27,227 research outputs found
A bibliography of six years (1951-1956) research in arithmetic
Thesis (Ed.M.)--Boston Universit
Incorporation of amino acids into the outer and inner membrane of isolated rat liver mitochondria II
EPR of Cu\u3csup\u3e2+\u3c/sup\u3e Prion Protein Constructs at 2 GHz Using the \u3cem\u3eg\u3c/em\u3e\u3csub\u3e⊥\u3c/sub\u3e Region to Characterize Nitrogen Ligation
A double octarepeat prion protein construct, which has two histidines, mixed with copper sulfate in a 3:2 molar ratio provides at most three imidazole ligands to each copper ion to form a square-planar Cu2+ complex. This work is concerned with identification of the fourth ligand. A new (to our knowledge) electron paramagnetic resonance method based on analysis of the intense features of the electron paramagnetic resonance spectrum in the g⊥ region at 2 GHz is introduced to distinguish between three and four nitrogen ligands. The methodology was established by studies of a model system consisting of histidine imidazole ligation to Cu2+. In this spectral region at 2 GHz (S-band), g-strain and broadening from the possible rhombic character of the Zeeman interaction are small. The most intense line is identified with the MI = +1/2 extra absorption peak. Spectral simulation demonstrated that this peak is insensitive to cupric Ax and Ay hyperfine interaction. The spectral region to the high-field side of this peak is uncluttered and suitable for analysis of nitrogen superhyperfine couplings to determine the number of nitrogens. The spectral region to the low-field side of the intense extra absorption peak in the g⊥ part of the spectrum is sensitive to the rhombic distortion parameters Ax and Ay. Application of the method to the prion protein system indicates that two species are present and that the dominant species contains four nitrogen ligands. A new loop-gap microwave resonator is described that contains ∼1 mL of frozen sample
Resonance lamp absorption measurement of OH number density and temperature in expansion tube scramjet engine tests
In this paper, we report results of hydroxyl radical and static temperature measurements performed in the General Applied Science Laboratories-NASA HYPULSE expansion tube facility using the microwave resonance lamp absorption technique. Data were obtained as part of a series of hydrogen/air and hydrogen/oxygen combustion tests at stagnation enthalpies corresponding to Mach 17 flight speeds. Data from a representative injector configuration is compared to a full Navier-Stokes CFD solution
Flavour-Condensate-induced Breaking of Supersymmetry in Free Wess-Zumino Fluids
Recently we argued that a particular model of string-inspired quantum
space-time foam (D-foam) may induce oscillations and mixing among flavoured
particles. As a result, rather than the mass-eigenstate vacuum, the correct
ground state to describe the underlying dynamics is the flavour vacuum,
proposed some time ago by Blasone and Vitiello as a description of quantum
field theories with mixing. At the microscopic level, the breaking of
target-space supersymmetry is induced in our space-time foam model by the
relative transverse motion of brane defects. Motivated by these results, we
show that the flavour vacuum, introduced through an inequivalent representation
of the canonical (anti-) commutation relations, provides a vehicle for the
breaking of supersymmetry (SUSY) at a low-energy effective field theory level;
on considering the flavour-vacuum expectation value of the energy-momentum
tensor and comparing with the form of a perfect relativistic fluid, it is found
that the bosonic sector contributes as dark energy while the fermion
contribution is like dust. This indicates a strong and novel breaking of SUSY,
of a non-perturbative nature, which may characterize the low energy field
theory of certain quantum gravity models.Comment: Discussion added in sections II and IV on quantum-gravity induced
flavour mixing, references added, conclusions unchange
Expanded Very Large Arrays Observations of a Proto-Cluster of Molecular Gas-Rich Galaxies at z = 4.05
We present observations of the molecular gas in the GN20 proto-cluster of galaxies at z = 4.05 using the Expanded Very Large Array (EVLA). This group of galaxies is the ideal laboratory for studying the formation of massive galaxies via luminous, gas-rich starbursts within 1.6 Gyr of the big bang. We detect three galaxies in the proto-cluster in CO 2-1 emission, with gas masses (H_2) between 10^(10) and 10^(11) × (α/0.8) M_⊙. The emission from the brightest source, GN20, is resolved with a size ~2'' and has a clear north-south velocity gradient, possibly indicating ordered rotation. The gas mass in GN20 is comparable to the stellar mass (1.3 × 10^(11) × (α/0.8) M_⊙ and 2.3 × 10^(11) M_⊙, respectively), and the sum of gas plus stellar mass is comparable to the dynamical mass of the system (~3.4 × 10^(11)[sin (i)/sin (45°)]^(–2) M_⊙), within a 5 kpc radius. There is also evidence for a tidal tail extending another 2'' north of the galaxy with a narrow velocity dispersion. GN20 may be a massive, gas-rich disk that is gravitationally disturbed, but not completely disrupted. There is one Lyman-break galaxy (BD29079) in the GN20 proto-cluster with an optical spectroscopic redshift within our search volume, and we set a 3σ limit to the molecular gas mass of this galaxy of 1.1 × 10^(10) × (α/0.8) M_⊙
Rex E. Lee Conference on the Office of the Solicitor General of the United States: Clinton II Panel
I will say a few words about Dickerson, both because Michael has made it impossible not to and also because in some ways it represents the very best about how all of the wonderful, tried-and-true processes of the SG\u27s Office ought to work. Dickerson was very much like the other case that Michael talked about (which is one of, I think, two significant privilege controversies which the Independent Counsel laid on our doorstep). These cases may have appeared to the outside world as paradigmatically cases in which we would be hearing from the White House, or talking to the White House, or thinking about things other than the long-term institutional interests of the United States. But absolutely nothing of the sort ever happened, nor was any effort made by any political person to intrude in our decision-making policy
Anisotropic pair-superfluidity of trapped two-component Bose gases
We theoretically investigate the pair-superfluid phase of two-component
ultracold gases with negative inter-species interactions in an optical lattice.
We establish the phase diagram for filling at zero and finite
temperature, by applying Bosonic Dynamical Mean-Field Theory, and confirm the
stability of pair-superfluidity for asymmetric hopping of the two species.
While the pair superfluid is found to be robust in the presence of a harmonic
trap, we observe that it is destroyed already by a small population imbalance
of the two species.Comment: 7 pages, 11 figure
Injury From White Grubs in Iowa
The serious outbreaks of white grubs that have occurred in northeastern Iowa during the past ten years are part of a general outbreak appearing in a number of more or less timbered areas in a belt running from Minnesota and Iowa east to New York, Connecticut and New Jersey. These grubs first appeared in unusual number in 1909, increased in severity in 1912 and reached a climax of injury in 1915. In 1918 the damage was considerably less than in the previous outbreak and it is probable that the parasites and other enemies of the grubs will reduce their numbers to a nearly normal amount by 1921 or 1924 at the latest
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