13 research outputs found
BCS Instability and Finite Temperature Corrections to Tachyon Mass in Intersecting D1-Branes
A holographic description of BCS superconductivity is given in
arxiv:1104.2843. This model was constructed by insertion of a pair of D8-branes
on a D4-background. The spectrum of intersecting D8-branes has tachyonic modes
indicating an instability which is identified with the BCS instability in
superconductors. Our aim is to study the stability of the intersecting branes
under finite temperature effects. Many of the technical aspects of this problem
are captured by a simpler problem of two intersecting D1-branes on flat
background. In the simplified set-up we compute the one-loop finite temperature
corrections to the tree-level tachyon mass using the frame-work of SU(2)
Yang-Mills theory in (1 + 1)-dimensions. We show that the one-loop two-point
functions are ultraviolet finite due to cancellation of ultraviolet divergence
between the amplitudes containing bosons and fermions in the loop. The
amplitudes are found to be infrared divergent due to the presence of massless
fields in the loops. We compute the finite temperature mass correction to all
the massless fields and use these temperature dependent masses to compute the
tachyonic mass correction. We show numerically the existence of a transition
temperature at which the effective mass of the tree-level tachyons becomes
zero, thereby stabilizing the brane configuration.Comment: Article, 95 pages, 59 figures, improved numerics, added reference
Finite Temperature Corrections to Tachyon Mass in Intersecting D-Branes
We continue with the analysis of finite temperature corrections to the
Tachyon mass in intersecting branes which was initiated in arxiv:1403.0389. In
this paper we extend the computation to the case of intersecting D3-branes by
considering a setup of two intersecting branes in flat-space background. A
holographic model dual to BCS superconductor consisting of intersecting
D8-branes in D4-brane background was proposed in arxiv:1104.2843. The
background considered here is a simplified configuration of this dual model. We
compute the one-loop Tachyon amplitude in the Yang-Mills approximation and show
that the result is finite. Analyzing the amplitudes further we numerically
compute the transition temperature at which the Tachyon becomes massless. The
analytic expressions for the one-loop amplitudes obtained here reduce to those
for intersecting D1-branes obtained in arxiv:1403.0389 as well as those for
intersecting D2-branes.Comment: 73 pages, 24 figures, articl
Some BPS configurations of the BLG Theory
We obtain BPS configurations of the BLG theory and its variant including mass
terms for scalars and fermions in addition to a background field with different
world-volume and R-symmetries. Three cases are considered, with world-volume
symmetries SO(1,1) and SO(2) and preserving different amounts of supersymmetry.
In the former case we obtain a singular configuration preserving N=(3,3)
supersymmetry and an one-quarter BPS configuration corresponding to
intersecting M2-M5-M5-branes. In the latter instance the BPS equations are
reduced to those in the self-dual Chern-Simons theory with two complex scalars.
In want of an exact solution, we find a topological vortex solution numerically
in this case. Other solutions are given by combinations of domain walls.Comment: 15 pages, 3 figure
Superstring partition functions in the doubled formalism
Computation of superstring partition function for the non-linear sigma model
on the product of a two-torus and its dual within the scope of the doubled
formalism is presented. We verify that it reproduces the partition functions of
the toroidally compactified type--IIA and type--IIB theories for appropriate
choices of the GSO projection.Comment: 15 page
Oral Abstracts 7: RA ClinicalO37. Long-Term Outcomes of Early RA Patients Initiated with Adalimumab Plus Methotrexate Compared with Methotrexate Alone Following a Targeted Treatment Approach
