examined were coefficient of friction, absorbent capacity, and rewet. Because wetting either cotton or cotton/polyester bedsheets markedly increases their coefficients of friction, underpads should be used routinely to protect the skin against frictional forces. One disposable underpad is ideally suited to protect the skin of the patient at high risk. It has a polyolefin backing with a low coefficient of friction that serves as an effective barrier to moisture transmission while still shifting easily with the patient's movement. In addition, it is the only underpad studied that contains a superabsorbent polymer that provides a far superior absorbent capacity and minimizes rewet. Wet-back is further inhibited by its thick intermediate tissue layer and its spunbonded polypropylene coverstock.

Smart-looking clothes have been designed for wheelchair users. These clothes make dressing faster and easier, and the clothes fit better than the standard garments. The special features for new adaptive clothing for wheelchair users include easy handling fastenings, quick-access garment openings, conveniently placed pockets, custom-curved trousers, slacks, and jackets, custom-shaped dresses and skirts, ponchos or custom-made coats, easy-fit undergarments, and durable styled fabrics. These clothing adaptations are attractive and give the wearer and the observer the feeling that the person with the disability is not set apart by the clothing he or she wears.

The rabbit homolog to the locus control region (LCR) of the human beta-like globin gene cluster was isolated, and long segments containing the DNase I hypersensitive sites (HS) were sequenced. The order and spacing of HS4, HS3, HS2 and HS1 are conserved between rabbit and human. Alignment of these sequences with their homologs from human, goat, and mouse shows that very long segments of DNA match between species, for over a thousand base pairs on either side of the previously identified functional cores, indicating that some important functions are found outside the cores. The activity of rabbit HS2 and HS3 was tested by attaching each to a novel reporter gene constructed by inserting the luciferase coding region into the rabbit epsilon-globin gene. In contrast to previous reports showing no effect of human or mouse HS3 on transient expression, both the rabbit HS2 and HS3 DNA fragments separately increased transient expression from the epsilon-luciferase hybrid gene and expression from stably integrated constructs in K562 erythroleukemia cells.

An outbreak of histoplasmosis estimated to involve more than 100,000 residents in Indianapolis, Indiana, occurred between September 1978 and August 1979. In the 435 cases evaluated, 52% of the patients were between 15 and 34 years old, and 63% were black. Fifteen patients died, and 46 progressive disseminated infection. Twenty-four patients had pericarditis, and 26 had rheumatologic syndromes. Unusual manifestations that occurred in 18 patients included esophageal and vocal cord ulcers, parotitis, adrenal insufficiency, uveitis, fibrosing mediastinitis, interstitial nephritis, intestinal lymphangiectasia, and epididymitis. The highest attack rate was in the central part of the city, which is a densely populated, disproportionately black section. The source of the outbreak has not been proved by positive culture results; two sites, however, were suspected on an epidemiologic basis.

Performances of participants for the detection and measurement of rheumatoid factor on 18 consecutive CAP survey specimens are tabulated. All reagents used by participants performed well qualitatively on the positive and negative specimens. Quantitation of positive specimens by titer and International Units demonstrated prominent interlaboratory variance.

Available knowledge is adequate to ameliorate the drift of children in foster care. The problem is the lag in use of that knowledge in practice. This article offers a framework for training workers and supervisors to achieve permanency goals.

The participant performances on the College of American Pathologists (CAP) Urine Survey specimens distributed during 1979 and 1980 for pregnancy testing are reviewed. Almost all the reagent methods used by the participants performed well on the negative specimens. Prominent differences in results on the positive specimens were found. Awareness by laboratorians of the reagent sensitivity, limitations, and capabilities of commercial tests for determining human chorionic gonadotropin in urine is recommended.

Equine anti-human lymphoblast globulin (MAG) used in combination with other immunosuppressive agents did not impair chemotaxis, phagocytosis, nitroblue tetrazolium (NBT) reduction or halogenation by peripheral blood neutrophils (PMN) from seven human recipients of cadaver renal allografts. MAG was given to the allograft recipients following transplantation, and the dosage was determined each day by quantitation of peripheral blood T and B lymphocytes. No deposition of immunoglobulin or complement on the recipient's PMN was detected by indirect immunofluorescence. Chemotaxis of PMN was determined in blind-well chambers, and phagocytosis of opsonized zymosan was quantitated by spectrophotometric measurement of solubilized formazan, and halogenation was measured by quantitating the incorporation of 125I into PMN that had phagocytosed opsonized zymosan. Chemotaxis, phagocytosis, NBT reduction, and halogenation by neutrophils from patients receiving MAG, prednisone and azathioprine were not impaired.

We describe a technic that measures the kinetics of the metabolic burst of peripheral blood neutrophils (PMN) by electron spin resonance (ESR) spin trapping. Using this technic, a functional assay for the kinetics of the alternate pathway complement cascade is developed. PMN were stimulated by phagocytosis of opsonized zymosan (OpZym) to undergo the metabolic burst and the resulting free hydroxyl radicals generated during the burst were trapped using 5,5-dimethyl-1-pyrroline-N-oxide (DMPO) to form a stable spin adduct. Rapid sequential measurements of the spin adduct concentration were made using a computer-controlled ESR spectrometer to follow the time course of the metabolic burst. Differences in the results obtained with OpZym and with PMN incubated with unopsonized zymosan (Zym) and serum yields information about the kinetics of opsonization. The kinetics of the alternate complement pathway opsonization in sera from normal and C8-deficient patients were compared and found not to be affected significantly by the absence of C8 complement protein.