1,910 research outputs found
Deconstructing graviphoton from mass-deformed ABJM
Mass-deformed ABJM theory has a maximally supersymmetric fuzzy two-sphere
vacuum solution where the scalar fields are proportional to the TGRVV matrices.
We construct these matrices using Schwinger oscillators. This shows that the
ABJM gauge group that corresponds to the fuzzy two-sphere geometry is
. We deconstruct the graviphoton term in the D4 brane
theory. The normalization of this term is fixed by topological reasons. This
gives us the correct normalization of the deconstructed U(1) gauge field and
fixes the Yang -Mills coupling constant to the value which corresponds to M5
brane compactified on \mb{R}^ {1,2} \times S^3/{\mb{Z}_k}. The graviphoton
term also enable us to show that the zero mode contributions to the partition
functions for the D4 and the M5 brane agree.Comment: 26 page
Comparison of methods for determining the fatty acid composition of photosynthetic tissues
The fatty acid (FA) composition of photosynthetic tissue differs from that in other plant or animal tissues. In leaves, the lipid fraction constitutes less than 10% of the dry weight and is mostly located in the chloroplasts. An extraction solvent should dissolve polar lipids readily, but should also overcome interactions between the lipids and the tissue matrix. A mixture of chloroform/methanol (C/M) is commonly used. However, less toxic alternative methods such as hexane/isopropanol (H/I) and ethanol (E) have been suggested. In this preliminary study we compared the effectiveness of these three methods which are used as standard extraction protocols for FA analysis of plant material at three different European Universities. C/M extraction gave the highest total FA content and H/I the lowest, suggesting that C/M is indeed the best general-purpose lipid extraction solvent. Significant differences were also observed for FA composition including the ratio of saturated to unsaturated FA indicating selectivity of the various solvents in extracting different individual FA. Further and more detailed investigations are required to confirm this hypothesi
The effect of N-fertilisation rate or inclusion of red clover to timothy leys on fatty acid composition in milk of dairy cows fed a commercial silage:concentrate ratio
The aim of this experiment was to, under typical Swedish production conditions, evaluate the effects of grass silages subjected to different N-fertilisation regimes fed to dairy cows on the fatty acid (FA) composition of their milk, and to compare the grass silages in this respect to red clover-dominated silage. Grass silages made from first year Phleum pratense L. leys subjected to three N-fertilisation regimes (30, 90 and 120 kg N/ha, designated G-30, G-90 and G-120, respectively) and a mixed red clover grass silage (Trifolium pratense L. and P. pratense L; 60/40 on dry matter (DM) basis, designated RC G) were produced. The experiment was conducted as a change-over design, including 24 primiparous and multiparous dairy cows of the Swedish Red breed, each of which was allocated to three of the four diets. The cows were offered 11 kg DM of silage and 7 kg concentrates. The silages had similar DM and energy concentrations. The CP concentration increased with increase in N-fertilisation level. There was a linear increase in DM intake of the different silages with increased N fertilisation. There were also differences in concentrations of both individual and total FAs amongst silages. The daily milk production (kg/day) did not significantly differ between treatments, but G-30 silage resulted in higher concentrations of 18:2n-6 in the milk compared with the other two grass silages. The highest concentrations of 18:3n-3 and cis-9, trans-11 18:2 were found in milk from cows offered the RC G silage. The G-30 diet resulted in higher concentration of 18:2n-6 and the same concentration of 18:3n-3 in the milk as the other grass silages, despite lower intake levels of these FAs. The apparent recoveries of 18:3n-3 from feed to milk were 5.74%, 4.27%, 4.10% and 5.31% for G-30, G-90, G-120 and RC G, respectively. A higher recovery when red clover is included in the diet confirms previous reports. The higher apparent recovery of 18:3n-3 on the G-30 treatment may be related to the lower silage DM intake, which led to a higher relative proportion of ingested FAs originating from concentrates compared with the G-90 and G-120 diets. With the rates and types of concentrates used in this study, the achieved differences in FA composition among the silages were not enough to influence the concentrations of unsaturated FAs in milk
Frequency-selective single photon detection using a double quantum dot
We use a double quantum dot as a frequency-tunable on-chip microwave detector
to investigate the radiation from electron shot-noise in a near-by quantum
point contact. The device is realized by monitoring the inelastic tunneling of
electrons between the quantum dots due to photon absorption. The frequency of
the absorbed radiation is set by the energy separation between the dots, which
is easily tuned with gate voltages. Using time-resolved charge detection
techniques, we can directly relate the detection of a tunneling electron to the
absorption of a single photon
Classification of N=6 superconformal theories of ABJM type
Studying the supersymmetry enhancement mechanism of Aharony, Bergman,
Jafferis and Maldacena, we find a simple condition on the gauge group
generators for the matter fields. We analyze all possible compact Lie groups
and their representations. The only allowed gauge groups leading to the
manifest N=6 supersymmetry are, up to discrete quotients, SU(n) x U(1), Sp(n) x
U(1), SU(n) x SU(n), and SU(n) x SU(m) x U(1) with possibly additional U(1)'s.
Matter representations are restricted to be the (bi)fundamentals. As a
byproduct we obtain another proof of the complete classification of the three
algebras considered by Bagger and Lambert.Comment: 18 page
Duality between N=5 and N=6 Chern-Simons matter theory
We provide evidences for the duality between Chern-Simons matter theory and theory for a suitable by working out the
superconformal index, which shows perfect matching. For theories,
we show that supersymmetry is enhanced to by explicitly
constructing monopole operators filling in -currents. Finally we
work out the large index of and show that
it exactly matches with the gravity index on , which
further provides additional evidence for the duality between the
and theory for Comment: 15 pages; references adde
Review of carcinogenicity of asbestos and proposal of approval standards of an occupational cancer caused by asbestos in Korea
Ion counting efficiencies at the IGISOL facility
At the IGISOL-JYFLTRAP facility, fission mass yields can be studied at high
precision. Fission fragments from a U target are passing through a Ni foil and
entering a gas filled chamber. The collected fragments are guided through a
mass separator to a Penning trap where their masses are identified. This
simulation work focuses on how different fission fragment properties (mass,
charge and energy) affect the stopping efficiency in the gas cell. In addition,
different experimental parameters are varied (e. g. U and Ni thickness and He
gas pressure) to study their impact on the stopping efficiency. The simulations
were performed using the Geant4 package and the SRIM code. The main results
suggest a small variation in the stopping efficiency as a function of mass,
charge and kinetic energy. It is predicted that heavy fragments are stopped
about 9% less efficiently than the light fragments. However it was found that
the properties of the U, Ni and the He gas influences this behavior. Hence it
could be possible to optimize the efficiency.Comment: 52 pages, 44 figure
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