Background: This analysis assessed, on a group level, whether there is a long-term advantage for early RA patients treated with adalimumab (ADA) + MTX vs those initially treated with placebo (PBO) + MTX who either responded to therapy or added ADA following inadequate response (IR). Methods: OPTIMA was a 78- week, randomized, controlled trial of ADA + MTX vs PBO + MTX in MTX-naïve early (<1 year) RA patients. Therapy was adjusted at week 26: ADA + MTX-responders (R) who achieved DAS28 (CRP) <3.2 at weeks 22 and 26 (Period 1, P1) were re-randomized to withdraw or continue ADA and PBO + MTX-R continued randomized therapy for 52 weeks (P2); IR-patients received open-label (OL) ADA + MTX during P2. This post hoc analysis evaluated the proportion of patients at week 78 with DAS28 (CRP) <3.2, HAQ-DI <0.5, and/or ΔmTSS ≤0.5 by initial treatment. To account for patients who withdrew ADA during P2, an equivalent proportion of R was imputed from ADA + MTX-R patients. Results: At week 26, significantly more patients had low disease activity, normal function, and/or no radiographic progression with ADA + MTX vs PBO + MTX (Table 1). Differences in clinical and functional outcomes disappeared following additional treatment, when PBO + MTX-IR (n = 348/460) switched to OL ADA + MTX. Addition of OL ADA slowed radiographic progression, but more patients who received ADA + MTX from baseline had no radiographic progression at week 78 than patients who received initial PBO + MTX. Conclusions: Early RA patients treated with PBO + MTX achieved comparable long-term clinical and functional outcomes on a group level as those who began ADA + MTX, but only when therapy was optimized by the addition of ADA in PBO + MTX-IR. Still, ADA + MTX therapy conferred a radiographic benefit although the difference did not appear to translate to an additional functional benefit. Disclosures: P.E., AbbVie, Merck, Pfizer, UCB, Roche, BMS—Provided Expert Advice, Undertaken Trials, AbbVie—AbbVie sponsored the study, contributed to its design, and participated in the collection, analysis, and interpretation of the data, and in the writing, reviewing, and approval of the final version. R.F., AbbVie, Pfizer, Merck, Roche, UCB, Celgene, Amgen, AstraZeneca, BMS, Janssen, Lilly, Novartis—Research Grants, Consultation Fees. S.F., AbbVie—Employee, Stocks. A.K., AbbVie, Amgen, AstraZeneca, BMS, Celgene, Centocor-Janssen, Pfizer, Roche, UCB—Research Grants, Consultation Fees. H.K., AbbVie—Employee, Stocks. S.R., AbbVie—Employee, Stocks. J.S., AbbVie, Amgen, AstraZeneca, BMS, Celgene, Centocor-Janssen, GlaxoSmithKline, Lilly, Pfizer (Wyeth), MSD (Schering-Plough), Novo-Nordisk, Roche, Sandoz, UCB—Research Grants, Consultation Fees. R.V., AbbVie, BMS, GlaxoSmithKline, Human Genome Sciences, Merck, Pfizer, Roche, UCB Pharma—Consultation Fees, Research Support. Table 1.Week 78 clinical, functional, and radiographic outcomes in patients who received continued ADA + MTX vs those who continued PBO + MTX or added open-label ADA following an inadequate response ADA + MTX, n/N (%)a PBO + MTX, n/N (%)b Outcome Week 26 Week 52 Week 78 Week 26 Week 52 Week 78 DAS28 (CRP) <3.2 246/466 (53) 304/465 (65) 303/465 (65) 139/460 (30)*** 284/460 (62) 300/460 (65) HAQ-DI <0.5 211/466 (45) 220/466 (47) 224/466 (48) 150/460 (33)*** 203/460 (44) 208/460 (45) ΔmTSS ≤0.5 402/462 (87) 379/445 (86) 382/443 (86) 330/459 (72)*** 318/440 (72)*** 318/440 (72)*** DAS28 (CRP) <3.2 + ΔmTSS ≤0.5 216/462 (47) 260/443 (59) 266/443 (60) 112/459 (24)*** 196/440 (45) 211/440 (48)*** DAS28 (CRP) <3.2 + HAQ-DI <0.5 + ΔmTSS ≤0.5 146/462 (32) 168/443 (38) 174/443 (39) 82/459 (18)*** 120/440 (27)*** 135/440 (31)** aIncludes patients from the ADA Continuation (n = 105) and OL ADA Carry On (n = 259) arms, as well as the proportional equivalent number of responders from the ADA Withdrawal arm (n = 102). bIncludes patients from the MTX Continuation (n = 112) and Rescue ADA (n = 348) arms. Last observation carried forward: DAS28 (CRP) and HAQ-DI; Multiple imputations: ΔmTSS. ***P < 0.001 and **iP < 0.01, respectively, for differences between initial treatments from chi-squar