530 research outputs found
Semiclassical Strings in Electric and Magnetic Fields Deformed Spacetimes
We first apply the transformation of mixing azimuthal and internal coordinate
or mixing time and internal coordinate to the 11D M-theory with a stack N
M2-branes to find the spacetime of a stack of N D2-branes with magnetic or
electric flux in 10 D IIA string theory, after the Kaluza-Klein reduction. We
then perform the T duality to the spacetime to find the background of a stack
of N D3-branes with magnetic or electric flux. In the near-horizon limit the
background becomes the magnetic or electric field deformed .
We adopt an ansatz to find the classical string solution which is rotating in
the deformed with three angular momenta in the three rotation planes. The
relations between the classical string energy and its angular momenta are found
and results show that the external magnetic and electric fluxes will increase
the string energy. Therefore, from the AdS/CFT point of view, the corrections
of the anomalous dimensions of operators in the dual SYM theory will be
positive. We also investigate the small fluctuations in these solutions and
discuss the effects of magnetic and electric fields on the stability of these
classical rotating string solutions. Finally, we find the possible solutions of
string pulsating on the deformed spacetimes and show that the corrections to
the anomalous dimensions of operators in the dual SYM theory are non-negative.Comment: Latex 18 pages, correct sec. 3.
Boundary Superstring Field Theory Annulus Partition Function in the Presence of Tachyons
We compute the Boundary Superstring Field Theory partition function on the
annulus in the presence of independent linear tachyon profiles on the two
boundaries. The R-R sector is found to contribute non-trivially to the
derivative terms of the space-time effective action. In the process we
construct a boundary state description of D-branes in the presence of a linear
tachyon. We quantize the open string in a tachyonic background and address the
question of open/closed string duality.Comment: 31 pages, 1 figure, LaTeX; v2 32 pages, references added, typos
corrected, discussion of open string normal ordering constant modifie
Early increase in blood pressure and diastolic left ventricular malfunction in patients with glomerulonephritis
Early increase in blood pressure and diastolic left ventricular malfunction in patients with glomerulonephritis. In patients with diabetic nephropathy blood pressure increases progressively before the conventional threshold of normal blood pressure (140/90mm Hg) is transgressed. In patients with glomerulonephritis, no information on this point is available. To clarify this issue we sequentially examined 20 untreated patients with biopsy-proven primary chronic glomerulonephritis (GN) who had casual blood pressure below 140/90mm Hg and normal GFR by inulin clearance. Patients were compared with normotensive healthy controls who were matched for BMI, gender and age. We measured ambulatory 24-hour blood pressure (SpaceLab system), echocardiography (ASE criteria, Acuson 128 XP 10), CIn and CPAH, urinary Na excretion, PRA and insulin concentration. In patients with GN, the median 24 hour (P < 0.0005), daytime (P < 0.001) and nocturnal sleeping time (P < 0.0001) MAP values were significantly higher than in matched controls (daytime, mean 97mm Hg, 85 to 106 GN vs. 89 controls range 82 to 102; nocturnal sleeping time, mean 80.3mm Hg, 71 to 89.5 GN vs. 73 controls, range 63 to 84). Echocardiographic examination showed significantly greater posterior wall thickness (P < 0.01) and ventricular septal thickness (P < 0.003). In addition the early diastolic to late diastolic (E/A) ratio of mitral valve peak inflow velocity was significantly (P < 0.0008) lower in patients. The data point to left ventricular wall thickening accompanied by LV diastolic malfunction. The study documents elevated ambulatory blood pressure in patients with primary chronic glomerulonephritis despite normal body weight and normal GFR. This is associated with evidence of target organ damage in the heart. The findings suggest that in patients with glomerulonephritis blood pressure increases initially within the normotensive range. This observation in conjunction with evidence of early target organ changes provides an argument for early antihypertensive intervention, but controlled trials to test efficacy and safety of this proposal are necessary
Hallucinogenic potential: a review of psychoplastogens for the treatment of opioid use disorder
