This Letter presents results from the first fully integrated experiments testing the magnetized liner inertial fusion concept S. A. Slutz et al., Phys. Plasmas 17, 056303 (2010), in which a cylinder ...of deuterium gas with a preimposed 10 Taxial magnetic field is heated by Z beamlet, a 2.5 kJ, 1 TW laser, and magnetically imploded by a 19 MA, 100 ns rise time current on the Z facility. Despite a predicted peak implosion velocity of only 70 km = s, the fuel reaches a stagnation temperature of approximately 3 keV, with T(e) ≈ T(i), and produces up to 2 x 10(12) thermonuclear deuterium-deuterium neutrons. X-ray emission indicates a hot fuel region with full width at half maximum ranging from 60 to 120 μm over a 6 mm height and lasting approximately 2 ns. Greater than 10(10) secondary deuterium-tritium neutrons were observed, indicating significant fuel magnetization given that the estimated radial areal density of the plasma is only 2 mg = cm(2).
Abstract Objective The objective was to develop a clinical practice guideline on the management of neck pain–associated disorders (NADs) and whiplash-associated disorders (WADs). This guideline ...replaces 2 prior chiropractic guidelines on NADs and WADs. Methods Pertinent systematic reviews on 6 topic areas (education, multimodal care, exercise, work disability, manual therapy, passive modalities) were assessed using A Measurement Tool to Assess Systematic Reviews (AMSTAR) and data extracted from admissible randomized controlled trials. We incorporated risk of bias scores in the Grading of Recommendations Assessment, Development, and Evaluation. Evidence profiles were used to summarize judgments of the evidence quality, detail relative and absolute effects, and link recommendations to the supporting evidence. The guideline panel considered the balance of desirable and undesirable consequences. Consensus was achieved using a modified Delphi. The guideline was peer reviewed by a 10-member multidisciplinary (medical and chiropractic) external committee. Results For recent-onset (0-3 months) neck pain, we suggest offering multimodal care; manipulation or mobilization; range-of-motion home exercise, or multimodal manual therapy (for grades I-II NAD); supervised graded strengthening exercise (grade III NAD); and multimodal care (grade III WAD). For persistent (>3 months) neck pain, we suggest offering multimodal care or stress self-management; manipulation with soft tissue therapy; high-dose massage; supervised group exercise; supervised yoga; supervised strengthening exercises or home exercises (grades I-II NAD); multimodal care or practitioner’s advice (grades I-III NAD); and supervised exercise with advice or advice alone (grades I-II WAD). For workers with persistent neck and shoulder pain, evidence supports mixed supervised and unsupervised high-intensity strength training or advice alone (grades I-III NAD). Conclusions A multimodal approach including manual therapy, self-management advice, and exercise is an effective treatment strategy for both recent-onset and persistent neck pain.
Magnetizing the fuel in inertial confinement fusion relaxes ignition requirements by reducing thermal conductivity and changing the physics of burn product confinement. Diagnosing the level of fuel ...magnetization during burn is critical to understanding target performance in magneto-inertial fusion (MIF) implosions. In pure deuterium fusion plasma, 1.01 MeV tritons are emitted during deuterium-deuterium fusion and can undergo secondary deuterium-tritium reactions before exiting the fuel. Increasing the fuel magnetization elongates the path lengths through the fuel of some of the tritons, enhancing their probability of reaction. Based on this feature, a method to diagnose fuel magnetization using the ratio of overall deuterium-tritium to deuterium-deuterium neutron yields is developed. Analysis of anisotropies in the secondary neutron energy spectra further constrain the measurement. Secondary reactions also are shown to provide an upper bound for the volumetric fuel-pusher mix in MIF. The analysis is applied to recent MIF experiments M. R. Gomez et al., Phys. Rev. Lett. 113, 155003 (2014) on the Z Pulsed Power Facility, indicating that significant magnetic confinement of charged burn products was achieved and suggesting a relatively low-mix environment. Both of these are essential features of future ignition-scale MIF designs.
Laboratory testing of rocks is traditionally carried out to determine the peak strength using the ISRM Suggested Methods or other suitable standards. However, it is well known that in low-porosity ...crystalline rocks there are at least three distinct stages of compressive loading that can be readily identified if the stress–strain response is monitored during the loading process: (1) crack initiation, (2) unstable crack growth, i.e., crack coalescence and (3) peak strength. Crack initiation is noted as the first stage of stress-induced damage in low-porosity rocks, yet the suggested guidelines of the ISRM for compression tests make no mention of crack initiation. In addition, recent research suggests that crack initiation can be used as an estimate for the in situ spalling strength, commonly observed around underground excavations in massive to moderately jointed brittle rocks. Various methods have been proposed for identifying crack initiation in laboratory tests. These methods are evaluated using ten samples of Äspö Diorite and the results are compared with a simplified method, lateral strain response. Statistically, all methods give acceptable crack-initiation values. It is proposed that the ISRM Suggested Methods be revised to include procedures suitable for establishing the crack-initiation stress.
Biliary Atresia: The Canadian Experience Schreiber, Richard A., MD, FRCP(C); Barker, Collin C., MSc(Epid), MD, FRCP(C); Roberts, Eve A., MD, FRCP(C) ...
