2,662 research outputs found
M5-brane Effective Action as an On-shell Action in Supergravity
We show that the covariant effective action for M5-brane is a solution to the
Hamilton-Jacobi (H-J) equations of 11-dimensional supergravity. The solution to
the H-J equations reproduces the supergravity solution that represents the
M2-M5 bound states.Comment: 20 pages, references added, typos correcte
Practical Application of Near-Infrared Spectroscopy for Determining Rice Amylose Content at Grain Elevator
The major chemical constituent contents of rice are moisture, protein and starch (amylose and amylopectin). Those constituent contents associate with eating quality of rice. Near-infrared (NIR) spectroscopy is one of the non-destructive methods for determining grain chemical contents. At grain elevator, moisture and protein contents can be measured with high accuracy using an NIR spectrometer by the effort of our research activities in Japan. However, the accuracy to determine amylose content is not sufficient. Thus, the objective of this study was to develop non-destructive method to determine rice amylose content for practical use at grain elevator. Milled rice amylose content measurement was performed using an auto-analyzer for reference (chemical) analysis. Spectra data of milled rice were obtained using an NIR spectrometer with a wavelength range of 850 to 1048 nm. Calibration model to determine amylose content was developed using non-waxy Japonica-type rice samples. Partial least squares (PLS) regression analysis was used to develop calibration model. The accuracy of the model was validated and the validation statistics were shown: coefficient of determination (r2) was 0.72, bias was -0.04%, standard error of prediction (SEP) was 0.92%, and ratio of SEP to standard deviation of reference data (RPD) was 1.90. Production year of the validation set (2017) was different from that of the calibration set (2008 to 2016). This means the same condition as practical use of this method at grain elevator. The result obtained in this study indicated that this calibration model enables non-destructive determination of rice amylose content at grain elevator.  
Angioscopic Evaluation of Thrombi in the Culprit Coronary Lesions in Patients With Acute Myocardial Infarction
The purpose of this study was to evaluate intracoronary thrombi in
the culprit lesions in patients with acute myocardial infarction
(AMI) by angioscopy, and to compare them with clinical and
angiographic features. We angioscopically observed the culprit
coronary lesions in 66 patients with AMI (55 males and 11
females, 63.9±15.4 years old) just before interventional
therapy. Thrombi were observed in 42 of 66 lesions
(64%), namely, red thrombi in 16, mixed thrombi in 15,
white thrombi in 11. In patients with complete obstruction
(TIMI grade 0 and I), red thrombi were more frequently
observed than mixed or white thrombi. On the other hand, in
patients with incomplete obstruction (TIMI grade II and
III), white thrombi were more frequently observed than the
others. Angiographically, haziness and filling defect were
significantly more frequently observed in patients with red
thrombi than the others (p<0.05). The distance from
proximal side branch to thrombi tended to be longer in patients
with red thrombi than the others. The time from onset of AMI
tended to be longer in patients with white thrombi than the
others. These results suggest that blood flow may be an important
determinant of thrombi characterization
Multiple nearest-neighbor exchange model for the frustrated magnetic molecules Mo72Fe30 and Mo72Cr30
Our measurements of the differential susceptibility dM/dH of the frustrated
magnetic molecules Mo72Fe30 and Mo72Cr30 reveal a pronounced dependence on
magnetic field (H) and temperature (T) in the low H - low T regime, contrary to
the predictions of existing models. Excellent agreement with experiment is
achieved upon formulating a nearest-neighbor classical Heisenberg model where
the 60 nearest-neighbor exchange interactions in each molecule, rather than
being identical as has been assumed heretofore, are described by a
two-parameter probability distribution of values of the exchange constant. We
suggest that the probability distribution provides a convenient
phenomenological platform for summarizing the combined effects of multiple
microscopic mechanisms that disrupt the idealized picture of a Heisenberg model
based on a single value of the nearest-neighbor exchange constant.Comment: 8 pages, 5 figure
Hagedorn Strings and Correspondence Principle in AdS(3)
Motivated by the possibility of formulating a strings/black hole
correspondence in AdS space, we extract the Hagedorn behavior of thermal AdS_3
bosonic string from 1-loop partition function of SL(2,R) WZW model. We find
that the Hagedorn temperature is monotonically increasing as the AdS radius
shrinks, reaches a maximum of order of string scale set by the unitarity bound
of the CFT for internal space. The resulting density of states near the
Hagedorn temperature resembles the form as for strings in flat space and is
dominated by the space-like long string configurations. We then argue a
conjectured strings/black hole correspondence in AdS space by applying the
Hagedorn thermodynamics. We find the size of the corresponding black hole is a
function of the AdS radius. For large AdS radius a black hole far bigger than
the string scale will form. On the contrary, when the AdS and string scales are
comparable a string size black hole will form. We also examine strings on BTZ
background obtained through SL(2,Z) transformation. We find a tachyonic
divergence for a BTZ black hole of string scale size.Comment: 28 pages, 4 figures;v2 references added & appear on JHE
Page charge of D-branes and its behavior in topologically nontrivial B-fields
The RR Page charges for the D(2p+1)-branes with B-field in type IIB
supergravity are constructed consistently from brane source currents. The
resulting Page charges are B-independent in the nontrivial and intricate way.
It is found that in topologically trivial B-field the Page charge is conserved,
but in the topologically nontrivial B-field it is no longer to be conserved,
instead there is a jump between two Page charges defined in each patch, and we
interpret this jump as Hanany-Witten effect.Comment: 25 pages, 4 figures, typos corrected and reference adde
Zero-Mode Dynamics of String Webs
At sufficiently low energy the dynamics of a string web is dominated by zero
modes involving rigid motion of the internal strings. The dimension of the
associated moduli space equals the maximal number of internal faces in the web.
The generic web moduli space has boundaries and multiple branches, and for webs
with three or more faces the geometry is curved. Webs can also be studied in a
lift to M-theory, where a string web is replaced by a membrane wrapped on a
holomorphic curve in spacetime. In this case the moduli space is complexified
and admits a Kaehler metric.Comment: LaTeX, 17 pages, 5 eps figures; v2: references adde
Moduli Space Dimensions of Multi-Pronged Strings
The numbers of bosonic and fermionic zero modes of multi-pronged strings are
counted in super-Yang-Mills theory and compared with those of the
IIB string theory. We obtain a nice agreement for the fermionic zero modes,
while our result for the bosonic zero modes differs from that obtained in the
IIB string theory. The possible origin of the discrepancy is discussedComment: 15 pages, 2 figure
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