The United States is entering its fourth decade of the opioid epidemic with no clear end in sight. At the center of the epidemic is an increase in opioid use disorder (OUD), a complex condition encompassing physical addiction, psychological comorbidities, and socioeconomic and legal travails associated with the misuse and abuse of opioids. Existing behavioral and medication-assisted therapies show limited efficacy as they are hampered by lack of access, strict regimens, and failure to fully address the non-pharmacological aspects of the disease. A growing body of research has indicated the potential of hallucinogens to efficaciously and expeditiously treat addictions, including OUD, by a novel combination of pharmacology, neuroplasticity, and psychological mechanisms. Nonetheless, research into these compounds has been hindered due to legal, social, and safety concerns. This review will examine the preclinical and clinical evidence that psychoplastogens, such as ibogaine, ketamine, and classic psychedelics, may offer a unique, holistic alternative for the treatment of OUD while acknowledging that further research is needed to establish long-term efficacy along with proper safety and ethical guidelines
On Integrability of Classical SuperStrings in AdS_5 x S^5
We explore integrability properties of superstring equations of motion in
AdS_5 x S^5. We impose light-cone kappa-symmetry and reparametrization gauges
and construct a Lax representation for the corresponding Hamiltonian dynamics
on subspace of physical superstring degrees of freedom. We present some
explicit results for the corresponding conserved charges by consistently
reducing the dynamics to AdS_3 x S^3 and AdS_3 x S^1 subsectors containing both
bosonic and fermionic fields.Comment: JHEP style, 32 pages; v2: refined discussion of monodromy, refs adde
On the fermionic T-duality of the AdS_4 \times CP^3 sigma-model
In this note we consider a fermionic T-duality of the coset realization of
the type IIA sigma-model on AdS_4 \times CP^3 with respect to the three flat
directions in AdS_4, six of the fermionic coordinates and three of the CP^3
directions. We show that the Buscher procedure fails as it leads to a singular
transformation and discuss the result and its implications.Comment: LaTeX2e, 9 pages, no figures, JHEP style; v2: minor clarifications;
v3: typos fixed, matches the published versio
Semiclassical Strings on AdS_5 x S^5/Z_M and Operators in Orbifold Field Theories
We show agreements, at one-loop level of field theory, between energies of
semiclassical string states on AdS_5 x S^5/Z_M and anomalous dimensions of
operators in N=0,1,2 orbifold field theories originating from N=4 SYM. On field
theory side, one-loop anomalous dimension matrices can be regarded as
Hamiltonians of spin chains with twisted boundary conditions. These are
solvable by Bethe ansatz. On string side, twisted sectors emerge and we obtain
some string configurations in twisted sectors. In SU(2) subsectors, we compare
anomalous dimensions with string energies and see agreements. We also see
agreements between sigma models of both sides in SU(2) and SU(3) subsectors.Comment: LaTeX, 23 pages, 4 figures; v2 minor corrections, added references;
v3 typos corrected, published versio
Formation of Centauro and Strangelets in Nucleus-Nucleus Collisions at the LHC and their Identification by the ALICE Experiment
We present a phenomenological model which describes the formation of a
Centauro fireball in nucleus-nucleus interactions in the upper atmosphere and
at the LHC, and its decay to non-strange baryons and Strangelets. We describe
the CASTOR detector for the ALICE experiment at the LHC. CASTOR will probe, in
an event-by-event mode, the very forward, baryon-rich phase space 5.6 < \eta <
7.2 in 5.5 A TeV central Pb + Pb collisions. We present results of simulations
for the response of the CASTOR calorimeter, and in particular to the traversal
of Strangelets.Comment: 4 pages, 4 figures, to appear in the proceedings of the 26th ICR
Circular and Folded Multi-Spin Strings in Spin Chain Sigma Models
From the SU(2) spin chain sigma model at the one-loop and two-loop orders we
recover the classical circular string solution with two S^5 spins (J_1, J_2) in
the AdS_5 x S^5 string theory. In the SL(2) sector of the one-loop spin chain
sigma model we explicitly construct a solution which corresponds to the folded
string solution with one AdS_5 spin S and one S^5 spin J. In the one-loop
general sigma model we demonstrate that there exists a solution which
reproduces the energy of the circular constant-radii string solution with three
spins (S_1, S_2, J).Comment: 16 pages, LaTeX, no figure
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