The Journal of pediatrics,
12/2007, Letnik:
151, Številka:
6
Journal Article
Recenzirano
Objective To determine the outcomes of Canadian children with biliary atresia. Study design Health records of infants born in Canada between January 1, 1985 and December 31, 1995 (ERA I) and between ...January 1, 1996 and December 31, 2002 (ERA II) who were diagnosed with biliary atresia at a university center were reviewed. Results 349 patients were identified. Median patient age at time of the Kasai operation was 55 days. Median age at last follow-up was 70 months. The 4-year patient survival rate was 81% (ERA I = 74%; ERA II = 82%; P = not significant NS). Kaplan-Meier survival curves for patients undergoing the Kasai operation at age ≤30, 31 to 90, and >90 days showed 49%, 36%, and 23%, respectively, were alive with their native liver at 4 years ( P < .0001). This difference continued through 10 years. The 2- and 4-year post-Kasai operation native liver survival rates were 47% and 35% for ERA I and 46% and 39% for ERA II ( P = NS). A total of 210 patients (60%) underwent liver transplantation; the 4-year transplantation survival rate was 82% (ERA I = 83%, ERA II = 82%; P = NS). Conclusions This is the largest outcome series of North American children with biliary atresia at a time when liver transplantation was available. Results in each era were similar. Late referral remains problematic; policies to ensure timely diagnosis are required. Nevertheless, outcomes in Canada are comparable to those reported elsewhere.
We have discovered a 300 kpc-wide giant Lyman-
α
(Ly
α
) nebula centered on the massive galaxy group RO-1001 at
z
= 2.91 in the Cosmic Evolution Survey field. Keck Cosmic Web Imager observations ...reveal three cold gas filaments converging into the center of the potential well of its ∼4 × 10
13
M
⊙
dark matter halo, hosting 1200
M
⊙
yr
−1
of star formation as probed by Atacama Large Millimeter Array and NOrthern Extended Millimeter Array observations. The nebula morphological and kinematics properties and the prevalence of blueshifted components in the Ly
α
spectra are consistent with a scenario of gas accretion. The upper limits on active galactic nuclei activity and overall energetics favor gravity as the primary Ly
α
powering source and infall as the main source of gas flows to the system. Although interpretational difficulties remain, with outflows and likely also photoionization with ensuing recombination still playing a role, this finding provides arguably an ideal environment to quantitatively test models of cold gas accretion and galaxy feeding inside an actively star-forming massive halo at high redshift.
Direct recognition of invading pathogens by innate immune cells is a critical driver of the inflammatory response. However, cells of the innate immune system can also sense their local ...microenvironment and respond to physiological fluctuations in temperature, pH, oxygen and nutrient availability, which are altered during inflammation. Although cells of the immune system experience force and pressure throughout their life cycle, little is known about how these mechanical processes regulate the immune response. Here we show that cyclical hydrostatic pressure, similar to that experienced by immune cells in the lung, initiates an inflammatory response via the mechanically activated ion channel PIEZO1. Mice lacking PIEZO1 in innate immune cells showed ablated pulmonary inflammation in the context of bacterial infection or fibrotic autoinflammation. Our results reveal an environmental sensory axis that stimulates innate immune cells to mount an inflammatory response, and demonstrate a physiological role for PIEZO1 and mechanosensation in immunity.
The flare of radiation from the tidal disruption and accretion of a star can be used as a marker for supermassive black holes that otherwise lie dormant and undetected in the centres of distant ...galaxies. Previous candidate flares have had declining light curves in good agreement with expectations, but with poor constraints on the time of disruption and the type of star disrupted, because the rising emission was not observed. Recently, two 'relativistic' candidate tidal disruption events were discovered, each of whose extreme X-ray luminosity and synchrotron radio emission were interpreted as the onset of emission from a relativistic jet. Here we report a luminous ultraviolet-optical flare from the nuclear region of an inactive galaxy at a redshift of 0.1696. The observed continuum is cooler than expected for a simple accreting debris disk, but the well-sampled rise and decay of the light curve follow the predicted mass accretion rate and can be modelled to determine the time of disruption to an accuracy of two days. The black hole has a mass of about two million solar masses, modulo a factor dependent on the mass and radius of the star disrupted. On the basis of the spectroscopic signature of ionized helium from the unbound debris, we determine that the disrupted star was a helium-rich stellar core.
Celotno besedilo
Dostopno za:
DOBA, IJS, IZUM, KILJ, KISLJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
A clumped particle model for rock Cho, N.; Martin, C.D.; Sego, D.C.
International journal of rock mechanics and mining sciences (Oxford, England : 1997),
10/2007, Letnik:
44, Številka:
7
Journal Article
Recenzirano
Discrete element (particle) modeling is now often used to simulate the behavior of rock. While the method is attractive because it does not require the formulation of complex constitutive models, it ...requires extensive calibration with measured macro-scale results to determine the particle–contact parameters that will predict the macro-scale response. This calibration is usually carried out using the laboratory uniaxial compression test. The behavior of intact rock in compression is complex, resulting in a nonlinear failure envelope with high frictional resistance and a ratio of tensile to uniaxial compression strength of approximately 0.05–0.1. An extensive series of calibrations were carried out using a particle code to determine if the micro-parameters determined from uniaxial compression tests could be used to predict the intact rock response regardless of stress path, i.e., tension to triaxial compression. It is determined that the particle code cannot predict the failure envelope measured on laboratory samples, unless significant modifications are made. This study shows that adjusting the particle parameters had little effect on the macro-scale properties of compression and tension tests, but using a clumped-particle geometry improves the predictive capabilities of the particle code significantly. For both Lac du Bonnet granite and a weak synthetic rock, the particle code calibrated to uniaxial tests using the clumped-particle geometry predicts both the stress–strain behavior and the complete nonlinear failure envelope.
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